Supine and Standing Heart Rate Variability Responses to Training in Women's Soccer Players
Presentation given at the National Strength and Conditioning Association National Conference, Washington, D.C.
Heart rate variability (HRV) is a popular recovery status marker among sports teams. HRV is traditionally measured in the supine position, but the standing position provides a small physiological challenge that requires autonomic modulation of heat rate and vessel diameter to augment blood pressure and flow to adapt to the upright position. Thus, capturing HRV after standing upright may provide greater sensitivity to previous-day training, assuming that an unrecovered athlete will display a more prolonged or exaggerated stress response to standing. PURPOSE: To assess supine and standing HRV responses to standardized offseason training in collegiate women’s soccer players. A secondary aim was to assess within-subjects correlations between supine and standing measures. METHODS: A women’s soccer team (n = 12, age = 22 ± 2 years; height = 165 ± 6 cm; weight = 61 ± 6 kg) participated in this study. Throughout four non-consecutive weeks throughout the offseason, players performed resistance training, soccer practice, and cardiorespiratory conditioning on Mondays and Thursdays. Soccer practices only were also held on Wednesdays and Fridays. Players recorded ultra-short, natural logarithm of the root mean square of successive R-R intervals multiplied by twenty, LnRMSSD) in the supine and standing position, daily after waking with a validated mobile device. Training load from each session was quantified via the session rating of perceived exertion method (sRPE). Linear mixed models and Cohen’s effect sizes were used to assess variation in outcome variables. Pearson’s correlations were used to quantify within-subjects relationships between supine and standing LnRMSSD. RESULTS: The sRPE from Mondays and Thursdays was greater than Wednesdays and Fridays (p < 0.05, ES = 2.95 – 3.25). Standing LnRMSSD on Mondays was greater than Tuesdays and Fridays (p < 0.05, ES = 0.48 – 0.52). No main effect was observed for supine LnRMSSD (p = 0.10, ES = 0.10 – 0.49). Mean ± 95% confidence interval for supine and standing LnRMSSD and sRPE are displayed in Figure 1. Within-subjects correlations between supine and standing LnRMSSD ranged from r = -0.165 – 0.625, with statistical significance (p < 0.05) achieved for only 4 players. CONCLUSIONS: Significant decrements in standing, but not supine LnRMSSD were observed following days with the greatest training load. Supine LnRMSSD measures were not consistent predictors of standing measures. PRACTICAL APPLICATIONS: When monitoring HRV for the purpose of assessing responses to previous-day training, standing measures may be preferred over supine measures. Practitioners should be aware that supine and standing measures do not show consistent relationships and therefore should not be used interchangeably.
National Strength and Conditioning Association National Conference
Oddi, Brian, Mark A. Christiani, Andrew A. Flatt.
"Supine and Standing Heart Rate Variability Responses to Training in Women's Soccer Players."
Health and Kinesiology Faculty Presentations.