Comparison of body composition, bone mineral density and health-related physical fitness by physical activity levels in young women

Abstract

Purpose The purpose of the study was to determine difference of body composition, bone mineral density and health-related fitness by physical activity level in young women. Methods A total of 90 women aged 19-29 years participated in this study. The subjects were divided into three groups (low, middle, and high level) according to the physical activity level estimated by bone-specific physical activity questionnaire(BPAQ). Body height and weight were measured. Body composition parameters including four sites of bone mineral density(BMD) were estimated by DXA (Hologic, QDR-4500, USA). Health-related fitness tests was assessed using sit & reach, grip strength, sit-ups, and VO2max. Statistical analysis was performed using SAS version 9.4. All data were presented in terms of means and standard deviations. One-way ANOVA was applied to determine difference of dependent variables by physical activity level. Duncan's multiple range test was used as a post-hoc test. The statistical significance level was set at p < .05. Results There were significant differences on body weight(F = 4.867, p = .01), body mass index(F = 5.053, p = .008) and fat-free mass(F = 8.364, p = .0001) among the three groups. Significant differences were found on whole body BMD(F = 16.730, p = .0001), lumbar BMD(F = 11.480, p = .0001), femur BMD(F = 42.182, p = .0001) and forearm BMD(F = 5.560, p = .005) among the three groups. There were also significant differences on sit and reach(F = 11.433, p = .0001), sit-ups(F = 17.972, p = .0001), VO2max(F = 3.106, p = .05) and duration of GXT(F = 7.479, p = .001). Conclusions There were differences on body composition, bone mineral density and health-related physical fitness by physical activity levels. Nevertheless, the questionnaire used in this study was not able to judge participation in various exercise types including aerobic exercise or resistance exercise. Therefore, in the future study, longitudinal study considering various types of physical activity and dietary intake will be needed.