Efficacy of the FIFA cooling break heat policy during an intermittent treadmill football simulation in hot conditions in trained males
Harry A. Brown, Samuel Chalmers, Thomas H. Topham, Brad Clark, Andrew Jowett, Tim Meyer, Ollie Jay, Julien D. Périard
Abstract
Objective To evaluate the efficacy of the Fédération Internationale de Football Association (FIFA) cooling break policy against alternative cooling configurations in attenuating thermal strain during simulated football in the heat. Methods 12 males (age: 27±6 years, V̇O 2peak : 61±7 mL/kg/min) completed five 90 min intermittent treadmill football match simulations in 40°C and 41% relative humidity (32°C wet-bulb globe temperature) with different cooling configurations: regular match without cooling breaks (REG), 3 min breaks without cooling (BRK no-cool ), 3 min breaks with cooling (BRK cool : current FIFA policy; chilled fluid ingestion and ice towel across neck and shoulders), 5 min extended half-time without cooling breaks (ExtHT only ) and 3 min cooling breaks with 5 min ExtHT (ExtHT cool ). Rectal temperature (T re ), heart rate, whole-body sweat rate (WBSR) and rating of perceived exertion (RPE) were recorded. Data are presented as mean (95% CIs). Results Final T re was lower in BRK no-cool (0.20°C (0.01, 0.39), p=0.038), BRK cool (0.39°C (0.21, 0.57), p<0.001) and ExtHT cool (0.40°C (0.22, 0.58), p<0.001) than REG (39.1°C (38.8, 39.3)). Mean T re was lower in ExtHT cool (38.2°C (38.0, 38.4)) than BRK cool (38.3°C (38.1, 38.5), p=0.018), BRK no-cool and ExtHT only (38.4°C (38.2, 38.6), p<0.001) and REG (38.5°C (38.3, 38.7), p<0.001). Mean heart rate was lower during BRK cool (6 beats/min (4, 7), p<0.001) and ExtHT cool (7 beats/min (6, 8), p<0.001) compared with REG. WBSR was comparable across trials (p ≥ 0.07) and RPE was attenuated during BRK cool (0.4 (0.1, 0.7), p=0.004) and ExtHT cool (0.5 (0.2, 0.7), p=0.002), compared with REG. Conclusion BRK cool and ExtHT cool attenuated thermal, cardiovascular and perceptual strain during a simulated football match in the heat. Additional strategies may be required in field settings or under harsher conditions.