When the mode of contraction of the cat papillary muscle is changed abruptly from isotonic to isometric, the tension of the first isometric contraction is as much as 22% greater and lasts substantially longer than the subsequent stable isometric contractions attained after a few beats. This previously undescribed phenomenon is largely independent of preload or inotropic influences, but is great...

Objectives: The results of a few studies about the effects of ankle brace on muscles function during the performance of different tasks are contradictory. Moreover, the effect of brace on the co-contraction of ankle muscles is undiscovered. Therefore, the present study investigated the effect of brace usage on the ankle muscles activity and co-contraction during single-leg landing. Methods: Fi...

The purpose of the present study was to compare the mechanisms of fatigue induced by a unilateral vs a bilateral submaximal isometric knee extension. Ten physically active men completed two experimental sessions, randomly presented. They were asked to maintain an isometric knee extension force corresponding to 20% of the maximal voluntary contraction (MVC) until task failure with one leg (unila...

The aim of the present study was to examine whether or not the compliance of the gastrocnemius medialis (GM) tendon and aponeurosis is influenced by submaximal fatiguing efforts. Fourteen elderly male subjects performed isometric maximal voluntary plantarflexion contractions (MVC) on a dynamometer before and after two fatiguing protocols. The protocols consisted of: (1) submaximal concentric is...

The purpose of this study was to determine the effect of gender on changes in electromyographic (EMG) signal characteristics of the quadriceps muscles with increasing force and with fatigue. A total of fourteen healthy adults (seven men, seven women) participated in the study. Subjects had to perform isometric ramp contractions in knee extension with the force gradually increasing from 0 to 100...

Strength training is one of the most common exercises practiced in the field of physical therapy or sports training. However, limited methodology is available to evaluate its effect on the target muscle. This study aimed to test the hypothesis that surface electromyographic (EMG) data from both isometric and isotonic exercise can express changes within the muscle during a 12-week strength train...

In slowly progressive conditions, such as motor neurone disease (MND), 50-80% of motor units may be lost before weakness becomes clinically apparent. Despite this, maximal voluntary isometric contraction (MVIC) has been reported as a clinically useful, reliable, and reproducible measure for monitoring disease progression in MND. We performed a study on a group of asymptomatic subjects that show...

INTRODUCTION Anecdotal evidence suggests that ingesting small volumes of pickle juice relieves muscle cramps within 35 s of ingestion. No experimental evidence exists supporting the ingestion of pickle juice as a treatment for skeletal muscle cramps. METHODS On two different days (1 wk apart), muscle cramps were induced in the flexor hallucis brevis (FHB) of hypohydrated male subjects (approx...