Triceps surae fascicle stretch is poorly correlated with short latency stretch reflex size
Cronin, N., Rantalainen, T., & Avela, J. (2015). Triceps surae fascicle stretch is poorly correlated with short latency stretch reflex size. Muscle and Nerve, 52 (2), 245-251. doi:10.1002/mus.24538
Julkaistu sarjassaMuscle and Nerve
© 2014 Wiley Periodicals, Inc. This is a final draft version of an article whose final and definitive form has been published by Wiley. Published in this repository with the kind permission of the publisher.
Introduction: The short latency stretch reflex (SLR) is well described, but the stimulus that evokes the SLR remains elusive. One hypothesis states that reflex size is proportional to muscle fiber stretch, so this study examined the relationship between these 2 parameters in human triceps surae muscles. Methods: Achilles tendon taps and dorsiflexion stretches with different amplitudes and preactivation torques were applied to 6 participants while electromyography and muscle fascicle length changes were recorded in soleus and medial gastrocnemius (MG). Results: In response to tendon taps, neither fascicle length nor velocity changes were correlated with SLR size in either muscle, but accelerometer peaks were observed immediately after hammer-tendon contact. Similar results were obtained after dorsiflexion stretches. Discussion: Muscle fascicle stretch is poorly correlated with SLR size, regardless of perturbation parameters. We attribute the SLR trigger to the transmission of vibration through the lower limb, rather than muscle fiber stretch. ...