We studied the interrelations between, on the one hand, the physical activity (frequency, duration, intensity, and mode) measured by a questionnaire and, on the other, VO2max (submaximal bicycle ergometer test) and the explosive muscle strength (vertical jumping height). A random sample of 774 healthy subjects from the city of Turku participated in this study; the subjects were 25, 35, 45, or 55 yr of age. The VO2max of physically active 55-yr-old female subjects was on the same average level as of 25-yr-old females, who were physically inactive. Correspondingly, the average VO2max of physically active 55-yr-old male subjects was above the average level of 25-yr-old males, who were physically inactive. With the exception of the oldest female study group, the jumping test of physically active subjects gave similar results as those of their inactive counterparts who were 10 yr younger. On the basis of the sports events reported by the subjects, we classified the subjects into five activity mode categories. The mode of activity was significantly associated with VO2max in a three-way ANOVA (P = 0.0027) as well as with the jumping test result (P = 0.0001). Mixed training (includes varied types of exercise for the neuromuscular system) was the most beneficial mode of exercise for developing jumping height. The study suggests that the intensity, frequency, and duration of regular physical activity habits during leisure are associated with both VO2max and the jumping height, and that the jumping height results, in particular, are increased by mixed training.