Relationship between performance, heart rate variability and clinical symptoms in elite football: A case study
Authors: Bourdillon Nicolas , Barriac David , Millet Grégoire 
Published: February 2023

Introduction
Matches and high-intensity training put important load on elite football players, which may result in performance decrease and physiological alterations (Meeusen et al., 2013).
Positive correlations between heart rate variability (HRV) athletic performance have been reported (Buchheit et al., 2012) but the measurements were not related to match performance. Studies investigating the relationship between HRV and in-match performance data are scarce and none identified typologies of fatigue (Schmitt et al., 2015).
This is a case study of one elite football player that showed a typical autonomic dysfunction corresponding to a fatigue state with associated clinical symptoms.
Methods
A male elite football player playing in French Ligue 1 and continental competitions recorded his beat-to-beat heart rate (Polar H10) during an orthostatic test (5 min supine followed by 5 min standing) systematically 2 days before every match during a series of 8 matches at the rate of 1 match/week. These recordings allowed the assessment of mean heart rate (HR), power spectrum in the low- and high-frequency bands (LF and HF). During each match a GNSS sensor (Vector S7, Catapult) allowed the recording of total distance, acceleration/deceleration above 2m/s. Moreover, the number of passes, passes to the final thirty meters and number of duels and duels won were quantified by video analysis.
Results
The player played the entirety of the 8 games mostly as a midfielder and sometimes as a left back. Heart rate in the supine position was inversely correlated to the number of passes and successful passes to final third (R = -0.67, p < 0.05) whilst LF in the standing position was correlated to the duels and duels won (R = 0.75, p < 0.05). In addition, log(HF) was correlated to the number of acceleration during the match whilst log(LF) was correlated with the total distance ran. The player displayed on several occasions a fatigue profile characterized by a parasympathetic hypertonia in the standing position, which ultimately resulted in the player fainting on the pitch.
Discussion/Conclusion
HRV during an orthostatic test two days before a match could be useful in identifying fatigue profiles associated with decreased performances and clinical symptoms. Such methods should be used on an entire season and entire squad to better characterize the fatigue profiles in elite football and may help better adapt training sessions.
References
Buchheit, M., Simpson, M. B., Al Haddad, H., Bourdon, P. C., & Mendez-Villanueva, A. (2012). Monitoring changes in physical performance with heart rate measures in young soccer players. European Jopurnal of Applied Physiology, 112, 711–723. https://doi.org/10.1007/s00421-011-2014-0
Meeusen, R., Duclos, M., Foster, C., Fry, A., Gleeson, M., Nieman, D., Raglin, J., Rietjens, G., Steinacker, J., & Urhausen, A. (2013). Prevention, diagnosis, and treatment of the overtraining syndrome: Joint consensus statement of the European College of Sport Science and the American College of Sports Medicine. Medicine & Science in Sports & Exercise, 45(1), 186–205. https://doi.org/10.1249/mss.0b013e318279a10a
Schmitt, L., Regnard, J., Parmentier, A. L., Mauny, F., Mourot, L., Coulmy, N., & Millet, G. P. (2015). Typology of “Fatigue” by heart rate variability analysis in elite nordic-skiers. International Journal of Sports Medicine, 36(12), 999–1007. https://doi.org/10.1055/s-0035-1548885