Intrahospital weight and aerobic training in children with cystic fibrosis: A randomized controlled trial

PURPOSE: The purpose of our study was to assess the effects of an 8-wk intrahospital combined circuit weight and aerobic training program performed by children with cystic fibrosis (of low-moderate severity and stable clinical condition) on the following outcomes: cardiorespiratory fitness (V̇O 2peak) and muscle strength (five-repetition maximum (5RM) bench press, 5RM leg press, and 5RM seated row) (primary outcomes) and pulmonary function (forced vital capacity, forced expiratory volume in 1 s), weight, body composition, functional mobility (Timed Up and Down Stairs and 3-m Timed Up and Go tests), and quality of life (secondary outcomes). We also determined the effects of a detraining period (4 wk) on the aforementioned outcomes. METHODS: We performed a randomized controlled trial design. Eleven participants in each group (controls: 7 boys, age = 11 ± 3 yr, body mass index = 17.2 ± 0.8 kg•m -2 (mean ± SEM); intervention: 6 boys, age = 10 ± 2 yr, body mass index = 18.4 ± 1.0 kg•m -2) started the study. RESULTS: Adherence to training averaged 95.1% ± 7.4%. We observed a significant group × time interaction effect (P = 0.036) for V̇O 2peak. In the intervention group, V̇O 2peak significantly increased with training by 3.9 mL•kg -1•min -1 (95% confidence interval = 1.8-6.1 mL•kg -1•min -1, P = 0.002), whereas it decreased during the detraining period (-3.4 mL -1•kg -1•min -1, 95% confidence interval =-5.7 to-1.7 mL -1•kg -1•min -1, P = 0.001). In contrast, no significant changes were observed during the study period within the control group. Although significant improvements were also observed after training for all 5RM strength tests (P < 0.001 for the interaction effect), the training improvements were not significantly decreased after the detraining period in the intervention group (all P > 0.1 for after training vs detraining). We found no significant training benefits in any of the secondary outcomes. CONCLUSIONS: A short-term combined circuit weight and aerobic training program performed in a hospital setting induces significant benefits in the cardiorespiratory fitness and muscle strength of children with cystic fibrosis.