Fig. 2.

Linear changes in VO₂max with age for Canadians and the Tsimane. Intercepts and slopes for Canadians and Tsimane can be found in Table 4. Because age² is significant for the full sample of Tsimane females, their change in VO₂max across age is curvilinear. Slopes for endurance trained, active, and sedentary individuals from industrialized nations are drawn from a meta-analysis performed by Fitzgerald et al. (1997) for females, and Wilson and Tanaka (2000) for males. Endurance trained individuals are represented by the top dotted line above, followed by active individuals below and sedentary on the bottom. Trained individuals engage in 31 sessions of endurance exercise per week for at least a year, while active individuals engage in 2 or fewer sessions per week of cardiovascular exercise. [Color figure can be viewed in the online issue, which is available at wileyonlinelibrary.com.]