Abstract
In brief: Despite claims that 100 million American adults swim, 75 million bicycle, and 35 million jog, evidence suggests that these figures do not accurately indicate how many exercise on a regular basis. This paper provides interview data on the physical-activity behavior of 15,381 American adults. Projections based on the results of those interviews indicate that during 1984, approximately 77 million adults (almost 53%) participated at least once in moderate to high levels of physical activity, but only about 27 million (18.6%) were active on more than 60 days. The US Department of Health and Human Services has set a goal of having 60% of adults engaging regularly in vigorous forms of activity by 1990. These data should be helpful in providing some notion as to how close we are to this goal.