The Effects of Ice Slurry Ingestion on Repeated-Sprint Ability in Heat

Introduction: Repeated-sprint ability is used to measure the physiological demands of stop-and-go activities. Athletes have a high physiological demand and environmental stress during high heat conditions. Precooling is where you preemptively lower core temperature to increase heat storage capacity. Purpose: The aim of this study was to examine the effect of ice slurry ingestion (0±1°C) vs. water (4°C) prior to the start of and during halftime of a simulated athletic competition in the heat on repeated-sprint cycling in recreationally active college-aged males. Methodology: The researchers used a precooling protocol of 7.5g/kg bodyweight of both water (control) and ice-slurry (experimental) over a 30-minute period prior to the exercise protocol. The participants participated in two, 10 minute halves. Including 5 second sprints, followed by 55 seconds of active recovery at 50 watts. Following the first half of the exercise protocol, participants ingested 2.5 g/kg of ice slurry in the 10 minute passive recovery period. Data collected: core temperature (degrees Celsius), mean power output, peak power output, rating of perceived exertion, heart rate (BPM). Results: There was no significant difference in core temperature, average mean and peak power, and fatigue within condition. There was a statistically significant difference in mean core temperature overall between groups (F=18.36, p=0.00) and fatigue by half within condition (F=5.526, p=0.025). Conclusion: The ice slurry was effective in lowering core temperature, there were no performance enhancements from precooling. Further research needs to be done.