Relationship between Body Composition and Health Behaviors in High and Low Fit College Women

Abstract

College-age women exhibit particular susceptibility to establishing health behaviors resulting in unwanted weight gain or chronic dieting. Understanding the relative contribution of health behaviors to body composition could inform targeted interventions to correct unhealthy weight gain or loss. PURPOSE: To create a model describing relationships among physical activity (PA), aerobic fitness (VO2max), eating behavior traits and their association with body composition in female college students. METHODS: Female students (n = 98) were recruited from a freshmen-level university nutrition class. Percentage body fat (PBF) was assessed by bioimpedance following an overnight-fast. VO2max was estimated from 1.5-mile time trial performance. Dietary energy intake (EI) was determined using 24-hour dietary recalls and PA was assessed by accelerometry. The eating behavior traits drive for thinness (DT), body dissatisfaction (BD) and cognitive dietary restraint (CRD) were assessed using online surveys. Participants were divided into high fitness (HF) and low fitness (LF) groups by median split and path analyses were conducted. RESULTS: HF and LF women differed significantly (p < .05) in EI [36.0±11.7 vs 40.2±9.7 kcal/kg FFM], PA [196.4±42.1 vs 173.7±31.6 axial counts], PBF [23.2±5.7% vs 29.3±6.2%], BMI [21.7±2.1 vs 23.2±3.0 kg/m2] and VO [41.9±2.5 vs 32.8±5.1 mL/kg/min]. Chi-Square [41.94 with 36 df, p value = 0.23] and CFI [0.85] indicate the models provide a reasonable representation of the data. In both groups, PBF positively correlated with BD [HF: 0.355; LF: 0.406] and negatively correlated with VO2max [HF: -0.487; LF: -0.539]. PBF negatively correlated with DT [-0.252] and positively correlated with EI [0.236] in HF only. PA did not correlate significantly with any variables in the models. CONCLUSION: In college-age women, aerobic fitness appears to be the strongest predictor of body composition, even after adjusting for low and high fitness. HF individuals demonstrated expected relationships between DT, EI and PBF which were not seen in LF individuals. Although PA differed between HF and LF, it was not associated with other variables, particularly PBF. These results emphasize the importance of fitness and physical activity in producing favorable body composition among college-age women.