Physical activity and telomere length: Impact of aging and potential mechanisms of action

// Nicole C. Arsenis 1 , Tongjian You 2 , Elisa F. Ogawa 2 , Grant M. Tinsley 3 and Li Zuo 4 1 Department of Nursing, College of Nursing and Health Sciences, University of Massachusetts Boston, Boston, MA, USA 2 Department of Exercise and Health Sciences, College of Nursing and Health Sciences, University of Massachusetts Boston, Boston, MA, USA 3 Department of Kinesiology & Sport Management, Texas Tech University, Lubbock, TX, USA 4 Radiologic Sciences and Respiratory Therapy Division, School of Health and Rehabilitation Sciences, The Ohio State University College of Medicine, Columbus, OH, USA Correspondence to: Tongjian You, email: // Li Zuo, email: // Keywords : telomere(definition) length, leukocyte, muscle, physical activity, exercise Received : October 21, 2016 Accepted : March 16, 2017 Published : March 30, 2017 Abstract Telomeres protect the integrity of information-carrying DNA by serving as caps on the terminal portions of chromosomes. Telomere length decreases with aging, and this contributes to cell senescence(definition). Recent evidence supports that telomere length of leukocytes and skeletal muscle cells may be positively associated with healthy living and inversely correlated with the risk of several age-related diseases, including cancer, cardiovascular disease, obesity, diabetes, chronic pain, and stress. In observational studies, higher levels of physical activity or exercise are related to longer telomere lengths in various populations, and athletes tend to have longer telomere lengths than non-athletes. This relationship is particularly evident in older individuals, suggesting a role of physical activity in combating the typical age-induced decrements in telomere length. To date, a small number of exercise interventions have been executed to examine the potential influence of chronic exercise on telomere length, but these studies have not fully established such relationship. Several potential mechanisms through which physical activity or exercise could affect telomere length are discussed, including changes in telomerase activity, oxidative stress, inflammation, and decreased skeletal muscle satellite cell content. Future research is needed to mechanistically examine the effects of various modalities of exercise on telomere length in middle-aged and older adults, as well as in specific clinical populations.