The Association Between Health-Related Fitness and After-School Physical Activity Participation

Background/Purpose: Physical inactivity and inadequate/low physical fitness are becoming prevalent among adolescents. While health-related physical fitness tests are commonly conducted in schools, it is unknown whether and to what extent the components of health-related fitness are associated with adolescent after-school physical activity. The purpose of this study was to examine the association between adolescents’ fitness and their after-school physical activity participation.

Method: Ninety seventh graders from an Eastern suburban school district participated in the study; and they ranged from 11 to 13 years old. The participants completed the health-related fitness tests including body composition (estimated by body mass index [BMI]), PACER, trunk-lift, pushup, curl-up, and sit-and-reach. Then they wore Actigraph GT3X accelerometers for seven consecutive days. The tri-axial accelerometers collected physical activity variables including light, moderate-to-vigorous physical activity (MVPA), steps, and energy expenditure during after school hours from 4:00-10:00PM. Descriptive statistics for both after-school physical activity and health-related fitness were summarized. Then, the Pearson product-moment correlation analysis was conducted to determine their association.

Analysis/Results: The adolescents’ BMI ranged from 14.06 to 29.05, with 19.1% being considered overweight, based on CDC (2000) guideline. Over 80% of the adolescents achieved the Healthy Fitness Zone for all the health-related fitness tests. The adolescents spent majority of the after-school time being sedentary (M=332.27, SD=66.89), with some light physical activity (M=83.68, SD=51.66), and low MVPA (M=11.35, SD=16.92). Their physical activity energy expenditure averaged 84.93 kcals (SD=77.95), and steps averaged 2058.52 (SD=1690.56). PACER performance (cardiorespiratory endurance) was the only fitness component correlated with after-school MVPA (r=.39), energy expenditure (r=.30), steps (r=.30), and sedentary time (r=-.23). The other test components including BMI did not significantly correlate with physical activity variables (ps>.05).

Conclusions: While the majority of the adolescents in the affluent suburban research context were relatively fit, their average MVPA was low after school. ACSM (2005) recommends a target range of 150-400 kcals energy expenditure from physical activity and/or 10,000 steps per day. Clearly, adolescents in the study cannot rely on afterschool physical activity alone to meet the recommended target. PACER performance had a low-to-moderate correlation with MVPA, a low correlation with energy expenditure and steps, and a low negative correlation with sedentary time. Despite research suggests that after-school program could positively improve adolescent fitness (Beets et al., 2009), without invention, it appears that PACER performance is the only variable associated with after-school physical activity. More studies from different contexts are needed to further understand their relation.