Kay, A. D., Husbands-Beasley, J. and Blazevich, A. J. (2015) Effects of contract–relax, static stretching, and isometric contractions on muscle–tendon mechanics. Medicine & Science in Sports & Exercise. 47(10), pp. 2181-2190. 0195-9131.
Kay_etal_ACSM_2015_Effects_of_contract–relax,_static_stretching,_and_isometric_contractions_on_muscle–tend ... (832kB) |
Item Type: | Article |
---|---|
Abstract: | Introduction: Loading characteristics of stretching techniques likely influence the specific mechanisms responsible for acute increases in range of motion (ROM). Therefore, the effects of a version of contract–relax (CR) proprioceptive neuromuscular facilitation stretching, static stretching (SS), and maximal isometric contraction (Iso) interventions were studied in 17 healthy human volunteers. Methods: Passive ankle moment was recorded on an isokinetic dynamometer, with EMG recording from the triceps surae, simultaneous real-time motion analysis, and ultrasound-imaging-recorded gastrocnemius medialis muscle and Achilles tendon elongation. Subjects then performed each intervention randomly on separate days before reassessment. Results: Significant increases in dorsiflexion ROM (2.5°–5.3°; P < 0.01) and reductions in whole muscle–tendon stiffness (10.1%–21.0%; P < 0.01) occurred under all conditions, with significantly greater changes detected following CR stretching (P < 0.05). Significant reductions in tendon stiffness were observed after CR stretching and Iso (17.7%–22.1%; P < 0.01) but not after SS (P > 0.05), whereas significant reductions in muscle stiffness occurred after CR stretching and SS (16.0%–20.5%; P < 0.01) but not after Iso (P > 0.05). Increases in peak passive moment (stretch tolerance) occurred after Iso (6.8%; P < 0.05), CR stretching (10.6%; P = 0.08), and SS (5.2%; P = 0.08); no difference in changes between conditions was found (P > 0.05). Significant correlations (rs = 0.69–0.82; P < 0.01) were observed between changes in peak passive moment and maximal ROM under all conditions. Conclusions: Although similar ROM increases occur after Iso and SS, changes in muscle and tendon stiffness are distinct. Concomitant reductions in muscle and tendon stiffness after CR stretching suggest a broader adaptive response that likely explains its superior efficacy in acutely increasing ROM. Although mechanical changes appear tissue-specific between interventions, similar increases in stretch tolerance after all interventions are strongly correlated with changes in ROM. |
Uncontrolled Keywords: | /dk/atira/pure/sustainabledevelopmentgoals/good_health_and_well_being |
Creators: | Kay, Anthony D, Husbands-Beasley, Jade and Blazevich, Anthony J |
Faculties, Divisions and Institutes: |
Faculties > Faculty of Health & Society > Sports, Exercise & Life Sciences Research Centres > Centre for Physical Activity and Life Sciences |
Date: | 1 October 2015 |
Date Type: | Publication |
Page Range: | pp. 2181-2190 |
Journal or Publication Title: | Medicine & Science in Sports & Exercise |
Volume: | 47 |
Number: | 10 |
Number of Pages: | 10 |
Language: | English |
DOI: | https://doi.org/10.1249/MSS.0000000000000632 |
ISSN: | 0195-9131 |
Status: | Published / Disseminated |
Refereed: | Yes |
Related URLs: | |
URI: | http://nectar.northampton.ac.uk/id/eprint/7774 |
Actions (login required)
Edit Item |