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Exercise Leads (exercise + lead)
Selected AbstractsMitogen-activated protein kinase signal transduction in skeletal muscle: effects of exercise and muscle contractionACTA PHYSIOLOGICA, Issue 3 2001U. Widegren Exercise has numerous growth and metabolic effects in skeletal muscle, including changes in glycogen metabolism, glucose and amino acid uptake, protein synthesis and gene transcription. However, the mechanism(s) by which exercise regulates intracellular signal transduction to the transcriptional machinery in the nucleus, thus modulating gene expression, is largely unknown. This review will provide insight on potential intracellular signalling mechanisms by which muscle contraction/exercise leads to changes in gene expression. Mitogen-activated protein kinase (MAPK) cascades are associated with increased transcriptional activity. The MAPK family members can be separated into distinct parallel pathways including the extracellular signal-regulated kinase (ERK) 1/2, the stress-activated protein kinase cascades (SAPK1/JNK and SAPK2/p38) and the extracellular signal-regulated kinase 5 (ERK5). Acute exercise elicits signal transduction via MAPK cascades in direct response to muscle contraction. Thus, MAPK pathways appear to be potential physiological mechanisms involved in the exercise-induced regulation of gene expression in skeletal muscle. [source] Repeated bouts of aerobic exercise lead to reductions in skeletal muscle free radical generation and nuclear factor ,B activationTHE JOURNAL OF PHYSIOLOGY, Issue 16 2008Susan V. Brooks Chronic exercise improves endurance and skeletal muscle oxidative capacity. Despite the potential importance of reactive oxygen species (ROS) generated during exercise as regulators of these adaptations, the effect of repeated bouts of aerobic exercise on ROS generation by skeletal muscles during contractions has not been examined. Our aim was to establish the impact of repeated treadmill running exercise on muscle ROS generation and activation of redox-sensitive transcription factors. Following 8 weeks of treadmill running, mice displayed an improvement in running speed that was associated with an enhanced ability of gastrocnemius (GTN) muscles to maintain force during a protocol of isometric contractions. In contrast to GTN muscles of cage-sedentary (Sed) mice, muscles from exercised (Exer) mice did not release superoxide or nitric oxide during the isometric contractions. For male mice, basal levels of nuclear factor ,B (NF,B) and activator protein-1 (AP-1) DNA binding were increased by treadmill running, and the contraction-induced activation of NF,B and AP-1 observed in muscles of Sed mice was absent in Exer muscles. Also in contrast to Sed muscles, Exer muscles displayed no reductions in glutathione or protein thiol levels in response to contraction. Our observations of decreases for Exer compared with Sed muscles in contraction-induced (i) ROS generation, (ii) activation of redox-sensitive signalling pathways, and (iii) ROS stress suggest that exercise conditioning enhances the ability of skeletal muscle to readily and rapidly detoxify ROS and/or reduces ROS generation, providing protection from ROS-induced damage and reducing signals that might act to mediate further unnecessary adaptations. [source] Immediate blood pressure-lowering effects of aerobic exercise among patients with chronic kidney diseaseNEPHROLOGY, Issue 7 2008SAMUEL A HEADLEY SUMMARY: Aim: The current study was designed to determine the effect of moderate-intensity aerobic exercise on blood pressure responses within the laboratory for 60 min post exercise and in the subsequent 24 h period in patients with chronic kidney disease. Methods: Twenty-four subjects with stages 2,4 chronic kidney disease (age = 54.5 ± 15.2 years, body mass index = 32.0 ± 5.9 kg/m2) on antihypertensive medication completed this study. In random counterbalanced order, subjects were asked to either walk for 40 min at 50,60% VO2peak (oxygen consumption) or, on a separate day, to sit quietly in the laboratory for the same length of time. Following exercise or the non-exercise period, blood pressure was taken at 10 min intervals for 60 min. Subjects then wore an ambulatory blood pressure monitor for the next 24 h. Results: Systolic blood pressure (mmHg) was reduced by 6.5 ± 10.8 compared with the pre-exercise baseline value (130.3 ± 21.1) in the laboratory after exercise and this was greater than after the control period (0.73 ± 10.3, P < 0.05). Diastolic blood pressure (mmHg) was reduced following exercise (2.5 ± 6.4) compared with the control period (2.1 ± 4.9, P < 0.05). The mean 24 h readings did not differ between exercise or non-exercise days. Conclusion: Acute aerobic exercise leads to reduced blood pressure for at least 60 min within the laboratory in chronic kidney disease patients. [source] Hand exercise leads to modest improvement in grip and pinch strength, but no difference in hand function, pain, stiffness or dexterity in older people with hand osteoarthritisAUSTRALIAN OCCUPATIONAL THERAPY JOURNAL, Issue 1 2010Claire Ballinger No abstract is available for this article. [source] | |||||||||||||