A 9-year longitudinal investigation into physiological aging in highly active older adults

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.