Colour graphics interpretation of AT and /WR slope. This graphic shows the gradual change from high risk (red) to low risk (green) via an area of caution (yellow). It plots the AT and the /WR slope. This minimizes the assumption that an AT of 10.9 ml.min−1.kg−1 is very different from an AT of 11.1 ml.min−1.kg−1 (see text). Reproduced with permission from Cortex Biophysik GmbH.