Fig 1.

Chronic exercise adherence is associated with attenuated aging in human skin and greater mitochondrial content. (A) Stratum corneum thickness and (B) representative images of skin cross sections stained using H&E from 20- to 86-year old subjects that were highly active exercisers (ACT) or were largely sedentary (SED). Black arrow indicates the stratum corneum layer, double asterisk indicates the stratum spinosum, and single asterisk indicates the dermis. (C) Stratum spinosum layer thickness in SED and ACT subjects in various age groups. (D) Reticular dermis collagen content in each age group and (E) representative trichrome-stained cross sections of human skin. Data from SED and ACT groups have been combined as there was not a group effect. (F) mtDNA copy number in skin and (G) buccal cell samples from habitually sedentary (SED) and highly active (ACT) individuals. (H) mRNA expression of Cox7b, (I) Nd1, and (J) Pgc-1α in basal buccal cell samples from 20- to 86-year old SED and ACT subjects. Data are mean ± SE. For all analyses, n = 11–19 per age and activity group. Cross-sectional analyses and comparisons were made using a two-way anova. *indicates a significant (P < 0.05) difference from the indicated group(s). ^#indicates a significant (P < 0.05) overall activity group effect. ^†indicates a difference (P < 0.05) from 20–39 year old individuals.