Separate and combined effects of dehydration and thirst sensation on exercise performance in the heat

Using intravenous infusion, we separated the physiologic consequences of 3% body mass dehydration from the conscious awareness of fluid replacement on time trial (TT) performance in the heat. Eleven trained cyclists performed 90 min of steady-state (50% V ˙ O 2 peak ) cycling followed by a self-paced 20-km TT in a hot-dry (35 °C, 10% relative humidity, wind speed 3.0 m/s) environment while euhydrated-not thirsty (EU-NT), euhydrated-thirsty …