Relationships between physical activity and bone mineral content and lean mass in Mexican adolescents.

INTRODUCTION/BACKGROUND: The acquisition and maintenance of bone and lean mass health are significantly influenced by the mechanical environment of the skeleton, with physical activity emerging as an important factor. Our hypothesis proposes that high-impact physical activity improves bone mineral content and lean mass relationship in healthy adolescents depending on gender, pubertal maturity and skeletal location.

METHODOLOGY

We assessed the relation between bone mineral content, and lean mass in whole-body and limbs and leisure-time physical activity in Mexican children and adolescents. We conducted an analysis using data from the "Reference values of body composition in Mexican children and adolescents' study", which is a population-based, cross-sectional study. Using standardized protocols, Lunar iDXA instrumentation was used to measure whole-body bone mineral content and lean mass. Using a validated questionnaire, adapted for the Mexican population, the leisure-time physical activity level and the "inactive" condition were determined. ANOVA test was conducted to evaluate curve fitness and produce best-fit equations. Additionally, we used ANCOVA test to evaluate the differences between slopes and intercepts of the curves.

RESULTS

All relationships between bone mineral content and lean mass across various regions were highly significant for all Tanner stages (P < 0.001), irrespective of the type of physical activity. Examining all regions (whole-body bone mineral content vs. whole-body lean mass and lower limbs bone mineral content and lean mass, and upper limbs bone mineral content and lean mass) intercepts were significantly higher in Tanner stage 3-5 compared to Tanner stage 1-2 for both genders (P < 0.001).

CONCLUSION

These results underscore the nuanced impact of leisure-time physical activity and Tanner stage on the observed relationships, suggesting potential benefits of engaging in specific physical activities during adolescence for bone health during the later stages of puberty.