Re: Effects of resistance training with/without photobiomodulation on muscle and respiratory function in difficult-to-control asthma: a randomized trial.
This letter discusses Costa et al.'s randomized trial of resistance training (RT) combined with photobiomodulation therapy (PBMT) for difficult-to-control asthma (DTCA). The triple-blind study shows RT+PBMT safely improves peripheral muscle strength and exercise capacity better than RT alone. PBMT has dose-dependent effects, but optimal parameters for chronic respiratory patients remain unclear. Some clinicians have proposed standalone PBMT for DTCA patients unable to complete resistance training, but this approach has not been validated in clinical trials. The absence of a PBMT-only group limits assessment for patients unable to tolerate RT. The intervention did not improve lung function or asthma control, acting only peripherally. RT+PBMT is a useful adjuvant therapy; future studies should optimize PBMT dosing, test standalone PBMT, and examine long-term outcomes, and compare different PBMT wavelengths, energy settings and irradiation sites to refine real-world treatment protocols.