The relationship between platelet count, bodyfat, and Harvard step test score was examined in 15 post-absorptive male subjects. Subjects rested for five minutes at the beginning of the testing period. A fingertip blood sample was then obtained and the platelet count determined by the method of Brecher and Cronkite. One-percent ammonium oxalate was employed as the dilution fluid. Bodyfat was calculated with the Siri formula on the basis of skinfolds obtained by the method of Pascale. Testing was concluded with the Harvard step test in a controlled environment room. Pearson product-moment correlation calculations yielded no significant relationship (P=>.05) between platelet count and bodyfat or platelet count and Harvard step test score. Subjects were equated by age matching into lean (under 9.9%), average (10-14.9%), and overweight (above 15%) bodyfat groups. An analysis of variance (ANOVA) revealed no significant difference (P>.05) between the platelet counts of these groups.