Sports-medical studies on parachute jumpers with particular reference to the behavior of heart rate.

The aim of the experiment was to record the heart rate tracings of three groups of parachutists - with manually operated parachutes, automatically operated parachutes and formation parachutists (sky divers) - during the jump and to compare these with the findings obtained during bicycle ergometer stress tests. A total of 112 parachute jumps involving 31 subjects were evaluated. All the subjects exhibited a significant increase in heart rate during the exit, canopy opening and landing phases. Qualitatively, the heart rate curves of the formation, manual and automatic parachutists showed a similar trend. Rises in heart rate during the opening of the parachute (for the formation parachutists) and during landing (for the automatic parachutists) were, however, particularly pronounced. The increase in heart rate can be principally ascribed to emotional tension and a state of anticipation rather than to physical stress. The comparative evaluation of the ergometer tests showed that as a general rule stress factors in the submaximal region occur during parachuting, but that in extreme situations heart rates in the maximal region of physical stress may well be expected.