The Effect of a Bout of Resistance Exercise on 8-Hydroxy-2 -Deoxyguanosine in Athletes and Non-Athletes

As a result of the natural metabolism in cells, free radicals and reactive species of oxygen are continuously produced and increase under physical and psychological stress conditions. Oxidative stress is a condition in which the reactive oxygen species production exceeds the antioxidant system capacity to neutralize these peroxidants. In these situations, proteins, lipids, and nucleic acids are damaged. Therefore, the purpose of this study was to determine the effects of acute resistance exercise (RE) on 8-hydroxy-2’-deoxyguanosine (8-OHdG), marker of DNA oxidation. In this quasi-experimental research, nine resistances trained (RT) and nine untrained (UT) men were randomly selected. All subjects performed a RE protocol including 4 sets of the bench press, leg press, sited bar shoulder press, arm curls and lat pull down exercises using high intensity (80% of 1RM). Blood draws occurred before and immediately after exercise and urine samples were collected before, immediately after, 3h after and 24 h after resistance exercise for the measurement of plasma lactate and urinary 8-OHdG excretion. Urinary 8-OHdG concentrations were significantly lower at post and 24h post exercise in RT compared with UT (P<0.05). The concentration of 8-OHdG was significantly elevated post, 3h post and 24h post exercise in UT as compared with pre exercise status (P<0.05). However, 8-OHdG was significantly elevated 24h post exercise in RT as compared with pre exercise status (P<0.05). The findings of the present study indicated that oxidative DNA damage was lower in bodybuilding athletes compared to the untrained. This may be due to regular resistance training status in athletes and it is possible that antioxidant capacity is improved in athletes due to performing regular resistance training.