Effect of a 48-Week Aerobic Training Program On Heart Rate Recovery In Stage 3 CKD Patients

INTRODUCTION: Heart rate recovery (HRR) is a non-invasive method of determining cardiovascular risk. Typically, cardiovascular prognosis is favorable when the difference in peak heart rate and heart rate at the first minute of recovery (HRR1) following a graded exercise test (GXT) is greater than 12 beats. When (HRR1) is less than 12 beats, the cardiovascular prognosis is thought to be unfavorable. The ability of the heart to normalize itself following strenuous activity is a function of increased parasympathetic tone. There has been little research on the effects of aerobic training on HRR in CKD patients. PURPOSE: Therefore the current study was designed to assess the effect of a 48- week aerobic training intervention on HRR in stage 2-4 CKD patients. METHODS: Twenty-one stage 2-4 CKD patients (54.9 ± 11.1 yr, eGFR 41.2 ± 22.7 ml/min/1.73m) were matched at baseline (BL) and randomly assigned to a treatment (TG; n=10), or control (CG; n=11) group. At BL, a stress test was completed by all subjects before being randomized into either the CG or TG. Immediately following the BL, post 24 week and post 48-week stress tests, subjects were seated to measure their HRR 1-minute following their VO2 peak. Subjects in the TG were expected to attend three supervised training sessions per week for 48 weeks with each session lasting between 20-55 minutes. Subjects in the CG were advised to follow the advice of their nephrologist and go about their daily lives with no exercise intervention. RESULTS: Differences in HRR1 and two minute heart rate recovery (HRR2) between the treatment and control groups were examined at 24 and 48 weeks. ANCOVA analyses, using the baseline differences between peak heart rate during VO 2 peak and heart rate during recovery as the covariate, revealed a significant difference between treatment and control groups for HRR1 at 48 weeks, M treatment = 18.12 (7.57), M control = 11.00 (6.02), F 1,16 = 4.58, p <.05. Differences between treatment and control at 48 weeks for HRR2 were not significant, and differences for HRR1 and HRR2 at 24 weeks were also not significant. CONCLUSIONS: Based upon our data, the 48 week training program seemed to favorably alter autonomic regulation in this sample of CKD patients indicating a reduction in cardiovascular risk in this population.