background: surface electromyography (semg) of muscles is a non-invasive tool that can be helpful in the assessment of muscle function and some motor control evaluations. a loss of force, known as muscle fatigue is accompanied by changes in muscle electrical activity. one of the most commonly used surface emg parameters which reflects paraspinal muscle fatigue during different tasks and positio...

Due to their high specific strength and high specific stiffness properties the use of honeycomb panels is particularly attractive in spacecraft structures. However, the harsh environment produced during the launch of a satellite can subject the honeycomb cores of these sandwich structures to severe quasi-static and dynamic loads, potentially leading to static or early fatigue failures. Knowledg...

Among the aminopyridines, 3,4-diaminopyridine (DAP) is a more effective K+ channel blocker than is 4-aminopyridine (4-AP), and, furthermore, DAP enhances neuromuscular transmission. Because 4-AP improves muscle contractility, we hypothesized that DAP would also increase force and, in addition, ameliorate fatigue and improve the neurotransmission failure component of fatigue. Rat diaphragm strip...

Medical devices, particularly endovascular stents, manufactured from superelastic Nitinol, a near-equiatomic alloy of Ni and Ti, are subjected to complex mixed-mode loading conditions in vivo, including axial tension and compression, radial compression, pulsatile, bending and torsion. Fatigue lifetime prediction methodologies for Nitinol, however, are invariably based on uniaxial loading and th...

We hypothesized that patients with chronic obstructive pulmonary disease developing contractile fatigue of the quadriceps during cycle exercise may have characteristic metabolic and muscle features that could increase their susceptibility to fatigue, thus differentiating them from those who do not develop fatigue. We examined, in 32 patients, the fiber-type proportion, enzymatic activities, and...

: During exercise, there is a progressive reduction in the ability to produce muscle force. Processes within the nervous system as well as within the muscles contribute to this fatigue. In addition to impaired function of the motor system, sensations associated with fatigue and impairment of homeostasis can contribute to the impairment of performance during exercise. This review discusses some ...

objectives: skeletal-muscular disorders affect the biomechanics of the human body, especially the lower extremity, with a negative effect on the biomechanics of exercise. the main aim of this study was to evaluate the effect of fatigue on the kinematic variables of knee joints during countermovement jumps in female students of physical education with valgus knee deformity.  methods: fifteen sub...

the effect of ferrite grain size on the fatigue and tensile properties of dual phase steels with a 0.25 volumefraction of martensite (vm) under different heat treatments was investigated. the heat treatments werehomogenized at 1200 oc along with several subsequent normalizations at 910 oc, resulting in differentmicrostructures and mechanical properties. after heat treatment, the obtained steels...

This study evaluated the prevalence of fatigue in medical students and explored the potential role of lifestyle correlates and everyday executive abilities. Students in the first three years of medical school at the VU University Medical Center Amsterdam took part in a survey study (N = 701; response rate = 67%). Fatigue symptoms were measured using the Checklist Individual Strength. The preval...

Paralyzed muscle fatigues more quickly than intact muscle. The reason for this difference is currently unknown. This work will bridge this gap in knowledge by evaluating the predictive abilities of higher-resolution closed-form mathematical models of muscle force and fatigue. Knowledge garnered from this effort will suggest possible mechanisms for the differences in fatiguability of muscle in d...