Body composition changes in female bodybuilders during preparation for competition

Objective: To determine anthropometric and body composition changes in female bodybuilders during preparation for competition. Design: There was an attempt to match subjects in the control and experimental groups for height and percentage body fat (%BF) for the initial test of this longitudinal study. Subjects: Five competitive bodybuilders (-X±s.d.: 35.3±5.7 y; 167.3±3.7 cm; 66.38±6.30 kg; 18.3±3.5 %BF) and five athletic females (-X±s.d.: 30.9±13.0 y; 166.9±3.9 cm; 55.94±3.59 kg; 19.1±3.3 %BF) were recruited from advertisements in a bodybuilding newsletter and placed on sports centre noticeboards. Interventions: The following measurements were conducted 12 weeks, 6 weeks and 3–5 d before the bodybuilders' competitions: anthropometric profile, body density by underwater weighing, total body water via deuterium dilution and bone mineral mass from a dual-energy X-ray absorptiometry scan. A combination of the last three measurements enabled the %BF to the determined by a four compartment model. Results: A significant (P≤0.001) 5.80 kg body mass loss by the bodybuilders as they prepared for competition was primarily due to a reduction in fat mass (FM; −4.42 kg; 76.2%) as opposed to fat-free mass (FFM; −1.38 kg; 23.8%). The decreases in body mass and FM over the final 6 weeks were greater than those over the first 6 weeks. Their %BF decreased (P<0.001) from 18.3 to 12.7, whereas the values for the control group remained essentially unchanged at 19.1–19.6 %BF. These body composition changes by the bodybuilders were accompanied by a significant decline (P