Activities per year
Abstract
Introduction: The muscle stretch intensity imposed during 'flexibility' training influences the magnitude of joint range of motion (ROM) adaptation. Thus, stretching whilst the muscle is voluntarily activated was hypothesized to provide a greater stimulus than passive stretching. The effect of a 6-week program of stretch imposed on an isometrically-contracting muscle (i.e. qualitatively similar to isokinetic eccentric training) on muscle-tendon mechanics was therefore studied in 13 healthy human volunteers. Methods: Before and after the training program, dorsiflexion ROM, passive joint moment, and maximal isometric plantar flexor moment were recorded on an isokinetic dynamometer. Simultaneous real-time motion analysis and ultrasound imaging recorded gastrocnemius medialis muscle and Achilles tendon elongation. Training was performed twice weekly and consisted of five sets of 12 maximal isokinetic eccentric contractions at 10[degrees][middle dot]s-1. Results: Significant increases (P<0.01) in ROM (92.7% [14.7[degrees]]), peak passive moment (i.e. stretch tolerance; 136.2%), area under the passive moment curve (i.e. energy storage; 302.6%), and maximal isometric plantar flexor moment (51.3%) were observed after training. While no change in the slope of the passive moment curve (muscle-tendon stiffness) was detected (-1.5%; P>0.05), a significant increase in tendon stiffness (31.2%; P<0.01) and decrease in passive muscle stiffness (-14.6%; P<0.05) was observed. Conclusion: The substantial positive adaptation in multiple functional and physiological variables that are cited within the primary aetiology of muscle strain injury, including strength, ROM, muscle stiffness, and maximal energy storage, indicate that the stretching of active muscle might influence injury risk in addition to muscle function. The lack of change in muscle-tendon stiffness simultaneous with significant increases in tendon stiffness and decreases in passive muscle stiffness indicates that tissue-specific effects were elicited.
Original language | English |
---|---|
Pages (from-to) | 1388-1396 |
Number of pages | 9 |
Journal | Medicine & Science in Sports & Exercise |
Volume | 48 |
Issue number | 7 |
Early online date | 30 Jan 2016 |
DOIs | |
Publication status | Published - 1 Jul 2016 |
Fingerprint
Dive into the research topics of 'Stretching of active muscle elicits chronic changes in multiple strain risk factors'. Together they form a unique fingerprint.Profiles
-
Dr Anthony Baross
- University of Northampton, Science - Associate Professor of Sport & Exercise Physiology
- Centre for Physical Activity and Life Sciences
Person: Academic
-
Prof Tony Kay
- University of Northampton, Science - Professor of Biomechanics
- Centre for Physical Activity and Life Sciences
Person: Academic
Activities
- 1 Participating in a conference or workshop
-
18th Annual Congress of the European College of Sport Science (ECSS)
Tony Kay (Participant)
28 Jun 2013 → 1 Jul 2013Activity: Organising a conference or workshop › Participating in a conference or workshop › Research