Scott Michael1, Ollie Jay2, Kenneth S Graham3, Glen M Davis2. 1. Discipline of Exercise and Sports Science, Faculty of Health Sciences, The University of Sydney, C103, Cumberland Campus, PO Box 170, Lidcombe, NSW, 1825, Australia. scott.michael@sydney.edu.au. 2. Discipline of Exercise and Sports Science, Faculty of Health Sciences, The University of Sydney, C103, Cumberland Campus, PO Box 170, Lidcombe, NSW, 1825, Australia. 3. New South Wales Institute of Sport, Sydney Olympic Park, NSW, 2127, Australia.
Abstract
PURPOSE: This study investigated non-invasive indices of post-exercise parasympathetic reactivation (using heart rate variability, HRV) and sympathetic withdrawal (using systolic time intervals, STI) following different exercise durations. METHODS: 13 healthy males (age 26.4 ± 4.7 years) cycled at 70% heart rate (HR) reserve for two durations-8 min (SHORT) and 32 min (LONG)-on separate occasions: HRV (including natural logarithm of root mean square of successive differences, Ln-RMSSD) and STI (including pre-ejection period, PEP) were assessed throughout 10 min seated recovery. RESULTS: Exercise HR was similar between SHORT and LONG (146 ± 7 and 147 ± 6 b min-1, respectively; p = 0.173), as was HR deceleration during 10 min recovery (p = 0.199). HR remained elevated above baseline (p < 0.001) throughout recovery for both trials (SHORT 82 ± 13 b min-1; LONG 86 ± 10 b min-1, at 10 min post-exercise). Ln-RMSSD was similar at end-exercise between trials (SHORT 1.10 ± 0.30 ms; LONG 1.05 ± 0.73 ms; p = 0.656), though it recovered more rapidly following SHORT (p = 0.010), with differences apparent from 1 min (SHORT 2.29 ± 1.08 ms; LONG 1.85 ± 0.82 ms; p = 0.005) to 10 min post-exercise (SHORT 2.89 ± 0.80 ms; LONG 2.46 ± 0.70 ms; p = 0.007). Ln-RMSSD remained suppressed below baseline throughout recovery following both trials (p < 0.001). PEP was the same at end exercise for both trials (70 ± 6 ms), with exercise duration having no effect on recovery (p = 0.659). By 10 min post-exercise, PEP increased to 130 ± 21 ms (SHORT) and 131 ± 20 ms (LONG), which was similar to baseline (p ≥ 0.143). CONCLUSIONS: Prolonged exercise duration attenuated the recovery of HRV indices of parasympathetic reactivation, but did not influence STI indices of sympathetic withdrawal. Therefore, duration must be considered when investigating post-exercise HRV. Monitoring these measures simultaneously can provide insights not revealed by underlying HR or either measure alone.
PURPOSE: This study investigated non-invasive indices of post-exercise parasympathetic reactivation (using heart rate variability, HRV) and sympathetic withdrawal (using systolic time intervals, STI) following different exercise durations. METHODS: 13 healthy males (age 26.4 ± 4.7 years) cycled at 70% heart rate (HR) reserve for two durations-8 min (SHORT) and 32 min (LONG)-on separate occasions: HRV (including natural logarithm of root mean square of successive differences, Ln-RMSSD) and STI (including pre-ejection period, PEP) were assessed throughout 10 min seated recovery. RESULTS: Exercise HR was similar between SHORT and LONG (146 ± 7 and 147 ± 6 b min-1, respectively; p = 0.173), as was HR deceleration during 10 min recovery (p = 0.199). HR remained elevated above baseline (p < 0.001) throughout recovery for both trials (SHORT 82 ± 13 b min-1; LONG 86 ± 10 b min-1, at 10 min post-exercise). Ln-RMSSD was similar at end-exercise between trials (SHORT 1.10 ± 0.30 ms; LONG 1.05 ± 0.73 ms; p = 0.656), though it recovered more rapidly following SHORT (p = 0.010), with differences apparent from 1 min (SHORT 2.29 ± 1.08 ms; LONG 1.85 ± 0.82 ms; p = 0.005) to 10 min post-exercise (SHORT 2.89 ± 0.80 ms; LONG 2.46 ± 0.70 ms; p = 0.007). Ln-RMSSD remained suppressed below baseline throughout recovery following both trials (p < 0.001). PEP was the same at end exercise for both trials (70 ± 6 ms), with exercise duration having no effect on recovery (p = 0.659). By 10 min post-exercise, PEP increased to 130 ± 21 ms (SHORT) and 131 ± 20 ms (LONG), which was similar to baseline (p ≥ 0.143). CONCLUSIONS: Prolonged exercise duration attenuated the recovery of HRV indices of parasympathetic reactivation, but did not influence STI indices of sympathetic withdrawal. Therefore, duration must be considered when investigating post-exercise HRV. Monitoring these measures simultaneously can provide insights not revealed by underlying HR or either measure alone.
Authors: Lucas Raphael Bento Silva; Paulo Gentil; Camila Simões Seguro; Gabriela Teles de Oliveira; Maria Sebastiana Silva; Antônio Roberto Zamunér; Thomas Beltrame; Ana Cristina Silva Rebelo Journal: Front Endocrinol (Lausanne) Date: 2021-11-09 Impact factor: 5.555
Authors: Jordana Oliveira; Paulo Gentil; João Pedro Naves; Luiz Fernando Souza Filho; Lucas Silva; Antonio Roberto Zamunér; Claudio Andre de Lira; Ana Rebelo Journal: Int J Environ Res Public Health Date: 2022-10-08 Impact factor: 4.614