Oxidative stress associated with training for, and competing in an Ironman Triathlon

The benefits of regular moderate exercise in reducing cardiovascular disease are well established. However, the effect of ultra-endurance exercise remains uncertain as aerobic exercise increases the production of reactive oxygen species (ROS). ROS produce oxidative stress and molecular damage. The present study investigated markers of oxidative stress (malondialdehyde (MDA)), antioxidant status (glutathione peroxidase (GPX), catalase (CAT) and superoxide dismutase (SOD)) and arterial stiffness; in a group of athletes training for and competing in an Ironman triathlon (3.8km swim, 180km ride, 42.2km run). Resting measures were taken between three and seven days prior to the triathlon (23 male, 6 female ultra-endurance triathletes [36.6 years]; and 29 matched controls [35.3 years] active < 180 minutes. week-l). Resting samples revealed the athletes had significantly lower MDA concentration (