Purpose. Whilst evidence supports beneficial effects of exercise on heart rate variability in cancer patients, its impact on heart rate recovery (HRR) and possible ...
Support Care Cancer (2015) 23:3513–3520 DOI 10.1007/s00520-015-2719-4
ORIGINAL ARTICLE
Heart rate recovery and aerobic endurance capacity in cancer survivors: interdependence and exercise-induced improvements Daniel Niederer 1 & Lutz Vogt 1 & Javier Gonzalez-Rivera 1 & Katharina Schmidt 1 & Winfried Banzer 1
Received: 19 December 2014 / Accepted: 23 March 2015 / Published online: 3 April 2015 # Springer-Verlag Berlin Heidelberg 2015
Abstract Purpose Whilst evidence supports beneficial effects of exercise on heart rate variability in cancer patients, its impact on heart rate recovery (HRR) and possible associations of exercise capacity and HRR have not yet been investigated. We aimed to evaluate the effects of an exercise intervention on HRR in relation to the baseline aerobic capacity. Methods Cancer patients (n=309, 178 females) performed a cardiopulmonary exercise test at baseline and at a 4-month interval follow-up with home-based and supervised exercise programs in-between. VO2 and heart rate were assessed during and HRR at 60 and 120 s after test termination. Based on a median split of the VO2 peak baseline values, participants were dichotomized into two groups: below median (47 female; 57.5±10 years) and above median (48 female; 54.3± 12 years). Results In the baseline sample (n=309), VO2 peak correlated significantly with HRR60 (r = .327, p < .01) and HRR120 (r=.524, p.05). Complier only During the 16-week intervention period, patients were active (supervised and individual; hiking, walking, running, bicycle and swimming) 3–6 (4.0±1.0) times per week for 60–300 min (185±82) at 60–100 % of individual anaerobic threshold and at RPE scores of 12–15. Complying participants were divided into two groups following the median split based on VO2 peak Table 1 Baseline characteristics for all patients included into the study (n=309)
Mean±SD 95 % CI
HRmax [bpm]
VO2 peak [ml/kg/min]
CRF [a.u.]
QoL [a.u.]
156±20.6 153.6–159
21.7±5.6 21.1–22.4
45.5±25.8 42.4–48.6
59.1±19.6 56.7–61.4
SD standard deviation, CI confidence interval, n numbers, HR heart rate, CRF cancer-related fatigue, QoL quality of life, bpm beats per minute, a.u. arbitrary units
Our findings point toward a positive linear relationship between actual aerobic capacity and heart rate recovery in cancer patients. Results also suggest that autonomic cardiac regulation capacity of patients with initial VO2 peak values below median benefit the most from the intervention. Enhancements of the HRR might occur coincidentally to VO 2 peak improvements. Associations of baseline HRR and VO2 peak The present finding of a linear relationship between HRR and VO2 is in accordance with recent research, stating such an association in healthy subjects [22]. Thus, the suggested interdependence of aerobic capacity and HRR is supported by other authors’ findings, stating an association of cardiorespiratory fitness and general ANS function [23]. In a recently published study, the authors propose cut-off values to distinguish symptomatic from asymptomatic HRR values [24]. The authors suggest an HRR60 underneath 21 bpm to be symptomatic. Other authors published a cutoff of 27 bpm for HRR60 [25]. They proposed that values below this cut-off are to be seen as a mortality predictor. Our participants’ mean value is below these two cut-offs and might therefore be interpreted as symptomatic. Following exhaustion after exercise, the initial HRR is mostly dependent on parasympathetic reactivation. The later decrease in heart rate is seen to be attributed to continued parasympathetic reactivation and sympathetic withdrawal, what was recently described as the chronic systemic stress syndrome [26]. Thus, HRR following exercise, together with the capacity of the cardiovascular system to reverse autonomic nervous system and baroreceptor adaptations, is commonly described as vagal reactivation [27]. Attenuated HRR as a marker of reduced parasympathetic activity has been demonstrated to be an independent predictor of cardiac mortality [28] and all-cause mortality [29–31]. The predictive value of HRR parameters was consistently shown in various systemic disorders [32, 26]. Because of the association of improved vagal
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Fig. 2 Results of the baseline values’ correlation analyses of the total sample included into the trial. Correlation coefficients, indicated regression curves and their confidence intervals are displayed within figure. HRR heart rate recovery at 60 or 120 s following cardiopulmonary exercise testing (CPET) termination, bpm beats per minute, **p
