A drifting upwards of heart rate when exercise is performed at a constant work rate over a prolonged period or in a hot environment. The cardiovascular drift is associated with sweating and a redistribution of blood so that peripheral circulation is increased. Body fluids are lost, reducing the volume of blood returning to the heart causing a decrease in stroke volume (see Starling's law). The heart rate increases in an attempt to compensate for the lower stroke volume and maintain a constant cardiac output.
Subjects: Sports and Exercise Medicine.