Six Months of Exercise Training Improves Ventilatory Responses during Exercise in Adults with Well-Healed Burn Injuries

Abstract

ABSTRACTIntroductionPulmonary function is lower after a severe burn injury, which could influence ventilatory responses during exercise. It is unclear whether exercise training improves pulmonary function or ventilatory responses during exercise in adults with well-healed burn injuries. Therefore, we tested the hypothesis that exercise training improves pulmonary function and ventilatory responses during exercise in adults with well-healed burn injuries.MethodsThirty-nine adults (28 with well-healed burn injuries and 11 non–burn-injured controls) completed 6 months of unsupervised, progressive exercise training including endurance, resistance, and high-intensity interval components. Before and after exercise training, we performed comprehensive pulmonary function testing and measured ventilatory responses during cycling exercise. We compared variables using two-way ANOVA (group–time; i.e., preexercise/postexercise training (repeated factor)).ResultsExercise training did not increase percent predicted spirometry, lung diffusing capacity, or airway resistance measures (time:P≥ 0.14 for all variables). However, exercise training reduced minute ventilation (V̇E; time:P≤ 0.05 for 50 and 75 W) and the ventilatory equivalent for oxygen (V̇E/V̇O2; time:P< 0.001 for 75 W) during fixed-load exercise for both groups. The ventilatory equivalent for carbon dioxide (V̇E/V̇CO2) during exercise at 75 W was reduced after exercise training (time:P= 0.04). The percentage of age-predicted maximum heart rate at the ventilatory threshold was lower in adults with well-healed burn injuries before (P= 0.002), but not after (P= 0.22), exercise training. Lastly, exercise training increasedV̇Eand reducedV̇E/V̇O2during maximal exercise (time:P= 0.005 for both variables).ConclusionsThese novel findings demonstrate that exercise training can improve ventilatory responses during exercise in adults with well-healed burn injuries.