Background: The increased incidence of obesity in adolescence is a concern among medical practitioners, including physical therapists, who are involved in their care. While research on the factors linked to obesity in female adolescents is limited, there is evidence that involvement in wellness behaviors such as regular physical activity plays a role in the prevention of obesity. However, there is limited information on the frequency of activity needed to positively impact an adolescent's body mass index (BMI).
Purpose: To examine the impact of female adolescents' frequency of sports participation on body mass index (self‐reported) over time. Method: A 2x4 split‐plot ANOVA was applied as a secondary analysis to data from the National Longitudinal Study of Adolescent Health. High school students who voluntarily completed confidential questionnaires were randomly selected for this study. The study gathered information from 1,004 subjects. Students' responses to frequency of activity patterns was gathered at time 1 and body mass data was collected at time 1 and 9 to 12 months later.
Results: The interaction of the two factors (time duration and participation in sports) on BMI was not found to be significant. Sports participation was found to have a significant effect on body mass index (p=.003).
Conclusions: This study found that the frequency of weekly sports participation in adolescent females appeared to impact body mass index values. More specifically, this research showed that teens exercising 5 or more times each week had a significantly lower overall BMI than those exercising only 1 or 2 times per week. These outcomes can be useful for the physical therapist involved in exercise prescription for female adolescents.