Physical Activity and Telomeres in Old Age: A Longitudinal 10-Year Follow-Up Study. Author: Jantunen H1,2,3, Wasenius NS4,5, Guzzardi MA6, Iozzo P6, Kajantie E7,8,9,10, Kautiainen H5, Salonen MK7, Eriksson JG4,5,7,11,12 Affiliation: <sup>1</sup>Folkhälsan Research Center, Helsinki, Finland, hjantunen@gmail.com. <sup>2</sup>Department of General Practice and Primary Health Care and Helsinki University Hospital, University of Helsinki, Helsinki, Finland, hjantunen@gmail.com. <sup>3</sup>Department of Clinical Physiology, Skin and Allergy Hospital, Helsinki University Hospital, Helsinki, Finland, hjantunen@gmail.com. <sup>4</sup>Folkhälsan Research Center, Helsinki, Finland. <sup>5</sup>Department of General Practice and Primary Health Care and Helsinki University Hospital, University of Helsinki, Helsinki, Finland. <sup>6</sup>Institute of Clinical Physiology, National Research Council (CNR), Pisa, Italy. <sup>7</sup>Public Health Promotion Unit, National Institute for Health and Welfare, Helsinki, Finland. <sup>8</sup>PEDEGO Research Unit, MRC Oulu, Oulu University Hospital and University of Oulu, Oulu, Finland. <sup>9</sup>Department of Clinical Molecular Medicine, Norwegian University of Science and Technology, Trondheim, Norway. <sup>10</sup>Children's Hospital, Helsinki University Hospital and University of Helsinki, Helsinki, Finland. <sup>11</sup>Singapore Institute for Clinical Sciences (SICS), Agency for Science and Technology (A*STAR), Singapore, Singapore. <sup>12</sup>Obstetrics and Gynecology, Yong Loo Lin School of Medicine, National University of Singapore and National University Health System, Singapore, Singapore. Conference/Journal: Gerontology. Date published: 2020 Feb 21 Other: Volume ID: 1-8 , Special Notes: doi: 10.1159/000505603. [Epub ahead of print] , Word Count: 267 BACKGROUND: Telomeres are crucial parts of chromosomes that protect the genome. They shorten every time the cell replicates, and shorter telomeres have been associated with increasing age and with many health behaviours. There is inconclusive evidence on the association between physical activity (PA) and telomere length. OBJECTIVES: To examine how leisure-time PA (LTPA) is associated with telomere length and telomere attrition during 10 years of follow-up in elderly people. DESIGN: This study is a 10-year prospective follow-up study. METHOD: For this prospective study, we examined 1,014 subjects (mean age at baseline 60.8 years) from the Helsinki Birth Cohort Study (HBCS). Relative leukocyte telomere length (LTL) was measured with a quantitative real-time PCR and LTPA with a validated questionnaire. Multiple linear regression analyses were used to assess the association between sex-specific LTPA quartiles and LTL at baseline and change in LTL over 10 years. The analyses were adjusted for age, educational attainment, smoking, body fat percentage, oestrogen exposure in women and for follow-up time when applicable. RESULTS: At baseline, volume of LTPA was not associated with LTL in men (p = 0.66) or in women (p = 0.33). Among women, however, higher volume of LTPA at baseline was associated with greater shortening of LTL (p for linearity 0.040) during the 10-year follow-up. No association was found among men (p for linearity 0.75). CONCLUSIONS: Our findings suggest that PA has a sex-specific role in regulation of telomere length in the aging process as in our study a high volume of LTPA in elderly women, but not in men, was associated with more rapid telomere attrition. © 2020 S. Karger AG, Basel. KEYWORDS: Healthy active aging; Physical activity; Prospective study PMID: 32088715 DOI: 10.1159/000505603