Table 3

 Predicted percentage body mass loss due to dehydration at the end of a 42 km marathon held in warm (28°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.
50400−1.2−1.9−2.6 −3.2
6000.8−0.2−1.3−2.0
8002.71.50.1−0.9
70400−2.5−2.9 −3.5 −3.9
600−1.0−1.7−2.5 −3.1
8000.4−0.5−1.6−2.3
90400 −3.1 −3.5 −4.0 −4.3
600−2.0−2.6 −3.2 −3.6
800−0.9−1.7−2.5 −3.0