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  • 101.
    Carlsson, Lena
    et al.
    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.
    Thornell, Lars-Eric
    Umeå University, Faculty of Medicine, Department of Integrative Medical Biology (IMB), Anatomy.
    New aspects of obscurin in human striated muscles.2008In: Histochemistry and Cell Biology, ISSN 0948-6143, E-ISSN 1432-119X, Vol. 130, no 1, p. 91-103Article in journal (Refereed)
    Abstract [en]

    Obscurin is a giant protein (700-800 kDa) present in both skeletal muscles and myocardium. According to animal studies, obscurin interacts with myofibrillar Z-discs during early muscle development, but is translocalised to be predominantly associated with the M-bands in mature muscles. The proposed function for obscurin is in the assembly and organisation of myosin into regular A-bands during formation of new sarcomeres. In the present study, the precise localisation of obscurin in developing and mature normal human striated muscle is presented for the first time. We show that obscurin surrounded myofibrils at the M-band level in both developing and mature human skeletal and heart muscles, which is partly at variance with that observed in animals. At maturity, obscurin also formed links between the peripheral myofibrils and the sarcolemma, and was a distinct component of the neuromuscular junctions. Obscurin should therefore be regarded as an additional component of the extrasarcomeric cytoskeleton. To test this function of obscurin, biopsies from subjects with exercise-induced delayed onset muscle soreness (DOMS) were examined. In these subjects, myofibrillar alterations related to sarcomerogenesis are observed. Our immunohistochemical analysis revealed that obscurin was never lacking in myofibrillar alterations, but was either preserved at the M-band level or diffusely spread over the sarcomeres. As myosin was absent in such areas but later reincorporated in the newly formed sarcomeres, our results support that obscurin also might play an important role in the formation and maintenance of A-bands.

  • 102.
    Carlsson, Magnus
    et al.
    Department of Health and Social Sciences, Dalarna University, Falun, Sweden. Dala Sports Academy, Falun, Sweden..
    Carlsson, Tomas
    Department of Health and Social Sciences, Dalarna University, Falun, Sweden. Dala Sports Academy, Falun, Sweden..
    Hammarström, Daniel
    Department of Health and Social Sciences, Dalarna University, Falun, Sweden. Lillehammer University College, Lillehammer, Norway..
    Malm, Christer
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Sports Medicine.
    Tonkonogi, Michail
    Department of Health and Social Sciences, Dalarna University, Falun, Sweden. .
    Prediction of race performance of elite cross-country skiers by lean mass2014In: International Journal of Sports Physiology and Performance, ISSN 1555-0265, E-ISSN 1555-0273, Vol. 9, no 6, p. 1040-1045Article in journal (Refereed)
    Abstract [en]

    PURPOSE: To investigate the relationship between race performance and lean mass (LM) variables, as well as to examine sex differences in body composition in elite-standard cross-country skiers.

    METHODS: Thirty-four elite cross-country skiers (18 men and 16 women) underwent a dual-emission x-ray absorptiometry body composition test to determine LM, fat mass, and bone mineral content. For both sexes, performance data were collected from a sprint prologue and a distance race.

    RESULTS: The absolute expression of LM variables [whole body (LMWB), upper body (LMUB), and lower body (LMLB)] was significantly correlated with finishing time in the sprint prologue independent of sex. Distance-race performance was significantly related to LMWB, LMUB, and LMLB in women; however, no correlation was found in men. Men had a significantly higher LM and lower fat mass, independent of expression (absolute or relative), for the whole body, arms, trunk, and legs, except for the absolute fat mass in the trunk.

    CONCLUSIONS: The absolute expressions of LMWB, LMUB, and LMLB were significant predictors of sprint-prologue performance in both sexes, as well as of distance-race performance in women only. Compared with women, male skiers have a higher LM in the body segments that are major contributors to propelling forces. These results suggest that muscle mass in the lower and upper body is equally important for race performance; thus, more focus of elite skiers' training should be directed to increasing whole-body muscle mass to improve their competitive performance capability.

  • 103.
    Carlsson, Magnus
    et al.
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Sports Medicine. Department of Health and Social Sciences, Dalarna University, Falun, Sweden..
    Carlsson, Tomas
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Sports Medicine. Department of Health and Social Sciences, Dalarna University, Falun, Sweden..
    Hammarström, Daniel
    Department of Health and Social Sciences, Dalarna University, Falun, Sweden..
    Malm, Christer
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Sports Medicine.
    Tonkonogi, Michail
    Department of Health and Social Sciences, Dalarna University, Falun, Sweden..
    Time Trials Predict the Competitive Performance Capacity of Junior Cross-Country Skiers2014In: International Journal of Sports Physiology and Performance, ISSN 1555-0265, E-ISSN 1555-0273, Vol. 9, no 1, p. 12-18Article in journal (Refereed)
    Abstract [en]

    PURPOSE: This study investigated whether there is a correlation between time-trial performance and competitive performance capacity of male and female junior cross-country skiers and sought to explain gender-specific competitive performance capacity through multiple regression modeling.

    METHODS: The International Ski Federation's (FIS) junior ranking points for distance (FISdist) and sprint (FISsprint) competitions were used as performance parameters. A total of 38 elite junior (18.5 ± 1.0 years old) cross-country skiers (24 men and 14 women) completed three time-trial tests: a 3 km level running time trial (TTRun), a 2 km moderate uphill (1.2º slope) roller skiing time trial using the double poling technique (TTDP), and a 2 km uphill (2.8º slope) roller skiing time trial using the diagonal stride technique (TTDiag). The correlations were investigated using Pearson correlation analysis, and regression models were created using multiple linear regression analysis.

    RESULTS: For men, FISsprint and FISdist were correlated with the times for TTRun, TTDP, and TTDiag (all P < 0.001). For women, FISsprint was correlated with the times for TTRun (P < 0.05), TTDP (P < 0.01), and TTDiag (P < 0.01), whereas FISdist was correlated with the times for TTDP (P < 0.01) and TTDiag (P < 0.05). The models developed for FISdist and FISsprint explained 73.9-82.3% of the variance in the performance capacity of male junior cross-country skiers. No statistically valid regression model was found for the women.

    CONCLUSIONS: The running and roller skiing time trials are useful for the accurate prediction of the performance capacity of junior cross-country skiers.

  • 104.
    Carlsson, Magnus
    et al.
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Sports Medicine. Department of Health and Social Sciences, Dalarna University, Falun, Sweden..
    Carlsson, Tomas
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Sports Medicine. Department of Health and Social Sciences, Dalarna University, Falun, Sweden..
    Hammarström, Daniel
    Department of Health and Social Sciences, Dalarna University, Falun, Sweden..
    Tiivel, Toomas
    Department of Health and Social Sciences, Dalarna University, Falun, Sweden..
    Malm, Christer
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Sports Medicine. Winternet, Boden, Sweden..
    Tonkonogi, Michail
    Department of Health and Social Sciences, Dalarna University, Falun, Sweden..
    Validation of physiological tests in relation to competitive performances in elite male distance cross-country skiing2012In: Journal of Strength and Conditioning Research, ISSN 1064-8011, E-ISSN 1533-4287, Vol. 26, no 6, p. 1496-1504Article in journal (Refereed)
    Abstract [en]

    The purpose of the present study was to establish which physiological test parameters reflects the distance performances in the Swedish National Championships in cross-country skiing (SNC) and the International Ski Federation's ranking points for distance performances (FISdist). The present study also aimed to create multiple regression models to describe skiing performance for the SNC distance races and International Ski Federation's (FIS) ranking. Twelve male, Swedish, national elite, cross-country skiers (maximal oxygen consumption [V̇O2max] = 5.34 ± 0.34 L·min) volunteered to participate in the study. Their results in the 2008 SNC (15 km race [SNC15] and 30 km race [SNC30]) and FISdist points were used as performance data. On the week preceding the Championship, subjects completed a test battery consisting of 7 physiological tests: isokinetic knee extension peak torque (PT), vertical jumps (VJ), lactate threshold (LT), V̇O2max, and 3 double poling tests of different durations (DP20, DP60, and DP360). Correlations were established using Pearson's correlation analysis, and models to describe skiing performance were created using standard multiple linear regression analysis. Significant correlations were found between the performance parameters and test parameters derived from LT, V̇O2max, and DP60 tests. No correlations with any performance parameter were found for PT, VJ, DP20, and DP360 tests. For FISdist and SNC15, the models explain 81% and 78% of the variance in performance, respectively. No statistically valid regression model was found for SNC30. The results of this study imply that the physiological demands in male elite distance cross-country skiing performances are different in different events. To adequately evaluate a skier's performance ability in distance cross-country skiing, it is necessary to use test parameters and regression models that reflect the specific performance.

  • 105.
    Carlsson, Magnus
    et al.
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Sports Medicine. Department of Health and Social Sciences, Dalarna University, Falun, Sweden. Dala Sports Academy, Falun, Sweden..
    Carlsson, Tomas
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Sports Medicine. Department of Health and Social Sciences, Dalarna University, Falun, Sweden. Dala Sports Academy, Falun, Sweden..
    Knutsson, Magnus
    Department of Health and Social Sciences, Dalarna University, Falun, Sweden. Dala Sports Academy, Falun, Sweden..
    Malm, Christer
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Sports Medicine. Winternet, Boden, Sweden.
    Tonkonogi, Michail
    Department of Health and Social Sciences, Dalarna University, Falun, Sweden..
    Oxygen uptake at different intensities and sub-techniques predicts sprint performance in elite male cross-country skiers2014In: European Journal of Applied Physiology, ISSN 1439-6319, E-ISSN 1439-6327, Vol. 114, no 12, p. 2587-2595Article in journal (Refereed)
    Abstract [en]

    PURPOSE: To investigate the relationship between sprint-prologue performance (using the classical technique) and the oxygen uptake at the lactate threshold (V̇O2obla), maximal oxygen uptake (V̇O2max), and mean oxygen uptake during double poling (V̇O2dp).

    METHODS: Eight elite male cross-country skiers [age 24.8 ± 4.8 years, (mean ± SD)] completed two treadmill roller-skiing tests using the diagonal-stride technique and a 60 s double-poling test on a ski-ergometer to determine their V̇O2obla, V̇O2max, and V̇O2dp. Performance data were generated from a 1.25 km sprint prologue. Power-function modelling was used to predict the skiers' race speeds based on the oxygen-uptake variables and body mass.

    RESULTS: There were correlations between the race speed and the absolute expression of the V̇O2obla (r = 0.79, P = 0.021), V̇O2max (r = 0.86, P = 0.0069), and V̇O2dp (r = 0.94, P = 0.00062). The following power-function models were established for race-speed prediction: 1.09 · V̇O2obla(0.21), 1.05 · V̇O2max(0.21), and 1.19 · V̇O2dp(0.20); these models explained 60 % (P = 0.024), 73 % (P = 0.0073), and 87 % (P = 0.00073), respectively, of the variance in the race speed. However, body mass did not contribute to any of the models (P = 0.97, 0.88, and 0.21, respectively).

    CONCLUSIONS: Oxygen uptake at different intensities and sub-techniques is an indicator of elite male sprint-prologue performance. The absolute expression of the investigated oxygen-uptake variables should be used when evaluating elite male sprint-prologue performances; if skiers oxygen uptake differs by 1 %, their performances will likely differ by 0.2 % in favour of the skier with higher oxygen uptake.

  • 106.
    Carlsson, Magnus
    et al.
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Sports Medicine. School of Education, Health and Social Studies, Dalarna University, Falun, Sweden; Dala Sports Academy, Falun, Sweden.
    Carlsson, Tomas
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Sports Medicine. School of Education, Health and Social Studies, Dalarna University, Falun, Sweden; Dala Sports Academy, Falun, Sweden.
    Wedholm, Lars
    School of Education, Health and Social Studies, Dalarna University, Falun, Sweden; Dala Sports Academy, Falun, Sweden.
    Nilsson, Mattias
    Regional Sports Federation of Dalarna, Falun, Sweden.
    Malm, Christer
    Umeå University, Faculty of Medicine, Department of Community Medicine and Rehabilitation, Sports medicine.
    Tonkonogi, Michail
    School of Education, Health and Social Studies, Dalarna University, Falun, Sweden.
    Physiological demands of competitive sprint and distance performance in elite female cross-country skiing2016In: Journal of Strength and Conditioning Research, ISSN 1064-8011, E-ISSN 1533-4287, Vol. 30, no 8, p. 2138-2144Article in journal (Refereed)
    Abstract [en]

    The purpose was to investigate the relationship between elite females' competitive performance capability in sprint and distance cross-country skiing and the variables of gross efficiency (GE), work rate at the onset of blood-lactate accumulation (OBLA4mmol), maximal oxygen uptake (V[Combining Dot Above]O2max), maximal speed (Vmax), and peak upper-body oxygen uptake (V[Combining Dot Above]O2peak). Ten elite female cross-country skiers (age 24.5 ± 2.8 years) completed treadmill roller-skiing tests to determine GE, OBLA4mmol, and V[Combining Dot Above]O2max using the diagonal-stride technique as well as Vmax and V[Combining Dot Above]O2peak using the double-poling technique. International Ski Federations ranking points for sprint (FISsprint) and distance (FISdist) races were used as competitive performance data. There were correlations between the FISsprint and the V[Combining Dot Above]O2max expressed absolutely (p = 0.0040), Vmax (p = 0.012), and V[Combining Dot Above]O2peak expressed absolutely (p < 0.001) and as a simple ratio-standard (p = 0.049). The FISdist were correlated with OBLA4mmol (p = 0.048), V[Combining Dot Above]O2max expressed absolutely (L·min) (p = 0.015) and as a simple ratio-standard (p = 0.046), and V[Combining Dot Above]O2peak expressed absolutely (p = 0.036) and as a simple ratio-standard (ml·min·kg) (p = 0.040). The results demonstrate that the physiological abilities reflected by V[Combining Dot Above]O2max and V[Combining Dot Above]O2peak are indicators of competitive sprint and distance performance in elite female cross-country skiing. In addition, the ability to generate a high Vmax indicates the performance in sprint races, whereas the skier's OBLA4mmol reflects the performance capability in distance races. Based on the results, when evaluating the performance capacity of elite female cross-country skiers, it is recommended to use physiological variables that reflect competitive performance.

  • 107.
    Carlsson, Tomas
    et al.
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Sports Medicine. Department of Health and Social Sciences, Dalarna University, Falun, Sweden; Dala Sports Academy, Falun, Sweden..
    Carlsson, Magnus
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Sports Medicine. Department of Health and Social Sciences, Dalarna University, Falun, Sweden; Dala Sports Academy, Falun, Sweden..
    Felleki, Majbritt
    Department of Technology and Business Studies, Dalarna University, Borlänge, Sweden..
    Hammarström, Daniel
    Department of Health and Social Sciences, Dalarna University, Falun, Sweden. Dala Sports Academy, Falun, Sweden..
    Heil, Daniel
    Department of Health and Human Development, Montana State University, Bozeman, USA..
    Malm, Christer
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Sports Medicine. Winternet, Boden, Sweden.
    Tonkonogi, Michail
    Department of Health and Social Sciences, Dalarna University, Falun, Sweden..
    Scaling maximal oxygen uptake to predict performance in elite-standard men cross-country skiers2013In: Journal of Sports Sciences, ISSN 0264-0414, E-ISSN 1466-447X, Vol. 31, no 16, p. 1753-1760Article in journal (Refereed)
    Abstract [en]

    The purpose of this study was to: 1) establish the optimal body-mass exponent for maximal oxygen uptake (VO2max) to indicate performance in elite-standard men cross-country skiers; and 2) evaluate the influence of course inclination on the body-mass exponent. Twelve elite-standard men skiers completed an incremental treadmill roller-skiing test to determine VO2max and performance data came from the 2008 Swedish National Championship 15-km classic-technique race. Log-transformation of power-function models was used to predict skiing speeds. The optimal models were found to be: Race speed = 7.86 · VO2max · m (-0.48) and Section speed = 5.96 · VO2max · m (-(0.38 + 0.03 · α)) · e(-0.003 · Δ) (where m is body mass, α is the section's inclination and Δ is the altitude difference of the previous section), that explained 68% and 84% of the variance in skiing speed, respectively. A body-mass exponent of 0.48 (95% confidence interval: 0.19 to 0.77) best described VO2max as an indicator of performance in elite-standard men skiers. The confidence interval did not support the use of either "1" (simple ratio-standard scaled) or "0" (absolute expression) as body-mass exponents for expressing VO2max as an indicator of performance. Moreover, results suggest that course inclination increases the body-mass exponent for VO2max.

  • 108.
    Carlsson, Tomas
    et al.
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Sports Medicine. Department of Health and Social Sciences, Dalarna University, Falun, Sweden..
    Carlsson, Magnus
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Sports Medicine. Department of Health and Social Sciences, Dalarna University, Falun, Sweden..
    Hammarström, Daniel
    Department of Health and Social Sciences, Dalarna University, Falun, Sweden..
    Malm, Christer
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Sports Medicine. Winternet, Boden, Sweden..
    Tonkonogi, Michail
    Department of Health and Social Sciences, Dalarna University, Falun, Sweden. Olympiatoppen, Oslo, Norway..
    Scaling of upper-body power output to predict time-trial roller skiing performance2013In: Journal of Sports Sciences, ISSN 0264-0414, E-ISSN 1466-447X, Vol. 31, no 6, p. 582-588Article in journal (Refereed)
    Abstract [en]

    The purpose of the present study was to establish the most appropriate allometric model to predict mean skiing speed during a double-poling roller skiing time-trial using scaling of upper-body power output. Forty-five Swedish junior cross-country skiers (27 men and 18 women) of national and international standard were examined. The skiers, who had a body mass (m) of 69.3 +/- 8.0 kg (mean +/- s), completed a 120-s double-poling test on a ski ergometer to determine their mean upper-body power output (W). Performance data were subsequently obtained from a 2-km time-trial, using the double-poling technique, to establish mean roller skiing speed. A proportional allometric model was used to predict skiing speed. The optimal model was found to be: Skiing speed = 1.057 · W0.556 · m-0.315, which explained 58.8% of the variance in mean skiing speed (< 0.001). The 95% confidence intervals for the scaling factors ranged from 0.391 to 0.721 for W and from 0.626 to 0.004 for m. The results in this study suggest that allometric scaling of upper-body power output is preferable for the prediction of performance of junior cross-country skiers rather than absolute expression or simple ratio-standard scaling of upper-body power output.

  • 109.
    Carlsson, Tomas
    et al.
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Sports Medicine. School of Education, Health and Social Studies, Dalarna University, Falun, Sweden..
    Carlsson, Magnus
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Sports Medicine. School of Education, Health and Social Studies, Dalarna University, Falun, Sweden..
    Hammarström, Daniel
    The Lillehammer Research Center for Medicine and Exercise Physiology, Lillehammer University College, Lillehammer, Norway..
    Rønnestad, Bent
    The Lillehammer Research Center for Medicine and Exercise Physiology, Lillehammer University College, Lillehammer, Norway..
    Malm, Christer
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Sports Medicine.
    Tonkonogi, Michail
    School of Education, Health and Social Studies, Dalarna University, Falun, Sweden..
    Optimal V̇O2max-to-mass ratio for predicting 15-km performance among elite male cross-country skiersManuscript (preprint) (Other academic)
  • 110.
    Carlström, Andreas
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Sports Medicine.
    Enhanced peak oxygen consumption and fat oxidation following resistance training with emphasis on muscular hypertrophy2012Independent thesis Advanced level (degree of Master (One Year)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Heavy resistance training is generally associated with muscle hypertrophy and increases in muscular strength and anaerobic capacity. However, the adaptive response in aerobic metabolism is less investigated. The purpose of the present study was therefore to evaluate the effects of heavy resistance training on peak oxygen consumption (VO2peak), rate of fat oxidation during exercise and oxidative enzyme activity. Nineteen healthy young men volunteered to participate in the study. During eight weeks, the subjects performed supervised heavy resistance training with emphasis on muscular hypertrophy. Before and after the training intervention, body composition was assessed by dual energy X-ray absorptiometry and a graded incremental exercise test on a cycle ergometer was performed in order to determine VO2peak and fat oxidation kinetics. Further, skeletal muscle biopsies were taken from m. vastus lateralis before and after training to analyze the activity of the oxidative enzymes citrate synthase (CS) and β-hydroxyacyl-CoA dehydrogenase (β-HAD). The results of the study indicate that heavy resistance training induced major effects on cardiorespiratory capacity (p <0.001) and submaximal substrate utilization (p <0.001) despite no significant changes in oxidative enzyme activity (CS and β-HAD). Instead, part of the increases in VO2peak and rate of fat oxidation may be due to skeletal muscle hypertrophy and neuromuscular adaptations manifested by an increased work economy on the cycle ergometer.

  • 111.
    Chorell, Elin
    et al.
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Moritz, Thomas
    Branth, Stefan
    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.
    A predictive metabolomics evaluation of nutrition-modulated metabolic stress responses in human blood serum during the early recovery phase of strenuous physical exercise2009In: Journal of Proteome Research, ISSN 1535-3893, E-ISSN 1535-3907, Vol. 8, no 6, p. 2966-77Article in journal (Refereed)
    Abstract [en]

    We have investigated whether postexercise ingestion of carbohydrates in combination with proteins generates a different systemic metabolic response, as compared to the sole ingestion of carbohydrate or water, in the early recovery phase following exercise. In addition, metabolic patterns related to fitness level were studied together with individual responses to nutritional modulation. Twenty-four male subjects were exposed to 90 min of ergometer-cycling. Each participant was subject to four identical test-sessions, including ingestion of one of four beverages (water, low-carbohydrate beverage, high-carbohydrate beverage, and low-carbohydrate−protein beverage (LCHO-P)) immediately after cycling. Blood was collected at six time points, one pre- and five postexercise. Extracted blood serum was subject to metabolomic characterization by gas chromatography/time-of-flight mass spectrometry (GC−TOF MS). Data was processed using hierarchical multivariate curve resolution (HMCR), and multivariate statistical analysis was carried out using orthogonal partial least-squares (OPLS). Predictive metabolomics, including predictive HMCR and OPLS classification, was applied to ensure efficient sample processing and validation of detected metabolic patterns. Separation of subjects in relation to ingested beverage was detected and interpreted. Pseudouridine was suggested as a novel marker for pro-anabolic effect following LCHO-P ingestion, which was supported by the detected decrease of the catabolic marker 3-methylhistidine. Separation of subjects according to fitness level was achieved, and nutritional modulation by LCHO-P was shown to improve the metabolic status of less fit subjects in the recovery phase. In addition, the potential of the methodology for detection of early signs of insulin resistance was also demonstrated.

  • 112.
    Chorell, Elin
    et al.
    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.
    Moritz, Thomas
    Swedish University of Agricultural Sciences.
    Antti, Henrik
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Physical fitness level is reflected by alterations in the human plasma metabolome2012In: Molecular BioSystems, ISSN 1742-206X, Vol. 8, no 4, p. 1187-1196Article in journal (Refereed)
    Abstract [en]

    An excessive energy intake combined with a low level of physical activity induces detrimental processes involved in disease development, e.g. type 2 diabetes and cardiovascular disease. However the underlying mechanisms for regulation of metabolic capacity and fitness status remain unclear. Metabolomics involves global studies of the metabolic reactions in an organism or cell. Thus hypotheses regarding biochemical events can be generated to increase the understanding of disease development and thereby aid in the development of novel treatments or preventions. We present the first standardized intervention study focusing on characterizing the human metabolome in relation to moderate differences in cardiorespiratory fitness. Gas chromatography-time of flight/mass spectrometry (GC-TOF/MS) was used to characterize 460 plasma samples from 27 individuals divided into two groups based on physical fitness level (VO2max). Multi- and univariate between group comparisons based on 197 metabolites were carried out in samples collected at rest prior to any intervention, over time following a nutritional load or a standardized exercise scheme, with and without nutritional load. We detected decreased levels of gamma-tocopherol (GT), a vitamin E isomer, in response to a high fitness level, whereas the opposite was seen for the alpha isomer (AT). In addition, the high fitness level was associated with elevated ω3-PUFA (DHA, 22:6ω3) and a decrease in ω6-PUFA (18:2ω6) as well as in saturated (16:0, 18:0), monounsaturated (18:1) and trans (16:1) fatty acids. We thus hypothesize that high fitness status induces an increased cardiorespiratory inflammatory and antioxidant defense system, more prone to deal with the inflammatory response following exercise and nutrition intake.

  • 113.
    Chorell, Elin
    et al.
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Thysell, Elin
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Jonsson, Pär
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Eklund, Caroline
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences.
    Silfver, Anders
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences.
    Carlsson, Inga-Britt
    Umeå University, Faculty of Science and Technology, Umeå Plant Science Centre (UPSC).
    Lundgren, Krister
    Umeå University, Faculty of Science and Technology, Umeå Plant Science Centre (UPSC).
    Moritz, Thomas
    Umeå University, Faculty of Science and Technology, Umeå Plant Science Centre (UPSC).
    Svensson, Michael
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Sports Medicine.
    Antti, Henrik
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    A Multivariate Screening Strategy for Investigating Metabolic Effects of Strenuous Physical Exercise in Human Serum2007In: Journal of Proteome Research, ISSN 1535-3893, Vol. 6, no 6, p. 2113-2120Article in journal (Refereed)
    Abstract [en]

    A novel hypothesis-free multivariate screening methodology for the study of human exercise metabolism in blood serum is presented. Serum gas chromatography/time-of-flight mass spectrometry (GC/TOFMS) data was processed using hierarchical multivariate curve resolution (H-MCR), and orthogonal partial least-squares discriminant analysis (OPLS-DA) was used to model the systematic variation related to the acute effect of strenuous exercise. Potential metabolic biomarkers were identified using data base comparisons. Extensive validation was carried out including predictive H-MCR, 7-fold full cross-validation, and predictions for the OPLS-DA model, variable permutation for highlighting interesting metabolites, and pairwise t tests for examining the significance of metabolites. The concentration changes of potential biomarkers were verified in the raw GC/TOFMS data. In total, 420 potential metabolites were resolved in the serum samples. On the basis of the relative concentrations of the 420 resolved metabolites, a valid multivariate model for the difference between pre- and post-exercise subjects was obtained. A total of 34 metabolites were highlighted as potential biomarkers, all statistically significant (p < 8.1E-05). As an example, two potential markers were identified as glycerol and asparagine. The concentration changes for these two metabolites were also verified in the raw GC/TOFMS data.The strategy was shown to facilitate interpretation and validation of metabolic interactions in human serum as well as revealing the identity of potential markers for known or novel mechanisms of human exercise physiology. The multivariate way of addressing metabolism studies can help to increase the understanding of the integrative biology behind, as well as unravel new mechanistic explanations in relation to, exercise physiology.

  • 114.
    Chorell, Simon
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Sports Medicine.
    Fettoxidationens påverkan av maxstyrketräning2012Independent thesis Advanced level (degree of Master (One Year)), 20 credits / 30 HE creditsStudent thesis
    Abstract [sv]

    Abstrakt

    Styrketräning är en mycket viktig delkomponent i den nutida tävlingsidrotten, dels viktigt för att förebygga överbelastningsskador och dels för att uppnå optimal prestationsutveckling. De flesta elitidrottare lägger ner många träningstimmar och det krävs en bra planering för att kunna träna upp alla de delkapciteter som krävs för att förbättra prestationen inom en viss idrott. Inom uthållighetsidrotter genomförs styrketräningen ofta tillsammans med eller i anslutning till träning av de aeroba delkapaciteterna. Syftet med denna studie är att kartlägga effekten av tung styrketräning på muskulaturens aeroba metabolism vid ergometercykelarbete.

    Metod 

    Maxstyrka, VO2max och HLa mättes på fem manliga testpersoner, samtliga födda 1986. Därefter utfördes en fyra veckor lång träningsperiod med 7 pass av tung styrketräning. Passen bestod av enbart tung styrketräning för mage, höft och ben. Efter träningsperioden mättes samtliga faktorer igen för att jämföras med de tidigare resultaten.

    Huvudsakliga resultat

    Det huvudsakliga fyndet i den genomförda studien visar tydligt att sju pass av maxstyrketräning försämrade både VO2max och fettoxidationen men förbättrar samtidigt styrkan avsevärt.

    Konklussion

    Slutsatser baserade på den här studiens resultat är att det inte optimalt att träna tung styrketräning med avsikt att öka den aeroba metabolismen i muskulaturen för elitidrottare. Att träna tre set med få repetitioner och en längre vila ger en mycket bra ökning i styrka.

    Sökord

    Heavy resisance tranining, concurrent strength and endurance training, neuromuscular adaptations, concurrent exercise, heavy strength training.

  • 115. Cotgreave, Ian A
    et al.
    Goldschmidt, Lina
    Tonkonogi, Michail
    Svensson, Michael
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Sports Medicine.
    Differentiation-specific alterations to glutathione synthesis in and hormonally stimulated release from human skeletal muscle cells.2002In: The FASEB Journal, ISSN 0892-6638, E-ISSN 1530-6860, Vol. 16, no 3, p. 435-7Article in journal (Refereed)
    Abstract [en]

    Muscle atrophy and cachexia are associated with many human diseases. These catabolic states are often associated with the loss of glutathione (GSH), which is thought to contribute to the induction of oxidative stress within the muscle. Glutathione synthesis and secretary characteristics were studied in human skeletal muscle myoblasts and myotube-like cells derived from the myoblasts by growth factor restriction. Differentiation was associated with a shift in the sulfur amino acid precursor specificity for synthesis of GSH from cystine to cysteine, as well as loss in ability to use extracellular glutathione and activation of methionine use. The thiol drug N-acetylcysteine was also shown to be an effective precursor irrespective of the state of differentiation. Additionally, myoblasts and myotube cultures were shown to secrete GSH continually, but only the differentiated cells responded to stress hormones such as glucagon, vasopressin, and phenylephrine, by increased secretion of the tripeptide. The data suggest that the skeletal muscle cells may provide an important hormonally regulated extra-hepatic source of systemic GSH and also shed light on the mechanisms of accelerated turnover of GSH operating during strenuous muscle activity and trauma. The data may also provide biochemical rationales for the nutritional and/or pharmacological manipulation of GSH with sulfur amino acid precursors during the treatment of muscle-specific oxidative stress and atrophy.

  • 116. Crenshaw, Albert G
    et al.
    Lyskov, Eugene
    Heiden, Marina
    Flodgren, Gerd
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Sports Medicine. Centre for Musculoskeletal Research, University of Gävle, Umeå, Sweden.
    Hellström, Fredrik
    Impact of time pressure and pauses on physiological responses to standardized computer mouse use: a review of three papers focusing on mechanisms behind computer-related disorders2007In: Scandinavian Journal of Work, Environment and Health, ISSN 0355-3140, E-ISSN 1795-990X, no Suppl 3, p. 68-75Article in journal (Refereed)
    Abstract [en]

    This paper reviews three computer mouse studies in our laboratory in which our emphasis was on mechanisms behind computer-related disorders. Our approach was sequentially (i) to determine the validity of a laboratory model for computer mouse use (painting rectangles) for studying musculoskeletal disorders, (ii) to use this model to study time pressure and precision demands on position sense and muscular oxygenation, and (iii) to use this model to determine the effect of pauses (active versus passive) on these parameters. Kinematic data for the painting model showed constrained movements of the wrist similar to that of CAD (computer-aided design) work, a support for its validity for a real-life situation. Changes in forearm oxygenation were associated with time pressure and precision demands, a potential for insight into the underlying pathophysiological mechanisms. Increasing trends in oxygenation and blood volume were associated with pauses, especially active pauses, a possible explanation for the alleviating effect of discomfort experienced in real-life situations when a pause is implemented.

  • 117. Daerga, Laila
    et al.
    Edin-Liljegren, Anette
    Sjölander, Per
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Sports Medicine.
    Work-related musculoskeletal pain among reindeer herding Sami in Sweden--a pilot study on causes and prevention.2004In: Int J Circumpolar Health, ISSN 1239-9736, Vol. 63 Suppl 2, p. 343-8Article in journal (Refereed)
  • 118.
    Danielson, Patrik
    et al.
    Umeå University, Faculty of Medicine, Department of Integrative Medical Biology (IMB).
    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. Anatomi.
    Distribution of general (PGP 9.5) and sensory (substance P/CGRP) innervations in the human patellar tendon.2006In: Knee Surgery, Sports Traumatology, Arthroscopy, ISSN 0942-2056, E-ISSN 1433-7347, Vol. 14, no 2, p. 125-132Article in journal (Refereed)
    Abstract [en]

    There is no information on the pattern of blood vessel innervation, and in principle no information on innervation in general, in the human patellar tendon. In the present study, biopsies from the proximal part of normal and pain-free patellar tendons (11 men, mean age 33 years) were examined. The specimens were evaluated by using antibodies against the general nerve marker protein gene-product 9.5 (PGP 9.5) and the sensory neuropeptides substance P (SP) and calcitonin gene-related peptide (CGRP), and immunohistochemistry. It was observed that the arteries, and to some extent the small vessels, in the loose paratendinous connective tissue were supplied with PGP 9.5- as well as SP- and CGRP-innervations. There was a marked PGP 9.5-like immunoreaction (LI), and to some extent also SP- and CGRP-LI, in the large nerve fascicles in this tissue. In the tendon tissue proper, PGP 9.5-LI was detected in nerve fibers located in the vicinity of some of the blood vessels and in thin nerve fascicles. There was a low degree of SP- and CGRP-innervation in the tendon tissue proper. The observations give a morphologic correlate for the occurrence of nerve-mediated effects in the patellar tendon. Particularly it seems as if there is a marked nerve-mediated regulation of the blood vessels supplying the tendon, at the level where they course in the loose paratendinous connective tissue.

  • 119.
    Danielson, Patrik
    et al.
    Umeå University, Faculty of Medicine, Department of Integrative Medical Biology (IMB), Anatomy.
    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.
    Extensive expression of markers for acetylcholine synthesis and of M2 receptors in tenocytes in therapy-resistant chronic painful patellar tendon tendonosis - a case study2006Conference paper (Refereed)
    Abstract [en]

    We have recently, in a study of a group of patients with chronic painful patellar tendon tendinosis (“jumper’s knee”), obtained evidence favoring the occurrence of an upregulation of a non-neuronal cholinergic system in this condition. Today, there is a new line of treatment of patellar tendinosis in the form of doppler guided sclerosing injections (Polidokanol), a treatment that has turned out to be very successful. However, the mechanisms for this therapy remain somewhat unclear. After an average of three treatments, a majority of the patients experience a significant decrease of pain symptoms. Nevertheless, a few patients seem resistant to this therapy, exhibiting no clear decrease in pain sensation.

    Therefore, we have in this pilot study investigated biopsies from the patellar tendon of one such therapy-resistant patient (male, exhibiting long duration of pain symptoms and showing radiological findings confirming tendinosis), using immunohistochemical methods examining both chemically fixed and unfixed tissue. The results were compared with our previous findings of both normal and tendinosis tendons.

    Morphologically, there was hypercellularity in the tendon tissue. The immunohistochemical studies showed that there were marked immunoreactions for choline acetyltransferase (ChAT) and vesicular acetylcholine transporter (VAChT) (fixed tissue), as well as for the M2 muscarinic acetylcholine receptor (unfixed tissue), in the overwhelming majority of the tenocytes. The levels of immunoreactions were more pronounced than those obtained in the tendinosis tissue of the previously studied patients and clearly more pronounced than those of tendon tissue of controls.

    In conclusion, our theory is that cases of severe tendinosis, exhibiting therapy-resistance, are related to the occurrence of an excessive local acetylcholine (ACh) production that appears to be even more prominent than in tendinosis in general. This case study emphasizes the need for further investigation regarding the role of non-neuronal ACh in therapy-resistant patellar tendon tendinosis.

  • 120.
    Danielson, Patrik
    et al.
    Umeå University, Faculty of Medicine, Department of Integrative Medical Biology (IMB), Anatomy.
    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.
    Findings favoring production of non-neuronal acetylcholine with possible autocrine/paracrine effects in chronic painful patellar tendon tendinosis.2006Conference paper (Refereed)
    Abstract [en]

    The innervation pattern of the human patellar tendon is largely unknown. That includes the situation for patients suffering from patellar tendon tendinosis (“jumper’s knee”). Concerning the possible occurrence of a cholinergic system in the human patellar tendon, very little information is available.

    In the present study, specimens of pain-free normal (n=16) and chronically painful tendinosis (n=7) tendons were examined by different immunohistochemical and histochemical methods.

    It was found that parts of the tenocytes of the tendinosis tendons displayed immunoreactions for choline acetyltransferase (ChAT) and vesicular acetylcholine transporter (VAChT). Furthermore, immunoreactions for the M2 muscarinic acetylcholine receptor could be detected in both blood vessel cells and tenocytes, especially in tendinosis specimens. Acetylcholinesterase activity was shown for scarce nerve fibers associated with small blood vessels in both the normal and the tendinosis tendons.

    The observations suggest that, besides the occurrence of a scanty nerve related cholinergic system in the human patellar tendon, there is a local non-neuronal cholinergic system as well, at least in tendinosis tendons. As ChAT and VAChT were detected in tenocytes of these tendons, such tenocytes are likely to produce acetylcholine (ACh) locally, and as both tenocytes and blood vessel cells were found to express the M2 receptor, it is likely that both of these cell types may be influenced by ACh.

    Thus, in conclusion, there appears to be an upregulation of the cholinergic system, and an occurrence of autocrine/paracrine effects in this system, in the tendinosis patellar tendon. This observation is of importance, not only related to the fact that tendinosis patients exhibit marked pain, but also as stimulation of ACh receptors can lead to cell proliferation, effects on collagen accumulation and angiogenesis, all of which are phenomena that occur in tendinosis.

  • 121.
    Danielson, Patrik
    et al.
    Umeå University, Faculty of Medicine, Department of Integrative Medical Biology (IMB), Anatomy.
    Alfredson, Håkan
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Sports Medicine. Idrottsmedicin.
    Forsgren, Sture
    Umeå University, Faculty of Medicine, Department of Integrative Medical Biology (IMB), Anatomy. Anatomi.
    Immunohistochemical and histochemical findings favoring the occurrence of autocrine/paracrine as well as nerve-related cholinergic effects in chronic painful patellar tendon tendinosis.2006In: Microscopy research and technique (Print), ISSN 1059-910X, E-ISSN 1097-0029, Vol. 69, no 10, p. 808-819Article in journal (Refereed)
    Abstract [en]

    The pathogenesis of the pain in patellar tendon tendinosis ("jumper's knee") is unclear. We have recently presented new information about the sensory nervous system in the human patellar tendon, but there is very little information regarding the possible occurrence of a cholinergic system in this tendon. In the present study, specimens of pain-free normal tendons and chronically painful tendinosis tendons were examined by different immunohistochemical and histochemical methods. Antibodies against the M(2) receptor, choline acetyltransferase (ChAT), and vesicular acetylcholine transporter (VAChT) were applied, and staining for demonstration of activity of acetylcholinesterase (AChE) was also utilized. It was found that immunoreactions for the M(2) receptor could be detected intracellularly in both blood vessel cells and tenocytes, especially in tendinosis specimens. Furthermore, in the tendinosis specimens, some tenocytes were seen to exhibit immunoreaction for ChAT and VAChT. AChE reactions were seen in fine nerve fibers associated with small blood vessels in both the normal control tendons and the tendinosis tendons. The observations suggest that there is both a nerve related and a local cholinergic system in the human patellar tendon. As ChAT and VAChT immunoreactions were detected in tenocytes of tendinosis tendons, these cells might be a source of local acetylcholine (Ach) production. As both tenocytes and blood vessel cells were found to exhibit immunoreactions for the M(2) receptor, it is likely that both of these tissue cells may be influenced by ACh. Thus, in conclusion, there appears to be an upregulation of the cholinergic system, and an occurrence of autocrine/paracrine effects in this system, in the tendinosis patellar tendon.

  • 122.
    Danielson, Patrik
    et al.
    Umeå University, Faculty of Medicine, Department of Integrative Medical Biology (IMB), Anatomy.
    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.
    In situ hybridization studies confirming recent findings of the existence of a local nonneuronal catecholamine production in human patellar tendinosis.2007In: Microscopy research and technique (Print), ISSN 1059-910X, E-ISSN 1097-0029, Vol. 70, no 10, p. 908-911Article in journal (Other academic)
    Abstract [en]

    We have in recent studies presented unexpected immunohistochemical evidence favoring the existence of a local production of catecholamines, and an occurrence of adrenergic receptors on the tendon cells (tenocytes), in the human patellar tendon. This was particularly noticed for tendons from patients suffering from tendinosis (chronic tendon pain), which has led us to propose an involvement of this autocrine/paracrine system in the development of tendinosis, especially since catecholamines have been reported to be modulators of tissue remodeling and pain processes. However, the findings concerning catecholamine production have so far only been noted at the level of protein detection, and for this reason, the aim of the present study was to confirm the previous immunohistochemical results by using in situ hybridization (ISH) technique. A ssDNA probe detecting human mRNA for the catecholamine-synthesizing enzyme tyrosine hydroxylase (TH) was applied. The ISH results revealed that there were clear reactions indicating the existence of mRNA for TH in tenocytes of tendinosis specimens. It was generally noted that disfigured tenocytes were the ones with the most distinct reactions, while normally looking tenocytes hardly displayed any reactions at all. In conclusion, this study presents the first evidence at the mRNA level of the existence of a local nonneuronal production of catecholamines in human patellar tendon tissue. The findings add to recent observations of the occurrence of a local production in tendons of signal substances traditionally related to neurons.

    (c) 2007 Wiley-Liss, Inc.

  • 123.
    Danielson, Patrik
    et al.
    Umeå University, Faculty of Medicine, Department of Integrative Medical Biology (IMB), Anatomy.
    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.
    Marked occurrence of receptors for sympathetic and cholinergic transmitters and for substance P in the blood vessels of the human patellar tendon.2005Conference paper (Refereed)
    Abstract [en]

    INTRODUCTION: Human tendons have generally been considered to be hyponeural. However, in our recent studies of the patellar tendon in both healthy individuals and patients with tendinosis (jumper’s knee), we have noted the presence of general (PGP 9.5) and sensory (substance P [SP]) innervations, especially in the loose paratendinous connective tissue. Furthermore, we have observed a pronounced expression of the neurokinin-1 receptor (the preferred receptor for SP) in blood vessel walls. The findings are of interest as a new successful treatment of tendinosis has emerged in form of doppler guided sclerosing injections (substance: Polidokanol), targeting areas with neovascularisation, and as SP is known to be of importance when neurogenic angiogenesis participates in diseases. AIM: To further investigate the blood vessels of the normal and tendinosis-affected human patellar tendon regarding autonomic innervation. METHODS: Immunohistochemistry and histochemistry, including antibodies against the sympathetic nerve markers tyroxine hydroxylase and neuropeptide Y and against various adrenoreceptors (α1, α2a, β1), as well as stainings for substances related to cholinergic functions such as the muscarinic M2 receptor, acetylcholinesterase and vesicular acetylcholine transporter. RESULTS/CONCLUSIONS: The preliminary results so far, indicate that there is indeed an occurrence of both sympathetic and cholinergic innervations in the tendon, not the least shown via the presence of sympathetic and cholinergic receptors in blood vessel walls; a fact that further supports the theories that blood vessel regulation via neurotransmitters/-modulators might be a key factor in the pathological mechanisms of jumper’s knee.

  • 124.
    Danielson, Patrik
    et al.
    Umeå University, Faculty of Medicine, Department of Integrative Medical Biology (IMB), Anatomy. Anatomi.
    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. Anatomi.
    Studies on the importance of sympathetic innervation, adrenergic receptors, and a possible local catecholamine production in the development of patellar tendinopathy (tendinosis) in man.2007In: Microscopy research and technique (Print), ISSN 1059-910X, E-ISSN 1097-0029, Vol. 70, no 4, p. 310-324Article in journal (Refereed)
    Abstract [en]

    Changes in the patterns of production and in the effects of signal substances may be involved in the development of tendinosis, a chronic condition of pain in human tendons. There is no previous information concerning the patterns of sympathetic innervation in the human patellar tendon. In this study, biopsies of normal and tendinosis patellar tendons were investigated with immunohistochemical methods, including the use of antibodies against tyrosine hydroxylase (TH) and neuropeptide Y, and against alpha(1)-, alpha(2A)-, and beta(1)-adrenoreceptors. It was noticed that most of the sympathetic innervation was detected in the walls of the blood vessels entering the tendon through the paratendinous tissue, and that the tendon tissue proper of the normal and tendinosis tendons was very scarcely innervated. Immunoreactions for adrenergic receptors were noticed in nerve fascicles containing both sensory and sympathetic nerve fibers. High levels of these receptors were also detected in the blood vessel walls; alpha(1)-adrenoreceptor immunoreactions being clearly more pronounced in the tendinosis tendons than in the tendons of controls. Interestingly, immunoreactions for adrenergic receptors and TH were noted for the tendon cells (tenocytes), especially in tendinosis tendons. The findings give a morphological correlate for the occurrence of sympathetically mediated effects in the patellar tendon and autocrine/paracrine catecholamine mechanisms for the tenocytes, particularly, in tendinosis. The observation of adrenergic receptors on tenocytes is interesting, as stimulation of these receptors can lead to cell proliferation, degeneration, and apoptosis, events which are all known to occur in tendinosis. Furthermore, the results imply that a possible source of catecholamine production might be the tenocytes themselves. Microsc. Res. Tech., 2007. (c) 2007 Wiley-Liss, Inc.

  • 125.
    Danielson, Patrik
    et al.
    Umeå University, Faculty of Medicine, Department of Integrative Medical Biology (IMB), Anatomy. Anatomi.
    Andersson, Gustav
    Umeå University, Faculty of Medicine, Department of Integrative Medical Biology (IMB), Anatomy.
    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. Anatomi.
    Extensive expression of markers for acetylcholine synthesis and of M2 receptors in tenocytes in therapy-resistant chronic painful patellar tendon tendinosis - a pilot study.2007In: Life Sciences, ISSN 0024-3205, E-ISSN 1879-0631, Vol. 80, no 24-25, p. 2235-2238Article in journal (Refereed)
    Abstract [en]

    We have recently obtained evidence favoring the occurrence of an up-regulation of a non-neuronal cholinergic system in chronic painful patellar tendon tendinosis. It seems possible that this up-regulation to a certain degree may be involved in the manifestations of the disease. Today, there is a new, very successful, line of treatment of patellar tendinosis in the form of Doppler guided sclerosing injections. However, a few patients seem resistant to this therapy. Therefore, we have in this pilot study investigated biopsies from the patellar tendon of three such therapy-resistant patients, using immunohistochemistry. In situ hybridization was also applied. Comparisons were made with a material of specimens from both normal (n=16) and tendinosis (n=7) tendons, also previously examined. The study showed that there were extensive immunoreactions for choline acetyltransferase (ChAT) and vesicular acetylcholine transporter, as well as for the M(2) muscarinic acetylcholine receptor, in the overwhelming majority of the tenocytes. The immunoreactions were more pronounced than those generally obtained in the tendinosis tissue of the previously studied patients and clearly more pronounced than those of patellar tendon tissue of controls. Also, for the first time, we here present findings of mRNA for ChAT within tenocytes. In conclusion, it appears as if there is an excessive local acetylcholine (ACh) production and an occurrence of marked ACh effects in cases of severe tendinosis. An excessive production of local ACh might be related to pain sensation and the processes that occur in tendinosis development, such as cell proliferation. Thus, the results of this pilot study suggest that non-neuronal ACh is highly involved in the pathology of therapy-resistant patellar tendinosis.

  • 126.
    Danielson, Patrik
    et al.
    Umeå University, Faculty of Medicine, Department of Integrative Medical Biology (IMB), Anatomy.
    Andersson, Gustav
    Umeå University, Faculty of Medicine, Department of Integrative Medical Biology (IMB), Anatomy.
    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.
    Marked sympathetic component in the perivascular innervation of the dorsal paratendinous tissue of the patellar tendon in arthroscopically treated tendinosis patients.2008In: Knee Surgery, Sports Traumatology, Arthroscopy, ISSN 0942-2056, E-ISSN 1433-7347, Vol. 16, no 6, p. 621-6Article in journal (Refereed)
    Abstract [en]

    During the recent years, a few studies have shed new light on the innervation patterns of the human patellar tendon, but the area of the loose paratendinous connective tissue dorsal to the proximal tendon proper has yet not been investigated. That is a drawback, since this is the area targeted in promising treatment regimens of chronic painful patellar tendinosis, namely sclerosing Polidocanol injection therapy, and a new surgical method conforming to ultrasound and color Doppler guided arthroscopic shaving, directed at neovessels found in the region. The present study thus aimed at investigating the paratendinous area dorsal to the proximal patellar tendon proper in seven patients being operated for tendinosis. Biopsies were collected through the new arthroscopic technique, approaching the tendon from the dorsal side. Samples were investigated using immunohistochemistry with antibodies delineating general (PGP 9.5), sensory (SP/CGRP), and sympathetic (TH/NPY) nerve patterns, and also antibodies against alpha1- and alpha2A-adrenoreceptors. Both small and large blood vessels had a marked perivascular innervation (PGP 9.5). Surprisingly, this perivascular innervation was found only to a very limited extent to correspond to sensory nerves, while there were marked immunoreactions for sympathetic markers. Adrenoreceptor immunoreactions frequently occurred in blood vessel walls. In conclusion, this study demonstrates, for the first time, the innervation patterns of the area dorsal to the patellar tendon in man. It shows that the area investigated is under marked influence by the sympathetic nervous system. Thus, sympathetic effects are likely to occur for blood vessels of the area, which is interesting since color Doppler has revealed that vessels of this area ("neovessels") display a pathologically high blood flow in tendinosis. The findings are discussed in relation to aspects of vascular regulation, and to pain symptoms of tendinosis.

  • 127. Djupsjöbacka, Mats
    et al.
    Domkin, Dmitry
    Umeå University, Faculty of Medicine, Surgical and Perioperative Sciences, Sports Medicine.
    Correlation analysis of proprioceptive acuity in ipsilateral position-matching and velocity-discrimination.2005In: Somatosensory & motor research, ISSN 0899-0220, E-ISSN 1369-1651, ISSN 0899-0220, Vol. 22, no 1-2, p. 85-93Article in journal (Refereed)
    Abstract [en]

    In order to plan and control movements the central nervous system (CNS) needs to continuously keep track of the state of the musculoskeletal system. Therefore the CNS constantly uses sensory input from mechanoreceptors in muscles, joints and skin to update information about body configuration on different levels of the CNS. On the conscious level, such representations constitute proprioception. Different tests for assessment of proprioceptive acuity have been described. However, it is unclear if the proprioceptive acuity measurements in these tests correlate within subjects. By using both uni- and multivariate analysis we compared proprioceptive acuity in different variants of ipsilateral active and passive limb position-matching and ipsilateral passive limb movement velocity-discrimination in a group of healthy subjects. The analysis of the position-matching data revealed a higher acuity of matching for active movements in comparison to passive ones. The acuity of matching was negatively correlated to movement extent. There was a lack of correlation between proprioceptive acuity measurements in position-matching and velocity-discrimination.

  • 128.
    Domkin, Dmitry
    et al.
    Umeå University, Faculty of Medicine, Surgical and Perioperative Sciences, Sports Medicine.
    Laczko, Jozsef
    Djupsjöbacka, Mats
    Jaric, Slobodan
    Latash, Mark L
    Joint angle variability in 3D bimanual pointing: uncontrolled manifold analysis.2005In: Experimental Brain Research, ISSN 0014-4819, E-ISSN 1432-1106, Vol. 163, no 1, p. 44-57Article in journal (Refereed)
    Abstract [en]

    The structure of joint angle variability and its changes with practice were investigated using the uncontrolled manifold (UCM) computational approach. Subjects performed fast and accurate bimanual pointing movements in 3D space, trying to match the tip of a pointer, held in the right hand, with the tip of one of three different targets, held in the left hand during a pre-test, several practice sessions and a post-test. The prediction of the UCM approach about the structuring of joint angle variance for selective stabilization of important task variables was tested with respect to selective stabilization of time series of the vectorial distance between the pointer and aimed target tips (bimanual control hypothesis) and with respect to selective stabilization of the endpoint trajectory of each arm (unimanual control hypothesis). The components of the total joint angle variance not affecting (V(COMP)) and affecting (V(UN)) the value of a selected task variable were computed for each 10% of the normalized movement time. The ratio of these two components R(V)=V(COMP)/V(UN) served as a quantitative index of selective stabilization. Both the bimanual and unimanual control hypotheses were supported, however the R(V) values for the bimanual hypothesis were significantly higher than those for the unimanual hypothesis applied to the left and right arm both prior to and after practice. This suggests that the CNS stabilizes the relative trajectory of one endpoint with respect to the other more than it stabilizes the trajectories of each of the endpoints in the external space. Practice-associated improvement in both movement speed and accuracy was accompanied by counter-intuitive lack of changes in R(V). Both V(COMP) and V(UN) variance components decreased such that their ratio remained constant prior to and after practice. We conclude that the UCM approach offers a unique and under-explored opportunity to track changes in the organization of multi-effector systems with practice and allows quantitative assessment of the degree of stabilization of selected performance variables.

  • 129.
    Domkin, Dmitry
    et al.
    Umeå University, Faculty of Medicine, Surgical and Perioperative Sciences, Sports Medicine.
    Laczko, Jozsef
    Jaric, Slobodan
    Johansson, Håkan
    Latash, Mark
    Structure of joint variability in bimanual pointing tasks2002In: Experimental Brain Research, ISSN 0014-4819, E-ISSN 1432-1106, Vol. 143, no 1, p. 11-23Article in journal (Refereed)
    Abstract [en]

    Changes in the structure of motor variability during practicing a bimanual pointing task were investigated using the framework of the uncontrolled manifold (UCM) hypothesis. The subjects performed fast and accurate planar movements with both arms, one moving the pointer and the other moving the target. The UCM hypothesis predicts that joint kinematic variability will be structured to selectively stabilize important task variables. This prediction was tested with respect to selective stabilization of the trajectory of the endpoint of each arm (unimanual control hypotheses) and with respect to selective stabilization of the timecourse of the vectorial distance between the target and the pointer tip (bimanual control hypothesis). Components of joint position variance not affecting and affecting a mean value of a selected variable were computed at each 10% of normalized movement time. The ratio of these two components ( R(V)) served as a quantitative index of selective stabilization. Both unimanual control hypotheses and the bimanual control hypothesis were supported both prior to and after practice. However, the R(V) values for the bimanual control hypothesis were significantly higher than for either of the unimanual control hypothesis, suggesting that the bimanual synergy was not simply a simultaneous execution of two unimanual synergies. After practice, an improvement in both movement speed and accuracy was accompanied by counterintuitive changes in the structure of kinematic variability. Components of joint position variance affecting and not affecting a mean value of a selected variable decreased, but there was a significantly larger drop in the latter when applied on each of the three selected task variables corresponding to the three control hypotheses. We conclude that the UCM hypothesis allows quantitative assessment of the degree of stabilization of selected performance variables and provides information on changes in the structure of a multijoint synergy that may not be reflected in its overall performance.

  • 130. Edin-Liljegren, A
    et al.
    Hassler, Sven
    Umeå University, Faculty of Medicine, Public Health and Clinical Medicine, Epidemiology and Public Health Sciences.
    Sjölander, Per
    Umeå University, Faculty of Medicine, Surgical and Perioperative Sciences, Sports Medicine.
    Daerga, L
    Risk factors for cardiovascular diseases among Swedish Sami: a controlled cohort study2004In: International Journal of Circumpolar Health, ISSN 1239-9736, E-ISSN 2242-3982, Vol. 63, no Suppl 2, p. 292-297Article in journal (Refereed)
    Abstract [en]

    OBJECTIVE: To investigate the occurrence of clinical, psychosocial and behavioural risk factors for cardiovascular diseases (CVD) among reindeer herding (RS) and non-reindeer herding Sami (NRS). STUDY DESIGN: A retrospective cohort study, comparing risk factors behind CVD between Sami and non-Sami, RS and NRS, and Sami men and women. METHODS: A cohort of 611 Swedish Sami (276 men and 335 women) was constructed from national population registers. A twice as large control cohort of non-Sami was created, matched by age, gender and area of residence. Information on risk factors was obtained from a database containing clinical and psychosocial-behavioural data from a regional CVD preventive programme for the period 1990-2001. RESULTS: The Sami and the non-Sami showed similar risk factor patterns. The main differences were related to working conditions and lifestyle factors of the RS. The RS men had lower blood pressure, were more physically active and had higher job demand and decision latitude. The RS women showed more negative scores on the indices of the job strain model. CONCLUSIONS: Previously reported differences in CVD mortality between Sami and non-Sami, and Sami men and women, can only partly be explained by different exposure to the psychosocial and behaviour risk factors investigated in this study.

  • 131. Ekblom, Örjan
    et al.
    Ekblom, Björn
    Malm, Christer
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Sports Medicine.
    Immunological alterations used to predict infections in response to strenuous physical training2011In: Military medicine, ISSN 0026-4075, E-ISSN 1930-613X, Vol. 176, no 7, p. 785-790Article in journal (Refereed)
    Abstract [en]

    The aim of this study was to screen leukocyte cell surface markers to identify possible predictors for infection related to physical training. Ten healthy soldiers (mean age, 19.1; mean body mass, 77.4 kg; mean VO2 peak, 4.54 L min(-1)/58.6 mL min(-1) kg(-1)) were included. Blood samples were collected and number of infections recorded before and after a 6-day training course. White blood cell distributions and expression of surface receptors changed during training. Before training, expression of CD3 on CD8+ lymphocytes and percent CD8+CD3 lymphocytes was lower, whereas CD4/CD8 ratio was higher among subjects who failed compared to those who completed the training. A subclinical infection before the start of the military training may alter the CD4/CD8 ratio. Prediction of future infections may be possible from pre-exercise immunological status, findings useful in military settings and exercise, where sudden infections may result in severe consequences.

  • 132.
    Eklund, Fredrik
    et al.
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Sports Medicine.
    Nordström, Anna
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Sports Medicine.
    Björnstig, Ulf
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Surgery.
    Nordström, Peter
    Umeå University, Faculty of Medicine, Department of Community Medicine and Rehabilitation, Geriatric Medicine.
    Bone mass, size and previous fractures as predictors of prospective fractures in an osteoporotic referral population.2009In: Bone, ISSN 8756-3282, E-ISSN 1873-2763, Vol. 45, no 4, p. 808-813Article in journal (Refereed)
    Abstract [en]

    The influence of bone mass, bone size and previous low energy fractures upon prospective fractures has not been investigated in a referral osteoporotic population. We investigated the association between bone mass, bone size, previous fractures, body constitution, and prospective validated fractures in 5701 women and 1376 men, aged 30 years and older. Bone mass measurements of the femoral neck were collected at a single study center in Sweden. Most of the subjects were measured on suspicion of osteoporosis. Data on validated low energy retrospective and prospective fractures in the cohort were collected from the corresponding health care district. Bone mineral density (BMD, g/cm(2)) and estimated volumetric BMD (vBMD, g/cm(3)) were shown to be good independent predictors for fracture in both women and men (Hazard ratio per standard deviation decrease (HR)=1.27-1.52, p<0.05). Bone size did not predict prospective fractures in either sex (HR=0.91-0.99, p>0.05), and bone size completely explained the higher BMD in men than in women. In women, retrospective low energy fractures (HR=1.78, p<0.001) and height (HR=1.02, p=0.006) were additional independent predictors of osteoporotic fractures after adjusting for age and BMD. In conclusion, we show that in a large osteoporotic referral population, age, BMD and previous fractures are independent predictors of prospective low energy fractures. These results add additional strength to the recent change in focus towards a multivariate analysis when assessing the future risk of fracture.

  • 133.
    Eklund, Fredrik
    et al.
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Sports Medicine.
    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, Rehabilitation Medicine.
    Neovius, Martin
    Svensson, Olle
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Orthopaedics.
    Nordström, Peter
    Umeå University, Faculty of Medicine, Department of Community Medicine and Rehabilitation, Geriatric Medicine.
    Variation in fracture rates by country may not be explained by differences in bone mass2009In: Calcified Tissue International, ISSN 0171-967X, E-ISSN 1432-0827, Vol. 85, no 1, p. 10-16Article in journal (Refereed)
    Abstract [en]

    It is unclear whether the high fracture incidence in Sweden compared with other countries is related to low bone mass. We present and compare bone mineral density (BMD, g/cm(2)) at the femoral neck in a mainly osteoporotic referral population consisting of 2,031 men and 6,932 women with that of previous population-based cohorts. BMD measurements were collected at a single study center in Sweden, and data on validated hip fractures were collected from the corresponding health-care district and the cohort investigated. The BMD values of our cohort were similar to those of population-based cohorts from other countries. In contrast, the total incidence of hip fractures in 80-year-old women and men in the health-care district where our BMD measurements were performed was high (1.8% and 0.9%, respectively). The correlation between age and BMD was more negative in men aged 20-49 years than in women of the same age group (-0.011 vs. -0.006 g/cm(2) yearly, P < 0.001). In contrast, at 50-80 years of age, more negative regression coefficients were seen in women (-0.007 vs. -0.004 g/cm(2) yearly, P < 0.001 for comparison). In conclusion, a low BMD may not be the key factor explaining Sweden's comparatively high fracture incidence. In our cross-sectional data, age trends in BMD at the femoral neck differ between men and women. It would be highly interesting to further study the underlying causes of the global variations in fracture incidence rates.

  • 134.
    Elmqvist, Lars-Gunnar
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Orthopaedics. 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.
    Chronic anterior cruciate ligament tear: knee function and knee extensor muscle size, morphology and function before and after surgical reconstruction1988Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Knee function was evaluated by knee score, activity level, clinical findings and performance tests, muscle size by computerized tomography (CT), morphology by light (LM) and electron microscopy (EM), muscle function by electromyography (EMG) and isokinetic performance in 29 patients with chronic anterior cruciate ligament (ACL) tear. Preoperatively CT disclosed a significant mean atrophy of the quadriceps and nonsignificant changes of the other muscle areas of the injured leg. Morphology of m vastus lateralis of the injured leg was normal in more than half of the biopsies preoperatively, the rest showed signs of nonoptimal activation. Significant decreases in all isokinetic parameters were noticed together with significantly decreased EMG of the quadriceps muscle of the injured leg.

    Âfter surgical reconstruction the knees were immobilized in a cast for 6 weeks at either 30° or 70° of knee flexion. After cast removal CT showed significant decreases of all areas which also remained after training. The 30° group showed larger fibres (intracellular oedema) and more frequent morphological abnormalities than the 70° group. Fourteen weeks postoperatively the patients were allocated to either a combination of isometric and progressive resistance training or isokinetic training for 6 weeks. CT showed slightly larger areas at 20 weeks postoperatively than at 6 weeks. Morphological abnormalities were still prominent at 20 weeks postoperatively. Maximum isokinetic knee extensor mechanical output and endurance were markedly decreased at 14 weeks postoperatively but both improved progressively during the one year rehabilitation, mostly during the intensive 6 week training period but irrespective of training programme used. Fatiguability/endurance level improved over the preoperative level. Muscular work/integrated EMG was stable while EMG/t increased indicating neuromuscular relearning.

    The clinical result at 28 months foliowup was excellent or good in 93% of the patients and clinical stability improved in 66%. Independent upon primary knee immobilization angle or training programmes no differences could be demonstrated with respect to stability, range of motion, function or isokinetic mechanical output. Isokinetic performance was still significantly lower in the injured compared to the noninjured leg and not significantly different from the preoperative values. Morphology, only 6 cases, showed abnormalities similar to preoperative findings.

    In conclusion, the reason for the decreased maximum and total knee extensor performance in these patients with ACL tears is suggested to be nonoptimal activation of normal functioning muscle fibres depending on changes in knee joint receptor afferent inflow. No differences concerning the markedly improved postoperative clinical result could be seen between the different treatment modalities used. A nonoptimal muscular activation might explain the still decreased isokinetic performance present at followup.

  • 135.
    Eriksson, Frida
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Sports Medicine.
    Test-retest reliabilitet av TrainiTest i hängande marklyft2012Independent thesis Advanced level (degree of Master (One Year)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Trainitest is a training- and testingsystem that is driven by an electric motor instead of a traditional weight stack. Trainitest measures peak, average power (watt), peak, average force (newton) and peak and average speed (mm/s). An important part of research is that the test that is performed is reliable and valid. Reliability should be tested first because the testing device will never be considered valid if it isn’t reliable. The purpose of this study is to investigate test-retest reliability of TrainiTest measuring parameters power, force and speed in the concentric and eccentric phase. The study included seven participants, all elite active athletes including one drop out after the first test which resulted in a final number of 6 participants (n = 6). The participants were active at the elite level and each participant was tested on two occasions at the same time of day at weekly intervals between test 1 and test 2. In the test the participants performed three repetitions in a sequence at four different loads and at two different speeds, 4.0m/s and 0.5m/s. After each load the participants rested for three minutes. The results of the study showed in general no reliability either at current peak values or average values under different loads and speeds, in the concentric or eccentric phase. The conclusion is that the results of the study are not directly applicable to Trainitest when its software has been updated and new versions have come out since the study ended. More studies should be done to examine TrainiTest and until then should it primarily be used as a training device.

  • 136.
    Eriksson, Hanna
    et al.
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Sports Medicine.
    Sjöstedt, Anna
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Sports Medicine.
    Jämförelse mellan operativ och konservativ behandling av ACL-ruptur hos idrottare2012Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
  • 137.
    Eriksson, Malin
    et al.
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Sports Medicine.
    Jonsson, Sandra
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Sports Medicine.
    Yoga som rehabiliteringsmetod vid fysisk aktivitet på recept mot utmattningssyndrom2012Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Prescription of physical activity on recipe in a rehabilitating purpose (FaR®) in Sweden has gone through some major development lately. Healthcare people do often recommend their patients to either try running, walking or exercising at the gym. To provide physical activity in healthcare is a way of treating the physical and emotional critical conditions caused by a stressful society. A way of living that also results in stress-related diagnoses such as the “burnout”-syndrome (characterized by the symptoms anxiety, depression and stress). Recent studies show that yoga practicing generates a wide variety of positive effects and that it has many beneficial impacts for the human body. Today healthcare doesn’t seem to embrace yoga therapy as a working method for better Public Health. The main idea in this study was to examine whether yoga can be a potential method for successful treatment of illnesses caused by a psychosocial demanding lifestyle, and to later compare these results with the existing FaR®-methods, when dealing with the “burnout” condition. This study focuses on adults, and was designed to reveal both positive and negative psychophysiological effects of yoga. Findings indicate that yoga therapy can work as a complement to the existing FaR®-treatments. In some cases yoga can also be used as single treatment, but this area needs further research. Yoga should therefore get more attention in healthcare regarding prescription of physical activity but this area also needs further research in order to establish conclusions.

  • 138.
    Ermling, Jenny
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Sports Medicine.
    Correlation Between 9+ Screening Battery Result and Injuries in Elite Floorball Players2014Independent thesis Advanced level (degree of Master (One Year)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

     

  • 139.
    Fahlman, Catalina
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Sports Medicine.
    Can A Nine Month  Training Program Prevent Anterior Cruciate Ligament Injuries?: A Study on Adolescent Alpine Skiers2012Independent thesis Advanced level (degree of Master (One Year)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    AbstractBackground. Anterior Cruciate Ligament (ACL) injuries can have an influence on the rest of the person’slife, with difficulties to participate in sports or limit the choice of work and leisure activities. Earlier studieshave successfully decreased ACL injuries with strength training in different sports, however no study havebeen made on competitive alpine ski racers. The purpose of the study is to see if a nine month strengthtraining program for the lower extremities and core can increase strength and prevent ACL injuries inadolescents who compete in alpine skiing. Method. Twelve adolescents (mean age 13,1) trained a specialdesigned training program for nine months, twice a week, to improve strength and control in the lowerextremities and core. Eight adolescents (mean age 14,1) functioned as a control group (CG) and trainednormal during the intervention time. Both groups performed the baseline- and end point test in April 2011 andApril 2012. Result. Significant results were found in the training group, especially hamstring left and right(mean diff. 36,9sec P= 0,025 resp. 26,0sec P=0,021). The CG reported three knee injuries, while the TG none.Conclusion. Significant results are limited; however, the TG increased strength significant in the hamstrings,which is an important factor in preventing ACL injuries. Additionally, the CG had three knee injuries duringthe intervention while the TG had none, also suggesting that the training program was successful.

  • 140.
    Fahlström, M
    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.
    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)
  • 141.
    Fahlström, Martin
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Sports Medicine.
    Badminton and the Achilles tendon2001Doctoral thesis, comprehensive summary (Other academic)
  • 142.
    Fahlström, Martin
    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.
    Alfredson, Håkan
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Sports Medicine.
    Ultrasound and Doppler findings in the Achilles tendon among middle-aged recreational floor-ball players in direct relation to a match.2010In: British Journal of Sports Medicine, ISSN 0306-3674, E-ISSN 1473-0480, Vol. 44, no 2, p. 140-143Article in journal (Refereed)
    Abstract [en]

    OBJECTIVE: In this study, structure, blood flow and thickness in the Achilles tendon related to tendon-loading activity were investigated. DESIGN: Examination by ultrasound (US) and colour Doppler (CD) immediately before and after 1 h of floor-ball matchplay. SETTING: Sports Medicine Unit, Umeå University, Sweden. PARTICIPANTS: 36 Achilles tendons in 18 middle-aged (mean 39 years) recreational male floor-ball players. MAIN OUTCOME MEASUREMENTS: Structure and high blood flow (HBF)/neovessels (NV) in the tendons were registered. Tendon thickness was measured 3 and 4.5 cm above the upper calcaneus and at the thickest part of the tendon. RESULTS: The US examination showed that 11/36 tendons (30.5%) in nine individuals had structural changes before and after the floor-ball match. In 7/36 tendons (five with structural changes), there were HBF/NV before, and after, the match. In six of these seven tendons, the blood flow was higher after than before the match. In three more tendons (two with structural changes), there were HBF/NV after, but not before, the match. After the match, mean tendon thickness had decreased significantly in both normal tendons and tendons with structural changes at the 3-cm level (6.0 (1.0) mm to 5.8 (0.9) mm; p<0.019), at the 4.5-cm level (5.7 (1.1) mm to 5.5 (1.0) mm; p<0.044), and at the thickest part (6.6 (1.1) mm to 6.3 (1.2) mm; p<0.000). CONCLUSIONS: In about 1/3 of the tendons, there were structural changes, about half of those tendons also had HBF/NV, which was higher after, than before, the match. Mean tendon thickness in both normal tendons and tendons with structural changes had decreased significantly after a 1-h floor-ball match.

  • 143.
    Fahlström, Martin
    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.
    Björnstig, Ulf
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Surgery.
    Lorentzon, Ronny
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Sports Medicine.
    Acute Achilles tendon rupture in badminton players1998In: American Journal of Sports Medicine, ISSN 0363-5465, E-ISSN 1552-3365, Vol. 26, no 3, p. 467-470Article in journal (Refereed)
    Abstract [en]

    All patients with badminton-related acute Achilles tendon ruptures registered during 1990 to 1994 at the University Hospital of Umeå were retrospectively followed up using a questionnaire. Thirty-one patients (mean age, 36.0 years), 27 men and 4 women, were included. Thirty patients (97%) described themselves as recreational players or beginners. The majority of the injuries (29 of 31, 94%) happened at the middle or end of the planned game. Previous local symptoms had been noticed by five patients (16%). Long-term results showed that patients treated with surgery had a significantly shorter sick leave absence than patients treated without surgery (50 versus 75 days). There was no obvious selection favoring any treatment modality. None of the surgically treated patients had reruptures, but two reruptures occurred in the nonsurgically treated group. There seemed to be fewer remaining symptoms and a higher sports activity level after the injury in the surgically treated group. Our results indicate that local muscle fatigue may interfere with strength and coordination. Preventive measures such as specific treatment of minor injuries and adequate training of strength, endurance, and coordination are important. Our findings also indicate that surgical treatment and careful postoperative rehabilitation is of great importance among badminton players of any age or sports level with Achilles tendon rupture.

  • 144.
    Fahlström, Martin
    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.
    Björnstig, Ulf
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Surgery.
    Lorentzon, Ronny
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Sports Medicine.
    Acute badminton injuries1998In: Scandinavian Journal of Medicine and Science in Sports, ISSN 0905-7188, E-ISSN 1600-0838, Vol. 8, no 3, p. 145-148Article in journal (Refereed)
    Abstract [en]

    During 1990-1994, 1.2% of all sports injuries that required emergency care at the University Hospital of Umeå were caused by badminton. In 90.7% of the cases the patients described themselves as recreational players or beginners. There were 51.3% minor injuries (AIS 1) and 48.7% moderate injuries (AIS 2). The lower extremities were affected in 92.3% of the cases. Achilles tendon ruptures (34.6%) and ankle sprains and fractures (29.5%) were the most frequent. By the time of the follow-up (10-69 months), 52.6% of the players still had symptoms from the injuries and 39.5% had not been able to return to playing badminton. Our data indicate the importance of adequate treatment and rehabilitation after acute badminton injuries.

  • 145.
    Fahlström, Martin
    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.
    Jonsson, Per
    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.
    Chronic Achilles tendon pain treated with eccentric calf-muscle training2003In: Knee Surgery, Sports Traumatology, Arthroscopy, ISSN 0942-2056, E-ISSN 1433-7347, Vol. 11, no 5, p. 327-333Article in journal (Refereed)
    Abstract [en]

    Injuries involving the Achilles tendon and manifested as chronic tendon pain are common, especially among recreational athletes. In a pilot study on a small group of patients with chronic painful midportion Achilles tendinosis, eccentric calf-muscle training was shown to give good clinical results. The aim of this prospective study was to investigate if the previously achieved good clinical results could be reproduced in a larger group of patients, and also to investigate the effects of eccentric calf-muscle training in patients with chronic insertional Achilles tendon pain. Seventy-eight consecutive patients, having chronic painful Achilles tendinosis at the mid-portion (2–6 cm level) in a total of 101 tendons (55 unilateral and 23 bilateral), and thirty consecutive patients with chronic insertional Achilles tendon pain in 31 tendons (29 unilateral and one bilateral) were treated with eccentric calf-muscle training for 12 weeks. Most patients were recreational athletes. Evaluation of the amount of tendon pain during activity was recorded on a visual analogue scale (VAS), before and after treatment. In 90 of the 101 Achilles tendons (89%) with chronic painful mid-portion Achilles tendinosis, treatment was satisfactory and the patients were back on their reinjury activity level after the 12-week training regimen. In these patients, the amount of pain during activity, registered on the VAS-scale (mean±SD), decreased ignificantly from 66.8±19.4 to 10.2±13.7. On the contrary, in only ten of the tendons (32%) with chronic insertional Achilles tendon pain was treatment satisfactory, with a significant decrease on the VAS-scale (mean±SD), from 68.3±7.0 to 13.3±13.2. Our conclusion is that treatment with eccentric calf-muscle training produced good clinical results in patients with chronic painful mid-portion Achilles tendinosis, but not in patients withchronic insertional Achilles tendon pain.

  • 146.
    Fahlström, Martin
    et al.
    Umeå University, Faculty of Medicine, Surgical and Perioperative Sciences, Sports Medicine. Umeå University, Faculty of Medicine, Community Medicine and Rehabilitation, Rehabilitation Medicine.
    Lorentzon, Ronny
    Umeå University, Faculty of Medicine, Surgical and Perioperative Sciences, Sports Medicine.
    Alfredson, Håkan
    Umeå University, Faculty of Medicine, Surgical and Perioperative Sciences, Sports Medicine.
    Painful conditions in the Achilles tendon region: a common problem in middle-aged competitive badminton players.2002In: Knee Surgery, Sports Traumatology, Arthroscopy, ISSN 0942-2056, E-ISSN 1433-7347, Vol. 10, no 1, p. 57-60Article in journal (Refereed)
    Abstract [en]

    Overuse injuries are the most frequent type in badminton, generally localized in the legs. An earlier study found 32% of young Swedish elite badminton players to have experienced disabling pain in the Achilles tendon region during the previous 5 years. The present investigation examined the prevalence and characteristics of painful conditions in the Achilles tendon region in 32 middle-aged competitive badminton players by means of questionnaire and physiotherapist's examination. Pain in the Achilles tendon region was reported by 44%, either presently or during the past 5 years, generally localized in the middle portion of the tendon. Symptoms had lasted 2 weeks-1 year (96 days). On the competition days 22% of the reported pain currently in the region. Age was found to be correlated to Achilles tendon pain, but there was no relationship between symptoms of pain and body mass index, gender, training quantity, or years of playing badminton. In conclusion, Achilles tendon pain seems to be relatively common among Swedish middle-aged competitive badminton players, particularly in the older ones.

  • 147.
    Fahlström, Martin
    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.
    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.
    Painful conditions in the Achilles tendon region in elite badminton players.2002In: American Journal of Sports Medicine, ISSN 0363-5465, E-ISSN 1552-3365, Vol. 30, no 1, p. 51-54Article in journal (Refereed)
    Abstract [en]

    The purpose of this study was to investigate the prevalence and characteristics of painful conditions in the Achilles tendon region in elite badminton players. The study group consisted of 66 players in the Swedish elite division (highest level) in badminton, 41 men (mean age, 24.4 years) and 25 women (mean age, 21.9 years). Twenty-one players (32%) reported the occurrence of a disabling painful condition in the Achilles tendon region during the previous 5 years, and 11 players (17%) had an ongoing painful condition. A majority of the painful conditions (12 of 21, or 57%) were described as involving the midportion of the Achilles tendon. The players who had a painful condition reported a significantly higher weekly training load as measured by the number of hours spent in total training, badminton training, and endurance and strength training. There were no differences in age, sex, and body mass index between the players with and without painful conditions in the Achilles tendon region.

  • 148.
    Fahlström, Martin
    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.
    Söderman, Kerstin
    Umeå University, Faculty of Medicine, Department of Community Medicine and Rehabilitation, Physiotherapy.
    Decreased shoulder function and pain common in recreational badminton players.2007In: Scand J Med Sci Sports, ISSN 0905-7188, Vol. 17, no 3, p. 246-51Article in journal (Refereed)
  • 149.
    Fahlström, Martin
    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.
    Yeap, Joo Seng
    Alfredson, Håkan
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Sports Medicine.
    Söderman, Kerstin
    Umeå University, Faculty of Medicine, Department of Community Medicine and Rehabilitation, Physiotherapy.
    Shoulder pain -- a common problem in world-class badminton players.2006In: Scandinavian journal of medicine & science in sports, ISSN 0905-7188, Vol. 16, no 3, p. 168-73Article in journal (Refereed)
  • 150.
    Ferry, Tomas
    et al.
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Orthopaedics.
    Bergström, Ulrica
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Orthopaedics.
    Hedström, Erik M
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Orthopaedics.
    Lorentzon, Ronny
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Sports Medicine.
    Zeisig, Eva
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Orthopaedics.
    Epidemiology of acute knee injuries seen at the Emergency Department at Umeå University Hospital, Sweden, during 15 years2014In: Knee Surgery, Sports Traumatology, Arthroscopy, ISSN 0942-2056, E-ISSN 1433-7347, Vol. 22, no 5, p. 1149-1155Article in journal (Refereed)
    Abstract [en]

    PURPOSE: To describe the incidence and injury distribution of knee injuries in the general population of a European setting. METHODS: Retrospective study of all knee injuries registered at the Emergency Department at Umeå University Hospital, Sweden, during 1995-2009 in relation to age, sex, diagnosis, location and activity at the time of injury, mechanism of injury, and treatment and/or follow-up plan. RESULTS: During 1995-2009, 12,663 knee injuries were registered, 8 % of all injuries. The incidence of knee injuries resulting in a visit to the Emergency Department was six cases per 1,000 person years. One-third of all injuries occurred during sports. And 30 % were 15-24 years. More men than women were injured during sporting activities and women were mostly injured during transportation. CONCLUSION: Knee injuries in a general population are common and the injury distribution varies with age and sex. Sports activities and young age were prominent features of the injured population. LEVEL OF EVIDENCE: IV.

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