Effects of a Short-Term Resistance-Training Program on Heart Rate Variability in Children With Cystic Fibrosis—A Randomized Controlled Trial

Abstract

Background: Cystic fibrosis (CF) affects the autonomic nervous system (ANS) and exercise in healthy children modulates the interaction between sympathetic and parasympathetic activity. This study aimed to evaluate the effects of a short-term resistance exercise program on heart rate variability (HRV) in children and adolescents with CF.Methods: A randomized controlled trial was carried out in children diagnosed with CF aged 6–18 years. Individuals were divided into two groups: control (CON) and resistance-training (EX). Individuals in the EX group completed an individualized guided resistance program (5-RM—60–80%) for 8 weeks (3 sessions of 60 min/week). Upper and lower limbs exercises (seated bench press, seated lateral row, and leg press) were used. HRV was measured using a Suunto watch with subjects in lying position.Results: Nineteen subjects (13 boys) were included (CON = 11; and EX = 8). Mean age was 12.2 ± 3.3, FEV1 (forced expiratory volume in the first second) z-score was 1.72 ± 1.54 and peak oxygen consumption (VO2peak) 42.7 ± 7.4 mL.Kg–1.min–1. Exercise induced significant changes in the frequency-domain variables, including a decrease in LF power (p = 0.001, d = 0.98) and LF/HF ratio (p = 0.020, d = 0.92), and an increase in HF power (p = 0.001, d = −0.97), compared to the CON group. No significant changes were found for time-domain variables, although increases with a moderate effect size were seen for SDNN (p = 0.152, d = −0.41) and RMSSD (p = 0.059, d = −0.49) compared to the CON group.Conclusion: A short-term resistance exercise-training program was able to modulate HRV in children and adolescents with CF presenting mild to moderate lung function impairment and good physical condition.Clinical Trial Registration:www.ClinicalTrials.gov, identifier NCT04293926.

Effects of a Long-Term Wearable Activity Tracker-Based Exercise Intervention on Cardiac Morphology and Function of Patients with Cystic Fibrosis

“…Additionally, chronotropic incompetence is crucial in limiting exercise in patients with CF [24]. Finally, it was described that cardiac ANS could be altered in CF, causing heart rate variability (HRV) abnormalities [25]. The echocardiographic findings of our patients showed no underlying LV systolic and diastolic and RV systolic function abnormalities, except for marginal results of RV systolic function.…”

“…However, it remains unknown if the exact beneficial mechanisms of exercise also apply to LV dysfunction in CF patients. Interestingly, the study of Estévez-González et al has shown that an 8-week resistance-training program improved the sympathovagal balance, leading to an increase in HRV [25].…”

Physical function, body mass index, and fitness outcomes in children, adolescents, and emerging adults with craniopharyngioma from proton therapy through five years of follow-up

“…Data from multiple studies (males, N sizes ranging from 2104 to 803,505) indicate that a one SD higher systolic BP in adolescence increases risk for ischemic stroke (Hazard Ratio [HR], 1.04; 95% CI 1.02–1.07) and hemorrhagic stroke (HR, 1.12; 95% CI 1.07–1.17) in adulthood [ 38 ], that both elevated systolic and diastolic BPs in adolescence increase risk for cardiovascular mortality in adulthood [ 39 ], and that elevated resting HR in adolescence is associated with heart failure, dilated cardiomyopathy [ 40 ], and cardiovascular and all-cause mortality [ 41 ]. Fortunately, interventions to address strength deficits improve markers of vascular flow in lean children [ 42 ], measures of glycemic control in children with insulin resistance [ 43 ], function in children with cerebral palsy, [ 44 ] frequency domain components of HR variability in children with cystic fibrosis [ 45 ], and both skeletal muscle mass and visceral adiposity in children and adolescents with obesity [ 46 ]. Interventions to promote weight loss such as diet, medications, and resistance and aerobic training, are also beneficial in pediatric populations [ 47 ].…”

Heart rate variability, exercise capacity and levels of daily physical activity in children and adolescents with mild-to-moderate cystic fibrosis

“…Recent evidence has shown that a short-term exercise resistance training program was effective in modulating HRV in children and adolescents with CF. 37 …”

“…In children and adolescents with CF presenting mild-to-moderate lung function impairment and a good physical state, 57.9% of individuals presented at least one altered HRV variable. 37 Based on the study by Gasior et al. , 21 which defines the normalization of HRV indices for school-aged children, we have used the SDNN vagal modulation index of the sample at rest to show that individuals with altered SDNN had worse lung function (FEV 1 and FVC) and less exercise capacity (distance covered in absolute and percentual values).…”