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  • 251.
    Lindfors, Caroline
    et al.
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Sports Medicine.
    Buer, Alma
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Sports Medicine.
    Blodstatus i förhållande till kön och kroppskomposition bland idrottsgymnasieelever2014Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Young athletes are still growing and it is important for them to have an adequate intake of energy that includes carbohydrates, proteins, fats, vitamins and minerals. Insufficient intake can lead to celldamage, weight loss, worse performance and a higher risk for colds or sports injuries. Young girls are at higher risks with an insufficient intake because of the female athlete triad. Iron is one of the most important mineral and helps with the oxygen transport when it is combined with Hb. Iron sufficiency is the most common nutrition insufficiency in the whole world. Approximately all oxygen within the red blood cells binds to Hb and enables oxygen transport within the blood. One gram of Hb binds to 1,34 ml O2. C-vitamin helps the absorption of iron, while as thee, coffee and wholemeal prevents it. Anemia is common in athletes and specifically women because of menstruation. Anemia leads to inferior oxygen transport and causes an impaired performance. The aim of this study was to examine the effects on blood count, fat mass, gender and type of sport of 16 year old students in high school with sports focus. The material that we have used is from an ongoing research that includes 91 young athletes and the significance level is 0,05 in this study. The results show that boys have higher Hb than girls and that girls have more fat mass than boys. It also show that six persons have anemia (less than 120 g/L Hb in women and less than 130 g/L Hb in men). Hb, ferritin, fat mass, EPK and EVF are significant between boys and girls. Surprisingly do not iron differ between the genders. The results also show that the adolescents have a good fat mass and that fat does not correlate with blood count. Measuring serum ferritin can give you valuable information about iron stores in the body and if you are iron insufficient. There are many discussions about low-fat diets and how that can be bad for the body and the performance. Low-fat diets are usually found in athletes where the weight is of importance. That is not the issue in this study. Other studies show a connection between low body fat and worse performance in elite endurance runners. Other studies have also found that anemia is more common in athletes than non-athletes.

  • 252.
    Lindfors, Marielle
    et al.
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Sports Medicine.
    Holmgren, Sara
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Sports Medicine.
    Utvärdering och jämförelse av olika fälttester för fotbollsspelare2012Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Different field tests are currently used in a wide extent in different levels of soccer teams. To be able to assess the players’ physiological status the tests must have high validity, reliability and external validity. Many different tests have been developt, but currently only five of these tests are most commonly used: Yo-Yo intermittent recovery test (YIRT), Yo-Yo intermittent endurance test (YIET), Multi-sprint-test, Beep-test and Cooper-test. Presently there is no definitive conclusion regarding which of these tests is most suitable for soccer players. Therefore the present study aimed to, on the basis of previous studies evaluate the advantages and disadvantages of the five most commonly used field test; to analyze the physiological requirements on soccer players with respect to their aerobic and anaerobic capacity; and last to compare among the five field tests and evaluate the validity of the field tests through comparison of field tests results with results from laboratory and soccer matches.

    During soccer match about 75-96 % of the energy is provided by the aerobic systems, while the rest, 4-25 %, is provided by the anaerobic systems. This fits approximately most of the results from both field tests and laboratory tests through measurement of either pulse, running distance, VO2max or lactate. Among the five tests, Yo-Yo tests (YIRT and YIET) has the best correlation to soccer match with respect to physiological demands on both aerobic and anaerobic capacities. Among the different Yo-Yo tests YIRT2 seems to be the best compared to YIET1, YIET2 and YIRT1. 

  • 253. Lindgren, Cecilia M
    et al.
    Heid, Iris M
    Randall, Joshua C
    Lamina, Claudia
    Steinthorsdottir, Valgerdur
    Qi, Lu
    Speliotes, Elizabeth K
    Thorleifsson, Gudmar
    Willer, Cristen J
    Herrera, Blanca M
    Jackson, Anne U
    Lim, Noha
    Scheet, Paul
    Soranzo, Nicole
    Amin, Najaf
    Aulchenko, Yurii S
    Chambers, John C
    Drong, Alexander
    Luan, Jian'an
    Lyon, Helen N
    Rivadeneira, Fernando
    Sanna, Serena
    Timpson, Nicholas J
    Zillikens, M Carola
    Zhao, Jing Hua
    Almgren, Peter
    Bandinelli, Stefania
    Bennett, Amanda J
    Bergman, Richard N
    Bonnycastle, Lori L
    Bumpstead, Suzannah J
    Chanock, Stephen J
    Cherkas, Lynn
    Chines, Peter
    Coin, Lachlan
    Cooper, Cyrus
    Crawford, Gabriel
    Doering, Angela
    Dominiczak, Anna
    Doney, Alex S F
    Ebrahim, Shah
    Elliott, Paul
    Erdos, Michael R
    Estrada, Karol
    Ferrucci, Luigi
    Fischer, Guido
    Forouhi, Nita G
    Gieger, Christian
    Grallert, Harald
    Groves, Christopher J
    Grundy, Scott
    Guiducci, Candace
    Hadley, David
    Hamsten, Anders
    Havulinna, Aki S
    Hofman, Albert
    Holle, Rolf
    Holloway, John W
    Illig, Thomas
    Isomaa, Bo
    Jacobs, Leonie C
    Jameson, Karen
    Jousilahti, Pekka
    Karpe, Fredrik
    Kuusisto, Johanna
    Laitinen, Jaana
    Lathrop, G Mark
    Lawlor, Debbie A
    Mangino, Massimo
    McArdle, Wendy L
    Meitinger, Thomas
    Morken, Mario A
    Morris, Andrew P
    Munroe, Patricia
    Narisu, Narisu
    Nordström, Anna
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Sports Medicine. Umeå University, Faculty of Medicine, Department of Community Medicine and Rehabilitation, Geriatric Medicine.
    Nordström, Peter
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Sports Medicine. Umeå University, Faculty of Medicine, Department of Community Medicine and Rehabilitation, Geriatric Medicine.
    Oostra, Ben A
    Palmer, Colin N A
    Payne, Felicity
    Peden, John F
    Prokopenko, Inga
    Renström, Frida
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Medicine.
    Ruokonen, Aimo
    Salomaa, Veikko
    Sandhu, Manjinder S
    Scott, Laura J
    Scuteri, Angelo
    Silander, Kaisa
    Song, Kijoung
    Yuan, Xin
    Stringham, Heather M
    Swift, Amy J
    Tuomi, Tiinamaija
    Uda, Manuela
    Vollenweider, Peter
    Waeber, Gerard
    Wallace, Chris
    Walters, G Bragi
    Weedon, Michael N
    Witteman, Jacqueline C M
    Zhang, Cuilin
    Zhang, Weihua
    Caulfield, Mark J
    Collins, Francis S
    Davey Smith, George
    Day, Ian N M
    Franks, Paul W
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Medicine.
    Hattersley, Andrew T
    Hu, Frank B
    Jarvelin, Marjo-Riitta
    Kong, Augustine
    Kooner, Jaspal S
    Laakso, Markku
    Lakatta, Edward
    Mooser, Vincent
    Morris, Andrew D
    Peltonen, Leena
    Samani, Nilesh J
    Spector, Timothy D
    Strachan, David P
    Tanaka, Toshiko
    Tuomilehto, Jaakko
    Uitterlinden, André G
    van Duijn, Cornelia M
    Wareham, Nicholas J
    Hugh Watkins,
    Waterworth, Dawn M
    Boehnke, Michael
    Deloukas, Panos
    Groop, Leif
    Hunter, David J
    Thorsteinsdottir, Unnur
    Schlessinger, David
    Wichmann, H-Erich
    Frayling, Timothy M
    Abecasis, Gonçalo R
    Hirschhorn, Joel N
    Loos, Ruth J F
    Stefansson, Kari
    Mohlke, Karen L
    Barroso, Inês
    McCarthy, Mark I
    Genome-wide association scan meta-analysis identifies three Loci influencing adiposity and fat distribution.2009In: PLoS genetics, ISSN 1553-7404, Vol. 5, no 6, p. e1000508-Article in journal (Refereed)
    Abstract [en]

    To identify genetic loci influencing central obesity and fat distribution, we performed a meta-analysis of 16 genome-wide association studies (GWAS, N = 38,580) informative for adult waist circumference (WC) and waist-hip ratio (WHR). We selected 26 SNPs for follow-up, for which the evidence of association with measures of central adiposity (WC and/or WHR) was strong and disproportionate to that for overall adiposity or height. Follow-up studies in a maximum of 70,689 individuals identified two loci strongly associated with measures of central adiposity; these map near TFAP2B (WC, P = 1.9x10(-11)) and MSRA (WC, P = 8.9x10(-9)). A third locus, near LYPLAL1, was associated with WHR in women only (P = 2.6x10(-8)). The variants near TFAP2B appear to influence central adiposity through an effect on overall obesity/fat-mass, whereas LYPLAL1 displays a strong female-only association with fat distribution. By focusing on anthropometric measures of central obesity and fat distribution, we have identified three loci implicated in the regulation of human adiposity.

  • 254.
    Lindmark, Anna
    et al.
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Sports Medicine.
    Olsén, Anneli
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Sports Medicine.
    Hansson, Maribel
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Sports Medicine.
    Alternativa behandlingsformer vid Attention deficit hyperactivity disorder.2012Independent thesis Basic level (university diploma), 5 credits / 7,5 HE creditsStudent thesis
    Abstract [sv]

    Attention Deficit Hyperacticity Disorder (ADHD), är en neuropsykiatrisk sjukdom som finns hos både barn och vuxna och innebär svårigheter med uppmärksamhet, impulsivitet och överaktivitet. Behandling med mediciner kan ge oanade biverkningar och därför är syftet med denna litteraturstudie att beskriva hur alternativa behandlingsformer, så som fysisk aktivitet, massage och kostupplägg, kan underlätta vardagen för personer med ADHD. Denna litteraturstudie är en sammanfattning av tidigare studier gjorda inom ämnet. Utifrån resultatet är det konstaterat att det finns många alternativa behandlingar som i kombination med centralstimulantia fungerar bra genom att minska symtomen och därmed underlätta vardagen. Det finns ett stort intresse av alternativa behandlingar, dock behövs mer forskning inom området för att ta reda på om man kan använda sig av endast alternativa behandlingsformer. Spa-miljön kan vara en gynnsam miljö vid alternativa behandlingar av ADHD då alla behandlingar kan ske på samma ställe.  

  • 255. Ljung, Björn-Ove
    et al.
    Alfredson, Håkan
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Sports Medicine.
    Forsgren, Sture
    Umeå University, Faculty of Medicine, Department of Integrative Medical Biology (IMB), Anatomy.
    Neurokinin 1-receptors and sensory neuropeptides in tendon insertions at the medial and lateral epicondyles of the humerus. Studies on tennis elbow and medial epicondylalgia.2004In: Journal of Orthopaedic Research, ISSN 0736-0266, Vol. 22, no 2, p. 321-7Article in journal (Refereed)
    Abstract [en]

    There is no information on the sensory innervation at the flexor muscle origin at the medial epicondyle of the humerus and it is not known if substance P receptors (Neurokinin 1-receptors, NK1-R) are present in tendon insertions in general. In the present investigation, we have studied the muscle origin in patients suffering from medial epicondylalgia and tennis elbow. Immunohistochemistry and antibodies to substance P (SP) and CGRP as well as the general nerve marker PGP 9.5 were used. Specific immunoreactions were observed in nerve bundles and as free nerve fibers. The immunoreactive structures were partly seen in association with some of the blood vessels. The observations constitute a morphological correlate for the occurrence of nerve mediated effects in this region. By using immunohistochemistry and antibodies to NK1-R, the distribution of this receptor was studied at the insertion of the proximal tendon of the extensor carpi radialis brevis muscle at the lateral epicondyle. Specific immunoreactions were seen as varicose fibers occurring as single fibers or grouped into bundles, indicating that SP has effects in the nerves in this region. The results give further evidence for a possible neurogenic involvement in the pathophysiology of tennis elbow and in medial epicondylalgia.

  • 256.
    Lorentzon, Ronny
    et al.
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Sports Medicine.
    Alfredson, Håkan
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Sports Medicine.
    Hildingsson, Christer
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Orthopaedics.
    Treatment of deep cartilage defects of the patella with periosteal transplantation1998In: Knee Surgery, Sports Traumatology, Arthroscopy, ISSN 0942-2056, E-ISSN 1433-7347, Vol. 6, no 4, p. 202-208Article in journal (Refereed)
    Abstract [en]

    Twenty-six consecutive patients (19 men and 7 women) with a mean age of 31.5 years (range 19-52 years) who suffered from an isolated full-thickness cartilage defect of the patella (area ranged from 0.75 to 20.0 cm2) and disabling knee pain were treated with autologous periosteal transplantation (without any chondrocytes). The duration of symptoms was 59 months (range 11-144 months). During the first 5 postoperative days all patients were treated with continuous passive motion (CPM). This was followed by active motion, slowly progressive strength training, and slowly progressive weight-bearing. After a mean follow-up of 42 months (range 24-76 months), 17 patients (65%) were graded as excellent (were painfree), 8 patients (31%) as good (had pain with strenuous knee-loading activities), and 1 patient as poor (had pain at rest). Twenty-two patients (85%) had returned to their previous occupation. Twelve patients (46%) had resumed sports or recreational activities at their former level. Repeated magnetic resonance imaging (MRI) investigations showed progressive, and finally complete, filling of the articular defects. Biopsies taken in five randomly selected cases showed hyaline-like cartilage. Patients with full-thickness cartilage defects of the patella and disabling knee pain can be treated with autologous periosteal transplantation (without any chondrocytes), followed by CPM, and slowly progressive strength training and weight-bearing. We believe this is a good method to accomplish regeneration of articular cartilage and satisfactory clinical results.

  • 257.
    Lorentzon, Ronny
    et al.
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Sports Medicine.
    Nordström, Peter
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Sports Medicine.
    Pettersson, Ulrika
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Sports Medicine.
    The Achilles heel of exercise.2000In: The Lancet, ISSN 0140-6736, E-ISSN 1474-547X, Vol. 355, no 9218, p. 1909-10; author reply 1911Article in journal (Refereed)
  • 258.
    Lundin, Anton
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Sports Medicine.
    Jämförelse mellan hjärtfrekvensstyrd laktattröskelträning på löpband och inomhusbana med avseende på blodlaktat, löphastighet och upplevd ansträngning.2013Independent thesis Advanced level (degree of Master (One Year)), 20 credits / 30 HE creditsStudent thesis
    Abstract [sv]

    Bakgrund Laktattröskeltest för att fastställa den anaeroba laktattröskeln (AnT) vid löpning utförs i de flesta fall på löpband medan den största delen av träning och tävling utförs på fast underlag. För att kunna ge adekvata tränings- eller tävlingsrekommendationer baserat på AnT måste laktatnivån vid uppmätt arbetsintensitet vid AnT vara lika mellan underlagen. Utifrån detta perspektiv var syftet med den aktuella studien att jämföra upplevd ansträngningsgrad, hastighet, stegfrekvens (SF) och laktatnivå vid två tröskelträningspass, ett på fast underlag och det andra på löpband, där intensiteten styrdes efter hjärtfrekvensen (HF) vid AnT som fastställdes vid ett tröskeltest på löpband. Metod Sex vältränade långdistanslöpare, tre män och tre kvinnor (29.0 ± 6.3 år), genomförde två löpträningspass (5 x 1000m, 60 sekunder vila), ett på löpband och ett på en 200-meters inomhusbana. Intensiteten anpassades efter HF vid den individuella AnT (IAnT) som fastställdes genom ett laktattröskeltest på löpband. Innan start och efter varje intervall togs ett kapillärt blodlaktatprov och ansträngningsgraden självskattades av löparna med hjälp av Borg’s RPE-skala®. HF, hastighet och SF registrerades kontinuerligt med pulsklocka. Resultat Ingen signifikant skillnad i laktatnivå eller löphastighet upptäcktes men däremot var SF signifikant högre (p=0.015) på bana medan skattad ansträngningsgrad var högre på löpband (p=0.042). Löphastighet och blodlaktatnivåer sjönk på de senare intervallerna på båda underlagen. Slutsats Vältränade löpare visar ingen signifikant skillnad vad gäller blodlaktatnivå eller hastighet mellan intervallträning på ett löpband och en inomhusbana när intensiteten styrs utifrån uppmätt HF vid IAnT-test på löpband. Vid laktattröskelträning styrd efter HF måste ökad HF tillåtas i en senare del av passet för att inte träningsbelastningen ska sjunka.

  • 259.
    Mafi, Nader
    et al.
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Sports Medicine.
    Lorentzon, Ronny
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Sports Medicine.
    Alfredson, Håkan
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Sports Medicine.
    Superior short-term results with eccentric calf muscle training compared to concentric training in a randomized prospective multicenter study on patients with chronic Achilles tendinosis.2001In: Knee Surgery, Sports Traumatology, Arthroscopy, ISSN 0942-2056, E-ISSN 1433-7347, Vol. 9, no 1, p. 42-47Article in journal (Refereed)
    Abstract [en]

    In a previous uncontrolled pilot study we demonstrated very good clinical results with eccentric calf muscle training on patients with painful chronic Achilles tendinosis located at the 2-6 cm level in the tendon. In the present prospective multicenter study (Sundsvall and Umeå) patients with painful chronic Achilles tendinosis at the 2-6 cm level in the tendon were randomized to treatment with either an eccentric or a concentric training regimen for the calf muscles. The study included 44 patients, with 22 patients (12 men, 10 women; mean age 48 years) in each treatment group. The amount of pain during activity (jogging or walking) was recorded by the patients on a visual analogue scale, and patient satisfaction was assessed before and after treatment. The patients were instructed to perform their eccentric or concentric training regimen on a daily basis for 12 weeks. In both types of treatment regimen the patients were told to do their exercises despite experiencing pain or discomfort in the tendon during exercise. The results showed that after the eccentric training regimen 82% of the patients (18/22) were satisfied and had resumed their previous activity level (before injury), compared to 36% of the patients (8/22) who were treated with the concentric training regimen. The results after treatment with eccentric training was significantly better (P<0.002) than after concentric training. The good clinical results previously demonstrated in the pilot study with eccentric calf muscle training on patients with chronic Achilles tendinosis, were thus reproduced in this multicenter, showing superior results to treatment with concentric training.

  • 260. Malm, C
    et al.
    Svensson, M
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Sports Medicine.
    Ekblom, B
    Sjödin, B
    Effects of ubiquinone-10 supplementation and high intensity training on physical performance in humans.1997In: Acta Physiologica Scandinavica, ISSN 0001-6772, E-ISSN 1365-201X, Vol. 161, no 3, p. 379-84Article in journal (Refereed)
    Abstract [en]

    This study investigated the effects of oral supplementation with ubiquinone-10 (Q10) (n = 9) compared with a placebo (n = 9) on aerobic and anaerobic physical performance over 22 days of supplementation. The supplementation period included 5 days of high intensity anaerobic training between days 11 and 14. The results demonstrated, that on an anaerobic (10 x 10 s) cycling test, the placebo group showed a significantly greater improvement than the Q10-group after a supplementation and training period (P < 0.001). Further, the Q10 group had a significantly lower increase in total work performed during the seven training sessions (15 x 10 s) compared with the placebo group (P < 0.001). There was a significant increase in maximal blood lactate accumulation during cycling in the both groups, when compared with levels before the training and recovery period. There was no significant difference between the groups, either in VO2max determined during running, or in submaximal and peak VO2, Rate of Perceived Exertion, respiratory quotient, blood lactate concentration or heart rate determined during submaximal and maximal cycling. Although insignificant (P = 0.1-0.3), there was evidence of higher submaximal VO2 (55-80% of VO2peak) during cycling in the Q10-group compared with the placebo group after training and recovery. It is concluded that with high intensity anaerobic training, there was a significantly greater increase in anaerobic performance in the placebo group compared with the Q10 group. The results suggest less increase in physical performance with Q10 supplement and high intensity anaerobic training, compared with placebo.

  • 261. Malm, C
    et al.
    Svensson, M
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Sports Medicine.
    Sjöberg, B
    Ekblom, B
    Sjödin, B
    Supplementation with ubiquinone-10 causes cellular damage during intense exercise.1996In: Acta Physiologica Scandinavica, ISSN 0001-6772, E-ISSN 1365-201X, Vol. 157, no 4, p. 511-2Article in journal (Refereed)
  • 262.
    Malm, Christer
    et al.
    Umeå University, Faculty of Medicine, Department of Integrative Medical Biology (IMB).
    Hadrevi, Jenny
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Sports Medicine.
    Bergström, Sven-Anders
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Medicine.
    Pedrosa-Domellof, Fatima
    Umeå University, Faculty of Medicine, Department of Integrative Medical Biology (IMB). Umeå University, Faculty of Medicine, Department of Clinical Sciences, Ophthalmology.
    Antti, Henrik
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Svensson, Michael
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Sports Medicine.
    Frängsmyr, Lars
    Umeå University, Faculty of Medicine, Department of Integrative Medical Biology (IMB).
    Evaluation of 2-D DIGE for skeletal muscle: Protocol and repeatability2008In: The Scandinavian Journal of Clinical & Laboratory Investigation, Vol. 68, no 8, p. 793-800Article in journal (Refereed)
    Abstract [en]

    Proteomic analysis has the potential to yield vast amounts of data. The available proteomic methods have been hampered by methodological errors in quantification due to large gel-to-gel variations. The inclusion of an internal standard greatly reduces this variation, and therefore the purpose of this investigation was: 1) to develop a sample preparation protocol for human skeletal muscle for two-dimensional differentiated gel electrophoresis (DIGE) and 2) to investigate the repeatability of one particular system, the Ettan™ DIGE. To test repeatability, nine aliquots from the same homogenate were labelled with three different CyDye™ dyes (Cy2, Cy3, Cy5). Samples were run on 1824 cm gels, scanned with a Typhoon™ 9410 laser scanner and analysed in the DeCyder™ software. When selecting spots appearing only in triplicate (n = 1314), the mean error was 1.7 % (SD: 10.5 %; 95 % CI: 1.1-2.4 %). When setting the significance level to 99 %, no false-positive changes in protein volume ratios were detected. In the protocol presented here, only 0.5 mg tissue was used and separation of >2500 distinct protein spots in the pH range 3-11 and MW 10-200 kDa. Changes in protein abundance of <20 % could be detected. The method is especially useful when comparing muscle proteins between different conditions; for example, healthy and diseased tissue, before and after treatment or different exercise protocols.

  • 263.
    Malm, Christer
    et al.
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Sports Medicine. Umeå University, Faculty of Medicine, Department of Integrative Medical Biology (IMB), Anatomy.
    Yu, Ji-Guo
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Sports Medicine. Umeå University, Faculty of Medicine, Department of Integrative Medical Biology (IMB), Anatomy.
    Exercise-induced muscle damage and inflammation: re-evaluation by proteomics2012In: Histochemistry and Cell Biology, ISSN 0948-6143, E-ISSN 1432-119X, Vol. 138, no 1, p. 89-99Article in journal (Refereed)
    Abstract [en]

    Using proteomics combined with immunohistochemistry (IHC), we re-evaluated our previous hypothesis that voluntary eccentric exercise does not result in inflammation or necrosis while it does lead to muscular adaptation/remodeling through Z-band related proteins. Muscle biopsies from m. vastus lateralis were taken from five control and five exercised subjects 48 h after 45 min of downhill running. General muscle morphology was examined using histology and histochemistry. Proteomics was used to reveal protein profiles and novel proteins. IHC with specific antibody against three Z-band related proteins identified by proteomics was also performed. General morphology showed no muscle degeneration or inflammation in any exercised biopsy. Proteomics revealed that out of 612 individual protein spots, the exercised biopsy presented three proteins with significant (p < 0.05) higher expression ratio and four proteins of lower ratio compared to controls. Four of the proteins desmin, actin, Rab-35 and LDB3 are Z-band related; the former two have long been the focus of interest and were found to be up-regulated in the study; the latter two are Z-band assembly/stabilization protein and were for the first time observed to be down-regulated in exercised muscles. The other three proteins are related with either cellular metabolism or calcium homeostasis and none is related with muscle necrosis or inflammation. IHC observations that both desmin and actin were increased whereas LDB3 was completely absent in some focal areas are consistent with proteomic results and with our previous observations. The results of the study confirmed our previous findings and therefore strengthened the hypothesis that voluntary eccentric exercise does not cause human muscle necrosis or inflammation; instead, muscular remodeling occurs specifically through Z-band related proteins.

  • 264.
    Malmgren, Evelina
    et al.
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Sports Medicine.
    Ingelsson, Frida
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Sports Medicine.
    Ohlsson, Annica
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Sports Medicine.
    Low carb high fat: Passar det normalviktiga?2012Independent thesis Basic level (university diploma), 5 credits / 7,5 HE creditsStudent thesis
    Abstract [sv]

    Low Carb High Fat (LCHF) ses som en striktare variant av GI eller Atkins och är en diet riktad framförallt till personer som lider av det metabola syndromet, där man utesluter i princip alla kolhydrater för att undvika blodsockerhöjningar. Överviktiga och diabetiker som testat denna diet har både fått bättre blodfetter, viktnedgång samt ett förbättrat blodsocker men samtidigt finns det många motsträvare – framförallt SNR (svenska näringsrekommendationer). Syftet med detta projekt var att visa effekterna hos friska, normalviktiga personer som genomgått en tre veckors dietperiod med LCHF kost. Hur vikten, blodfetterna samt det psykiska har påverkats. Resultatet har visat på att vikten har minskat samt att blodfetterna höjts avsevärt, vilket ger ett svar på att LCHF inte passar normalviktiga.

  • 265.
    Markström, Jonas
    et al.
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Sports Medicine.
    Olsson, Carl-Johan
    Umeå University, Faculty of Social Sciences, Centre for Population Studies (CPS).
    Countermovement jump peak force relative to body weight and jump height as predictors for sprint running performances: (in)homogeneity of track and field athletes?2013In: Journal of Strength and Conditioning Research, ISSN 1064-8011, E-ISSN 1533-4287, Vol. 27, no 4, p. 944-953Article in journal (Refereed)
    Abstract [en]

    The purpose of this study was to investigate: (1) If variables from one-leg drop jump (DJ), DJ, squat jump (SJ), and counter movement jump (CMJ) tests can predict sprint performances for sprinters. (2) If sprinters and jumpers can be distinguished based on variables from one-leg DJ, DJ, SJ, and CMJ tests, also if sprinters and throwers can be distinguished based on variables from stiff leg jump (SLJ), SJ, and CMJ tests. A single linear regression and multiple linear regression analysis approach with models including two or three variables were used when predicting sprint performances. Five elite sprinters (1 female) participated in the first subexamination and five sprinters (1 female) vs five jumpers and six sprinters vs. six throwers (4 females) participated in the second. The force variable CMJ peak force relative to body weight significantly predicted the sprint performances maximal running velocity through 10 m (Vmax10m) and 60 m time. Vmax10m was also predicted by CMJ height. Jump heights from SJ and DJ did not predict sprint performances. The between group analysis of the athletes showed a non-significant group difference with respect to the jump variables. However, planned comparisons between sprinters and throwers showed significant differences on a number of SLJ variables. When constructing training programs for sprinters, aim should be to improve CMJ peak force and CMJ height because of the prediction of Vmax10m and 60 m time, presumably due to velocity specificity components.

  • 266.
    Martin, Fahlström
    et al.
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Sports Medicine. Umeå University, Faculty of Medicine, Department of Community Medicine and Rehabilitation, Rehabilitation Medicine. Umeå University, Faculty of Medicine, Department of Clinical Sciences, Professionell Development.
    Fahlström, P G
    Lorentzon, Ronny
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Sports Medicine.
    Henriksson-Larsén, Karin
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Sports Medicine.
    Positive short-term subjective effect of sports drink supplementation during recovery.2006In: J Sports Med Phys Fitness, ISSN 0022-4707, Vol. 46, no 4, p. 578-84Article in journal (Refereed)
  • 267.
    Michaelson, Peter
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Sports Medicine.
    Sensorimotor characteristics in chronic neck pain: possible pathophysiological mechanisms and implications for rehabilitation2004Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Pain from the musculoskeletal system is very common in the modern society. Chronic musculoskeletal pain syndromes causes not only individual suffering but also dysfunctions of movements and postural control, as large costs for the society. In spite of significant efforts, there is a shortage of knowledge on effective prevention, diagnoses and rehabilitation of different chronic musculoskeletal pain syndromes.

    The general aims of this thesis was to investigate the predictive value of physical, sociodemographic, and psychosocial-behavioural variables for pain reduction after multimodal rehabilitation in patients with chronic low back or neck pain, and to develop and evaluate tests for objective and quantitative evaluation of characteristic sensorimotor disturbances in chronic neck pain.

    Logistic regression models revealed that unchanged pain intensity could be predicted with good precision while reduced pain intensity after rehabilitation was poorly predicted by the baseline variables. Altered pain intensity in chronic low back pain was predicted by high pain intensity, low levels of pain severity and high affective distress, while reduced pain intensity for patients with chronic neck pain were predicted by high endurance, low age, high pain intensity, low need of being social along with optimistic attitudes on how the pain will interfere with daily life, and few vegetative symptoms. One of the conclusions was that objective measures of specific sensorimotor disturbances should improve the precision by which treatment-induced effects can be assessed and predicted.

    A study was designed to objectively and quantitatively evaluate a large numbers of different sensorimotor characteristics in a small group of patients with chronic neck pain of different aetiology (whiplash-related and insidious). Kinematic data was recorded during different motor tasks, involving cervical rotations, arm movements and standing. In comparison to a group of asymptomatic control subjects, patients with chronic neck pain was characterised by slower movements, poor balance, reduced cervical stability during perturbations, altered smoothness of movement (jerk index), and reduced movement precision (variable error and variability in range of motion). The sensorimotor variables velocity of arm movements and cervical stability, could correctly classified nearly 90% of the subjects as having chronic neck pain or being asymptomatic.

    There was a large diversity of sensorimotor disturbances among the individual patients. This was confirmed in a regression model that failed to separate the groups insidious neck pain (sensitivity 44%) and WAD (sensitivity 67%).

    By investigating associations between the different sensorimotor variables, close relations was found between the repositioning acuity and variability in range of motion, and between standing balance and cervical stability/ standing balance during perturbation. These two groups of variables were only weakly related to each other and to smoothness of movement and movement velocity.

    The results indicate that chronic neck pain is characterised by specific sensorimotor deficits, and that there are common pathophysiological mechanisms in chronic neck pain of different aetiology. However, the lack of associations between several sensorimotor disturbances indicates that different mechanisms are involved. The thesis indicates that objective sensorimotor tests should be used to improve the quality of functional assessments in chronic neck pain. Methods that objectively and quantitatively measure e.g. movement precision, balance and cervical stability are also needed in order to evaluate current treatment methods and to develop new rehabilitation programs for specific sensorimotor deficits.

  • 268.
    Michaelson, Peter
    et al.
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Sports Medicine.
    Michaelson, M
    Jaric, S
    Latash, ML
    Sjölander, P
    Djupsjöbacka, M
    Vertical posture and head stability in patients with chronic neck pain.2003In: Journal of Rehabilitation Medicine, ISSN 1650-1977, E-ISSN 1651-2081, Vol. 35, no 5, p. 229-235Article in journal (Refereed)
    Abstract [en]

    OBJECTIVE: To evaluate postural performance and head stabilization of patients with chronic neck pain. DESIGN: A single-blind comparative group study. SUBJECTS: Patients with work-related chronic neck pain (n = 9), with chronic whiplash associated disorders (n = 9) and healthy subjects (n = 16). METHODS: During quiet standing in different conditions (e.g. 1 and 2 feet standing, tandem standing, and open and closed eyes) the sway areas and the ability to maintain the postures were measured. The maximal peak-to-peak displacement of the centre of pressure and the head translation were analysed during predictable and unpredictable postural perturbations. RESULTS: Patients with chronic neck pain, in particular those with whiplash-associated disorders, showed larger sway areas and reduced ability to successfully execute more challenging balance tasks. They also displayed larger sway areas and reduced head stability during perturbations. CONCLUSION: The results show that disturbances of postural control in chronic neck pain are dependent on the aetiology, and that it is possible to quantify characteristic postural disturbances in different neck pain conditions. It is suggested that the dissimilarities in postural performance are a reflection of different degrees of disturbances of the proprioceptive input to the central nervous system and/or of the central processing of such input.

  • 269.
    Michaelson, Peter
    et al.
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Sports Medicine.
    Sjölander, Per
    Johansson, Håkan
    Factors predicting pain reduction in chronic back and neck pain after multimodal treatment.2004In: The Clinical Journal of Pain, ISSN 0749-8047, E-ISSN 1536-5409, Vol. 20, no 6, p. 447-454Article in journal (Refereed)
    Abstract [en]

    OBJECTIVES: To determine whether treatment related pain reduction on the short- and long-term is predicted by different baseline variables, and with different accuracy, in patients with chronic low back pain as compared with those with chronic neck pain. DESIGN AND METHODS: A single blinded prospective cohort study based on patients with chronic musculoskeletal pain in the lower back (N = 167) or the neck (N = 136) who completed a 4-week multimodal rehabilitation program. At admission, each patient was evaluated on 17 potential predictors, including pain characteristics and physical, sociodemographic, and psychosocial-behavioral variables. Changes in self-reported pain intensity in the lower back or the neck between the pretreatment evaluation and those performed immediately after, and 12 months after the rehabilitation program, were assessed. RESULTS: Logistic regression models revealed that change in pain intensity could be predicted with good specificity but with poor sensitivity both for patients with chronic low back pain and chronic neck pain. Significant predictors among the neck pain patients were high endurance, low age, high pain intensity, few other symptoms, low need of being social, to do things with others, and to be helped, along with optimistic attitudes on how the pain will interfere with daily life. Among the low back pain patients, high pain intensity, low levels of pain severity, and high affective distress were important predictors. Variables such as sex, sick leave history, working status, accident, pain duration, and depressive symptoms demonstrated no predictive value. Short- and long-term pain outcome was equally predictable and predicted by almost the same variables. CONCLUSIONS: Patients who reported unchanged or increased pain after multimodal treatment could be predicted with good accuracy, whereas those who reported decreased pain were more difficult to identify. Treatment-related pain alteration in chronic low back pain seems to be predicted by partly different variables than in chronic neck pain.

  • 270. Michaëlsson, Karl
    et al.
    Nordström, Peter
    Umeå University, Faculty of Medicine, Department of Community Medicine and Rehabilitation, Geriatric Medicine.
    Nordström, Anna
    Umeå University, Faculty of Medicine, Department of Community Medicine and Rehabilitation, Rehabilitation Medicine. Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Sports Medicine. Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Occupational and Environmental Medicine.
    Garmo, Hans
    Byberg, Liisa
    Pedersen, Nancy L
    Melhus, Håkan
    Impact of hip fracture on mortality: a cohort study in hip fracture discordant identical twins2014In: Journal of Bone and Mineral Research, ISSN 0884-0431, E-ISSN 1523-4681, Vol. 29, no 2, p. 424-431Article in journal (Refereed)
    Abstract [en]

    Several studies have shown a long-lasting higher mortality after hip fracture but the reasons of the excess risk is not well understood. We aimed to determine whether there exists a higher mortality after hip fracture when controlling for genetic constitution, shared environment, comorbidity and lifestyle by use of a nation-wide cohort study in hip fracture discordant monozygotic twins. All 286 identical Swedish twin pairs discordant for hip fracture (1972-2010) were identified. Comorbidity and lifestyle information was retrieved by registers and questionnaire information. We used intrapair Cox regression to compute multivariable-adjusted hazard ratios (HRs) for death. During follow-up, 143 twins with a hip fracture died (50%) compared to 101 twins (35%) without a hip fracture. Through the first year after hip fracture, the rate of death increased four-fold in women (HR 3.71; 95% confidence interval (CI) 1.32-10.40) and seven-fold in men (HR 6.67; 95% CI 1.47-30.13). The increased rate in women only persisted during the first year after hip fracture (HR after 1 year 0.99; 95% CI 0.66-1.50), whereas the corresponding HR in men was 2.58 (95% CI 1.02-6.62). The higher risk in men after the hip fracture event was successively attenuated during follow-up. After 5 years, the hazard ratio in men with a hip fracture was 1.19 (95% CI 0.29-4.90). On average, the hip fracture contributed to 0.9 years of life lost in women (95% CI 0.06-1.7) and 2.7 years in men (95% CI 1.7-3.7). The potential years of life lost associated with the hip fracture was especially pronounced in older men (>75 years), with an average loss of 47% (95% CI 31-61) of the expected remaining lifetime. We conclude that both women and men display a higher mortality after hip fracture independent of genes, comorbidity and lifestyle.

  • 271.
    Nilsson, Robert
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Sports Medicine.
    Physical demands of alpine skiing: Correlations between physical tests and sport-specific performance2013Independent thesis Advanced level (degree of Master (One Year)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Alpine skiing is considered to be the world's fastest non-motorized sport and is one of the most popular leisure activities among children and adolescents in many alpine countries. Competitive alpine skiing itself is a generic term for six different disciplines which all differ from each other in terms of turning radius, distance between gates, speed and course length. In order to be successful in this sport, practitioners must therefore consider a wide range of physical abilities during their preparatory training. Since previous studies have shown a correlation between international successes in alpine skiing and different physical part qualities, testing these qualities are therefore essential. Thus, in order to monitor their athlete’s physical status, the Swedish national alpine ski team conducts at least two mandatory tests annually using a test protocol called Fysprofilen. The questions are, however, if this is an adequate test protocol for alpine skiers and if the athlete's sport-specific performance can be predicted using this test battery. Results from Fysprofilen tests between the years 2006-2012 from 12 female world-class Swedish professional skiers were correlated to their Fédération Internationale de Ski (FIS) points at the time of testing and analyzed using linear, stepwise multiple regression. Significant regression models were found for all disciplines; slalom (SL; R2 = 0.68 with body weight), giant slalom (GS; R2=0.20 with body height and weight), super giant slalom (SG; R2=0.35 with body height and weight), downhill (DH; R2=0.19 with body height) and super combined (SC; R2=0.21 with grip strength). The author concludes that conducted physical tests fail to give the practitioner, trainers and leaders a reliable indication of the sport-specific performance of an alpine skier.

  • 272.
    Nilsson, Stefan
    et al.
    Umeå University, Faculty of Medicine, Department of Community Medicine and Rehabilitation, Rehabilitation Medicine.
    Levi, Richard
    Umeå University, Faculty of Medicine, Department of Community Medicine and Rehabilitation, Rehabilitation Medicine.
    Nordström, Anna
    Umeå University, Faculty of Medicine, Department of Community Medicine and Rehabilitation, Rehabilitation Medicine. Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Sports Medicine.
    Treatment-resistant sensory motor symptoms in persons with SCI may be signs of restless legs syndrome2011In: Spinal Cord, ISSN 1362-4393, E-ISSN 1476-5624, Vol. 49, no 6, p. 754-756Article in journal (Refereed)
    Abstract [en]

    Study design: Case report on the successful treatment with pramipexole in four men with chronic spinal cord injury (SCI) suffering from refractory symptoms that were previously considered to be manifestations of a post-traumatic spastic syndrome or neuropathic pain.

    Objective: To raise awareness among health professionals regarding the diagnostic and therapeutic possibility of restless legs syndrome (RLS) and periodic limb movements (PLMs) in some patients with SCI responding poorly to conventional treatment for spasticity or neuropathic pain.

    Setting: Neurorehabilitation department of the Rehabilitation Medicine Center of Northern University Hospital, Umeå, Sweden.

    Methods: Medical records and clinical data were retrospectively reviewed.

    Results: All cases obtained treatment with pramipexole, initially 0.09–0.72 mg day−1. Two of the cases had RLS and PLMs, one RLS only and one PLMs only. All four reported symptoms in the lower extremities and one also in the upper extremities. Three patients with residual gait function reported RLS score with/without treatment as follows: 32/11, 37/12 and 33/12. One patient with complete paraplegia (with incomplete RLS score) reported 22/10. After a follow-up period of 16, 20, 43 and 49 months, respectively, all four still reported excellent outcomes. Two remained on initial dosage; one had increased dosage from 0.09 to 0.18 mg day−1 and one from 0.27 to 0.80 mg day−1 during the follow-up period.

    Conclusions: In persons with SCI suffering from infralesional involuntary movements and/or dysesthesia and with poor response to conventional antispastic or analgesic treatment, the possibility of RLS or PLMs should be considered, as these conditions seem eminently treatable.

  • 273.
    Nordeborn, Jakob
    et al.
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Sports Medicine.
    Holsten, Tobias
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Sports Medicine.
    Hamstringskador inom olika idrotter: Skadefrekvens, bakomliggande faktorer, uppkomst och prevention2013Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The hamstring muscle complex is one of the most frequently injured muscle groups in sports. Most previous studies on the subject have examined injury frequency, localization, prevention and risk factors in a specific sport, though often separately. To date, few studies have examined and compared those factors between different sports. Therefore, the aim of this study is to examine the frequency of hamstring injury, potential mechanisms, risk factors and prevention methods in different sports.

    The highest frequency of hamstring injuries was found in gaelic football, european football, australian football, track and field, ballet and cheerleading. The most commonly injured muscle was the m. biceps femoris, mainly found in sports involving sprint movements. However, in sports such as ballet and cheerleading, involving slow stretching movements, hamstring injury involves mostly the m. semimembranosus and m. semitendinosus.

    The hamstring muscles are activated through the whole gait cycle, with the highest activation for m. biceps femoris at the end of the swingphase. This is believed to be the main cause of hamstring injuries, combined with a peak eccentric contraction force at the end of the swingphase.

    Other risk factors for hamstring injuries are age, hamstring-quadriceps strength ratio and fatigue, among others.

    Well performed warm-up and eccentric resistance training are preferable prevention methods.

    In conclusion, hamstring injury is common in sports involving high speed or over stretch. Increased muscle strength and strength balance between hamstring muscle and its antagonist seems to be an important factor in injury prevention.

     

    Key Words:  hamstring muscle complex; injuries; biomechanics; prevention; prevalence.

  • 274.
    Nordstrom, Anna
    et al.
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Sports Medicine.
    Hogstrom, Magnus
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Sports Medicine.
    Nordstrom, Peter
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Sports Medicine.
    Effects of different types of weight-bearing loading on bone mass and size in young males: a longitudinal studyManuscript (Other (popular science, discussion, etc.))
  • 275.
    Nordström, Anna
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Sports Medicine.
    An exercise in death notification2011In: Medical Education, ISSN 0308-0110, E-ISSN 1365-2923, Vol. 45, no 11, p. 1139-1140Article in journal (Refereed)
  • 276.
    Nordström, Anna
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Medicine. Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Sports Medicine. Umeå University, Faculty of Medicine, Department of Community Medicine and Rehabilitation, Geriatric Medicine.
    Bone mass and physical activity2004Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Abstract

    Weak and osteoporotic bones in old age are an increasing cause of mortality and painful physical impairment of the elderly, especially in the western world. Bone mineral accrual during childhood and adolescence is thought to play a vital role in preventing osteoporosis. Identifying and optimizing the factors influencing peak bone mass is thus important for the prevention of osteoporosis and related fractures.

    A main aim of this thesis was to investigate the potential effects of various types of weight-bearing physical activity on bone accretion in young males just out of puberty. The results from our subgroups of athletes consisting of badminton, ice hockey, and soccer players suggest that weight-bearing physical activity gives rise to regional specific bone response that is determined by the degree of impact of the activity in areas subject to mechanical loading (papers I–IV). In summary, the bone is sensitive to loading after puberty in males, and important bone mass gains can be achieved by proper amount and type of exercise.

    Another aim of this thesis was to studythe effect of detraining on weight-bearing and non-weight-bearing bone in a cohort of adolescent males who participated in ice hockey and soccer training. Our results indicate that exercise-induced bone mineral density benefits decline, predominantly in weight-bearing bones, after retirement from an active sports career (papers II–IV). High bone density stemming from physical loading might be at least partly preserved even by reduced physical activity at nonweight-bearing sites after about three years of reduced activity (III, IV).

    A final aim was to follow prospectively the development of BMD during years of reduced activity in former male athletes, and evaluate whether exercise during adolescence could be associated with fewer fractures in old age. We found fewer fragility fractures in a cohort of 400 former athletes compared to in 800 age-matched controls. Thus, high bone density stemming from previous weight-bearing physical activity may reduce the risk of sustaining fragility fractures in the elderly.

    Key words: physical activity, peak bone mineral density, males.

  • 277.
    Nordström, Anna
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Sports Medicine.
    Maratondöden: ett handledarperspektiv2010In: Undervisning på tvären - Student- och lärarerfarenheter: Den nionde universitetspedagogiska konferensen 25-26 februari 2009 : Konferensrapport / [ed] Erik Lindenius, Umeå Universitet: Universitetspedagogiskt centrum , 2010, p. 105-128Conference paper (Other academic)
    Abstract [sv]

    Ett av de svåra områdena inom läkarrollen är att ge svåra besked. Maratondöden är ett inlärningstillfälle baserat på forumspel som möjliggör för blivande läkare på läkarprogrammet att få öva sig i att ge ett dödsbesked. Övningsscenariot baseras på att handledaren i en grupp om 8–9 studenter spelar anhörig och sitter i ett väntrum på akuten. Läkarstudenternas uppgift är att i rollen som ansvarig läkare kommunicera att maken/makan till den oförberedde anhörige har dött oväntat. Handledaren spelar ut sin oro och sorg så realistiskt som möjligt. Samtliga studenter utför samma övning i enrum. Öv­ningarna som tar någon minut i anspråk per student, spelas in på vi­deo spelas sedan upp inför gruppen när alla har genomgått övning­en. Studenterna får feedback från medstudenter samt handledare och studenten som agerat läkare får inför gruppen reflektera över sig själv i den spelade situationen. Övningen sker termin 8 på ett inter­nat där bemötande och samtalsteknik står i fokus. Syftet med studien är att utvärdera forumspel som analyseras genom videoplaybackteknik som inlärningsmoment för att läm­na svåra besked. Semikvalitativ intervjuteknik användes för att utvärdera forum­spelsövningen Maratondöden. Teman som avhandlades var bak­grund, själva övningen samt resultat av övningen. Frågorna var standardiserade men öppna, några svarsalternativ fanns inte. Inter­vjuerna spelades in och därefter gjordes ordagranna utskrifter av in­tervjuerna. Genomläsningarna av utskrifterna samt efterföljande diskussioner kom att ligga till grund för analysen. Enkät inför samt efter utbildningsmomentet delades ut till samtliga 85 läkarstudenter som genomgick övningen under höstterminen 2008. Samtliga 10 studenter som valdes ut för intervjuerna – baserat på önskan att få ett så heterogent material som möjligt med avseende på kön, ålder samt nationalitet – accepterade och genomförde intervjuerna. Övningen uppfattades som laddad, realistisk och värdefull in­för den kommande yrkesrollen. Att för första gången tala om för någon att en närstående har avlidit upplevdes som svårt. Övning­en framkallade allt från positiv förväntan inför ett tävlingsmoment till ren ångest. Att genomgå övningen kändes som ett viktigt inlär­ningsmoment, att veta att de klarade av att genomföra situationen. Något som förstärkte övningen var återkopplingen i form av att se videon samt att få feedback från kurskamrater och handledare. Även att få se andra studenters rollspel och reflektera över skillna­der och likheter upplevdes som ett förstärkningsmoment, en möj­lighet att få se flera olika sätt. Den genomgående reflektionen var att studenterna efteråt kän­de sig mer förberedda på att ge ett svårt besked i verkligheten. An­dra reflektioner som framträdde var; bra första erfarenhet, större trygghet i situationen. Dock poängterades att detta var endast en kort övning och mer övning i ämnet efterfrågades. Maratondöden är ett användbart inlärningsmoment baserat på forumspel som möjliggör att studenten får öva sig i att ge ett svårt besked. Övningen uppfattades som ett bra inlärningstillfälle som gav möjlighet till träning för studenten att vara så trygga och pro­fessionella som möjligt i mötet med närstående. Att kunna få öva under så verklighetstrogna förutsättningar som möjligt bidrar till att studenterna är mer rustade inför sitt första svåra besked – i den framtida kliniska verkligheten.

  • 278.
    Nordström, Anna
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Sports Medicine.
    Upp och hoppa! Rörelse skyddar skelettet under hela livet.2009In: Svensk Idrottsmedicin, ISSN 1103-7652, no 2, p. 12-15Article in journal (Other academic)
  • 279.
    Nordström, Anna
    et al.
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Sports Medicine. Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Occupational and Environmental Medicine.
    Bredemo, Claes
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Sports Medicine.
    Tervo, Taru
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Sports Medicine.
    Bättre sprintförmåga med ny träningsmodell2013In: Svensk Idrottsforskning: Organ för Centrum för Idrottsforskning, ISSN 1103-4629, Vol. 22, no 4, p. 28-31Article in journal (Other academic)
    Abstract [sv]

    Innebandy är en sport fylld med högintensiva löpningar som ställer krav på både snabbhet och uthållighet. Förmågan att kunna upprepa många sprintlöpningar går att förbättra med särskild träning. Därför finns nu för första gången en träningsmodell anpassad för innebandy.

  • 280.
    Nordström, Anna
    et al.
    Umeå University, Faculty of Medicine, Department of Community Medicine and Rehabilitation, Rehabilitation Medicine. Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Sports Medicine.
    Edin, Benoni B.
    Umeå University, Faculty of Medicine, Department of Integrative Medical Biology (IMB), Physiology.
    Lindström, Sara
    Nordström, Peter
    Umeå University, Faculty of Medicine, Department of Community Medicine and Rehabilitation, Geriatric Medicine.
    Cognitive function and other risk factors for mild traumatic brain injury in young men: nationwide cohort study2013In: BMJ. British Medical Journal, E-ISSN 1756-1833, Vol. 346, p. f723-Article in journal (Refereed)
    Abstract [en]

    Objective To investigate cognitive function and other risk factors for mild traumatic brain injury in young men.

    Design Nationwide prospective cohort study.

    Setting Sweden.

    Participants 305 885 men conscripted for military service from 1989 to 1994.

    Main outcome measure mild traumatic brain injuries in relation to cognitive function and other potential risk factors assessed at conscription and follow-up.

    Results Men with one mild traumatic brain injury within two years before (n=1988) or after cognitive testing (n=2214) had about 5.5% lower overall cognitive function scores than did men with no mild traumatic brain injury during follow up (P<0.001 for both). Moreover, men with at least two mild traumatic brain injuries after cognitive testing (n=795) had 15% lower overall cognitive function scores compared with those with no such injury (P<0.001). Independent strong risk factors (P<1x10(-10)) for at least one mild traumatic brain injury after cognitive testing (n=12 494 events) included low overall cognitive function, a previous mild traumatic brain injury, hospital admission for intoxications, and low education and socioeconomic status. In a sub-cohort of twin pairs in which one twin had a mild traumatic brain injury before cognitive testing (n=63), both twins had lower logical performance and technical performance compared with men in the total cohort with no mild traumatic brain injury (P<0.05 for all).

    Conclusion Low cognitive function, intoxications, and factors related to low socioeconomic status were strong independent risk factors for mild traumatic brain injuries in men. The low cognitive function in twin pairs discordant for mild traumatic brain injury suggests a genetic component to the low cognitive function associated with such injuries. The study included only men, so inferences to women should be made with caution.

  • 281.
    Nordström, Anna
    et al.
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Sports Medicine.
    Eriksson, Marie
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Medicine.
    Stegmayr, Birgitta
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Medicine.
    Gustafson, Yngve
    Umeå University, Faculty of Medicine, Department of Community Medicine and Rehabilitation, Geriatric Medicine.
    Nordström, Peter
    Umeå University, Faculty of Medicine, Department of Community Medicine and Rehabilitation, Geriatric Medicine.
    Low bone mineral density is an independent risk factor for stroke and death2010In: Cerebrovascular Diseases, ISSN 1015-9770, E-ISSN 1421-9786, Vol. 29, no 2, p. 130-136Article in journal (Refereed)
    Abstract [en]

    We found that decreased BMD as well as osteoporosis of the femoral neck are independently associated with stroke and death. Given the impact of osteoporosis and stroke on morbidity and mortality, this relationship is of high interest for further studies.

  • 282.
    Nordström, Anna
    et al.
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Sports Medicine.
    Fjellman-Wiklund, Anncristine
    Umeå University, Faculty of Medicine, Department of Community Medicine and Rehabilitation.
    Grysell, Tomas
    Drama as a pedagogical tool for practicing death notification-experiences from Swedish medical students2011In: BMC Medical Education, ISSN 1472-6920, E-ISSN 1472-6920, Vol. 11, no 74, p. 7-Article in journal (Refereed)
    Abstract [en]

    Background: One of the toughest tasks in any profession is the deliverance of death notification. Marathon Death is an exercise conducted during the fourth year of medical school in northern Sweden to prepare students for this responsibility. The exercise is designed to enable students to gain insight into the emotional and formal procedure of delivering death notifications. The exercise is inspired by Augusto Boal's work around Forum Theatre and is analyzed using video playback. The aim of the study was to explore reflections, attitudes and ideas toward training in delivering death notifications among medical students who participate in the Marathon Death exercise based on forum play.

    Methods: After participation in the Marathon Death exercise, students completed semi-structured interviews. The transcribed interviews were analyzed using the principles of qualitative content analysis including a deductive content analysis approach with a structured matrix based on Bloom's taxonomy domains.

    Results: The Marathon Death exercise was perceived as emotionally loaded, realistic and valuable for the future professional role as a physician. The deliverance of a death notification to the next of kin that a loved one has died was perceived as difficult. The exercise conjured emotions such as positive expectations and sheer anxiety. Students perceived participation in the exercise as an important learning experience, discovering that they had the capacity to manage such a difficult situation. The feedback from the video playback of the exercise and the feedback from fellow students and teachers enhanced the learning experience.

    Conclusions: The exercise, Marathon Death, based on forum play with video playback is a useful pedagogical tool that enables students to practice delivering death notification. The ability to practice under realistic conditions contributes to reinforce students in preparation for their future professional role.

  • 283.
    Nordström, Anna
    et al.
    Umeå University, Faculty of Medicine, Department of Community Medicine and Rehabilitation, Geriatric Medicine. Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Sports Medicine.
    Fjellman-Wiklund, Anncristine
    Umeå University, Faculty of Medicine, Department of Community Medicine and Rehabilitation, Physiotherapy.
    Grysell, Tomas
    The effect of a role-playing exercise on clerkshipstudents’ views of death notification: the Swedish experience2011In: International Journal of Medical Education, ISSN 2042-6372, Vol. 2, p. 24-29Article in journal (Refereed)
    Abstract [en]

    Objectives The purpose of this study was to examine clerkship students' perspective towards delivering death notifications. An additional purpose of the study was to identify the learning needs of students following a role play exercise in delivering death notifications.

    Methods Participants in this study were fourth-year medical students (N=86) ranging in age from 22-43 years with a mean age of 27.1 years. There were 28 women and 58 men. Questionnaires, consisting of open-ended questions and a visual analogue scale (VAS), were administered before and after the "Marathon Death" role play exercise.

    Results Six categories emerged from the analysis of the questionnaire: communication, emotions, self-development, exercise-related, learning opportunities and tools and strategies. Results from the visual analogue scale showed that the majority of students (60%) needed to practice how to deliver difficult messages in death notifications. After taking part in the role-playing activity with video playback, where the students had an opportunity to view, discuss and reenact scenarios, seventy-six out of 78 (97.4%) stated that they had received training in communication skills. The responding students rated the exercise as highly relevant, scoring it a mean of 91 on a VAS scale of 0 to 100 mm.

    Conclusions Students are not competent in the communication skills required for delivering death notifications. A majority of students expressed a need for training in communication skills. The "Marathon Death" role play exercise provides initial training and emotional support for delivering a death notification. However, further empirical studies are required about the effect of the exercise on delivering the notification of death.

  • 284.
    Nordström, Anna
    et al.
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Sports Medicine.
    Gerdhem, Paul
    Department of Orthopaedics, Malmö University Hospital, Sweden.
    Brändström, Helena
    Department of Medical Sciences, Uppsala University, Sweden .
    Stiger, Fredrik
    Department of Medical Sciences, Uppsala University, Sweden .
    Lerner, Ulf
    Umeå University, Faculty of Medicine, Department of Odontology, Oral Cell Biology.
    Lorentzon, Mattias
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Sports Medicine.
    Obrant, Karl
    Department of Orthopaedics, Malmö University Hospital, Sweden.
    Nordström, Peter
    Umeå University, Faculty of Medicine, Department of Community Medicine and Rehabilitation, Geriatric Medicine. Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Sports Medicine.
    Åkesson, Kristina
    Department of Orthopaedics, Malmö University Hospital, Sweden.
    Interleukin-6 promoter polymorphism is associated with bone quality assessed by calcaneus ultrasound and previous fractures in a cohort of 75-year-old women2004In: Osteoporosis International, ISSN 0937-941X, E-ISSN 1433-2965, ISSN 0937-941X, Vol. 15, no 10, p. 820-826Article in journal (Refereed)
    Abstract [en]

    Interleukin 6 (IL-6) is a multifunctional cytokine and a potent stimulator of bone resorption and has been implicated in the pathogenesis of osteoporosis in postmenopausal women. The aim of this study was to investigate if a functional IL-6 promoter polymorphism (-174) was related to bone mass and fractures in a cohort consisting of 964 postmenopausal Caucasian women aged 75 years. Bone mineral density (BMD; g/cm2) of the femoral neck, lumbar spine and total body was measured using dual energy X-ray absorptiometry (DXA). Quantitative ultrasound (QUS) was also measured in the calcaneus and quantified as speed of sound (SOS; m/s), broadband ultrasound attenuation (BUA; dB/MHz), and stiffness index (SI). IL-6 genotypes was determined by restriction fragment length polymorphism (RFLP) using the restriction enzyme NlaIII. The frequencies of the different IL-6 genotypes were 27.5% (GG), 47.9% (GC), 24.6% (CC). The IL-6 polymorphism (presence of G) was independently related to a lower stiffness (beta=-0.07; P=0.03) and BUA (beta=-0.08; P=0.02), but not to BMD at any site measured by DXA. In the cohort, 420 subjects (44%) reported at least one fracture during their lifetime, and 349 (36%) reported at least one fracture after the age of 50. Using binary logistic regression, the IL-6 polymorphism (presence of G) was significantly related to an increased risk of a previous fracture during life (odds ratio 1.46, 95% CI 1.08-1.97) and to an increased risk of a fracture occurring after 50 years of age (odds ratio 1.37, 95% CI 1.004-1.88). The risk was further increased for fractures grouped as osteoporotic fractures (odds ratio 1.67, 95% CI 1.14-2.45), including forearm fractures (odds ratio 1.59, 95% CI 1.05-2.40). In conclusion, presence of G allele in the IL-6 promoter polymorphism at position -174 is independently related to previous fractures in postmenopausal women. This association may be related primarily to an altered bone quality identified by QUS and not a lower bone mass. This is also the first demonstration of association of IL-6 gene polymorphism to calcaneal QUS.

  • 285.
    Nordström, Anna
    et al.
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Sports Medicine. Umeå University, Faculty of Medicine, Department of Community Medicine and Rehabilitation, Rehabilitation Medicine.
    Högström, Gabriel
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Sports Medicine.
    Eriksson, Anders
    Department of Health Sciences, Luleå University of Technology, Luleå.
    Bonnerud, Patrik
    Department of Health Sciences, Luleå University of Technology, Luleå.
    Tegner, Yelverton
    Department of Health Sciences, Luleå University of Technology, Luleå.
    Malm, Christer
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Sports Medicine. Winternet, Boden, Idrottsmedicin.
    Higher muscle mass but lower gynoid fat mass in athletes using anabolic androgenic steroids2012In: Journal of Strength and Conditioning Research, ISSN 1064-8011, E-ISSN 1533-4287, Vol. 26, no 1, p. 246-250Article in journal (Refereed)
    Abstract [en]

    Nordstrom, A, Hogstrom, G, Eriksson, A, Bonnerud, P, Tegner, Y, and Malm, C. Higher muscle mass but lower gynoid fat mass in athletes using anabolic androgenic steroids. J Strength Cond Res 26(1): 246-250, 2012-This study evaluated the relationship between anabolic androgenic steroid (AAS) use and body constitution. Dual-energy x-ray absorptiometry was used to measure bone mineral density (BMD, g.cm(-2)) of the total body, arms, and legs. Total gynoid and android fat mass (grams) and total lean mass (grams) were measured in 10 strength trained athletes (41.4 +/- 7.9 years) who had used AASs for 5-15 years (Doped) and 7 strength trained athletes (29.4 +/- 6.2 years) who had never used AASs (Clean). Seventeen sedentary men (30.3 +/- 2.1 years) served as Controls. Doped athletes had significantly more lean body mass (85.5 +/- 3.8 vs. 75.3 +/- 2.5 vs. 60.7 +/- 1.9, p < 0.001) and a greater index of fat-free/fat mass (5.8 vs. 2.6 vs. 2.5, p < 0.001) compared with Clean athletes and Controls. Doped athletes also had significantly less gynoid fat mass compared with that of Clean athletes (2.8 +/- 0.4 vs. 4.8 +/- 0.2 kg, p = 0.02). There were no differences in BMD between the athletes (p = 0.39-0.98), but both groups had significantly higher BMDs at all sites compared with that of Controls (p = 0.01 to <0.001). Thus, long-term AAS use seems to alter body constitution, favoring higher muscle mass and reduced gynoid fat mass without affecting BMD.

  • 286.
    Nordström, Anna
    et al.
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Sports Medicine. Idrottsmedicin.
    Högström, Magnus
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Sports Medicine. Idrottsmedicin.
    Nordström, Peter
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Sports Medicine. Umeå University, Faculty of Medicine, Department of Community Medicine and Rehabilitation, Geriatric Medicine.
    Effects of different types of weight-bearing loading on bone mass and size in young males: A longitudinal study.2007In: Bone, ISSN 8756-3282, E-ISSN 1873-2763, Vol. 42, no 3, p. 565-571Article in journal (Refereed)
  • 287.
    Nordström, Anna
    et al.
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Sports Medicine. Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Medicine.
    Karlsson, Caroline
    Nyquist, Fredrik
    Olsson, Tommy
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Medicine.
    Nordström, Peter
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Sports Medicine. Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Medicine.
    Karlsson, Magnus
    Bone loss and fracture risk after reduced physical activity.2005In: Journal of Bone and Mineral Research, ISSN 0884-0431, E-ISSN 1523-4681, Vol. 20, no 2, p. 202-207Article in journal (Refereed)
    Abstract [en]

    Former male young athletes partially lost benefits in BMD (g/cm2) with cessation of exercise, but, despite this, had a higher BMD 4 years after cessation of career than a control group. A higher BMD might contribute to the lower incidence of fragility fractures found in former older athletes > or =60 years of age compared with a control group. INTRODUCTION: Physical activity increases peak bone mass and may prevent osteoporosis if a residual high BMD is retained into old age. MATERIALS AND METHODS: BMD was measured by DXA in 97 male young athletes 21.0 +/- 4.5 years of age (SD) and 48 controls 22.4 +/- 6.3 years of age, with measurements repeated 5 years later, when 55 of the athletes had retired from sports. In a second, older cohort, fracture incidence was recorded in 400 former older athletes and 800 controls > or =60 years of age. RESULTS: At baseline, the young athletes had higher BMD than controls in total body (mean difference, 0.08 g/cm2), spine (mean difference, 0.10 g/cm2), femoral neck (mean difference, 0.13 g/cm2), and arms (mean difference, 0.05 g/cm2; all p < 0.001). During the follow-up period, the young athletes who retired lost more BMD than the still active athletes at the femoral neck (mean difference, 0.07 g/cm2; p = 0.001) and gained less BMD at the total body (mean difference, 0.03 g/cm2; p = 0.004). Nevertheless, BMD was still higher in the retired young athletes (mean difference, 0.06-0.08 g/cm2) than in the controls in the total body, femoral neck, and arms (all p < 0.05). In the older cohort, there were fewer former athletes > or =60 of age than controls with fragility fractures (2.0% versus 4.2%; p < 0.05) and distal radius fractures (0.75% versus 2.5%; p < 0.05). CONCLUSIONS: Although exercise-induced BMD benefits are reduced after retirement from sports, former male older athletes have fewer fractures than matched controls.

  • 288.
    Nordström, Anna
    et al.
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Sports Medicine. Umeå University, Faculty of Medicine, Department of Community Medicine and Rehabilitation, Rehabilitation Medicine.
    Neovius, Martin G
    Rössner, Stephan
    Nordström, Peter
    Umeå University, Faculty of Medicine, Department of Community Medicine and Rehabilitation, Geriatric Medicine. Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Sports Medicine.
    Postpubertal development of total and abdominal percentage body fat: an 8-year longitudinal study.2008In: Obesity, ISSN 1930-7381, Vol. 16, no 10, p. 2342-2347Article in journal (Refereed)
    Abstract [en]

    The aim of the present study was to describe postpubertal changes in total and abdominal adiposity in young men and the relation to changes in physical activity (PA). The study included 107 white men with a mean age of 17.1 +/- 1.7 years at baseline. Total percentage body fat (%BF) and abdominal percentage body fat (abd%BF) were measured at baseline and after a mean time of 28, 68, and 92 months using dual-energy X-ray absorptiometry (DXA). PA (h/week) was assessed at each visit by questionnaire. Over the study period, significant increases of 7.8 +/- 5.5%BF and 9.0 +/- 5.6 abd%BF were observed. Subjects who were active athletes throughout the study (n = 24), or nonathletes not changing their level of PA during follow-up (n = 27) increased 5.7 +/- 3.2 and 8.1 +/- 6.7%BF, respectively. Athletes who quit organized training during follow-up period (n = 56) increased by 8.7 +/- 4.9%BF. In the total cohort, the average annual gains in BMI, %BF, and abd%BF were 0.4 kg/m(2), 0.9%BF, and 1.1abd%BF (all P < 0.0001), respectively. Adjustment for changes in PA altered the coefficient magnitudes only marginally. Changes in PA were, however, significantly and inversely associated with changes in %BF and abd%BF (P = 0.005 and P = 0.02, respectively), but were not significantly associated with BMI development (P = 0.15). In summary, our results indicate that the natural course of adiposity development in postpubertal men is characterized by adiposity gains. The influence of PA on especially abd%BF may influence the future risk of cardiovascular disease.

  • 289.
    Nordström, Anna
    et al.
    Umeå University, Faculty of Medicine, Department of Community Medicine and Rehabilitation. Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Sports Medicine.
    Nordström, Peter
    Umeå University, Faculty of Medicine, Department of Community Medicine and Rehabilitation, Geriatric Medicine.
    Cognitive Performance in Late Adolescence and the Subsequent Risk of Subdural Hematoma: An Observational Study of a Prospective Nationwide Cohort2011In: PLoS Medicine, ISSN 1549-1277, E-ISSN 1549-1676, Vol. 8, no 12, p. e1001151-Article in journal (Refereed)
    Abstract [en]

    Background: There are few identified risk factors for traumatic brain injuries such as subdural hematoma (SDH). The aim of the present study was to investigate whether low cognitive performance in young adulthood is associated with SDH later in life. A second aim was to investigate whether this risk factor was associated with education and physical fitness. Methods and Findings: Word recollection, logical, visuospatial, and technical performances were tested at a mean age of 18.5 years in a prospective nation-wide cohort of 440,742 men. An estimate of global intelligence was calculated from these four tests. Associations between cognitive performance, education, physical fitness, and SDH during follow-up were explored using Cox regression analyses. During a median follow-up of 35 years, 863 SDHs were diagnosed in the cohort. Low global intelligence was associated with an increased risk of SDH during follow-up (hazard ratio [HR]: 1.33, per standard deviation decrease, 95% CI = 1.25-1.43). Similar results were obtained for the other measures of cognitive performance (HR: 1.24-1.33, p<0.001 for all). In contrast, a high education (HR: 0.27, comparing more than 2 years of high school and 8 years of elementary school, 95% CI = 0.19-0.39), and a high level of physical fitness (HR: 0.76, per standard deviation increase, 95% CI = 0.70-0.83), was associated with a decreased risk of suffering from a SDH. Conclusions: The present findings suggest that reduced cognitive function in young adulthood is strongly associated with an increased risk of SDH later in life. In contrast, a higher level of education and a higher physical fitness were associated with a decreased risk of SDH.

  • 290.
    Nordström, Anna
    et al.
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Sports Medicine.
    Nordström, Peter
    Umeå University, Faculty of Medicine, Department of Community Medicine and Rehabilitation, Geriatric Medicine.
    Ett bensäkert råd för framtiden2011In: Svensk Idrottsforskning: Organ för Centrum för Idrottsforskning, ISSN 1103-4629, no 2, p. 58-60Article in journal (Other academic)
  • 291.
    Nordström, Anna
    et al.
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Sports Medicine.
    Nordström, Peter
    Umeå University, Faculty of Medicine, Department of Community Medicine and Rehabilitation, Geriatric Medicine.
    Prevention of bone loss with exercise2012In: Diet, nutrients and bone health, CRC Press, 2012, p. 493-508Chapter in book (Refereed)
  • 292.
    Nordström, Anna
    et al.
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Sports Medicine.
    Nordström, Peter
    Umeå University, Faculty of Medicine, Department of Community Medicine and Rehabilitation, Geriatric Medicine.
    The effect of detraining on bone2011In: Open Bone Journal, ISSN 1876-5254, no 3, p. 22-30Article in journal (Refereed)
    Abstract [en]

    Physical activity has been recommended for the treatment and even prevention of osteoporosis. This is because physical activity can potentially increase bone mass and strength in the early years of life and reduce the risk of falling in older populations. However, a key question that remains to be answered is whether a high bone mineral density (BMD) resulting from physical activity is sustained despite decreased activity. The aim of this review is to describe the effects of decreased levels of physical activity on bone.A comprehensive search of Medline, EMBASE, and the Cochrane controlled trials register was conducted. Previous studies have reported that benefits from prior physical activity seem to be eroded after cessation of this activity, at least for bone sites that are rich in trabecular bone such as the clinically important proximal femur. In bone sites rich in cortical bone, there appeared to be long-term beneficial effects of physical activity.In conclusion, bone gain through physical activity is lost in bone sites rich in trabecular bone if the activity is not maintained. However, current knowledge is limited and further prospective research into the effect of detraining is recommended.

  • 293.
    Nordström, Anna
    et al.
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Sports Medicine. Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Occupational and Environmental Medicine.
    Nordström, Peter
    Umeå University, Faculty of Medicine, Department of Community Medicine and Rehabilitation, Geriatric Medicine.
    Ekstrand, Jan
    Football Research Group, Division of Community Medicine, Department of Medical and Health Sciences, Linköping University, Linköping, Sweden.
    Sports-related concussion increases the risk of subsequent injury by about 50% in elite male football players2014In: British Journal of Sports Medicine, ISSN 0306-3674, E-ISSN 1473-0480, Vol. 48, no 19, p. 1447-1450Article in journal (Refereed)
    Abstract [en]

    Background Little is known about the short-term and long-term sequelae of concussion, and about when athletes who have sustained such injuries can safely return to play. Purpose To examine whether sports-related concussion increases the risk of subsequent injury in elite male football players. Study design Prospective cohort study. Methods Injuries were registered for 46 male elite football teams in 10 European countries in the 2001/ 2002-2011/ 2102 seasons. Two survival models were used to analyse whether concussion increased the subsequent risk of an injury in the first year. Results During the follow-up period, 66 players sustained concussions and 1599 players sustained other injuries. Compared with the risk following other injuries, concussion was associated with a progressively increased risk of a subsequent injury in the first year (0 to <3 months, HR=1.56, 95% CI 1.09 to 2.23; 3 to <6 months, HR=2.78, 95% CI 1.58 to 4.89; 6-12 months, HR=4.07, 95% CI 2.14 to 7.76). In the second model, after adjustment for the number of injuries in the year preceding the concussion, this injury remained significantly associated with the risk of subsequent injury in the first year (HR=1.47, 95% CI 1.05 to 2.05). Conclusions Concussion was a risk factor for sustaining subsequent injury within the following year. In-depth medical evaluation, which includes neurological and cognitive assessment, is warranted within the concussion management and return-to-play process.

  • 294.
    Nordström, Anna
    et al.
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Medicine. Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Sports Medicine.
    Olsson, Tommy
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Medicine.
    Nordström, Peter
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Sports Medicine. Umeå University, Faculty of Medicine, Department of Community Medicine and Rehabilitation, Geriatric Medicine.
    Bone gained from physical activity and lost through detraining: a longitudinal study in young males.2005In: Osteoporosis International, ISSN 0937-941X, E-ISSN 1433-2965, Vol. 16, no 7, p. 835-841Article in journal (Refereed)
    Abstract [en]

    The aim of this study was to investigate the effect of training and detraining on bone mineral density of both weight-bearing and non-weight-bearing bone in a cohort of young males who participated in ice hockey training. Forty-three healthy adolescent ice hockey players (16.7+/-0.6 years) training for a mean of 9.7+/-2.4 h/week and 25 control subjects (16.8+/-0.3 years) training for 2.1+/-2.7 h/week, were included in this longitudinal study. Bone mineral density (BMD, g/cm2) of the arms, the dominant and non-dominant humerus, dominant and non-dominant femur, and the right femoral neck, total hip, and bone area of the femur, humerus and hip were measured at baseline and again after 30 and 70 months using dual-energy X-ray absorptiometry. From baseline to the first follow-up, athletes gained significantly more BMD in the femoral neck (0.07 versus 0.03 g/cm2) and arms (0.09 versus 0.06 g/cm2) compared with the controls (P = 0.04 for both). Between the first and the second follow-up, 21 ice hockey players stopped their active sports career. These men lost significantly more BMD at the femoral neck (-0.02 versus -0.10 g/cm2, P < 0.001), total hip (-0.05 versus -0.09, P = 0.04), dominant (0.02 versus -0.03 g/cm2, P = 0.009) and non-dominant humerus (0.03 versus -0.01 g/cm2, P = 0.03) than the still active ice hockey players (n = 22). At the second follow-up examination, at 22 years of age, the former ice hockey players still had significantly higher BMD at the non-dominant humerus than the controls (P < 0.01). During the total study period, the still active athletes (n = 22) gained significantly more BMD compared with the controls at the femoral neck (0.09 g/cm2; P = 0.008), total hip (0.05 g/cm2, P = 0.04) and arms (0.07 g/cm2; P = 0.01). No differences were seen in bone areas when comparing the different groups. In conclusion, training associated with ice hockey is related to continuous accumulation of BMD after puberty in males. Reduced activity is followed by BMD loss within 3 years of cessation of sports career at predominantly weight-bearing sites. The effects are confined to bone density and not bone size.

  • 295.
    Nordström, Anna
    et al.
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Sports Medicine.
    Olsson, Tommy
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Medicine.
    Nordström, Peter
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Sports Medicine. Umeå University, Faculty of Medicine, Department of Community Medicine and Rehabilitation, Geriatric Medicine.
    Sustained benefits from previous physical activity on bone mineral density in males.2006In: Journal of Clinical Endocrinology and Metabolism, ISSN 0021-972X, E-ISSN 1945-7197, Vol. 91, no 7, p. 2600-2604Article in journal (Refereed)
    Abstract [en]

    Context: The effect of physical activity on bone mineral density (BMD) is not well investigated longitudinally after puberty in men.

    Objective: Our objective was to evaluate the effect of exercise and reduced exercise on BMD after puberty in men.

    Design: We conducted a longitudinal study.

    Participants: Sixty-three healthy young athletes and 27 male controls, both with a mean age of 17 yr at baseline, participated. Also, 136 of the participants’ parents were investigated to evaluate heritable influences.

    Main Outcome Measures: Total body, total hip, femoral neck, and humerus BMD (grams per square centimeter) were measured at baseline and after mean periods of 27, 68, and 94 months in the young cohort.

    Results: BMDs of control parents and athlete parents were equal, suggesting absence of selection bias. The 23 athletes that remained active throughout the study increased BMD at all sites when compared with controls (mean difference, 0.04–0.12 g/cm2; P < 0.05) during the study period. After an average of 3 yr, 27 athletes ended their active careers. Although this group initially lost BMD at the hip compared with active athletes, the former athletes still had higher BMD than controls at the femoral neck (0.12 g/cm2; P = 0.007), total hip (0.11 g/cm2; P = 0.02), and humerus (0.10 g/cm2; P = 0.02) at the final follow-up.

    Conclusions: High sensitivity to physical loading persists after puberty in men. Reduced physical activity is associated with BMD loss in the first 3 yr in weight-bearing bone. Sustained benefits in BMD are preserved 5 yr after intensive training ends.

  • 296.
    Nordström, Anna
    et al.
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Sports Medicine.
    Tervo, Taru
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Sports Medicine.
    Högström, Magnus
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Sports Medicine.
    The effect of physical activity on bone accrual, osteoporosis and fracture prevention2011In: Open Bone Journal, ISSN 1876-5254, no 3, p. 11-21Article in journal (Refereed)
    Abstract [en]

    Background: Physical activity has been recommended for the prevention and even treatment of osteoporosis because it potentially can increase bone mass and strength during childhood and adolescence and reduce the risk of falling in older populations. However, few reports have systematically investigated the effect of physical activity on bone in men and women of different ages.

    Purpose: The goal of this study was to review the literature relating to the effect of physical activity on bone mineral density in men and women of various ages.

    Method: This review systematically evaluates the evidence for the effect of physical activity on bone mineral density. Cochrane and Medline databases were searched for relevant articles, and the selected articles were evaluated.

    Results: The review found evidence to support the effectiveness of weight bearing physical activity on bone accrual during childhood and adolescence. The effect of weight bearing physical activity was site-specific. In contrast, the role of physical activity in adulthood is primarily geared toward maintaining bone mineral density. The evidence for a protective effect of physical activity on bone is not as solid as that for younger individuals.

    Conclusions: The effect of weight bearing physical activity is seen in sites that are exposed to loading. There also seems to be a continuous adaptive response in bone to loading. Additional randomized, controlled studies are needed to evaluate the effect of physical activity in the elderly.

  • 297.
    Nordström, Anna
    et al.
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Medicine. Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Sports Medicine.
    Thorsen, Kim
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Sports Medicine.
    Nordström, Peter
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Sports Medicine. Umeå University, Faculty of Medicine, Department of Community Medicine and Rehabilitation, Geriatric Medicine.
    A 3-year longitudinal study of the effect of physical activity on the accrual of bone mineral density in healthy adolescent males.2003In: Calcified Tissue International, ISSN 0171-967X, E-ISSN 1432-0827, Vol. 73, no 2, p. 108-114Article in journal (Refereed)
    Abstract [en]

    It has previously been suggested that physical activity predominantly influences the accumulation of bone density before puberty. The purpose of the present study was to examine the effect of physical activity on the accumulation of bone mass in male athletes between 16 and 19 years of age. The cohort studied consisted of 12 badminton players (aged 16.1 +/- 0.5), 20 ice hockey players (aged 16.1 +/- 0.5), and 24 age-matched controls (aged 16.1 +/- 0.6). The bone mineral density (BMD, g/cm2) of the total body, spine, dominant and nondominant humerus, head and femoral neck was measured twice with a 3-year interval by dual energy X-ray absorptiometry (DXA). In addition, at the femoral neck, volumetric bone mineral density (vBMD, mg/cm3) was estimated. At baseline, the athletes as a whole group had significantly higher BMD at the total body (P = 0.03), dominant (P = 0.006) and nondominant humerus (P = 0.009) and femoral neck (P = 0.007) compared to the controls. At the 3-year followup, the athletes had significantly higher BMD at all sites (total body; P = 0.003, spine; P = 0.02, dominant humerus; P = 0.001, nondominant humerus; P = < 0.001, femoral neck; P = 0.001) except for the head (P = 0.91) compared with controls. The athletes also had higher vBMD at the femoral neck compared with the controls (P = 0.01). Furthermore, to be an athlete was found to be independently associated with a higher increase in nondominant humerus BMD (beta = 0.24; P < 0.05) and femoral neck BMD (beta = 0.30; P < 0.05) compared with the controls, during the study period. In summary, these results suggests that it is possible to achieve continuous gains in bone mass in sites exposed to osteogenic stimulation after puberty in males by engaging in weight-bearing physical activity.

  • 298.
    Nordström, Peter
    et al.
    Umeå University, Faculty of Medicine, Department of Community Medicine and Rehabilitation, Geriatric Medicine.
    Eklund, Fredrik
    Umeå University, Faculty of Medicine, Department of Community Medicine and Rehabilitation, Geriatric Medicine.
    Björnstig, Ulf
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Surgery.
    Nordström, Anna
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Sports Medicine.
    Lorentzon, Ronny
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Sports Medicine.
    Sievänen, Harri
    Gustafson, Yngve
    Umeå University, Faculty of Medicine, Department of Community Medicine and Rehabilitation, Geriatric Medicine.
    Do both areal BMD and injurious falls explain the higher incidence of fractures in women than in men?2011In: Calcified Tissue International, ISSN 0171-967X, E-ISSN 1432-0827, Vol. 89, no 3, p. 203-210Article in journal (Refereed)
    Abstract [en]

    The higher incidence of fractures in women than in men is generally attributed to the lower areal bone mineral density (areal BMD, g/cm(2)) of the former. The purpose of the present study was to investigate both areal BMD and injurious falls as risk factors for fractures. In a first cohort, areal BMD was measured in 5,131 men and women (age range 40-95 years). In a second cohort, consisting of 26,565 men and women (age range 40-69 years), a health survey was conducted including questions about lifestyle and medication. Main outcome measures included validated prospective injurious falls and fractures in both cohorts. The higher areal BMD and femoral neck BMD in men compared to women (P < 0.001) were explained by a higher diameter of the femoral neck. Importantly, the diameter of the femoral neck was not associated with fractures in either sex (hazard ratio [HR] 0.94-1.04, P > 0.05 for all), suggesting that a higher areal BMD and lower incidence of osteoporosis in men do not explain their lower incidence of fractures. In contrast, women were more prone to sustain injurious falls than men in both cohorts investigated (HR for women = 1.61 and 1.84, P < 0.001 for both), resulting in a higher incidence of fractures (HR for women = 2.24 and 2.36, P < 0.001 for both). The number of injurious falls and fractures occurring each month during the study period showed a very strong correlation in both women (r = 0.95, P < 0.00001) and men (r = 0.97, P < 0.00001). In summary, low areal BMD, and thus osteoporosis, may not explain the higher fracture incidence in women than in men. Instead, a higher incidence of injurious falls in women was strongly associated with the higher fracture risk.

  • 299.
    Nordström, Peter
    et al.
    Umeå University, Faculty of Medicine, Department of Community Medicine and Rehabilitation, Geriatric Medicine. Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Sports Medicine.
    Franks, Paul
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Medicine.
    Gustafson, Yngve
    Umeå University, Faculty of Medicine, Department of Community Medicine and Rehabilitation, Geriatric Medicine.
    Nordström, Anna
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Sports Medicine.
    Cognitive function in young men and the later risk of fractures2012In: Journal of Bone and Mineral Research, ISSN 0884-0431, E-ISSN 1523-4681, Vol. 27, no 11, p. 2291-2297Article in journal (Refereed)
    Abstract [en]

    Dementia has been associated with an increased risk of fractures. These associations may be explained by an impaired cognitive function, as well as comorbid illness and toxic reaction from drugs. To investigate whether cognitive function in young, healthy individuals already affects the risk of fractures, overall cognitive function scores were calculated from four cognitive tests accomplished during a national conscriptions test in 960,956 men with a mean age of 18 years. Incident fractures were searched in national registers. During a median follow-up of 30 years (range 0 to 41 years), 65,313 men had one fracture and 2589 men had a hip fracture. Compared with men with no fracture, overall cognitive function at baseline was 3.5% lower for men sustaining one fracture and 5.5% lower for men sustaining a hip fracture (p < 0.001 for both). When comparing the lowest and the highest decile, low overall cognitive function scores increased the risk one fracture (hazard ratio [HR] = 1.55, 95% confidence interval [CI] 1.50-1.61) and a hip fracture (HR = 2.12, 95% CI 1.77-2.55), after adjustment for confounders. A higher education (university level versus elementary school) was associated with a decreased risk of a fracture (HR = 0.67, 95% CI 0.65-0.69) and a hip fracture (HR = 0.51, 95% CI 0.45-0.57). The effects of education and cognitive function were reduced when also adjusting for total income and disability pension. In summary, low cognitive function and education in young men were associated with the later risk of especially hip fractures. These associations may partly be mediated by socioeconomic factors. © 2012 American Society for Bone and Mineral Research.

  • 300.
    Nordström, Peter
    et al.
    Umeå University, Faculty of Medicine, Department of Community Medicine and Rehabilitation, Geriatric Medicine.
    Michaelsson, Karl
    Gustafson, Yngve
    Umeå University, Faculty of Medicine, Department of Community Medicine and Rehabilitation, Geriatric Medicine.
    Nordström, Anna
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Sports Medicine. Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Occupational and Environmental Medicine.
    Traumatic brain injury and young onset dementia: a nationwide cohort study2014In: Annals of Neurology, ISSN 0364-5134, E-ISSN 1531-8249, Vol. 75, no 3, p. 374-381Article in journal (Refereed)
    Abstract [en]

    Objective To investigate the association between traumatic brain injuries (TBIs) and the risk of young onset dementia (YOD), that is, dementia before 65 years of age. Methods The study cohort comprised 811,622 Swedish men (mean age = 18 years) conscripted for military service between 1969 and 1986. TBIs, dementia, and covariates were extracted from national registers. Time-dependent exposures using Cox proportional hazard regression models were evaluated. Results During a median follow-up period of 33 years, there were 45,249 men with at least 1 TBI in the cohort. After adjustment for covariates, 1 mild TBI (hazard ratio [HR] = 1.0, 95% confidence interval [CI] = 0.5-2.0), at least 2 mild TBIs (HR = 2.5, 95% CI = 0.8-8.1), or 1 severe TBI (HR = 0.7, 95% CI = 0.1-5.2) were not associated with Alzheimer dementia (AD). Other types of dementia were strongly associated with the risk of 1 mild TBI (HR = 3.8, 95% CI = 2.8-5.2), at least 2 mild TBIs (HR = 10.4, 95% CI = 6.3-17.2), and 1 severe TBI (HR = 11.4, 95% CI = 7.4-17.5) in age-adjusted analysis. However, these associations were largely attenuated after adjustment for covariates (1 mild TBI: HR = 1.7; at least 2 mild TBIs: HR = 1.7; 1 severe TBI: HR = 2.6; p < 0.05 for all). Interpretation In the present study, we found strong associations between YOD of non-AD forms and TBIs of different severity. These associations were, however, markedly attenuated after multivariate adjustment.

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