Human length-tension curves are traditionally constructed using a model that assumes passive tension does not change during contraction (model A) even though the animal literature suggests that passive tension can decrease (model B). The study's aims were threefold: 1) measure differences in human medial gastrocnemius length-tension curves using model A vs. model B, 2) test the reliability of u...

The goal of this study was to test whether the contractile patterns of two major hindlimb extensors of guinea fowl are altered by load-carrying exercise. We hypothesized that changes in contractile pattern, specifically a decrease in muscle shortening velocity or enhanced stretch activation, would result in a reduction in locomotor energy cost relative to the load carried. We also anticipated t...

We investigated the effects of repeated eccentric exercise for rat medial gastrocnemius muscle on ankle joint stiffness and muscle connectin (titin) isoform composition (longer form, alpha-connectin; shorter form, beta-connectin). Male Wistar rats were trained on a custom-made, isokinetic dynamometer (eccentric-exercise group, n = 6; sham-operated group, n = 6). The exercise session consisted o...

Background and purpose - Many methods of gastrocnemius lengthening have been described, with different surgical challenges, outcomes, and risks to the sural nerve. Our aims were (1) to locate the gastrocnemius muscular-tendinous junction in relation to the mid-length of the fibula (from here on designated the mid-fibula), (2) to compare the dorsiflexion achieved with dorsal recession or ventral...

INTRODUCTION The extent to which gastrocnemius muscle and Achilles tendon properties contribute to the impaired walking endurance of claudicants is not known. METHODS Ultrasound images quantified muscle architecture of the lateral and medial gastrocnemius (GL and GM) and were combined with dynamometry during plantarflexor contractions to calculate tendon stress, strain, stiffness, the Young m...

introduction: effect of tripolar tens of vertebral column on slow and fast motoneurons (mns) activity of soleus muscle was previously investigated. in this study for better differentiation of the behavior of slow and fast mns, we exploited h-reflex recovery curve recording in two muscles of soleus and lateral gastrocnemius, respectively as the representatives of slow and fast muscles. methods: ...

Aim: The purpose of this study was to investigate co contraction pattern of knee flexor-extensor muscles during multidirectional destabilizing knee perturbations. Thirteen healthy men (mean ± SD; age = 24.2 ± 2.2 yr) without previous knee injury participated in the study. Surface EMG signals were recorded from seven locations distributed over the knee flexor and extensor muscles by circular AgA...

Although the body weight support treadmill training (BWSTT) in rehabilitation therapy has been appreciated for a long time, the biomechanical effects of this training on muscular system remain unclear. Ultrasonography has been suggested to be a feasible method to measure muscle morphological changes after neurological diseases such as stroke, which may help to enhance the understanding of the m...