2019

Author(s): Chalmers S, Siegler J, Lovell R, Lynch G, Gregson W, Marshall P and Jay O

OBJECTIVES: The study examined if three feasible strategies involving additional in-play cooling periods attenuate the core (rectal) temperature rise during simulated football matches. DESIGN: Four counterbalanced experimental trials in an environmental chamber set to 35 degrees C ambient temperature, 55% relative humidity, and 30 degrees C WBGT. METHODS: Twelve healthy well-trained football players completed a regular simulated match (REG), regular simulated match with additional 3-min cooling periods at the 30-min mark of each half inclusive of chilled water consumption (COOLwater), regular simulated match with additional 3-min cooling periods at the 30-min mark of each half inclusive of chilled water consumption and the application of an ice towel around the neck (COOLtowel), regular simulated match with an extended (+5min; total of 20-min) half-time break (HTextended). RESULTS: The difference in rectal temperature change was significantly lower in the COOLwater (-0.25 degrees C), COOLtowel (-0.28 degrees C), and HTextended (-0.21 degrees C) trials in comparison to the REG (all p<0.05). Exercising heart rate and session rating of perceived exertion was lower in the COOLwater (-13bpm; -1.4au), COOLtowel (-10bpm; -1.3au), and HTextended (-8bpm; -0.9au) trials in comparison to the REG trial (all p<0.05). The cooling interventions did not significantly change skin temperature or thermal sensation in comparison to the REG (all p>0.05). CONCLUSIONS: All three cooling interventions attenuated core body thermal strain during simulated matches. The laboratory-based study supports the use of brief in-play cooling periods as a means to attenuate the rise in core temperature during matches in hot and humid conditions.

Journal: Journal of Science and Medicine in Sport