The exercise-induced oxidative stress paradox: The effects of physical exercise training

Background : Although physical exercise training is highly recommended, phy sical exercise causes oxidative stress, which is potentially injurious, Thi s study evaluates this 'exercise paradox' by evaluating the effect of physi cal exercise on exercise-induced lipid peroxidation. Methods: Measurement of lipid peroxidation (ie, expired ethane and pentane and plasma malondealdehyde) taken during cardiopulmonary exercise stress te sting were compared between a group of 10 cardiac patients who underwent ph ysical exercise training in a cardiac rehabilitation setting and a group of 10 nonexercising cardiac patients. Results: Our findings indicate that physical exercise training increased ph ysical work capacity without a concomitant increase in expired markers of L ipid peroxidation (ethane and pentane) and decreased malondealdehyde levels , Conclusions: Because physical exercise-trained people can perform more inte nse physical work with less oxidative stress, we conclude that physical exe rcise training can reduce potential chronic health effects associated with daily activities by contributing to an overall reduction in exercise-induce d free radical production.