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Updated: Mar 18, 2026

Skeletal Muscle Gender Dimorphism from Proteomics
Published on: December 14, 2011
Characteristics of Anabolic-Androgenic Steroid-Free Competitive Male and Female Bodybuilders
Abstract:
In brief: Anabolic-androgenic steroids are widely used in the community of bodybuilders. We defined a group of steroid-free bodybuilders by analyzing urine for the presence of these steroids, and compared the bodybuilders with both sedentary controls and runners. Male and female competitive bodybuilders had low percentages of body fat. One third of the female bodybuilders reported menstrual abnormalities (more than three missed menses during the past 12 months). Lipid values of bodybuilders were comparable to a group of lean, aerobically trained athletes. Despite their high volume of training, the bodybuilders' oxygen uptake during cycle ergometry was augmented only in proportion to the increase in lean body mass.
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