Effects of Home‐Based Exercise Training on Post‐Exercise Peripheral Muscle Oxygenation in Children with Congenital Heart Disease

Abstract

A hallmark feature of children with congenital heart disease (CHD) is exercise intolerance, along with slow post‐exercise muscle oxygenation recovery. Exercise rehabilitation programs have been shown to improve peak V̇O2 in children with CHD; however, exercise tolerance is still limited compared to healthy matched controls. Whether exercise training improves post‐exercise recovery of muscle oxygenation (as measured by tissue oxygenation index, TOI) in children with CHD compared to healthy children is unknown.PURPOSETo determine whether a 12‐week home‐based exercise intervention can improve post‐exercise TOI response after peak exercise in children with CHD compared to controls.METHODSEight children with CHD (f/m = 4/4; mean ± SD age: 12 ± 2 yrs) with simple and complex lesions and seven healthy controls (f/m = 3/4; age: 12 ± 3 yrs) were studied. Children with CHD completed a home‐based exercise program 3 times/week for 12 weeks, in addition to 6 biweekly in‐person sessions. Exercise tolerance was assessed with peak V̇O2 testing to volitional fatigue on a cycle ergometer, followed by 4 minutes of 20‐W recovery. Vastus lateralis TOI was continuously sampled during exercise and recovery via near‐infrared spectroscopy. Post‐exercise TOI recovery data was normalized from 0% (end‐exercise) to 100% (4 min post‐exercise) and data analyzed at set time points to characterize TOI time course changes (0s, 15s, 30s, 60s, 90s, 120s, 180s and 240s). Pre vs. post training changes in TOI were analyzed using paired t‐tests. Significance was accepted when P<0.05.RESULTSPost‐exercise TOI was significantly lower in CHD pre‐training compared to controls at 15s (9 ± 9 vs. 27 ± 16 %; P = 0.018) and 30s (32 ± 17 vs. 72 ± 35%; P = 0.012). Similarly, post‐exercise TOI in CHD after exercise training was significantly lower than controls at 15s (9 ± 7 vs. 27 ± 16 %; P = 0.014) and 30s (36 ± 22 vs. 72 ± 35%; P = 0.030)‐‐‐.CONCLUSIONExcessive post‐exercise impairment in TOI recovery persists after home‐based exercise in children with CHD compared to controls.This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.