To examine thermal pain perception before, 5 minutes after, and 30 minutes after 30 minutes of treadmill exercise at 75% of maximal oxygen uptake (V o 2 max).Repeated-measures.Sports science laboratory.Convenience sample of 14 healthy male and female volunteers (mean age +/- standard deviation, 32+/-3y).Sensory thresholds, pain thresholds, and pain ratings to hot and cold stimuli were measured before and after 30 minutes of treadmill exercise at 75% of V o 2 max. The hot and cold stimuli were delivered by using a thermode placed on the thenar eminence of the nondominant hand. Thermal sensory and pain thresholds were determined during continuous ramps in temperature of the thermode.Pain ratings were measured on a visual analog scale at 10-second intervals over 2 minutes of thermal pain stimulation.There were no significant changes in thermal sensitivity, pain thresholds, or pain ratings for either heat or cold after 30 minutes of exercise at 75% of V o 2 max.Pain perception to thermal stimuli was unaltered after 30 minutes of exercise at 75% of V o 2 max, an intensity and duration of exercise previously shown to alter pain perception to electric and mechanical stimuli.