. 2017 Mar 22;47(Suppl 1):111–128. doi: 10.1007/s40279-017-0691-5

Table 3.

Best practice recommendations for measuring the whole-body sweating rate of athletes in the field

	Whole-body sweating rate
Conditions	Test in conditions (environment, intensity, season, equipment, etc.) representative of training/competition
	Conduct multiple tests within athletes to determine sweating rate in various conditions
Method	Change in body mass, preferably with athlete nude or wearing minimal clothing
Calculation	WBSR = [Body mass_PRE-EX – (Body mass_POST-EX – fluid intake_EX + urine output_EX)]/exercise duration
Additional corrections	Food intake and stool loss (include in the intake and output portion of the above equation, respectively)
Additional corrections	Respiratory water loss and metabolic mass loss, particularly when exercise is >2–3 h, high-intensity, and/or in a dry environment
	Trapped sweat in clothing/uniform, if not obtaining nude body mass
Quality control	Take pre-exercise body mass measurement after athlete voids bladder
	Record any clothing worn during pre- and post-exercise body mass measurements
	Measure pre- and post-exercise body mass in duplicate
	Monitor fluid intake/bathroom breaks between pre- and post-exercise body mass measurements—flag data if fluid intake and urine loss are not measured
	Monitor for spitting/squirting of fluid from drink bottles—flag data if not controlled/prevented; offer a separate bottle of water if athletes want to use it for body cooling purposes (e.g. squirting on face, dumping on head, etc.)

See text for discussion and supporting references

EX during exercise (i.e. between pre- and post-exercise body mass measurements), PRE-EX pre-exercise, POST-EX post-exercise, WBSR whole-body sweating rate (typically expressed as mL/h or L/h)