Regular Sport Activity Is Able to Reduce the Level of Genomic Damage

SIMPLE SUMMARY: Intense physical activity can induce oxidative damage to cells, tissues and genomic material. In contrast, regular but moderate exercise was found to generate lower concentrations of free radicals, as a result of a favorable adaptive response by the organism. We evaluated, with the buccal micronucleus assay, the level of genomic damage in a sample of amateur athletes engaged in different disciplines. We compared the obtained data with those of subjects who practice sports only occasionally and subjects who do not practice sport at all. The aim of the study was to evaluate whether physical activity affects background levels of genomic damage, and whether the different sports disciplines induce varying levels of impact. Furthermore, our aim was to evaluate the role of some polymorphisms of gene-encoding enzymes belonging to the different damage repair systems and metabolic genes in differentially affecting these levels of DNA damage. Athletes showed significantly lower values of micronuclei, nuclear buds and binucleated cells with respect to controls. Among athletes, Sprinters and Martial Artists showed significantly higher frequencies of micronuclei than other categories. Finally, neither sex nor genetic polymorphisms seemed to influence the levels of genomic damage, further confirming that the observed genomic damage is probably due to the nature of the sport activity. ABSTRACT: Regular physical activity is considered one of the most valid tools capable of reducing the risk of onset of many diseases in humans. However, it is known that intense physical activity can induce high levels of genomic damage, while moderate exercise can elicit a favorable adaptive response by the organism. We evaluated, by the buccal micronuclei assay, the frequencies of micronuclei, nuclear buds and binucleated cells in a sample of amateur athletes practicing different disciplines, comparing the obtained data with those of subjects who practiced sports just occasionally and subjects that did not practice sport at all. The aim was to evaluate whether physical activity affects background levels of genomic damage and whether the different sports disciplines, as well as some gene polymorphisms, differentially affect these levels. A total of 206 subjects, 125 athletes and 81 controls, were recruited. Athletes showed significantly lower values of micronuclei, nuclear buds and binucleated cells with respect to controls. Sprinters and Martial Artists displayed significantly higher frequencies of micronuclei than other categories of athletes. Finally, neither sex nor gene polymorphisms seemed to influence the levels of genomic damage, confirming that the observed genomic damage is probably due to the nature of the sport activity.