Are Maximal Power and Maximal Aerobic Capacity in Older and Very Old Adults Dependent on their Level of Physical Activity?

Age-related declines in maximal power (P_max) and maximal aerobic power (VO₂max) impact functional capacities. Physical activity (PA) can mitigate their decline. The present study aimed to investigate the effects of age and habitual PA level on P_max and VO₂max.

Thirty-nine young men (YM, 22.1 ± 3.4 years), 34 old men (OM, 71.7 ± 4.1 years) and 23 very old men (VOM, 85.8 ± 2.7 years) performed an incremental test to determine VO₂max and a force-velocity profile to assess P_max, maximal force (F₀) and maximal velocity (V₀). The threshold of 10,000 steps per day (SPD) was used to dichotomize participants into high-PA and low-PA groups.

Compared to YM, P_max decreased by 40% and 64% in OM and VOM, respectively, while VO₂max decreased by 29% and 51% (all p<0.001). Compared to YM, F₀ declined by 29% and 52% in OM and VOM, respectively, while V₀ decreased by 17% and 28% (all p<0.01). VO₂max, but not P_max, was greater in high-PA vs. low-PA. In VOM, SPD was related to VO₂max (r=0.79; p<0.001) and F₀ (r=0.51; p<0.05), and VO₂max was positively correlated with F₀ (r=0.72; p<0.01).

The decline in P_max, mainly mediated by the loss of force, was greater than the decrease in VO₂max. Whereas PA was associated with higher level of VO₂max, it does not appear to have an effect on P_max. The relationships between SPD, VO₂max and F₀ suggest that above 80 years, a greater strength allows to achieve a greater amount of SPD, ultimately improving VO₂max.