Lifelong exercise, but not short‐term high‐intensity interval training, increases GDF11, a marker of successful aging: a？preliminary investigation

Lifelong exercise is associated with regulation of skeletal mass and function, reductions in frailty, and successful aging. Yet, the influence of exercise on myostatin and myostatin‐interacting factors is relatively under examined in older males. Therefore, we investigated whether serum total myostatin, free myostatin, follistatin, and growth and differentiation factor 11 (GDF11) were altered following high‐intensity interval training (HIIT) in a group of 13 lifelong sedentary (SED; 64 [6] years) and 11 lifelong exercising (LEX; 62 [6] years) older males. SED follistatin was moderately greater than LEX pre‐HIIT (Cohen's d = 0.66), and was largely greater post‐HIIT (Cohen's d = 1.22). The HIIT‐induced increase in follistatin was large in SED (Cohen's d = 0.82) and absent in LEX (Cohen's d = 0.03). GDF11 was higher in LEX pre‐HIIT (Cohen's d = 0.49) and post‐HIIT (Cohen's d = 0.63) compared to SED. HIIT resulted in no change to GDF11 in LEX or SED (Cohen's d = 0.00–0.03). Peak power output and GDF11 were correlated (r = 0.603), independent of grouping. Differences in GDF11 with lifelong exercise training, paired with the correlation between GDF11 and peak power output, suggested that GDF11 may be a relevant myostatin‐interacting peptide to successful aging in humans, and strategies to maintain this need to be further explored