Table 1.
Studies with average power output reported for prolonged time trials (TT duration above 30 min.) in the heat (30°C or above) and with a corresponding cool control trial (20°C or below).
| Reference | Temperature (°C) | Relative Humidity (and vapor pressure) | Wind speed (m/s) | Peak heart rate HOT (CON) | Sweat rate L/h HOT (CON) | End core temperature HOT (CON) | Power output deficit compared to control |
|---|---|---|---|---|---|---|---|
| Racinais13* | 39°C | 20% (9 mmHg) | 9.5 | 175 (169) | 2.1 | 40.2 (38.5)°C | 16% |
| Racinais13 ** | 39°C | 20% (9 mmHg) | 11 | 177(169) | 2.5 | 40.1 (38.5)°C | 2% |
| Lorenzo33* | 38°C | 30% (15 mmHg) | 0.5 | 165 | — | 39.5 (38.8)°C | 18% |
| Lorenzo33 ** | 38°C | 30% (15 mmHg) | 0.5 | 150 | — | 39.4 (38.8)°C | 17% |
| Périard72 | 35°C | 60% (25 mmHg) | 3 | 184 (179) | 1.8 (1.1) | 39.8 (38.9)°C | 13% |
| Keiser34* | 38°C | 30% (15 mmHg) | 3 | 183 (182) | 1.4 (0.8) | 39.7 (39.2)°C | 13% |
| Keiser34 ** | 38°C | 30% (15 mmHg) | 3 | 186 (177) | 1.7 (0.8) | 39.6 (38.8)°C | 7% |
| Périard12 | 35°C | 60% (25 mmHg) | 4 | 183( 182) | 2.3 (1.3) | 39.4 (38.6)°C | 18% |
| Périard73 | 35°C | 60% (25 mmHg) | 4 | 183( 180) | 2.4 (1.8) | 39.6 (38.8)°C | 13% |
| Périard74 | 35°C | 60% (25 mmHg) | 3 | 178 (178) | 2.1 (1.3) | 39.8 (39.0)°C | 13% |
| Roelands35 | 30°C | 55% (17 mmHg) | 0.5 | 180 (176) | — | — | 11% |
| Roelands36 | 30°C | 55% (17 mmHg) | 0.5 | 180 (184) | 1.9 (1.6) | 39.3 (39.0)°C | 25% |
| Watson37 | 30°C | 55% (17 mmHg) | 0.5 | — | 1.8 (1.4) | 39.7 (39.2)°C | 23% |
| VanHaitsma75 | 35°C | 25 (11 mmHg) | 0.5 | 175 (175) | — | 39.2 (38.8)°C | 16% |
| Schlader76 | 40°C | 14 (8 mmHg) | 1.5 | 183 (176) | 1.4 (1.0) | 38.7 (38.5)°C | 22% |
| Peiffer38 | 32°C | 40 (14 mmHg) | 8.9 | 172 (168) | — | 39.5 (39.1)°C | 6% |
| Romer77 | 35°C | 30 (13 mmHg) | 0.5 | — | — | — | 18% |
Signifies studies with values reported pre-acclimatization (and post acclimatization in the same study marked with **) while subjects in the remaining studies were considered either acclimatized or familiarized with the exercise set-up in the heat prior to testing. Data that wasn't directly extractable was obtained via personal communication with authors or estimated on the basis of provided data (when possible) – ”-” indicates that the present value was not reported or possible to estimate/obtain. Columns from left to right: name of lead author and article publication year, temperature in the hot time trial in degrees Celsius, relative humidity and absolute air vapor pressure in the hot time trial, wind speed in meters pr. second (which was set at 0.5 m/s if the time trial was indoor stationary ergometer cycling without artificial airflow generation), highest heart rate in beats per minute observed during the hot and control trials, sweat rate during the hot and controls in liters per minute either directly measured or calculated from body weight changes, core temperature in the hot and control trial at time trial completion in degrees Celsius and percentage power output reduction in the hot trial compared to the control.