The purpose of this study was to analyze whether functional ability in daily activities among 75‐year‐old men and women is predicted by physical activity, isometric muscle strength and simple function tests. In this representative sample of a general population of 405 75‐year‐olds, isometric muscle strength and functional ability in daily activities were closely related (odds ratio of disability 1.2–2.1), stressing the importance of strength in the truncus, proximal and distal muscle groups for daily activities. There were strong correlations between physical activity, isometric muscle strength as well as simple function tests and ability to manage daily activities. Those with even light physical activities at least 2–4 h a week had significantly better functional ability than those with sedentary activities. Those with heavy physical activities further improved their functiona