Effect of a precompetition bodybuilding diet and training regimen on body composition and blood chemistry.

OBJECTIVE The purpose of this investigation was to document the effect of a 10-wk precompetition bodybuilding diet and training, on blood chemistry and body composition. PARTICIPANT One adult male, steroid and drug free, preparing for a first competition. MEASURES Average daily dietary intake consisted of 2263 calories (71% protein, 16% carbohydrate, 13% fats), with a protein intake of 5.0 gm.kg-1 body mass (BM). Initial body weight of 76.3 kgf (16% body fat) decreased to 63.4 kgf (4.4% body fat). Blood samples for electrolytes, TP, Alb, bilirubin, LDL-C, TG, UA, and amylase were normal. HDL-C levels increased from 65 to 89 mg.dL-1. RESULTS Decreased glucose levels (< 50 mg.dL-1), indicated hypoglycemia. Increased Mg, LD, and CK levels indicated intense training. Increased inorganic phosphorus from 3.7 to 8.2 mg.dL-1 suggested lactic acidosis. Increased BUN levels from 16 to 53 mg.dL-1 and creatinine from 1.1 to 1.8 mg.dL-1 may be attributed to a high protein diet. However, heart muscle enzyme (CK-MB) was not elevated. CONCLUSIONS Substantial changes in body composition and blood chemistry suggest adequate nutrition be ensured, and caution taken to avoid excessive physiologic stresses on the body during precompetition diet and training.