The physical activity of fifth-grade students during physical education classes.

One hundred fifty-seven fifth-grade students in 20 of the 355 elementary schools in one Texas county were systematically observed during physical education classes. On average, the students spent 8.5% of class time in moderate to vigorous physical activity, 23.3% in minimal activity, and 68.1% in sedentary activity. None of the schools averaged 20% of class time in moderate to vigorous physical activity. The levels of physical activity observed are substantially lower than the levels called for in national health objectives.