Heart rate variability and stress perception: The influence of physical fitness

Aims. - The autonomic nervous system (ANS) is somewhat linked to perceived stress. This relationship may be modulated by the individual's training status. The aim was to assess whether heart rate variability (HRV) and perceived stress were interrelated in healthy subjects with various levels of training status. Methods. - One hundred and seventeen healthy participants (mean age 20 +/- 3 yrs) were divided into 3 groups according to their training status: power-trained athletes (n = 43), endurance-trained athletes (n = 36), and untrained volunteers (n = 38). The perception of stress was measured using the perceived stress scale questionnaire, heart rate (HR) was recorded at rest, and HRV analyses were made in time and frequency domain using the Kubios application. Results. - Endurance-trained athletes showed higher levels of HRV compared to untrained and, to a lesser extent, to power athletes. HRV parameters of untrained subjects perceiving less stress did not differ from those of endurance-trained athletes who also perceived less stress. Power-trained athletes who perceived less stress had higher values of SD1, RMSSD, HF, and log HF (P < 0.05, P < 0.05, P < 0.01; P < 0.05 respectively) compared to those who perceived more stress. Our data indicate that training status modulates HRV, and that changes in perceived stress are associated with changes in HRV. Power-trained athletes who perceived less stress had greater HRV compared to athletes who perceived more stress. Conclusion. - These results may be important in terms of understanding ANS modulation and stress perception for better managements of stress and/or training/recovery processes in athletes with various training status. (C) 2021 Elsevier Masson SAS. All rights reserved.