Effect of cold water immersion on serum levels of lactate and performance following an exhaustive exercise in the heat conditions
Poster Presentation XML
Paper ID : 1318-11THCONF
University of Zanjan
Introduction: Increase in body temperature in the warm and humid conditions is the main limiting factor in long-term activities. Hence, researchers are constantly looking for ways to avoid the loss of physical function in the high temperatures. Thus, the purpose of this study was to determine the effect of cold water immersion on exhaustion time and serum levels of lactate of untrained men following an exhaustive exercise in the heat conditions.
Methodology: The research was included pre-test/post-test control group design. The participants were 20 untrained male students of the University of Zanjan aged 19 to 21. Core temperature, skin temperature, heart rate, blood pressure and plasma lactate were measured in three stages: (1- baseline, 2- after warm up and pre-cooling and 3- After exhaustive test). Warming-up was running on the treadmill at the speed of 7 km/h. The pre-cooling method was immersion in cold water (26 °C) for 10 minutes (ambient temperature 32-34 °C). Exhaustive exercise protocol included running in the hot environment (33 °C, 50% humidity) on the treadmill at the speed of 7 k/h; speed was increased by 1 km/h every minute. When the speed reached to 10 km/h participants ran until volitional exhaustion at this velocity. The one-way analysis of covariance (ANCOVA) was used to compare differences between groups. SPSS 16 was used for statistical analysis. The significance level was set at P≤0.05 for all comparisons.
Results: Statistical analysis indicated that time to exhaustion in the pre-cooling group significantly increased (p≤0.05). However, heart rate, skin temperature, and plasma lactate were significantly decreased in the pre-cooling group (p≤0.05).
Discussion: The findings showed that pre-cooling can improve cardiovascular efficiency, endurance performance, and metabolic profiles during physical activity in the heat. In high-temperature conditions, pre-cooling can delay in the raising skin blood flow; therefore, it provides optimal temperature for metabolism enzymes' activity, prevents elevation of blood lactate and results in high running performance.