The impact of exercise on telomere length dynamics: Molecular mechanisms and implications in athletes (Review)

Telomeres are nucleotide sequences found at the ends of chromosomes and they create protective structures at chromosome ends that sustain genetic integrity, along with associated proteins known as the shelterin complex. With each cell replication round, telomeres become shortened. When telomeres become critically short, the cells lead to death, experiencing either senescence or apoptosis. The lifestyle of every individual can positively or negatively affect the pace of telomere shortening. This phenomenon of telomere shortening can be reversed through the action of telomerase. Based on the growing literature, this review discusses the molecular mechanisms underlying the positive effects of exercise on telomere length dynamics. Such positive effects of exercise on telomere length dynamics are based on reducing inflammation and oxidative stress, as well as increasing the recruitment of the shelterin protein complex in combination with enhanced telomerase activity, thereby slowing the rate of telomere shortening. In this context, athletes show telomere length elongation, due to anti‑oxidant and anti‑inflammatory response, as well as owing to high shelterin protein complex expression and telomerase action. As a result, telomere length is regarded an useful marker to monitor the cellular health and the athletic performance of athletes. Additionally, telomere analysis can offer personalized strategies for athletes to optimize their training, recovery, and injury prevention.