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Muscle fatigue encompasses a class of acute effects that impair motor performance. The mechanisms that can produce fatigue involve all elements of the motor system, from a failure of the formulation of the descending drive provided by suprasegmental centers to a reduction in the activity of the contractile proteins. We propose four themes that provide a basis for the systematic evaluation of th...

Muscle fatigue induced by consecutive twitches or tetani was studied in single skeletal muscle fibers of the frog, Rana japonica. The fatigue by twitch appeared sooner after the start of stimulation at lower temperatures (2-5 degrees C) than at higher ones (15-20 degrees C), while the fatigue by tetanus appeared sooner at higher temperatures. When a twitch-fatigued fiber was bathed in a solutio...

Germinario, E., A. Esposito, A. Megighian, M. Midrio, R. Betto, and D. Danieli-Betto. Effects of modulators of sarcoplasmic Ca release on the development of skeletal muscle fatigue. J Appl Physiol 96: 645–649, 2004; 10.1152/japplphysiol.00481.2003.—The reduced release of Ca from sarcoplasmic reticulum (SR) is considered a major determinant of muscle fatigue. In the present study, we investigate...

Can supraspinal/central fatigue explain the lesser muscle endurance of men compared with women? Several studies have shown that women can present with greater muscle endurance (less fatigability) compared with men (3, 5, 10, 12), although this is not always the case (4, 8). Most of these studies have focused on peripheral physiological mechanisms, mostly those within the muscle, to explain this...

BACKGROUND There are limited number of studies investigating extrapulmonary manifestations of bronchiectasis. The purpose of this study was to compare peripheral muscle function, exercise capacity, fatigue, and health status between patients with bronchiectasis and healthy subjects in order to provide documented differences in these characteristics for individuals with and without bronchiectasi...

NOS is a key enzyme in the production of NO, a molecule that directly regulates vasorelaxation and blood supply. Diverse forms of muscle disease have been clinically associated with unusual fatigue after exercise. The localization of neuronal NOS (nNOS) at the plasma membrane of muscle has recently been shown to prevent muscle fatigue after exercise. In this issue of the JCI, Lai et al. show th...

conclusions the resistance training of moderate to high intensity was well-tolerated in ms patients and may be an effective intervention for improving muscle strength, functional ability and edss-based disease severity. results two patients of group e left the program. the other eight subjects completed the program with no ms-related exacerbations/complications. there was a significant change i...