Effects of warm-up and precooling on endurance performance in the heat

Br J Sports Med. 2007 Jun;41(6):380-4. doi: 10.1136/bjsm.2006.032292. Epub 2007 Jan 15.

Abstract

Objective: To examine the effects of different thermoregulatory preparation procedures (warm-up (WU), precooling (PC), control (C)) on endurance performance in the heat.

Methods: 20 male subjects completed three treadmill runs to exhaustion (5 days apart). In each session, all subjects performed an incremental running test after WU (20 min at 70% maximum heart rate (HR)), after PC (wearing a cooling vest (0 degrees C-5 degrees C) for 20 min at rest) or without particular preparation (C). After a 5-min break, the exercise protocol commenced at a workload of 9 km/h and was increased by 1 km/h every 5 min until the point of volitional fatigue. Running performance, HR, blood lactate concentration, tympanic temperature and skin temperature were measured in each trial.

Results: In the PC condition, the running performance (32.5 (5.1) min; mean (SD)) was significantly (p<0.05) higher than in WU (26.9 (4.6) min) and in C conditions (30.3 (4.3) min). During the first 30 min of testing, HR, tympanic temperature and skin temperature were significantly (p<0.05) lower after PC than after WU. There were no significant differences in lactate concentration; however, there was a trend to lower values after WU.

Conclusions: The use of an ice-cooling vest for 20 min before exercising improved running performance, whereas the 20 min WU procedure had a distinctly detrimental effect. Cooling procedures including additional parts of the body such as the head and the neck might further enhance the effectiveness of PC measures.

Publication types

  • Randomized Controlled Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Body Temperature / physiology
  • Body Temperature Regulation / physiology*
  • Cryotherapy / instrumentation
  • Cryotherapy / methods*
  • Exercise / physiology*
  • Heart Rate / physiology
  • Hot Temperature*
  • Humans
  • Lactic Acid / blood
  • Male
  • Physical Endurance / physiology*
  • Running / physiology
  • Task Performance and Analysis

Substances

  • Lactic Acid