LOW LEVELS OF LEISURE-TIME PHYSICAL ACTIVITY AND CARDIORESPIRATORY FITNESS PREDICT DEVELOPMENT OF THE METABOLIC SYNDROME.

Abstract

Little is known about the association of leisure-time physical activity (LTPA) and cardiorespiratory fitness with development of the metabolic syndrome, which predisposes to diseases such as diabetes and atherosclerosis. We studied the associations of LTPA and cardiorespiratory fitness with development of the metabolic syndrome (World Health Organization [WHO] and the National Cholesterol Education Program [NCEP] definitions). A population-based cohort of 612 middle-aged men without the metabolic syndrome were followed up after 4 years. At baseline, LTPA over the previous 12 mo., maximal oxygen consumption (VO2max [ml•kg-1•min-1] and cardiovascular and metabolic risk factors were determined. At follow-up, 107 men had the metabolic syndrome (WHO definition). Men engaging in ≥ 3 h/wk of moderate or vigorous LTPA were half as likely as sedentary men to develop the metabolic syndrome after adjustment for major confounders (age, body mass index, smoking, alcohol, socioeconomic status) or potentially mediating factors (insulin, glucose, lipids, blood pressure), especially in high-risk men. Vigorous LTPA had an even stronger inverse association, particularly in unfit men. Men in the upper third of VO2max were 75% less likely than unfit men to develop the metabolic syndrome, even after adjustment for major confounders. Adjustment for possibly mediating factors attenuated the association. Associations of LTPA and VO2max with development of the metabolic syndrome as defined by the NCEP were qualitatively similar. Especially high-risk men engaging in currently recommended levels of physical activity were less likely to develop the metabolic syndrome. Cardiorespiratory fitness was also strongly protective, although possibly not independently of mediating factors.