Effect of high-intensity training on peak oxygen uptake and muscular strength after lung transplantation: A randomized controlled trial

Abstract

Peak oxygen uptake (VO2peak) remains low after lung transplantation (LTx). We evaluated the effect of high-intensity interval training (HIIT) on VO2peak, muscular strength, health-related quality of life (HRQOL), pulmonary function, and physical function after LTx. In this randomized controlled trial, 54 participants were enrolled from 6 to 60 months after LTx. The HIIT group (n = 25) followed a supervised HIIT program, consisting of endurance and strength trainings 3 times a week for 20 weeks. The control group (n = 29) received usual care. The primary outcome was a change in VO2peak measured by cardiopulmonary exercise testing. The secondary outcomes were changes in 1-repetition maximum (1RM) for arm press and leg press, HRQOL (36-Item Short-Form Health Survey [SF-36]), pulmonary function (forced expiratory volume in 1 sec, diffusing capacity of the lungs for carbon monoxide), and physical function (1RM in handgrip, 15-sec stair run, and 30-sec chair stand). A total of 46 participants completed the study, including 23 of 25 in the intervention group. For the primary outcome, the intention-to-treat analysis revealed a non-significant between-group difference for change in VO2peak of 0.7 ml/(kg.min) (95% CI = ‒0.3, 1.8) (p = 0.17). The between-group differences for 1RM arm press and leg press and mental aspect of SF-36 were 4.9 kg (95% CI = ‒0.1, 9.9) (p = 0.05), 11.6 kg (95% CI = 0.1, 23.0) (p < 0.05), and 5.7 kg (95% CI = 0.9, 10.4) (p = 0.02), respectively. There were no between-group differences in pulmonary function or physical function. When excluding participants with an attendance of <70% (n = 16), the between-group difference for VO2peak was 1.2 ml/(kg.min) (95% CI = 0.1, 2.4) (p = 0.032). HIIT improved muscular strength and HRQOL but did not improve VO2peak more than usual care after LTx. However, with acceptable adherence, HIIT appears to have beneficial effects on VO2peak.