G20i Thematic Poster Session Tracking of Physical Activity
To describe the change in reported hours/week (hrs/wk) of physical activity (PA) from adolescence to young adulthood and to determine if PA during adolescence predicts PA in young adulthood.
A total of 132 males and 136 females (62% of the original cohort) comprise the sample for this analysis. Past year PA was measured by questionnaire in a population based cohort at 14, 15, 16, 17, and 24 years of age. Changes in hrs/wk of PA were examined overall; at two intensity levels, moderate (< 6 METs) and high (≥ 6 METs); and for team and individual activities.
Over the 10-year period, total PA decreased by 43% (11.7 to 6.4 hrs/wk). However, while high intensity PA decreased from a median of 5.0 to 0 hrs/wk, moderate intensity PA increased from 1.5 to 2.5 hrs/wk. Similarly, team PA decreased from 3.7 to 0 hrs/wk and individual PA increased from 2.9 to 3.1 hrs/wk. In males, the largest decline in high intensity PA and team PA occurred between ages 17 and 24 yrs. While in females, the largest decline in high intensity PA and team PA occurred between the ages 14 and 17 yrs. Multiple linear regression indicated that PA in both early and late adolescence was a significant predictor of PA in young adults for males (p < .05 for 1990 and p < .01 for 1993), but not for females (p = .13 for 1990 and p = .08 for 1993).
These data show a decrease in total PA, primarily due to decreases in high intensity and team PA, over a 10-year period from adolescence to young adulthood. These results suggest that efforts to promote PA should be targeted in early adolescence. Given the dramatic decline of time spent in team activities, schools and communities should place more emphasis on providing opportunities for adolescents to develop the skills necessary to participate in individual activities. Supported by NIAMS (AR39541) and NICHD (HD35607)