Free Flight Physiology: Paragliding and the Study of Extreme Altitude.

Abstract

Aims We sought to describe the physiological demands and the impact of environmental stressors of paragliding, a popular and evolving form of free flight, at moderate and extreme altitudes. We recorded oxygen consumption (VO2), heart rate (HR), respiratory frequency (fR), tidal volume (VT), oxygen saturation, accelerometry (G) and altitude in eight male pilots: 9.3 hours of flight at moderate altitudes (to 3,073 m, n=4), 19.3 hours at extreme altitude (to 7,458 m, n=2) and during high-G manoeuvers (n=2). We also analysed heart rate data from 17 male pilots (138 hours). Results Overall energy expenditure at moderate altitude was low (1.7 (0.6) metabolic equivalents) but physiological parameters were notably higher during take-off (p < 0.05). Pilots transiently reached ~7 G during manoeuvres. Mean HR at extreme altitude (112 (14) bpm) were elevated compared to moderate altitude (98 (15) bpm, p = 0.048). While VT were similar (p = 0.958), elevation in fR at extreme compared to moderate altitude approached significance (p = 0.058). Conclusions Physical exertion in paragliding appears low, so any subjective fatigue felt by pilots is likely to be cognitive or environmental. Future research should focus on reducing mental workload, enhancing cognitive function and improving environmental protection.