Does respiratory muscle training improve respiratory function compared to sham training, no training, standard treatment or breathing exercises in children and adults with neuromuscular disease? A Cochrane Review summary with commentary.

Background: Progressive muscle weakness is a feature of neuromuscular diseases (NMDs), a heterogeneous group of conditions with variable onset, presentation and prognosis that affect both children and adults. Respiratory muscle weakness compromises respiratory function and may lead to respiratory failure.
Objective: To assess the effects of respiratory muscle training (RMT) in adults and children with NMD.
Methods: A Cochrane Review by Silva et al. was summarized with comments.
Results: Eleven studies involving 250 randomized participants with NMD were included. While the studies showed that RMT may lead to improvements in lung function and respiratory muscle strength in people with ALS and DMD, this was not a consistent finding. The evidence from all the included trials was of low or very low certainty.
Conclusions: There may be some improvement in lung capacity and respiratory muscle strength following RMT in some NMD. There appears to be no clinically meaningful effect of RMT on physical functioning and quality of life in ALS. The low certainty of the evidence means that the results need to be interpreted with caution.