Sweat Lactate, Ammonia, and Urea in Rugby Players

Abstract

The purpose of this study was to investigate sweat lactate, ammonia, and urea excretion in rugby players. Fifteen elite amateur rugby players volunteered to participate. The study was conducted during competitive matches in the official season. Plasma and sweat concentrations of lactate, ammonia, and urea were measured before and after the matches. Peak values for creatine kinase activity were observed 24 h after the match. There was no significant change between time points for blood lactate concentration but secretion rate per unit surface and time was significantly reduced after the match. Sweat ammonia concentration increased significantly during the match; values were significantly reduced after 24 h and still remained low at 72 h. Secretion rate was also reduced from 24 h. Urea concentration was significantly reduced at 48 h, while secretion rates decreased at 24 h and 48 h. Lactate in blood was significantly elevated during the match but not thereafter. Blood ammonia was significantly elevated during the match and did not differ from the resting values at 24 or 48 h. Urea in blood tended to decrease during the match, with a significant reduction at 24 h. Significant positive correlations were observed between blood and sweat concentrations for urea and ammonia but not for lactate. Sweat rate correlated positively with sweat lactate secretion. The fact that part of the ammonia formed during exercise is lost with sweat indicates the importance of the purine nucleotide cycle during rugby matches. Our data also confirm that sweat lactate concentration is not influenced by circulatory blood lactate in rugby players.

Longitudinal Follow-Up of Biochemical Markers of Fatigue Throughout a Sporting Season in Young Elite Rugby Players

“…This finding is in contrast with the results of Burr et al (5) but in accordance with the observations of Fallon et al (10). The only data available regarding rugby players measured uremia and observed a reduction during competitions (1).…”

The microfluidics of the eccrine sweat gland, including biomarker partitioning, transport, and biosensing implications

“…24,61,62 Ammonia is also of interest because it is a possible and needed substitute for lactate measurement of anaerobic condition (see Subsection IV H). Ammonia (NH 3 ) passes through the cells lining the secretory coil by means of a passive diffusive mechanism.…”

“…Several studies 24,25,78 have experimentally investigated the relationship between plasma and sweat lactate levels after exercise, with widely ranging sweat concentrations as low 24 as $6 mM and as high 21 as $100 mM.…”

“…2,23 High exertion exercise tests can therefore show a spike in lactate correlating with exercise intensity (sweat rate), but this does not necessarily represent the anaerobic state of the body. [24][25][26] In addition to concerns with sweat rate dependence or metabolic relationships, there are also issues of contamination from the surface of the skin. For instance, it has been shown that glucose levels in sweat do trend with glucose levels in blood.…”

Systematic Review Focusing on the Excretion and Protection Roles of Sweat in the Skin

“…They also observed that the concentration of creatinine and uric acid in sweat was relatively low, whereas the urea concentration was significantly higher (50-fold in some cases) compared with that in the serum. Therefore, it was suggested that selective transport [23,24] of high blood levels of urea by sweating with thermal induction could be a potential treatment for dialysis patients. It has also been shown that other proteins or peptides, such as cysteine proteinases [25] and kallikrein [26], are present in sweat.…”