GREATER DECLINE IN MAXIMAL AEROBIC CAPACITY IN ENDURANCE-TRAINED VS. SEDENTARY WOMEN

Abstract

Using a cross-sectional design we previously reported that the absolute, but no the relative (%), rate of decline in maximal oxygen consumption (VO2max) with age is greater in endurance-trained compared with healthy sedentary women. We tested this hypothesis using a longitudinal approach. Eight sedentary (S; 63 ± 2 y at follow-up) and 16 endurance-trained (ET; 57 ± 2 y) women were re-evaluated after an average follow-up of 7 years. Body mass, fat-free mass, maximal respiratory exchange ratio, and maximal rating perceived exertion did not change in either group. The absoulte rate of decline in VO2max was greater (P < 0.01) in ET (−0.9 ± 0.2 ml/kg/min/y) compared with S (−0.4 ± 0.1), but the relative rates of decline were similar (−1.9 ± 0.2 vs. −1.5 ± 0.4%/y). The different rates of decline in VO2max were not associated with differences in body mass, maximal heart rate, or blood volume. In ET the absolute rate of decline in VO2max was positively associated with the changes in training volume (r = 0.55). As such, the magnitude of decline was greater (P < 0.01) in those who reduced (−1.2 ± 0.2 ml/kg/min/y; n = 10) compared with those who maintained (−0.4 ± 0.2; n = 6) training volume; the latter values were similar to S. These longitudinal data support our previous cross-sectional observations that the decrease in maximal aerobic capacity with advancing aging is greater in endurance-trained women compared with their sedentary peers due to reductions in training volume. Supported by NIH AG00847, AG13038, HL07851, and Basque Govermment AK