Ice slurry ingestion during break times attenuates the increase of core temperature in a simulation of physical demand of match-play tennis in the heat

Abstract

This investigation assessed the effect of ice slurry ingestion compared to that of cold water ingestion during break times on thermal strain and perception in simulated match-play tennis in the heat. Seven male recreational athletes (age = 22 ± 2 yr, height = 1.72 ± 0.08 m, Body mass = 64.8 ± 6.8 kg) performed two trials in a climate chamber, each time completing 4 sets of simulated match-play. During International Tennis Federation-mandated breaks (90-s between odd-numbered games; 120-s between sets), either ice slurry or cold water were ingested. The rectal temperature, forehead skin temperature, heart rate, rating of thermal comfort and total sweat loss were measured. The change in rectal temperature in the ice slurry trial was significantly lower than that in the cold water trial by game 3 of set 3 (p = 0.02). These differences in Δrectal temperature persisted throughout the remainder of the "match" (p < 0.05). Forehead skin temperature, heart rate and rating of thermal comfort were significantly lower in the ice slurry trial than in the cold water trial by the second half of the experiment (p < 0.05). Total sweat loss in ice slurry trial is significantly lower than cold water trial (p = 0.002). These results suggested that ice slurry ingestion was more effective than cold water ingestion in mitigating the development of heat strain during simulated match-play tennis in the heat.

Impact of Ice Slurry Ingestion During Break-Times on Repeated-Sprint Exercise in the Heat

“…In this study, the total sweat volume was lower in the ICE trial than that in the CON trial. This finding is consistent with previous studies, which reported that the use of ice slurry ingestion during exercise reduced total sweat volume compared to ingestion of cold water [12]. However, it is speculated that the reduction of total sweat volume may appear to decrease the potential for evaporative heat loss from the skin.…”

“…Ingesting ice slurry at HT only may not improve performance by a heat-sink effect on exercise performance. In contrast, Naito et al [12] demonstrated that ice slurry ingestion (1.25 g•kg body mass [BM] -1 ) during break times (19 times) of a tennis match simulation attenuated the rise of Tre from the second half of exercise until the end of exercise, but exercise performance was not measured in this study.…”

“…Moreover, it is possible that improvements in perceptual sensations are due to the rise of Tsk [24,26] and Thead [14]. Conductive cooling by oral ingestion of ice slurry may allow direct attenuation of the rise of Thead [12] and brain temperature [27] measured by magnetic resonance spectroscopy. Therefore, it is speculated that the improvements of perceptual sensation using ice slurry ingestion were influenced by cold-sensitive thermal afferents, from the peripheral to the central, and attenuated both peripheral and brain temperatures.…”

Tokyo-2020ne, Temperature and time for reflection

“…Kajiki et al [5] demonstrate that when continuous air is blown onto the back and neck from two fans attached to the sides of the rucksack, physiological and perceptual responses are reduced during light activity in the heat. Results from the Japanese Institute of Sport Sciences [6] provide an alternative cooling strategy; an ice-slurry was used during a trial simulating tennis match-play. Whilst Naito and colleagues [6] cannot offer the women's singles gold medalist protection from harmful ultraviolet exposure, they can reduce her thermoregulatory and perceptual responses to mitigate heat strain.…”

Ice slurry ingestion as a cooling strategy in the heat

“…However, the volume of ad libitum ice slurry ingested during exercise was lower than the volume of cold fluid intake; therefore, there was no significant difference in rectal temperature. Naito et al 24) found that intermittent ice slurry ingestion during simulated matchplay tennis maintained a lower rectal temperature than did ingestion of cold water. In that study, participants consumed approximately 1600 g of ice slurry, which is twice the volume in the study by Maunders 23) .…”