The effect of ice slurry ingestion on body temperature and cycling performance in competitive athletes

Abstract

The effects of pre cooling on endurance performance are widely known. In contrast, the approach of cooling during endurance exercise in combination with pre-exercise cooling has been poorly understood. The purpose of the present study was to determine whether the effects of precooling and cooling during exercise enhance exercise performance compared to the ingestion of a thermo-neutral beverage (20 °C) or precooling alone in cycling performance. This was an experimental study using a randomised crossover design in which 7 cyclists underwent three trials comprising of 45 min steady state cycling (SS) at 70% VO max and a subsequent 10 km time trial (TT) in hot conditions (32 °C, 50% relative humidity). Rectal temperature (T), heat storage (HS), heart rate (HR), blood lactate concentration (BLA) and thermal sensation (TS) were measured. The intervention consisted of: (1) ingestion of thermo-neutral beverage before and during SS cycling (TN), (2) ingestion of ice slurry beverage and application of iced towels (precooling) prior to exercise, and then ingestion of thermo-neutral beverage during SS (PRE) and (3) precooling strategy as above plus ice slurry ingestion during SS cycling (PRE + MID). The intake of thermo-neutral or ice slurry beverage (14 g/kg) occurred over 30 min before and every 15 min during SS cycling. There was no significant difference in TT performance between all the conditions (P =0.72). However, PRE and PRE + MID caused a significant decrease in T (P < 0.05) from TN during exercise. Accordingly, both precooling and a combination of precooling and mid-cooling during exercise in hot conditions may be a practical and effective way of reducing core temperature. Future studies should investigate longer distance events and timing of ice slurry ingestion.

A novel vest with dual functions for firefighters: combined effects of body cooling and cold fluid ingestion on the alleviation of heat strain

“…There are similar studies reporting the effect of ice slurry ingestion on the reduction of rectal temperature, heart rate and skin temperature (0.8-1.4% body mass) 30,[72][73][74] . However, those studies were conducted on cyclists wearing light clothing.…”

“…Providing cold drinking water to minimize dehydration can be an effective intervention strategy to offset the impact of heat stress. The effects of drinking ice slurry on the body temperature of cyclists has been documented 30) . Faster reaction time when subjects were hydrated 26) might extremely beneficial for firefighters who need to make snap judgments under emergency situations.…”

Ice slurry ingestion as a cooling strategy in the heat

“…Moreover, ice slurry can be made from sports drinks, which include carbohydrates and electrolytes. Thus, ice slurry ingestion contributes to nutrient delivery and sustains hydration status 17) . In this way, ingestion of ice slurry can be an effective and practical cooling method under high temperatures.…”

The elderly's physiological and perceptual responses to cooling during simulated activities of daily living in UK summer climatic conditions

“…With regard to acute 16 heat-alleviation, research with a focus on the elderly is limited to the effects of electrical 17 fans [15][16][17] which is surprising given the plethora of research on acute practical cooling 18 strategies to reduce physiological strain within athletic and occupational 19 populations. 14,[18][19][20] Consequently, it has yet to be determined whether the benefits of 20 acute practical cooling strategies in young healthy populations can be replicated in an 21 elderly population and attenuate the risk of heat-related illness. Prevention of heat illness in the elderly requires an intervention with cooling modalities 24 pre or during (i.e., per-cooling) activity, in line with existing research conducted with 25 younger population.…”