Fig. 2.

Mean levels of intelligence stanine scores by cardiovascular fitness or muscular strength at age 18 y. For each cognitive measure, all means significantly differed from the others, with the exception of cardiovascular fitness scores 6 vs. 7 and 8 vs. 9 in F. In B, the means of global intelligence score for muscular strength scores 4–9 were not significantly separated from each other. The SDs were 1.8–2.0 (A), 1.8–2.3 (B), and 0.8–1.3 (C–F). The P value was <0.0001 for all associations. For regression and correlation coefficients, see Table 1.