Physical activity is an important contributor to peak bone mass and bone maintenance in women. Previous research has indicated that participation in weight-bearing exercise and physical activities with high impact/ground reaction forces (GRFs) are critical to the development of peak bone mass.
PURPOSE: To determine how physical activity patterns prior to and after menarche influence bone mineral density (BMD) in college-aged women.
METHODS: The participants included 51 college-aged women (24.5 ± 0.4 years; 60.6 ±1.4 kg) currently participating in moderate to high levels of aerobic activity, both with and without participation in resistance exercise. BMD was measured at the hip, lumbar spine and whole body by DEXA (Hologic QDR 1500). Physical activity (pre-, post-menarche and current levels), menstrual history, bone health history, and calcium intake were assessed by questionnaire. Subjects were grouped by pre-menarche activity status (sedentary vs. active) and impact profiles of activities (based on GRFs) pre-menarche, post-menarche (menarche to age 20) and current. Activity group differences in BMD were determined by multiple analysis of covariance (MANCOVA) with tobacco use, alcohol use, lean body mass, age at menarche, age, and use of oral contraceptives (N=21) as the covariates.
RESULTS: The sedentary (SED) vs. active (ACT) comparisons for participation in activity prior to menarche (Pre-Men) are presented below as X ± SD. *Significantly different from SED group at the P < 0.05 level.
CONCLUSION: Women who participated in physical activity prior to menarche had higher BMD than women who were sedentary before menarche. Participation in physical activity prior to menarche appears important to the optimization of peak bone mass.