New records in aerobic power among octogenarian lifelong endurance athletes

Abstract

We examined whole body aerobic capacity and myocellular markers of oxidative metabolism in lifelong endurance athletes [n = 9, 81 ± 1 yr, 68 ± 3 kg, body mass index (BMI) = 23 ± 1 kg/m(2)] and age-matched, healthy, untrained men (n = 6; 82 ± 1 y, 77 ± 5 kg, BMI = 26 ± 1 kg/m(2)). The endurance athletes were cross-country skiers, including a former Olympic champion and several national/regional champions, with a history of aerobic exercise and participation in endurance events throughout their lives. Each subject performed a maximal cycle test to assess aerobic capacity (VO(2max)). Subjects had a resting vastus lateralis muscle biopsy to assess oxidative enzymes (citrate synthase and βHAD) and molecular (mRNA) targets associated with mitochondrial biogenesis [peroxisome proliferator-activated receptor-γ coactivator 1α (PGC-1α) and mitochondrial transcription factor A (Tfam)]. The octogenarian athletes had a higher (P < 0.05) absolute (2.6 ± 0.1 vs. 1.6 ± 0.1 l/min) and relative (38 ± 1 vs. 21 ± 1 ml·kg(-1)·min(-1)) VO(2max), ventilation (79 ± 3 vs. 64 ± 7 l/min), heart rate (160 ± 5 vs. 146 ± 8 beats per minute), and final workload (182 ± 4 vs. 131 ± 14 W). Skeletal muscle oxidative enzymes were 54% (citrate synthase) and 42% (βHAD) higher (P < 0.05) in the octogenarian athletes. Likewise, basal PGC-1α and Tfam mRNA were 135% and 80% greater (P < 0.05) in the octogenarian athletes. To our knowledge, the VO(2max) of the lifelong endurance athletes is the highest recorded in humans >80 yr of age and comparable to nonendurance trained men 40 years younger. The superior cardiovascular and skeletal muscle health profile of the octogenarian athletes provides a large functional reserve above the aerobic frailty threshold and is associated with lower risk for disability and mortality.

Fig. 1.

Individual V̇o_2max data from the octogenarian lifelong endurance athletes and healthy untrained octogenarians. The dotted line represents the prognostic exercise capacity [5 metabolic equivalents (METs), 17.5 ml·kg⁻¹·min⁻¹] generally necessary for an independent lifestyle and associated with an increased risk for mortality as described by Meyers et al. (41). The normative values for healthy men across the life span (n = 44,549) were originally obtained from the Cooper Institute in Dallas, TX, and have been summarized by the American College of Sports Medicine (1).

Fig. 2.

Citrate synthase and β-hydroxyacyl-CoA dehydrogenase (β-HAD) skeletal muscle enzyme activity from octogenarian lifelong endurance athletes and healthy untrained octogenarian men.

Fig. 3.

Basal peroxisome proliferator-activated receptor-γ coactivator 1α (PGC-1α) and mitochondrial transcription factor A (Tfam) mRNA levels in skeletal muscle from octogenarian lifelong endurance athletes and healthy untrained octogenarian men.