Heart Rate Variability in Military Pilots During Flight: A Scoping Review.

This article systematically reviews studies on the influence of flight on autonomic modulation in military pilots, assessed through heart rate variability (HRV) indices across time, frequency, and nonlinear domains. The review found that real and simulated flights induce significant autonomic nervous system changes, typically characterized by increased sympathetic activity and decreased parasympathetic activity, reflecting heightened pilot workload and stress. Key HRV indices sensitive to workload variations during real flights include root mean square of successive differences (RMSSD), standard deviation of interbeat intervals (SDNN), low-frequency to high-frequency power ratio (LF/HF), and Poincaré plot measures (SD1 and SD2). Recovery of autonomic function postflight varies depending on flight profile, duration, and individual factors, with some effects persisting for hours after landing. These findings highlight HRV as a valuable objective tool for monitoring pilot workload and suggest further research to optimize training and recovery protocols.