Assessing pilot workload. Why measure heart rate, HRV and respiration?

The application of heart rate and respiratory measures to the human factors of flight is discussed. The concept of pilot workload is related to the concept of arousal and distinguished from physical workload. Finds from studies of pilot workload using heart rate measures are reviewed for flight, simulated flight and related real-life challenges. Measurement techniques and transducers are discussed from the perspective of field measurement. Recommended procedures are presented as are directions for future work.