Heart rate response and parasympathetic modulation during recovery from exercise in boys and men

Abstract

The purpose of this study was to examine the influence of postexercise parasympathetic modulation, measured by heart rate variability (HRV), on heart rate recovery (HRR) in boys (n = 13, 10.1 ± 0.8 years) and men (n = 13, 23.9 ± 1.5 years) following maximal and submaximal exercise. Subjects completed 10 min of supine rest, followed by graded exercise on a cycle ergometer to maximal effort. On a separate day, subjects exercised at an intensity equivalent to ventilatory threshold. Immediately following both exercise bouts, 1-min HRR was assessed in the supine position. HRV was analyzed under controlled breathing during the final 5 min of rest and recovery in the time and frequency domains and transformed to natural log (ln) values. Boys had a greater 1-min HRR than men following maximal (58 ± 8 vs. 47 ± 11 beats·min(-1)) and submaximal (59 ± 8 vs. 47 ± 15 beats·min(-1)) exercise (p < 0.05). Following maximal exercise, boys had greater ln root mean square successive differences in R-R intervals (2.52 ± 0.95 ms), ln standard deviation of NN intervals (3.34 ± 0.57 ms), ln high-frequency power (4.32 ± 2.00 ms(2)), and ln low-frequency power (4.98 ± 1.17 ms(2)) than men (1.33 ± 0.37 ms, 2.52 ± 0.24 ms, 1.32 ± 1.06 ms(2) and 2.80 ± 0.74 ms(2), respectively) (p < 0.05). There were no differences in any HRV variables between groups following submaximal exercise (p > 0.05). In conclusion, it appears that greater parasympathetic modulation accounts for greater HRR following maximal exercise in boys versus men. Although submaximal HRR was greater in boys, parasympathetic responses were similar between groups.

Heart rate recovery and parasympathetic modulation in boys and girls following maximal and submaximal exercise

“…The present study used a relatively narrow age range and the maturational statuses were relatively homogenous (all pre-pubertal except for one girl). It is known that HRR is affected by age and maturation, which could explain the differences between the studies (Baraldi et al 1991;Buchheit et al 2011;Guilkey et al 2014;Ohuchi et al 2000). HRR also was similar between boys and girls following submaximal exercise at VT (~60 % VO 2max ).…”

“…The criteria used were as follows: (1) failure to maintain a pedal rate >50 rpm; (2) respiratory exchange ratio (RER) ≥1.00; (3) OMNI RPE scale ≥8 and (4) peak HR at the termination of test ≥95 % of age predicted maximal (208 − 0.7 × age). If two of the four criteria were met, maximal exercise was considered to have been achieved (Guilkey et al 2014;Rogowski et al 2012). Within 30 s, following the conclusion of the graded exercise test, participants assumed a supine position on an examination table.…”

“…Additionally, 13 boys who participated in a previous study (Guilkey et al 2014) were included for comparison purposes. All children who participated were apparently healthy and recreationally active, but not well trained, based on their responses on a health history questionnaire.…”

“…The results of the three investigators were pooled and the coefficient of variation between the values was determined. If the coefficient of variation was less than 5 %, all three values were averaged; if the coefficient of variation was greater than 5 %, the two closest values were averaged (Anderson and Mahon 2007;Guilkey et al 2014). …”

“…Participants adhered to a breathing frequency of 15 breaths per minute (0.25 Hz) for the entire resting period and the final 6 min of each recovery period to control for respiratory sinus arrhythmia (Fleming et al 2011;Guilkey et al 2014). The final 5 min of the electrocardiogram recording during the resting and recovery periods were used for the HRV analysis, in order to ensure stationarity of the signal (Camm et al 1996).…”