Sex differences in heart rate variability: a longitudinal study in international elite cross-country skiers

摘要: Exercise-related sudden cardiac deaths (SCD) occur with a striking male predominance. A higher sympathetic tone in men has been suggested as risk factor for SCD. Elite athletes have the highest exercise-related We aimed to analyze autonomic nervous system of elite cross-country skiers from Norway, Russia and Switzerland supine position after orthostatic challenge various training periods (TP). Measurements heart rate variability (HRV) were performed on weekly basis over 1 year using an test controlled breathing. Main outcome parameters high-frequency power (HFsupine) marker parasympathetic activity low-frequency/high-frequency ratio (LF/HFstand) activation. Training intensity duration recorded daily expressed strain. The year was divided into three TPs. An average HRV measurements calculated each TP. Female (n = 19, VO2max 62.0 ± 4.6 ml kg−1 min−1, age 25.8 ± 4.3 years) (n = 16, 74.3 ± 6.3 24.4 ± 4.2 years) included. strain comparable between sexes (all p > 0.05) changed TPs p < 0.05) while no time. There sex differences HFsupine LF/HFstand significantly all For amount training, showed constantly markers provocation maneuver. This may explain part predominance sports-related