Therapeutic Ultrasound for Muscle Recovery After Muscle Fatigue Exercise

This randomized, parallel, placebo-controlled, double-blind clinical trial will evaluate the effects of low-intensity therapeutic ultrasound on muscle recovery after a fatiguing handgrip exercise protocol in healthy adults. Eighty volunteers aged 18 to 45 years will be included and assigned to an intervention group or a placebo group. Participants will perform a handgrip exercise protocol designed to induce muscle fatigue. The intervention group will receive pulsed low-intensity therapeutic ultrasound applied to the wrist flexor and extensor muscles, while the placebo group will undergo the same procedures with the ultrasound intensity set to zero. The main outcome will be pain. Additional outcomes will include muscle strength, perceived exertion, function, range of motion, inflammatory and muscle damage markers, and oxidative stress parameters. Pain will also be assessed 24, 48, and 72 hours after the exercise protocol.