The influence of work loads (20, 40 and 60% VO2max) on regional differences in sweating rates was investigated in six healthy male students. The ratios of local sweating rate (msw) on the chest and back to estimated total sweating rate (mean msw of four sites examined x body surface area) at 20% work load were significantly greater than those on the forearm and forehead, whereas the ratio on the forehead at 60% work load was greater than at the other sites. The ratios on the forearm at 40 and 60% work loads were significantly greater than at 20% work load. The regional differences in sweating rates change with the increase in work load as seen by the greater variation in the ratios of msw on each site at 20% work load compared with 40 and 60% work loads. The results indicate that redistribution of this sweat activity to whole body or head with the rise in work load induces favorable conditions for evaporation and controlling brain temperature.