Changes in the volume and circumference of the torso, leg and arm after cycling in the heat determined using 3D whole body scanners conference paper, Lugano, Switzerland,
Whole body volume changes due to sweat loss after exercise in the heat are well documented, but little is known about the relative contribution of the torso and extremities to these volume changes. It is the purpose of this study to quantify these effects. Therefore, seven healthy male subjects were scanned using a SizeStream and Vitronic whole body scanner prior to and shortly after they lost 1.7 0.1% of their body weight due to cycling at 2 W/kg in a 35degC, 20% relative humidity climatic chamber for 75 minutes. Whole body volume loss was 1.0 0.7% using the SizeStream scanner and 1.3 0.6% using the Vitronic scanner. Torso volume decreased most with 2.1 1.5% (p=0.009) and 5.6 3.1% (p=0.002) followed by the legs with 1.1 2.7% (N.S. and 2.9 1.0% (p<0.0001) for SizeStream and Vitronic respectively. Changes in arm volume were negligible. The circumference decreased significantly for the chest and upper legs but not for the waist and arms. We conclude that the major part of sweat loss originates from the torso and legs, but since both scanners did not produce similar results likely due to differences in accuracy, we recommend using high resolution scanners to record volume changes in more detail.