Research published in Breast Cancer Research suggests that recreational physical activity may be linked to breast tissue composition and oxidative stress levels in adolescent girls, independent of body fat percentages. The study aimed to investigate how recreational physical activity influences breast cancer risks during adolescence. The urgency of this research is noted due to the increasing incidence of breast cancer in young women and low physical activity levels among adolescents.
Study Methods
Researchers collected data from 191 Black/African-American and Hispanic girls aged 11 to 20 years from an urban cohort. Participants reported their total hours of recreational physical activity during the past week.
Breast tissue composition (water, collagen, and lipid content) was measured using optical spectroscopy. Oxidative stress was assessed through urinary concentrations of 15-F 2t -isoprostane, while inflammation markers (TNF-alpha, IL-6, and high-sensitivity C-reactive protein) were measured in blood.
Key Findings
- 51% of the girls reported no recreational physical activity in the previous week.
- 73% had not participated in any organized physical activities, and 66% had not engaged in unorganized physical activities.
- Girls who participated in at least 2 hours of organized recreational physical activities weekly showed lower breast tissue water content compared to those who did not (β = –0.41; 95% CI = –0.77 to –0.05). This association was independent of body fat percentages.
- Increased hours in organized recreational physical activities were also associated with lower urinary concentrations of 15-F 2t -isoprostane (β = –0.50; 95% CI = –0.95 to –0.05), indicating reduced oxidative stress.
- Higher markers of oxidative stress correlated with a higher percentage of collagen content in the breast (β = 0.15; 95% CI = 0.00–0.31).
- No association was found between recreational physical activity and inflammation markers, nor between inflammation markers and breast tissue composition after adjusting for percent body fat.
The study authors indicated that further longitudinal research is needed to fully understand the implications of these findings on breast cancer risk for adolescent girls.