TY - JOUR T1 - Core temperature up to 41.5ºC during the UCI Road Cycling World Championships in the heat JF - British Journal of Sports Medicine JO - Br J Sports Med SP - 426 LP - 429 DO - 10.1136/bjsports-2018-099881 VL - 53 IS - 7 AU - Sebastien Racinais AU - Sebastien Moussay AU - David Nichols AU - Gavin Travers AU - Taoufik Belfekih AU - Yorck Olaf Schumacher AU - Julien D Periard Y1 - 2019/04/01 UR - http://bjsm.bmj.com/content/53/7/426.abstract N2 - Objective To characterise the core temperature response and power output profile of elite male and female cyclists during the 2016 UCI Road World Championships. This may contribute to formulating environmental heat stress policies.Methods Core temperature was recorded via an ingestible capsule in 10, 15 and 15 cyclists during the team time trial (TTT), individual time trial (ITT) and road race (RR), respectively. Power output and heart rate were extracted from individual cycling computers. Ambient conditions in direct sunlight were hot (37°C±3°C) but dry (25%±16% relative humidity), corresponding to a wet-bulb globe temperature of 27°C±2°C.Results Core temperature increased during all races (p<0.001), reaching higher peak values in TTT (39.8°C±0.9°C) and ITT (39.8°C±0.4°C), relative to RR (39.2°C±0.4°C, p<0.001). The highest temperature recorded was 41.5°C (TTT). Power output was significantly higher during TTT (4.7±0.3 W/kg) and ITT (4.9±0.5 W/kg) than RR (2.7±0.4 W/kg, p<0.001). Heart rate increased during the TTs (p<0.001) while power output decreased (p<0.001).Conclusion 85% of the cyclists participating in the study (ie, 34 of 40) reached a core temperature of at least 39°C with 25% (ie, 10 of 40) exceeding 40°C. Higher core temperatures were reached during the time trials than the RR. ER -