Effects of 12-Week Home-based Resistance Training on Peripheral Muscle Oxygenation in Children With Congenital Heart Disease: A CHAMPS Study.

Abstract

A hallmark feature of children with congenital heart disease (CHD) is exercise intolerance. Whether a home-based resistance training intervention improves muscle oxygenation (as measured by tissue oxygenation index, TOI) and exercise tolerance (O2 reserve) during aerobic exercise in children with CHD compared with healthy children is unknown. We report findings for 10 children with CHD (female/male: 4/6; mean ± standard deviation age: 13 ± 1 years) and 9 healthy controls (female/male: 5/4; age: 12 ± 3 years). Children with CHD completed a 12-week home-based exercise programme in addition to 6 in-person sessions. Exercise tolerance was assessed with a peak exercise test. Vastus lateralis TOI was continuously sampled during the peak O2 test via near-infrared spectroscopy. There was a medium effect (Cohen's d= 0.67) of exercise training on lowering TOI at peak exercise (pre: 30 ± 16 %total labile signal vs post: 20 ± 13 % total labile signal; P= 0.099). Exercise training had a small effect (Cohen's d= 0.23) on increasing O2 reserve by 1.6 mL/kg/min (pre: 27.2 ± 5.7 mL/kg/min vs post: 29.4 ± 8.8 mL/kg/min; P= 0.382). There was also a small effect (Cohen's d= 0.27) of exercise on peak heart rate (pre: 175 ± 23 beats/min vs post: 169 ± 21 beats/min; P= 0.18). TOI, O2 reserve, and heart rate were generally lower than healthy control participants. Our findings indicate that home-based resistance training may enhance skeletal muscle oxygen extraction (lower TOI) and subsequently O2 reserve in children with CHD.