Parkinson's disease, aerobic exercise and photobiomodulation: a randomised controlled trial

Although Parkinson's disease (PD) is the neurological disease with the fastest growing prevalence, no disease-modifying treatments are yet available. However, regular exercise and photobiomodulation (PBM) with near-infrared light represent potential curative approaches. We hypothesized that combining those approaches may result in synergistic benefits. In the present randomized clinical trial, seventy-two people with PD were assigned to one of four conditions: six months of aerobic exercise (Exercise), PBM (808 nm), a combination of both (Exercise + PBM) or control. Motor symptoms (MDS-UPDRS), ten-meter walking test (TMWT), timed up and go test (TUG) and posturographic parameters were primary outcomes. The data of fifty-three subjects were evaluated using ANOVAs and non-parametric statistics. We observed positive effects especially of Exercise on MDS-UPDRS and TMWT, only of PBM on posturography outcomes and no effects in handgrip strength or disability of the upper extremities in any groups. No additive or synergistic effects for any of the measured outcomes were observed when the exercise intervention and the PBM intervention were combined. Although both exercise and PBM improved distinct deficits in PD, for an effective utilization of both approaches, a better understanding of the mode of action and especially the determination of individual stress responses, recovery requirements and thresholds to damage for photobiomodulation alone and the combination with exercise are necessary. CT ID: NCT05152706.