Photobiomodulation and Physical Exercise, Impacts on Wrist Muscle Strength and Endurance: A Blinded Randomized Trial

To investigate the effects of photobiomodulation (PBM) at two wavelengths, 850 nm and 660 nm, on the maximum strength and local muscular endurance of the flexor and extensor muscles of the wrist and forearm. This was a ran-domized, single-blind clinical trial with 75 healthy participants (18–30 years old), divided into five groups: placebo, exercise, exercise + placebo, isolated photobiomodulation, and photobiomodulation + exercise. The interventions took place over 12 sessions, with assessments on days 1, 7, and 12. Maximum strength was measured by dynamom-etry and endurance by sustained time in isometry. There was no significant effect of the intervention on maximum strength (p = .058), but there was an effect of the moment (p < .001) and the intervention * moment interaction (p = .014). For muscular endurance, there was only an effect of time (p < .001). Photobiomodulation alone seems to have optimized muscle strength, but none of the forms tested had an effect on endurance. Cite this article as: Fonseca, P. M. C., de Oliveira, L. G., Buzanello, M. R., de Carvalho, A. R., & Bertolini, G. R. F. (2026). Photobiomodulation and physical exercise, impacts on wrist muscle strength and endurance: a blinded randomized trial. Research in Sports Science, 16, 0052, doi:10.5152/rss.2026.25052.