The purpose of this study is to determine the optimal duration and intensity of exercise for elderly people for the prevention of the metabolic syndrome. RESEARCH DESIGN AND METHODS - The population-based Cooperative Research in the Region of Augsburg (KORA) S4 Survey with 1,653 participants aged 55-74 years was used to investigate the relationship between the metabolic syndrome and physical activity. RESULTS - Fifty-seven percent of men and 48% of women showed clinical symptoms of the metabolic syndrome. Leisure activities were common (>80% walked >30 min/day). Sports activities performed regularly for : <= 1 h per week reduced file odds of having the metabolic (odds ratio 0.70 [95% CI 0.49-1.02] for men and 0.74 [0.53-1.04] for women), and sports activities >2 h per week were even more effective (0.62 [0.42-0.92] for men and 0.59 [039-0.89] for women). In contrast, activities such as walking and cycling did not have an additional influence. CONCLUSIONS - Intense physical activity by the elderly should be promoted in addition to leisure physical activity for the prevention of the metabolic syndrome.