Levels of nine serum hormones, six skin-fold sites, and body weight were measured in 19 male amateur wrestlers during their competitive season and again two months after the season. Percent of body fat was estimated from skin-fold thicknesses. Body weight, body fat, testosterone level, and prolactin level were significantly lower during the wrestling season. Low serum testosterone levels were significantly correlated with low body fat, large loss of body fat, and large weight loss. These findings suggest that the dietary restriction practiced by some wrestlers may affect serum testosterone levels adversely.