Body composition changes in female bodybuilders during preparation for competition

Area of Science:

• Sports Science
• Human Physiology
• Body Composition Analysis

Background:

• Female bodybuilders undergo rigorous training and dietary changes to achieve a specific physique for competition.
• Understanding body composition changes during preparation is crucial for optimizing performance and health.

Purpose of the Study:

• To investigate anthropometric and body composition alterations in female bodybuilders during the 12 weeks leading up to a competition.
• To compare these changes against a control group of athletic females.

Main Methods:

• A longitudinal study involving five competitive female bodybuilders and five controls matched for height and body fat percentage.
• Measurements included anthropometry, body density (underwater weighing), total body water (deuterium dilution), and bone mineral mass (DXA) to determine body fat percentage via a four-compartment model.
• Data collected at 12 weeks, 6 weeks, and 3-5 days pre-competition.

Main Results:

• Bodybuilders lost an average of 5.80 kg body mass, with 76.2% attributed to fat mass reduction and 23.8% to fat-free mass reduction.
• Body fat percentage decreased significantly from 18.3% to 12.7% in bodybuilders, while controls remained stable.
• A significant reduction in skinfold thickness sum (25.5 mm) was observed in the bodybuilders.

Conclusions:

• Female bodybuilders achieve significant body mass and fat mass reduction during competition preparation, even with initially low body fat percentages.
• The primary mechanism for mass loss is a reduction in fat mass, preserving fat-free mass to a considerable extent.
• These findings highlight the effectiveness of their preparation strategies in achieving desired body composition.