Abstract / Summary
Abstract This study examined the impact of nine years of continued cycling exercise on physiological function in older exercisers, viewed as a model of inherent biological aging free from the negative effects of inactivity. A range of cardiorespiratory indices were measured, with peak oxygen consumption (V̇O 2peak ) as the primary outcome. Of an original 125 cyclists first assessed in 2012–2013, 82 (53 males, 29 females) returned 9 years later (aged 64–86 years at follow up). V̇O 2peak declined by 19.7% (44.1 to 35.4 ml·kg⁻ 1 ·min⁻ 1 , P < 0.0001). Body mass remained stable, but lean tissue mass decreased (−8.1%, P < 0.0001) and body fat percentage increased from 23.8% to 29.2% ( P < 0.0001). Resting blood pressure and metabolic indices remained within normal ranges, while lung function declined. Changes were similar between males and females. Based on returning health status, participants were classified as: optimal agers (OA; no disease, n = 35), successful agers (SA; ≤ 2 well-controlled diseases, n = 24), or those with compromised health (CH; poorly controlled disease, mainly cardiovascular, n = 23). V̇O 2peak declined more in CH than OA (24.2% vs 17.3%, P < 0.05), but overall, 98.7% of those who completed the test were at or above the 90th percentile for V̇O 2peak based on reference populations. Almost all indices showed no difference between health groups over 9 years. Whilst acknowledging potential survivor bias, these longitudinal data support the concept that even with emerging disease, exercise confers good physiological function in a body that is declining with age.