title: Physical activity in midlife and telomere length measured in old age.
abstract: Physical activity has been associated with alterations in telomere length, a potential indicator of biological aging, but several inconsistencies exist. Our aim was to investigate the associations between physical activity in midlife and leukocyte telomere length (LTL) measured in old age in the Helsinki Businessmen Study, Finland. At entry, in 1974, 782 men (mean age 47) completed a questionnaire about their physical activity and this was collapsed into 3 categories: low (n=148), moderate (n=398) and high physical activity (n=236, 7 of whom had a competitive activity level). After 29-year follow-up in 2003, mean LTL and the proportion of short (<5 kB) telomeres were measured from DNA samples of a random subcohort of survivors (n=204, mean age 76) using the Southern blot technique. Adjusted for age, body mass index (BMI), cholesterol and smoking in 1974, the moderate physical activity group had longer mean LTL (8.27 kB, SE 0.05) than the low (8.10 kB, SE 0.07), or high (8.10 kB, SE 0.05) physical activity groups (P=0.03 between groups). Conversely, the proportion of short telomeres was lowest in the moderate physical activity group (11.35%, SE 0.25), and higher in the high (12.39%, SE 0.29), and the low physical activity (12.21%, SE 0.39) groups (P=0.02 between groups). We conclude that the results of this observational cohort study give support to the idea that both low and high physical activity is in the long-term associated with factors shortening LTL.
authors.affiliation: Oulu City Hospital, Box 77, 90015 City of Oulu, Finland. salla.savela@fimnet.fi
authors.forename: Salla
authors.initials: S
authors.lastname: Savela
authors.forename: Outi
authors.initials: O
authors.lastname: Saijonmaa
authors.forename: Timo E
authors.initials: TE
authors.lastname: Strandberg
authors.forename: Pentti
authors.initials: P
authors.lastname: Koistinen
authors.forename: Arto Y
authors.initials: AY
authors.lastname: Strandberg
authors.forename: Reijo S
authors.initials: RS
authors.lastname: Tilvis
authors.forename: Kaisu H
authors.initials: KH
authors.lastname: Pitkälä
authors.forename: Tatu A
authors.initials: TA
authors.lastname: Miettinen
authors.forename: Frej
authors.initials: F
authors.lastname: Fyhrquist
mesh_terms: D000328:Adult; D000375:Aging / Q000235:genetics* / Q000502:physiology; D015139:Blotting, Southern; D005500:Follow-Up Studies; D006801:Humans; D007962:Leukocytes / Q000648:ultrastructure; D008297:Male; D008875:Middle Aged; D009043:Motor Activity / Q000235:genetics* / Q000502:physiology; D059505:Telomere Homeostasis / Q000502:physiology*; D059506:Telomere Shortening / Q000502:physiology