An examination of single day vs. multi-day heart rate variability and its relationship to heart rate recovery following maximal aerobic exercise in females
Emily Bechke, Brian Kliszczewicz, Cherilyn McLester, Mark D. Tillman, Michael R. Esco, Roxanna Lopez
Abstract
Abstract The purpose of this study was to examine the relationship of a single day measure of heart rate variability (HRV), and the averaged baseline measures of HRV to heart rate recovery (HRR) following maximal exercise. Thirty females (22.9 ± 3.2 years, 64.8 ± 8.4 kg) completed four visits (V1–V4), where a 10-min HRV was recorded. Upon completing the V4 recording, a treadmill graded exercise test (GXT) was performed, followed by a 5-min active cool down. HRV was assessed through time domain measures [natural log of root mean square of successive R–R differences (lnRMSSD) and standard deviation of normal to normal intervals (lnSDNN)] and natural log frequency domain measures [low frequency (lnLF) and high frequency (lnHF)]. Variables collected over V1–V4 were measured as; day of (DO) GXT, 3 day (AV3), and 4 day average (AV4). HRR was calculated as the maximal HR achieved minus the HR at: 30-s (HRR30), 1-min (HRR1), 2-min (HRR2), 3-min (HRR3), 4-min (HRR4) or 5-min (HRR5) of recovery. Pearson’s Product correlations revealed significant correlations ( P = < 0.05) between all HRV DO measures to each HRR measure and are presented in ranges: lnSDNN (r = 0.442–0.522), lnRMSSD (r = 0.458–0.514), lnLF (r = 0.368–0.469), lnHF (r = 0.422–0.493). For HRV AV3, lnRMSSD AV3 and HRR1 were positively correlated (r = 0.390, P = 0.033). Last, HRV AV4 showed positive relationships ( P = < 0.05) between lnRMSSD AV4 and HRR30 (r = 0.365, P = 0.048); and for HRR1 and lnSDNN AV4 (r = 0.400, P = 0.029), lnRMSSD AV4 (r = 0.442, P = 0.014), and lnHF AV4 ( r = 0.368, P = 0.045); and lnRMSSD AV4 and HRR3 (r = 0.381, P = 0.038). Within the current study HRV DO displayed the strongest correlations to HRR therefore, averaged resting HRV measures do not strengthen the prediction of cardiovascular recovery following a GXT in this population.