V˙o 2 max is associated with ACE genotype in postmenopausal women

Abstract
Relationships have frequently been found between angiotensin-converting enzyme (ACE) genotype and various pathological and physiological cardiovascular outcomes and functions. Thus we sought to determine whether ACE genotype affected maximal O2 consumption (V˙o 2 max) and maximal exercise hemodynamics in postmenopausal women with different habitual physical activity levels. Age, body composition, and habitual physical activity levels did not differ among ACE genotype groups. However, ACE insertion/insertion (II) genotype carriers had a 6.3 ml ⋅ kg−1 ⋅ min−1higher V˙o 2 max( P < 0.05) than the ACE deletion/deletion (DD) genotype group after accounting for the effect of physical activity levels. The ACE II genotype group also had a 3.3 ml ⋅ kg−1 ⋅ min−1higher V˙o 2 max( P < 0.05) than the ACE insertion/deletion (ID) genotype group. The ACE ID group tended to have a higher V˙o 2 max than the DD genotype group, but the difference was not significant. ACE genotype accounted for 12% of the variation inV˙o 2 max among women after accounting for the effect of habitual physical activity levels. The entire difference inV˙o 2 max among ACE genotype groups was the result of differences in maximal arteriovenous O2 difference (a-vDo 2). ACE genotype accounted for 17% of the variation in maximal a-vDo 2 in these women. Maximal cardiac output index did not differ whatsoever among ACE genotype groups. Thus it appears that ACE genotype accounts for a significant portion of the interindividual differences inV˙o 2 max among these women. However, this difference is the result of genotype-dependent differences in maximal a-vDo 2 and not of maximal stroke volume and maximal cardiac output.