The rate of eccrine sweating has been studied by collecting samples in unventilated capsules from human subjects following subdermal or intradermal injections of acetyl-β-methylcholine and under moderate total body heat exposure. The rate of sweating in a given area of skin could increase by recruitment of fresh glands, enhanced output of the already active glands, or some combination of both.

A theoretical analysis shows how recruitment and enhancement can be calculated separately, assuming the existence of a maximal rate of sodium reabsorption by eccrine sweat glands, a sodium concentration of 145 μEq/ml in the precursor fluid, the absence of significant water reabsorption, and the absence of back-diffusion of sodium. The results indicate that, depending on the experimental conditions, an increased rate of sweating can be attributed mainly to recruitment, to enhancement, or to a combination of both.