Body map of regional vs. whole body sweating rate and sweat electrolyte concentrations in men and women during moderate exercise-heat stress

This study determined the relations between regional (REG) and whole body (WB) sweating rate (RSR and WBSR, respectively) and REG and WB sweat [Na+] during exercise. Twenty-six recreational athletes (17 men, 9 women) cycled for 90 min while WB sweat [Na+] was measured using the washdown technique. RSR and REG sweat [Na+] were measured from 9 regions using absorbent patches. RSR and REG sweat [Na+] from all regions were significantly (p<0.05) correlated with WBSR (r=0.58-0.83) and WB sweat [Na+] [r=0.74-0.88), respectively. However, the slope and y-intercept of the regression lines for most models were significantly different than 1 and 0, respectively. The coefficients of determination (r2) were 0.44-0.69 for RSR predicting WBSR (best predictors: dorsal forearm (r2=0.62) and triceps (r2=0.69)) and 0.55-0.77 for REG predicting WB sweat [Na+] (best predictors: ventral forearm (r2=0.73) and thigh (r2=0.77)). There was a significant (p<0.05) effect of day-to-day variability on the regression model predicting ...