الفهرس 
IntroductionOnly 14 pages are availabe for public view
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Abstract
As skeletal muscle represents the largest organ in the body, the influence of myokines on whole-body metabolism is potentially significant. As skeletal muscle contraction is likely the primary stimulus for myokine synthesis and secretion, it is plausible that myokines mediate, in part at least beneficial adaptations to tissues in response to exercise. Recent research has identified several hundred myokines, a large sub-population of which are specifically induced by contraction. However, the specific bioactivity of a vast number of myokines remains largely undescribed and poorly understood. Furthermore, little is known about the role of type, intensity, or frequency of contraction in regulating myokine production and release. Exercise has long been established as a central tenet to both the prevention and treatment of type 2 diabetes (T2D). Though a number of mechanisms through which exercise confers these metabolic benefits have been well characterized, the pluripotency of exercise is not yet fully understood. One such mechanism is via cross-talk between tissues stimulated by contraction and release of myokines regulating tissue function. This creates a clear link between exercise and the regulation of whole body metabolism. There have been several examples of this in recent research, most notably, the role of the contraction-induced myokine IL-6 in mediating skeletal muscle glucose uptake. These findings generated excitement as to the potential roles of contraction-induced myokines in the prevention of insulin resistance and metabolic diseases such as obesity and T2D. To date, a number of contraction-induced myokines have been identified which play a role in regulating glucose uptake, insulin sensitivity, and fat metabolism, leading factors in the development of T2D). It has become apparent that sedentary behaviour results in decreased insulin sensitivity, reduced postprandial lipid clearance, loss of muscle mass and accumulation of visceral adiposity These acute changes provide a link between physical inactivity and the increased risk of acquiring many diseases, including type 2 diabetes, cardiovascular disease, cancers such as colon and breast cancer, osteoporosis, osteoarthritis, erectile dysfunction and polycystic ovarian syndrome. The benefits of physical activity have been attributed to various mechanisms, including reduced adiposity, increased cardiorespiratory fitness, reduced circulating lipids, maintenance of muscle mass and decreased inflammation. Specifically, regular exercise is known to increase cerebral blood flow and brain oxygenation, increase adipose tissue lipolysis and reduce adipose tissue mass, allow for better heat dissipation via increased sweat rate, decrease liver fat accumulation and increase glucose uptake by skeletal muscle.