The freshmen weight gain: Is it more about body composition than weight?

Abstract

Objective. The purpose of the study was to examine predictors of change in body weight and composition among freshmen during an academic year. Research methods and procedure. Twenty-nine freshmen, 16 females (58.2+/-10.4 kg; BMI 21.2+/-2.9 kg/m2) and 13 males (74.6+/-11.9 kg; BMI 23.2+/-2.8 kg/m2) completed the study. Body weight and composition (DEXA), waist circumference (WC), energy intake (7-day food diary) and activity-related energy expenditure (accelerometry) were measured in September, December and March. The TFEQ and VO2peak were assessed at baseline. Results. Significant increases in body weight (1.9+/-2.0 kg, P<0.05), BMI (0.6+/-0.7 kg/m2, P<0.05), WC (2.7+/-3.0 cm, P<0.05), % body fat (BF) (3.1+/-2.3%, P<0.01) and fat mass (2.6+/-1.8 kg, P<0.01) were noted in males, especially over the 1 st semester. No significant changes were observed in females. Correlations with females and males pooled together showed that over the academic year, baseline % body fat was associated with changes in weight and %BF ( r=-0.53, P<0.01; r=-0.41, P<0.05, respectively). Baseline %BF predicted 27% (P<0.05) of the change in weight. Baseline alcohol intake was related with changes in WC (r=0.45, P<0.05) and %BF ( r=0.58, P<0.01). It explained 34% (P <0.01) and 17% (P<0.05) of the changes respectively. The change in weight and %BF were also associated with baseline VO2peak (r=0.51, P<0.01; r=0.48, P<0.01; respectively). Dietary restraint also effected the change in % body fat (r=-0.43, P<0.05). Discussion. Males, leaner freshmen, physically fit freshmen experienced greater increases in body weight, adiposity and abdominal fat. The best predictor of change in BF was baseline alcohol intake. Keywords. freshmen, weight gain, body composition, waist circumference, energy balance