Master of Science (M.S.)
Degree Granting Department
Education and Psychological Studies
Candi Ashley, Ph.D.
Rebecca Lopez, Ph.D.
Marcus Kilpatrick, Ph.D.
beverage temperatures, ice slushy, precooling
Precooling is a method used to decrease initial pre-exercise core temperature in order to facilitate a greater margin for heat production before a maximum core temperature is reached. The purpose of this study was to examine the differences in physiological and perceptual effects of precooling using beverages of three different temperatures: room temperature beverage (24.88 ± 1.13°C), cold beverage (6.15 ± 3.16°C) and ice slushy (-1.61 ± 0.45°C) in a hot environment (27.88 ± 0.72°C and 35.36 ± 0.83°C for wet globe bulb temperature and dry bulb temperature respectively). For all trials the environmental temperature was set to 35°C with 56% rh.
For this study, 10 physically active females (age= 23.7 ± 2.26 years, height=1.74 ± 0.23 m, weight=66.27 ± 0.92 kg, BMI=24.14 ± 2.63 kg/m2, body fat= 22.99 ± 2.37% and VO2 max= 43.61 ± 4.78 ml/kg/min) participated in the study. On three separate occasions participants precooled via beverage consumption over a 30-minute period with a 5-minute rest period before beginning a 45-minute interval treadmill protocol. Following exercise, participants then re-cooled for 15 minutes. Each subject precooled and re-cooled with all three beverages at their respective temperature. Treatments were randomized.
There were no significant differences found for TGI during precooling, exercise or re-cooling Mean HR and mean TSK during precooling were significantly lower in the ice slushy trial as compared to the room temperature trial (HR = 75.7 ± 15.7 and 80.1 ± 16.4 bpm; respectively, p < 0.05 ; TSK = 34.47 ± 0.74 and 34.21 ± 0.92ºC; respectively, p < 0.05). There was also a significant difference in thermal sensation during precooling among all three beverage temperatures (Thermal sensation = 4.7 ± 0.7, 4.5 ± 0.7 and 4.0 ± 0.7; for room, cold, and ice slushy respectively, p < 0.05). Mean thirst sensation for ice slushy was also significantly lower during precooling when compared to cold (p < 0.05) and room temperature beverages (p < 0.05). Mean thirst sensation was also significantly lower during exercise for ice slushy compared to cold (p < 0.05) and room temperature (p < 0.05) (precooling thirst sensation= 2.3 ± 1.0, 2.1 ± 1.1 and 1.6 ± 1.0; exercise 4.1 ± 2.0, 4.5 ± 1.7 and 3.2 ± 1.6 for room, cold and ice slushy respectively). During re-cooling mean thirst sensation was significantly lower for ice slush as compared to room temperature (p < 0.05).
Results from the current study suggest that precooling with an ice slushy as compared to a cold or room temperature beverage had little to no effect on TGI and a small effect on HR and TSK during precooling. Although, precooling with an ice slushy appeared to be effective at decreasing perceptual measurements.
Scholar Commons Citation
Welch, Taylor, "The Physiological Effects of Precooling Beverage Temperatures on Heat Strain in Collegiate Women Soccer Players" (2014). Graduate Theses and Dissertations.