Can a client who comes to you as a sedentary individual accurately assess the intensity of the exercise you recommend? Maybe not, say the results of a recent study.

Conducted at the University of Florida, the study included data from 66 sedentary adult men and women. These subjects were asked to wear a heart rate monitor for one full day and were given a log to report their activity for that day. Then, one week later, the participants were asked to recall the amount and level of their daily activity for the previous week. This information was compared with measurements recorded by the heart rate monitors and activity logs.

In their activity logs, 47 percent
of the subjects wrote that they participated in moderate activity for at least 10 minutes, but the heart rate monitors showed that only 15 percent participated in moderate-intensity activity. Similarly, 11 percent reported in their logs experiencing a hard-intensity activity, but fewer than 2 percent actually reached that intensity according to the heart rate monitors; no participant reached a very hard intensity, but 1.5 percent of the subjects reported in their logs and in the questionnaire that they did. The postexercise questionnaire showed that 41 percent thought they had experienced a moderate-intensity activity and 3 percent felt they participated in a hard-intensity activity.

The results of this study show that sedentary adults tend to overestimate intensity of their recalled and self-reported activity, especially moderate-intensity activity. Glen E. Duncan, PhD, the principal investigator of this study, suggests that in light of these results, adults need better guidance when defining their levels of activity. This study was originally reported in Preventive Medicine (July 2001).