Physiological instrumentation and measurements
HEART
Body mass (kg) and height (cm) were measured using a scale (Sauter, Balingen, Germany) and a stadiometer (Holtain Limited, Seritex, Wales, UK). Urine specific gravity was measured using a refractometer (Atago, Tokyo, Japan). Heart rate (bpm) and an estimate of arterial blood oxygen-haemoglobin saturation (S