Is physical activity or aerobic power more influential on reducing cardiovascular disease risk factors?

Purpose: This study determined the relationship between aerobic power (VO₂(max)), physical activity (PA), and cardiovascular disease (CVD) risk factors. The study also determined how increased VO₂(max) and increased PA levels influence CVD risk factors of 576 low-fit adults (VO₂(max) < 30 mL · kg^-1 · min^-1). Methods: PA (Baeke questionnaire) and VO₂(max) (submaximal cycle test) of 1664 law enforcement trainees were evaluated with respect to the CVD risk factors of total cholesterol, blood pressure (BP) [BP], smoking, and obesity using separate logistic regression, adjusting for age, gender, and the other major CVD risk factors. Results: Compared with the lowest tertile of VO₂(max), the highest tertile had a reduced relative risk (RR) for elevated cholesterol RR, 0.56; CI, 0.36-0.43), BP (RR, 0.32; CI, 0.15-0.62) and obesity (RR, 0.09; CI, 0.06-0.12). The middle tertile of VO₂(max) compared with the lowest had reduced RR for elevated diastolic BP (RR, 0.44; CI, 0.23-0.66) and obesity (RR: 0.38; CI 0.28-0.50). High PA tertile, compared with low PA tertile, only had lower RR for high systolic BP (RR, 0.48; CI, 0.23-0.95). Compared with the low PA tertile, moderate or high PA had no reduction in any of the RR (P > 0.05). Participation in a 9-wk exercise program by low-fit individuals resulted in a 9% increase in PA levels (P < 0.02); however, only those subjects who increased VO₂(max) (~>3 mL · kg^-1 · min^-1 = 345) had a reduction in RR for high cholesterol (RR: 0.62; CI 0.42-0.92) and systolic BP (RR: 0.57; CI 0.40-0.80). No reduction in RR were noted for diastolic BP or obesity. Conclusions: Aerobic power appears to have more of an influence on CVD risk factors than PA levels. Further, in low-fit persons, it appears that PA resulting in an increased aerobic power is associated with a reduction in CVD risk factors of cholesterol and BP in as little as 9 wk.