An Aggregate Urine Analysis Tool to Detect Acute Dehydration
2013 (English)In: International Journal of Sport Nutrition & Exercise Metabolism, ISSN 1526-484X, Vol. 23, no 4, 303-311 p.Article in journal (Refereed) Published
Urine sampling has previously been evaluated for detecting dehydration in young male athletes. The present study investigated whether urine analysis can serve as a measure of dehydration in men and women of a wide age span.
Urine sampling and body weight measurement were undertaken before and after recreational physical exercise (median time: 90 minutes) in 57 volunteers aged between 17 and 69 years (mean age: 42). Urine analysis included urine color, osmolality, specific gravity, and creatinine.
The volunteers' body weight decreased 1.1% (mean) while they exercised. There were strong correlations between all four urinary markers of dehydration (r = 0.73 to 0.84, P < 0.001). Researchers constructed a composite dehydration index graded from 1 to 6 based on these markers. This index changed from 2.70 before exercising to 3.55 after exercising, which corresponded to dehydration of 1.0% as given by a preliminary reference curve based on seven previous studies in athletes. Men were slightly dehydrated at baseline (mean: 1.9%) compared to women (mean: 0.7%; P < 0.001), while age had no influence on the results. A final reference curve that considered both the present results and the seven previous studies was constructed in which exercise-induced weight loss (x) was predicted by the exponential equation x= 0.20 dehydration index.
Urine sampling can be used to estimate weight loss due to dehydration in adults up to the age of 70 years. A robust dehydration index based on four indicators reduces the influence of confounders.
Place, publisher, year, edition, pages
Human Kinetics , 2013. Vol. 23, no 4, 303-311 p.
urine color, osmolality, creatinine, specific gravity
Medical and Health Sciences
IdentifiersURN: urn:nbn:se:liu:diva-97670ISI: 000323649500001PubMedID: 23239678OAI: oai:DiVA.org:liu-97670DiVA: diva2:649976