Effects of short- and long-term physical activity on DNA stability and oxidative stress status in young soccer players

The aim of the study was to determine whether single soccer training is able to cause oxidative stress and DNA instability. We have also sought to investigate if adaptive response will be developed during 45 days training period and to what extent. This study was conducted on 16 soccer players aged 18.13±0.35 years. We used single cells gel electrophoresis (comet assay) to investigate leukocyte DNA stability. The results were presented as DNA score and percent of cells with medium and high damage. Oxidative status of our subjects was estimated through blood levels of superoxide anion, the thiobarbituric acid-reacting substances (TBARs), total antioxidant status (TAS), total oxidant status (TOS), prooxidant-antioxidant balance (PAB) and sulfhydryl-groups (SH-groups). During single soccer training, DNA score and percent of the cells with medium and high damage were increased after training but without significance. Sulphydryl-groups (P=0.033), TOS (P=0.002) and PAB (P=0.045) were significantly lower after training. After 45 days training period DNA score was decreased but with no significance. However, percent of cells with medium and high damage was significantly lower (P=0.01). TOS (P=0.001) and MDA (P=0.038) levels were also significantly lower, while sulphydryl-groups levels were significantly higher (P=0.006). This study demonstrated that single soccer training had not compromised DNA stability. Possible development of oxidative stress was effectively neutralized by very well preserved antioxidative mechanisms. It was also shown that during 45 days adaptive response was induced. All measured parameters should be considered as useful information on oxidative status of trainees.