This study investigated the correlation between lower body explosive power and the rate of increase in sprint time with increasing sled weight in a sled-towing exercise. Synthesis of the facts: Eight male sprinters performed tests of lower body explosive power. The rate of increase in sprint time showed a strong correlation with countermovement jump height (r= -0.73) and with normalized peak power in a countermovement jump (r= -0.81) and a squat jump (r= -0.80). Inter-athlete differences in the rate of increase in sprint time might be due to differences in the athlete's power-to-weight ratio. ; This research was supported by a Student Research Grant from the University of Castilla La Mancha (FPI grant, code PRINCET 02/11/2007) and by a grant from the Spanish Ministry of Economy and Competitiveness (DEP2011-28727).