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Hedlund, Mattias
Publications (9 of 9) Show all publications
Hedlund, M., Lindelöf, N., Johansson, B., Boraxbekk, C.-J. & Rosendahl, E. (2019). Development and Feasibility of a Regulated, Supramaximal High-Intensity Training Program Adapted for Older Individuals. Frontiers in Physiology, 10, Article ID 590.
Open this publication in new window or tab >>Development and Feasibility of a Regulated, Supramaximal High-Intensity Training Program Adapted for Older Individuals
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2019 (English)In: Frontiers in Physiology, ISSN 1664-042X, E-ISSN 1664-042X, Vol. 10, article id 590Article in journal (Refereed) Published
Abstract [en]

Background: High-intensity training (HIT) with extremely short intervals (designated here as supramaximal HIT) is a time-efficient training method for health and performance. However, a protocol for regulation and control of intensity is missing, impeding implementation in various groups, such as older individuals.

Methods: This study presents the development and characteristics of a novel training protocol with regulated and controlled supramaximal intervals adapted for older people. Using both quantitative and qualitative analyses, we explored the feasibility of the program, performed in a group training setting, with physically active older individuals (aged 65–75, n = 7; five women). The developed supramaximal HIT program consisted of 10 × 6 s cycle sprint intervals with ∼1 min of active recovery with the following key characteristics: (1) an individual target power output was reached and maintained during all intervals and regulated and expressed as the percentage of the estimated maximum mean power output for the duration of the interval (i.e., 6 s); (2) pedaling cadence was standardized for all participants, while resistance was individualized; and (3) the protocol enabled controlled and systematic adjustments of training intensity following standardized escalation criteria.

Aim: Our aim was to test the feasibility of a novel training regimen with regulated and controlled supramaximal HIT, adapted for older people. The feasibility criteria for the program were to support participants in reaching a supramaximal intensity (i.e., power output > 100% of estimated VO2 max), avoid inducing a negative affective response, and have participants perceive it as feasible and acceptable.

Results: All feasibility criteria were met. The standardized escalation procedure provided safe escalation of training load up to a supramaximal intensity (around three times the power output at estimated VO2 max). The participants never reported negative affective responses, and they perceived the program as fun and feasible.

Conclusion: This novel program offers a usable methodology for further studies on supramaximal HIT among older individuals with different levels of physical capacity. Future research should explore the effects of the program in various populations of older people and their experiences and long-term adherence compared with other forms of training.

Place, publisher, year, edition, pages
Frontiers Media S.A., 2019
Keywords
sprint interval training, high-intensity interval training, affective state, perceived exertion, training intensity, aging
National Category
Sport and Fitness Sciences
Identifiers
urn:nbn:se:umu:diva-159855 (URN)10.3389/fphys.2019.00590 (DOI)000468572300001 ()
Available from: 2019-06-10 Created: 2019-06-10 Last updated: 2020-05-14Bibliographically approved
Granström, F., Hedlund, M., Lindström, B. & Eriksson, S. (2019). Test-retest reliability of the twenty-five-hole peg test in patients who had a stroke. BMJ Open, 9(12), Article ID e032560.
Open this publication in new window or tab >>Test-retest reliability of the twenty-five-hole peg test in patients who had a stroke
2019 (English)In: BMJ Open, ISSN 2044-6055, E-ISSN 2044-6055, Vol. 9, no 12, article id e032560Article in journal (Refereed) Published
Abstract [en]

Objectives: Weaknesses of the nine-hole peg test include high floor effects and a result that might be difficult to interpret. In the twenty-five-hole peg test (TFHPT), the larger number of available pegs allows for the straightforward counting of the number of pegs inserted as the result. The TFHPT provides a comprehensible result and low floor effects. The objective was to assess the test-retest reliability of the TFHPT when testing persons with stroke. A particular focus was placed on the absolute reliability, as quantified by the smallest real difference (SRD). Complementary aims were to investigate possible implications for how the TFHPT should be used and for how the SRD of the TFHPT performance should be expressed.

Design: This study employed a test-retest design including three trials. The pause between trials was approximately 10-120 s.

Participants, setting and outcome measure: Thirty-one participants who had suffered a stroke were recruited from a group designated for constraint-induced movement therapy at outpatient clinics. The TFHPT result was expressed as the number of pegs inserted.

Methods: Absolute reliability was quantified by the SRD, including random and systematic error for a single trial, SRD2.1, and for an average of three trials, SRD2.3. For the SRD measures, the corresponding SRD percentage (SRD%) measure was also reported.

Results: The differences in the number of pegs necessary to detect a change in the TFHPT for SRD2.1 and SRD2.3 were 4.0 and 2.3, respectively. The corresponding SRD% values for SRD2.1 and SRD2.3 were 36.5% and 21.3%, respectively.

Conclusions: The smallest change that can be detected in the TFHPT should be just above two pegs for a test procedure including an average of three trials. The use of an average of three trials compared with a single trial substantially reduces the measurement error.

Place, publisher, year, edition, pages
BMJ Publishing Group Ltd, 2019
National Category
Other Medical Sciences
Identifiers
urn:nbn:se:umu:diva-168799 (URN)10.1136/bmjopen-2019-032560 (DOI)000512773400180 ()31831545 (PubMedID)
Available from: 2020-03-10 Created: 2020-03-10 Last updated: 2020-03-10Bibliographically approved
Tronarp, R., Nyberg, A., Hedlund, M., Häger, C., McDonough, S. & Björklund, M. (2018). Office-cycling: a promising way to raise pain thresholds and increase metabolism with minimal compromising of work performance. BioMed Research International, Article ID 5427201.
Open this publication in new window or tab >>Office-cycling: a promising way to raise pain thresholds and increase metabolism with minimal compromising of work performance
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2018 (English)In: BioMed Research International, ISSN 2314-6133, E-ISSN 2314-6141, article id 5427201Article in journal (Refereed) Published
Abstract [en]

Aim: Establishing the effects of low intensity cycling (LC), moderate intensity cycling (MC), and standing at a simulated office workstation on pain modulation, work performance, and metabolic expenditure.

Methods: 36 healthy adults (21 females), mean age 26.8 (SD 7.6) years, partook in this randomized 3 x 3 crossover trial with 75 minutes of LC on 20% of maximum aerobic power (MAP) output, 30 minutes of MC on 50% of MAP, and standing 30 minutes with 48-hour wash-out periods. Outcome measures were pain modulation (pressure pain threshold (PPT) and thermal pain threshold)), work performance (transcription, mouse pointing, and cognitive performance), and metabolic expenditure.

Results: PPTs increased in all conditions. PPT trapezius showed the highest increase after LC, 39.3 kilopascals (kPa) (15.6; 78.6), compared to MC, 17.0 kPa (2.8; 49.9), and standing, 16.8 kPa (-5.6; 39.4),p = 0.015. Transcription was reduced during LC and MC. Mouse pointing precision was best during standing and worst and slowest during MC. Cognitive performance did not differ between conditions. Metabolic expenditure rates were 1.4 (1.3; 1.7), 3.3 (2.3; 3.7), and 7.5 (5.8; 8.7) kcal/minute during standing, LC, and MC, respectively (p < 0.001).

Conclusions: LC seems to be the preferred option; it raised PPTs, more than doubled metabolic expenditure, whilst minimally influencing work performance.

Place, publisher, year, edition, pages
Hindawi Publishing Corporation, 2018
National Category
Physiotherapy Occupational Health and Environmental Health
Identifiers
urn:nbn:se:umu:diva-143414 (URN)10.1155/2018/5427201 (DOI)000423319500001 ()
Available from: 2017-12-22 Created: 2017-12-22 Last updated: 2018-06-09Bibliographically approved
Hedlund, M., Lindström, B., Sojka, P., Lundström, R. & Boraxbekk, C.-J. (2016). Is better preservation of eccentric strength after stroke due to altered prefrontal function?. Neurocase, 22(2), 229-242
Open this publication in new window or tab >>Is better preservation of eccentric strength after stroke due to altered prefrontal function?
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2016 (English)In: Neurocase, ISSN 1355-4794, E-ISSN 1465-3656, Vol. 22, no 2, p. 229-242Article in journal (Refereed) Published
Abstract [en]

Ventrolateral prefrontal cortex (VLPFC) is part of a network that exerts inhibitory control over the motor cortex (MC). Recently, we demonstrated that VLPFC was more activated during imagined maximum eccentric than during imagined concentric contractions in healthy participants. This was accompanied with lower activation levels within motor regions during imagined eccentric contractions. The aim was to test a novel hypothesis of an involvement of VLPFC in contraction mode-specific modulation of force. Functional magnetic resonance imaging was used to examine differences in VLPFC and motor regions during the concentric and the eccentric phases of imagined maximum contractions in a selected sample of subjects with stroke (n = 4). The subjects were included as they exhibited disturbed modulation of force. The previously demonstrated pattern within VLPFC was evident only on the contralesional hemisphere. On the ipsilesional hemisphere, the recruitment in VLPFC was similar for both modes of contractions. The findings support a hypothesis of the involvement of VLPFC in contraction mode-specific modulation of maximum force production. A disturbance of this system might underlie the lack of contraction mode-specific modulation commonly found among stroke subjects, often expressed as an increased ratio between eccentric and concentric strength.

Keywords
Motor imagery, fMRI, stroke, eccentric, concentric, inhibition
National Category
Neurosciences
Identifiers
urn:nbn:se:umu:diva-55461 (URN)10.1080/13554794.2015.1130232 (DOI)000369770400016 ()26750576 (PubMedID)
Note

Originally included in thesis in manuscript form.

Available from: 2012-05-16 Created: 2012-05-15 Last updated: 2018-06-08Bibliographically approved
Nyberg, A., Hedlund, M., Kolberg, A., Alm, L., Lindström, B. & Wadell, K. (2014). The accuracy of using elastic resistance bands to evaluate muscular strength. Advances in Physiotherapy, 16(2), 104-112
Open this publication in new window or tab >>The accuracy of using elastic resistance bands to evaluate muscular strength
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2014 (English)In: Advances in Physiotherapy, ISSN 1403-8196, E-ISSN 1651-1948, European Journal of Physiotherapy, Vol. 16, no 2, p. 104-112Article in journal (Refereed) Published
Abstract [en]

Elastic resistance as a tool for evaluation of muscular strength has rarely been addressed even though it is commonly used in exercise and rehabilitation regimens involving the shoulder muscles. The aim was therefore to investigate the relationship and potential difference between development of force during maximal isokinetic (maximum peak force, maximum mean force and peak mean force) and elastic (one-repetition maximum (1 RM)) concentric shoulder fl exion in healthy older adults. A total of 30 voluntary adults over the age of 50 (15 women, 15 men) were included. Intraclass correlation coefficient absolute agreement was 0.85, 0.43 and 0.48 for the isokinetic values respectively, when all subjects were analysed together. No difference was found between the isokinetic maximum peak force value and the elastic 1 RM for all participants (0.15 kg, p 0.791), for men (0.80 kg, p 0.121) or women ( 0.49 kg, p 0.135). Variations at an individual level, i.e. 95% limits of agreement, were 3.3 kg for all participants, 2.8 kg for women and 3.2 kg for men. These results imply that elastic resistance could be used to evaluate shoulder fl exion strength in both older men and women. However, thevariation on an individual level and the lower agreement among women is important to consider.

Place, publisher, year, edition, pages
Informa Healthcare, 2014
National Category
Physiotherapy
Identifiers
urn:nbn:se:umu:diva-87826 (URN)10.3109/21679169.2014.889746 (DOI)
Available from: 2014-04-13 Created: 2014-04-11 Last updated: 2018-06-08Bibliographically approved
Hedlund, M. (2012). Biomechanical and neural aspects of eccentric and concentric muscle performance in stroke subjects: Implications for resistance training. (Doctoral dissertation). Umeå: Umeå universitet
Open this publication in new window or tab >>Biomechanical and neural aspects of eccentric and concentric muscle performance in stroke subjects: Implications for resistance training
2012 (English)Doctoral thesis, comprehensive summary (Other academic)
Abstract [en]

Muscle weakness is one of the major causes of post-stroke disability. Stroke rehabilitation programs now often incorporate the same type of resistance training that is used for healthy subjects; however, the training effects induced from these training strategies are often limited for stroke patients. An important resistance training principle is that an optimal level of stress is exerted on the neuromuscular system, both during concentric (shortening) and eccentric (lengthening) contractions. One potential problem for post-stroke patients might be difficulties achieving sufficient levels of stress on the neuromuscular system. This problem may be associated with altered muscular function after stroke. In healthy subjects, maximum strength during eccentric contractions is higher than during concentric contractions. In individuals with stroke, this difference in strength is often increased. Moreover, it has also been shown that individuals with stroke exhibit alteration with respect to how the strength varies throughout the range of motion. For example, healthy subjects exhibit a joint specific torque-angle relationship that normally is the same irrespective of contraction mode and contraction velocity. In contrast, individuals with stroke exhibit an overall change of the torque-angle relationship. This change, as described in the literature, consists of a more pronounced strength loss at short muscle length. In individuals with stroke, torque-angle relationships are only partially investigated and so far these relationships have not been analysed using testing protocols that include eccentric, isometric, and concentric modes of contraction.

 

This thesis investigates the torque-angle relationship of elbow flexors in subjects with stroke during all three modes of contractions – isometric, concentric, and eccentric ­– and the relative loading throughout the range of movement during a resistance exercise. In addition, this thesis studies possible central nervous system mechanisms involved in the control of muscle activation during eccentric and concentric contractions.

 

The torque-angle relationship during maximum voluntary elbow flexion was examined in stroke subjects (n=11), age-matched healthy subjects (n=11), and young subjects (n=11) during different contraction modes and velocities. In stroke subjects, maximum torque as well as the torque angle relationship was better preserved during eccentric contractions compared to concentric contractions. Furthermore, the relative loading during a resistance exercise at an intensity of 10RM (repetition maximum) was examined. Relative loading throughout the concentric phase of the resistance exercise, expressed as percentage of concentric torque, was found to be similar in all groups. However, relative loading during the eccentric contraction phase, expressed as the percentage of eccentric isokinetic torque, was significantly lower for the stroke group. In addition, when related to isometric maximum voluntary contraction, the loading for the stroke group was significantly lower than for the control groups during both the concentric and eccentric contraction phases.

Functional magnetic resonance imaging was used to examine differences between recruited brain regions during the concentric and the eccentric phase of imagined maximum resistance exercise of the elbow flexors (motor imagery) in young healthy subjects (n=18) and in a selected sample of individuals with stroke (n=4). The motor and premotor cortex was less activated during imagined maximum eccentric contractions compared to imagined maximum concentric contraction of elbow flexors. Moreover, BA44 in the ventrolateral prefrontal cortex, a brain area that has been shown to be involved in inhibitory control of motor activity, was additionally recruited during eccentric compared to concentric conditions. This pattern was evident only on the contralesional (the intact hemisphere) in some of the stroke subjects. On the ipsilesional hemisphere, the recruitment in ventrolateral prefrontal cortex was similar for both modes of contractions. 

 

Compared to healthy subjects, the stroke subjects exhibited altered muscular function comprising a specific reduction of torque producing capacity and deviant torque-angle relationship during concentric contractions. Therefore, the relative training load during the resistance exercise at a training intensity of 10RM was lower for subjects with stroke. Furthermore, neuroimaging data indicates that the ventrolateral prefrontal cortex may be involved in a mechanism that modulates cortical motor drive differently depending on mode of the contractions. This might partly be responsible for why it is impossible to fully activate a muscle during eccentric contractions. Moreover, among individuals with stroke, a disturbance of this system could also lie behind the lack of contraction mode-specific modulation of muscle activation that has been found in this population. The altered neuromuscular function evident after a stroke means that stroke victims may find it difficult to supply a sufficient level of stress during traditional resistance exercises to promote adaptation by the neuromuscular system. This insufficiency may partially explain why the increase in strength, in response to conventional resistance training, often has been found to be low among subjects with stroke.

Abstract [sv]

Muskelsvaghet är en av orsakerna till funktionshinder efter stroke. I rehabiliteringsprogram för personer som drabbats av stroke förekommer det numera att styrketräning används i syfte att öka muskelstyrkan. Effekten av styrketräning har dock ofta visat sig vara begränsad. En viktig styrketräningsprincip är att muskulaturen belastas tillräckligt nära maximal styrka under både koncentriska kontraktioner (när man lyfter en vikt) och excentriska kontraktioner (när man kontrollerat sänker en vikt). Ett potentiellt problem skulle kunna vara att personer med stroke inte belastas optimalt under träning på grund av förändrad muskelfunktion. Efter stroke är muskelfunktionen ofta förändrad såtillvida att styrkenedsättningen är mer uttalad under koncentriska kontraktioner. Därutöver har man funnit att styrkenedsättningen är mest uttalad när muskeln är i sitt mest förkortade läge. Detta fenomen har dock inte studerats för alla tre kontraktionstyper, det vill säga excentriska, koncentriska och isometriska kontraktioner, hos personer med stroke.

 

Denna avhandling undersöker sambandet mellan styrka och ledvinkel över armbågsleden hos personer med stroke under alla tre kontraktionstyper – excentrisk, koncentrisk och isometrisk, samt relativ belastning genom rörelsebanan under en styrketräningsövning. Därutöver undersöker denna avhandling också hjärnans aktiveringsmönster under excentriska och koncentriska kontraktioner.

 

Sambandet mellan styrka och ledvinkel undersöktes hos personer med stroke (n = 11), åldersmatchade (n = 11) och unga försökspersoner (n = 11). Jämfört med kontrollgrupperna var maximal styrka för personer med stroke mest nedsatt, samt även den oproportionerligt stora styrkenedsättningen vid kort muskelängd som mest uttalad, under koncentriska kontraktioner. Denna avvikelse var minst uttalad vid excentriska kontraktioner. Vidare studerades hur hög belastningen på muskulaturen var i jämförelse med muskelns maximala styrka under en styrketräningsliknande övning för armbågsflexorer vid en träningsintensitet på 10RM. Den uppmätta belastningen under den koncentriska fasen av styrketräningsövningen, uttryckt som procent av den genomsnittliga koncentriska styrkan, var densamma för alla grupperna. Under den excentriska fasen av övningen var dock belastningen, uttryckt som procent av den maximala excentriska styrkan, signifikant lägre för personer med stroke. Träningsbelastningen utgjorde också en lägre andel av den maximala isometriska styrkan för personer med stroke, både under den koncentriska och under den excentriska fasen.

 

Funktionell magnetresonanstomografi (fMRI) användes för att undersöka hjärnans aktiveringsmönster hos unga försökspersoner (n = 18) och hos individer med stroke (n = 4) när de föreställde sig att de utförde maximal styrketräning för armbågsflexorer (motor imagery). Resultatet visade att primära motorbarken och premotoriska barken var mindre aktiverade när unga friska försökspersonerna föreställde sig utföra maximala excentriska, jämfört med maximala koncentriska kontraktioner. Dessutom var en region i ventrolaterala prefrontala barken, som i tidigare studier visat sig vara inblandat i reglering och hämning av muskelaktivering, mer aktiverade under föreställda excentriska kontraktioner. Detta aktiveringsmönster i den prefrontala barken återfanns dock endast i den icke skadade hjärnhalvan hos personer med stroke.

 

Jämfört med kontrollgrupperna uppvisade försökspersonerna med stroke en förändrad muskelfunktion som bestod av en specifik nedsättning av styrkan under koncentriska kontraktioner samt också ett mer avvikande samband mellan styrka och ledvinkel under koncentriska kontraktioner. Den relativa belastningen under utförandet av en styrketräningsövning med en intensitet på 10RM var på grund av dessa avvikelser lägre för försökspersoner med stroke. Hjärnavbildnings-studierna indikerade att ventrolaterala prefrontala barken verkar vara involverat i ett kortikalt moduleringssystem som reglerar muskel-aktivering olika beroende på kontraktionstyp under maximala kontraktioner. Detta skulle kunna vara en underliggande mekanism bakom den hittills obesvarade frågan varför det är omöjligt att aktivera muskulaturen maximalt under excentriska kontraktioner. En störning av detta moduleringssystem hos personer med stroke verkar också kunna ligga bakom den förändrade regleringen av muskelaktivering som visat sig förekomma hos personer med stroke. Neuromuskulär funktion efter stroke är förändrad i flera avseenden vilket verkar medföra att muskulaturen inte belastas optimalt under konventionell styrketräning. Detta kan vara en delförklaring till varför styrkeökningen som svar på träning ofta är liten hos personer med stroke.  

Place, publisher, year, edition, pages
Umeå: Umeå universitet, 2012. p. 76
Series
Umeå University medical dissertations, ISSN 0346-6612 ; 1510
Keywords
fMRI, Isokinetic, Motor imagery, Muscular strength, Resistance training, Neurological rehabilitation
National Category
Physiotherapy
Identifiers
urn:nbn:se:umu:diva-55466 (URN)978-91-7459-446-1 (ISBN)
Public defence
2012-06-08, NUS, Vårdvetarhuset, Aulan, Umeå Universitet, Umeå, 13:00 (Swedish)
Opponent
Supervisors
Available from: 2012-05-16 Created: 2012-05-15 Last updated: 2018-06-08Bibliographically approved
Olsson, C.-J., Hedlund, M., Sojka, P., Lundström, R. & Lindström, B. (2012). Increased prefrontal activity and reduced motor cortex activity during imagined eccentric compared to concentric muscle actions. Frontiers in Human Neuroscience, 6(255)
Open this publication in new window or tab >>Increased prefrontal activity and reduced motor cortex activity during imagined eccentric compared to concentric muscle actions
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2012 (English)In: Frontiers in Human Neuroscience, ISSN 1662-5161, E-ISSN 1662-5161, Vol. 6, no 255Article in journal (Refereed) Published
Abstract [en]

In this study we used functional magnetic resonance imaging (fMRI) to examine differences in recruited brain regions during the concentric and the eccentric phase of an imagined maximum resistance training task of the elbow flexors in healthy young subjects. The results showed that during the eccentric phase, pre-frontal cortex (BA44) bilaterally was recruited when contrasted to the concentric phase. During the concentric phase, however, the motor and pre-motor cortex (BA 4/6) was recruited when contrasted to the eccentric phase. Interestingly, the brain activity of this region was reduced, when compared to the mean activity of the session, during the eccentric phase. Thus, the neural mechanisms governing imagined concentric and eccentric contractions appear to differ. We propose that the recruitment of the pre-frontal cortex is due to an increased demand of regulating force during the eccentric phase. Moreover, it is possible that the inability to fully activate a muscle during eccentric contractions may partly be explained by a reduction of activity in the motor and pre-motor cortex.

Keywords
motor imagery, fMRI, eccentric, concentric, force modulation
National Category
Neurosciences
Identifiers
urn:nbn:se:umu:diva-57988 (URN)10.3389/fnhum.2012.00255 (DOI)
Note

Originally included in M. Hedlunds thesis in manuscript form.

Available from: 2012-10-02 Created: 2012-08-22 Last updated: 2018-06-08Bibliographically approved
Hedlund, M., Sojka, P., Lundström, R. & Lindström, B. (2012). Insufficient loading in stroke subjects during conventional resistance training. Advances in Physiotherapy, 14(1), 18-28
Open this publication in new window or tab >>Insufficient loading in stroke subjects during conventional resistance training
2012 (English)In: Advances in Physiotherapy, ISSN 1403-8196, E-ISSN 1651-1948, Vol. 14, no 1, p. 18-28Article in journal (Refereed) Published
National Category
Physiotherapy
Identifiers
urn:nbn:se:umu:diva-55454 (URN)10.3109/14038196.2012.658861 (DOI)
Available from: 2012-05-15 Created: 2012-05-15 Last updated: 2018-06-08Bibliographically approved
Hedlund, M., Sojka, P., Lundström, R. & Lindström, B. (2012). Torque-angle relationship are better preserved during eccentric compared to concentric contractions in patients with stroke. Isokinetics and exercise science, 20(2), 129-140
Open this publication in new window or tab >>Torque-angle relationship are better preserved during eccentric compared to concentric contractions in patients with stroke
2012 (English)In: Isokinetics and exercise science, ISSN 0959-3020, E-ISSN 1878-5913, Vol. 20, no 2, p. 129-140Article in journal (Refereed) Published
Abstract [en]

The aim of this study was to compare the effect of isokinetic contraction mode and velocity on the torque-angle relationship during maximum voluntary elbow flexion in patients with stroke, age-matched healthy subjects and young subjects. To eliminate the effect of torque amplitude differences between subjects and groups, the torque values throughout the ROM were individually normalized to the peak value for each contraction velocity. The results show that in stroke patients the normalized torque angle relationship during the eccentric contractions was better preserved than during concentric contractions. Specifically, during eccentric contractions, stroke patients exhibited a torque-angle relationship that was closer to normal as the test velocity increased. The opposite trend could be seen in concentric contractions where the torque-angle relationship became more divergent from normal with a rise in the velocity. The torque-angle relationships were essentially the same for the control groups, irrespective of contraction mode or velocity. These findings may have significance for loading patterns of resistance training exercises used with stroke patients as such exercises normally are biomechanically designed for normal torque angle relationships. In clinical practice, these findings may partly explain why the strength increases due to resistance training are limited for patients with stroke.   

Keywords
elbow; concentric; eccentric; strength; torque-angle relationship; resistance training.
National Category
Physiology
Identifiers
urn:nbn:se:umu:diva-55465 (URN)10.3233/IES-2012-0455 (DOI)000305152100009 ()
Note
Submitted version published in dissertation had the title "Better preserved torque-angle relationship during eccentric compared to concentric contractions in patients with stroke".Available from: 2012-05-15 Created: 2012-05-15 Last updated: 2018-06-08Bibliographically approved
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