The role of oxygen-dependent substances in exercise

[摘要] This thesis investigated the role of O\(_2\)-dependent substances in mediating the vasodilatation seen following exercise (post-exercise hyperaemia) and in fatigue development. Additionally we compared young and old subjects to investigate the effects of ageing in both of these phenomena.Breathing supplementary 40% O\(_2\) during handgrip exercise at 50% of maximum voluntary contraction had no effect of the magnitude of post-exercise hyperaemia compared to air breathing control. Furthermore, aspirin administration did not alter magnitude of post-exercise hyperaemia or the levels of prostaglandin E metabolites assayed from the forearm venous efflux. Similarly the magnitude of post-exercise hyperaemia was not affected by aminophylline administration. Collectively these suggest that prostaglandins and adenosine are not obligatory mediators of post-exercise hyperaemia.Supplementary O\(_2\) breathed during recovery had no effect on fatigue in a second bout of exercise or any of the substances proposed to mediate fatigue, in young subjects. We demonstrated that older subjects showed no changes in the magnitude of post-exercise hyperaemia, but they were more fatigue resistant. There was no O\(_2\)-dependence of either post-exercise hyperaemia or fatigue in older subjects. In conclusion, we have found no evidence of O\(_2\)-dependent mediators in either post-exercise hyperaemia or fatigue.

[发布机构] University:University of Birmingham;Department:School of Clinical and Experimental Medicine

[关键词] R Medicine;R Medicine (General)