Laser Therapy on Neuromuscular Performance

Immediate Effects of Low-level Laser Therapy (808nm) on Neuromuscular Performance After Muscle Fatigue: Randomized-blinded Clinical Trial

Objective: Investigating the immediate effects of Low Level Laser Therapy (LLLT) on neuromuscular performance in healthy subjects after an induced muscle fatigue protocol. Methods: Eighty volunteers of both genders aged between 18 and 28 years underwent a preliminary evaluation using surface electromyography and isokinetic dynamometer of the flexor muscles of the elbow. The subjects were randomly allocated into 4 groups: G1 was control group; G2 placebo; G3 laser applied before fatigue protocol; and G4 immediately after. Muscular fatigue protocol consisted of 30 maximal concentric isokinetic contractions at 120°/s of the elbow flexor muscles. An 808 nm equipment was used for applying laser therapy, with a power of 100 mW and total energy of 20 J. Volunteers were reassessed after interventions.

Inclusion Criteria:

• Being between 18-28 years of age, having no pain in the shoulder area, elbow or hand, and not having suffered any to injury to the assessed upper limb in the last six months.

Exclusion Criteria:

• Presenting pain that prevented the completion of the evaluation, subjects whose data were improperly recorded or if the volunteer withdrew from the study.