muscle metabolism


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Related to muscle metabolism: creatinine

muscle metabolism

The consumption of energy by all cells, including those of muscle tissue, to perform work. The source of chemical energy, adenosine triphosphate (ATP), is metabolized to adenosine diphosphate (ADP). If the energy requirement is short-term, the ADP is converted back to ATP. This process is too slow to keep up with energy demands during long-term exercise; thus, consumption of other fuels is required. The main sources of fuel for muscles are carbohydrates and lipids. Before being available for intracellular metabolism, glycogen is obtained when glucose is converted to glycogen. The main lipid fuel is free fatty acids present in plasma. Carbohydrates can be metabolized either in the presence of oxygen (aerobically) or in its absence (anaerobically), but lipids can be metabolized only aerobically. During light exercise or when the body is at rest, muscle metabolism is usually entirely aerobic, and the source of fuel is the free fatty acids in plasma. During intense exercise, metabolism of the fatty acids cannot keep up with the demand, and glycogen is used for energy. However, as intense exercise continues, glycogen stores are exhausted, and free fatty acids become the principal source of energy. Trained athletes have an increased ability to metabolize fatty acids as compared with sedentary people; this permits athletes to exercise longer and at higher work rates than untrained people. Athletic trainers have found that muscle glycogen stores can be increased by carbohydrate loading.
Working articulation.
See also: metabolism
References in periodicals archive ?
Schuler, "Muscle metabolism and exercise capacity in cachexia," Current Pharmaceutical Design, vol.
Muscle metabolism during exercise and heat stress in trained men: Effect of acclimation.
Ingesting the GEL may have maintained the neurological recruitment patterns of muscle during the runs, minimized muscle metabolism disruption, or delayed the change in the frequency spectra with the onset of acute fatigue (Kroll et al., 2010).
Knowledge of the metabolic adaptations to muscle metabolism induced by repeated fasting/refeeding is limited compared with the liver (Table 1), but like the liver, a greater capacity to store and spare glycogen is suggested.
However, to maximize vitamin D's effect on calcium, bone, and muscle metabolism, the 25(OH)D blood level should be above 30 ng/mL," the group wrote.
Likewise, muscle metabolism has historically been seen as a self-centered process for muscle tissue alone.
Malignant hyperthermia is caused by a genetic defect of muscle metabolism. It is a potentially fatal hypermetabolic state of skeletal muscles.
Mark Tarnopolsky, a muscle metabolism researcher and physiologist at McMaster University in Ontario.
Endurance training results in mitochondrial adaptations within skeletal muscle fibers that cause alterations in submaximal muscle metabolism. These changes in muscle metabolism yield a lower blood lactate concentration and greater utilization of fat as a fuel substrate, as well as spare muscle glycogen and reduce the disturbance of energetic homeostasis.
Arginine is also required in muscle metabolism: it is known to contribute to weight control by helping to maintain a high lean body mass and to reduce body fat.
For clinical practices, the possibility of estimating the presence of MPD by 3MEH or BU enables the physician/general practitioner to easily diagnose and monitor overtime the impact of heart failure on one important feature of muscle metabolism as well as to plan preventive measures to reduce the risk of muscle deterioration as much as possible over time.
This study sought to determine if muscle metabolism, specifically mitochondrial oxidative capacity, was related to levels of physical activity.