Table 2

 Predicted percentage body mass loss due to dehydration at end of 42 km marathon held in cool/temperate (18°C) weather for runners of various body mass drinking 400–800 ml/h while running at 8.5–15 km/h

Body mass (kg)Fluid intake (ml/h)8.5 km/h10 km/h12.5 km/h15 km/h
Underlined type illustrates overdrinking relative to sweating rate. Bold type illustrates sufficient dehydration to compromise performance.
50400−0.4−1.1−2.0−2.6
6001.60.6−0.6−1.5
8003.62.20.7−0.3
70400−1.8−2.3 −3.0 −3.4
600−0.4−1.1−2.0−2.6
8001.10.1−1.0−1.8
90400−2.6−3.0 −3.5 −3.9
600−1.5−2.1−2.8 −3.2
800−0.4−1.1−2.0−2.6