Cardiorespiratory fitness as a feature of metabolic syndrome in older men and women: the Dose-Responses to Exercise Training study (DR's EXTRA).

Abstract

We studied the associations of cardiorespiratory fitness with metabolic syndrome in older men and women, because such data are limited in representative population samples. We studied a population sample of 671 men and 676 women aged 57-79 years at baseline of a randomized controlled intervention study. We assessed maximal oxygen uptake (Vo(2max)) by respiratory gas analysis during a maximal bicycle exercise test. Vo(2max) had a strong, inverse, and graded association with the risk of having metabolic syndrome as defined by the National Cholesterol Education Program criteria. Men and women in the lowest third of Vo(2max) had 10.2- and 10.8-fold higher risks and those in the middle third had 2.9- and 4.7-fold higher risks (P < 0.001 all) of metabolic syndrome than those with the highest Vo(2max) after multivariable adjustments. Factor analysis generated a principal factor that was strongly loaded by the main components of metabolic syndrome and Vo(2max) (-0.68 in men and -0.70 in women). Low cardiorespiratory fitness is associated with metabolic syndrome in older men and women. Our findings suggest that low cardiorespiratory fitness could be considered a feature of metabolic syndrome.