Details

Autor(en) / Beteiligte

• Peel, Jennifer S.
• McNarry, Melitta A.
• Heffernan, Shane M.
• Nevola, Venturino R.
• Kilduff, Liam P.
• Coates, Kathryn
• Dudley, Ed
• Waldron, Mark

Titel

The effect of 8-day oral taurine supplementation on thermoregulation during low-intensity exercise at fixed heat production in hot conditions of incremental humidity

Ist Teil von

• European journal of applied physiology, 2024-09, Vol.124 (9), p.2561-2576

Ort / Verlag

Berlin/Heidelberg: Springer Berlin Heidelberg

Erscheinungsjahr

2024

Quelle

SpringerLink

Beschreibungen/Notizen

• Purpose To determine the effect of taurine supplementation on sweating and core temperature responses, including the transition from compensable to uncompensable heat stress, during prolonged low-intensity exercise of a fixed-heat production (~ 200W/m 2 ) in hot conditions (37.5 °C), at both fixed and incremental vapour-pressure. Methods Fifteen females ( n  = 3) and males ( n  = 12; 27 ± 5 years, 78 ± 9 kg, V ˙ O 2max 50.3 ± 7.8 mL/kg/min), completed a treadmill walking protocol (~ 200W/m 2 heat production [ Ḣ prod ]) in the heat (37.5 ± 0.1 °C) at fixed-(16-mmHg) and ramped-humidity (∆1.5-mmHg/5-min) following 1 week of oral taurine supplementation (50 mg/kg/bm) or placebo, in a double-blind, randomised, cross-over design. Participants were assessed for whole-body sweat loss (WBSL), local sweat rate (LSR), sweat gland activation (SGA), core temperature ( T core ), breakpoint of compensability ( P crit ) and calorimetric heat transfer components. Plasma volume and plasma taurine concentrations were established through pre- and post-trial blood samples. Results Taurine supplementation increased WBSL by 26.6% and 5.1% ( p  = 0.035), LSR by 15.5% and 7.8% ( p  = 0.013), SGA (1 × 1 cm) by 32.2% and 29.9% ( p  < 0.001) and SGA (3 × 3 cm) by 22.1% and 17.1% ( p  = 0.015) during the fixed- and ramped-humidity exercise periods, respectively. Evaporative heat loss was enhanced by 27% ( p  = 0.010), heat-storage reduced by 72% ( p  = 0.024) and P crit was greater in taurine vs placebo (25.0-mmHg vs 21.7-mmHg; p  = 0.002). Conclusion Taurine supplementation increased sweating responses during fixed Ḣ prod in hot conditions, prior to substantial heat strain and before the breakpoint of compensability, demonstrating improved thermoregulatory capacity. The enhanced evaporative cooling and reduced heat-storage delayed the subsequent upward inflection in T core —represented by a greater P crit —and offers a potential dietary supplementation strategy to support thermoregulation.