Northampton Electronic Collection of Theses and Research

Range of motion, neuromechanical, and architectural adaptations to plantar flexor stretch training in humans

Blazevich, A. J., Cannavan, D., Waugh, C., Miller, S., Thorlund, S., Aagaard, P. and Kay, A. D. (2014) Range of motion, neuromechanical, and architectural adaptations to plantar flexor stretch training in humans. Journal of Applied Physiology. 117(5), pp. 452-462. 8750-7587.

Item Type: Article
Abstract: The neuromuscular adaptations in response to muscle stretch training have not been clearly described. In the present study, changes in muscle (at fascicular and whole muscle levels) and tendon mechanics, muscle activity, and spinal motoneuron excitability were examined during standardized plantar flexor stretches after 3 wk of twice daily stretch training (4 x 30 s). No changes were observed in a nonexercising control group (n = 9), however stretch training elicited a 19.9% increase in dorsiflexion range of motion (ROM) and a 28% increase in passive joint moment at end ROM (n = 12). Only a trend toward a decrease in passive plantar flexor moment during stretch (-9.9%; P = 0.15) was observed, and no changes in electromyographic amplitudes during ROM or at end ROM were detected. Decreases in Hmax:Mmax (tibial nerve stimulation) were observed at plantar flexed (gastrocnemius medialis and soleus) and neutral (soleus only) joint angles, but not with the ankle dorsiflexed. Muscle and fascicle strain increased (12 vs. 23%) along with a decrease in muscle stiffness (-18%) during stretch to a constant target joint angle. Muscle length at end ROM increased (13%) without a change in fascicle length, fascicle rotation, tendon elongation, or tendon stiffness following training. A lack of change in maximum voluntary contraction moment and rate of force development at any joint angle was taken to indicate a lack of change in series compliance of the muscle-tendon unit. Thus, increases in end ROM were underpinned by increases in maximum tolerable passive joint moment (stretch tolerance) and both muscle and fascicle elongation rather than changes in volitional muscle activation or motoneuron pool excitability.
Uncontrolled Keywords: elasticity, flexibility, muscle stiffness, stretch tolerance, tendon stiffness
Subjects: Q Science > QP Physiology > QP351 Neurophysiology and neuropsychology
Q Science > QP Physiology > QP301 Exercise and sports physiology
Creators: Blazevich, Anthony J, Cannavan, D, Waugh, C, Miller, S, Thorlund, S, Aagaard, P and Kay, Anthony D
Publisher: American Physiological Society
Northamptonshire and East Midlands: Health
Faculties, Divisions and Institutes: University Faculties, Divisions and Research Centres - OLD > Faculty of Health & Society > Sports, Exercise & Life Sciences
University Faculties, Divisions and Research Centres - OLD > Research Centre > Institute of Health and Wellbeing > Centre for Physical Activity and Chronic Disease
Faculties > Faculty of Health & Society > Sports, Exercise & Life Sciences
Research Centres > Centre for Health Sciences and Services
Research Centres > Centre for Physical Activity and Life Sciences
Date: 1 September 2014
Date Type: Publication
Page Range: pp. 452-462
Journal or Publication Title: Journal of Applied Physiology
Volume: 117
Number: 5
Language: English
DOI: https://doi.org/10.1152/japplphysiol.00204.2014
ISSN: 8750-7587
Status: Published / Disseminated
URI: http://nectar.northampton.ac.uk/id/eprint/7018

Actions (login required)

Edit Item Edit Item