Laser Therapy on Neuromuscular Performance

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

Status

Completed

Phases

Study type

Interventional

Source

ClinicalTrials.gov

Registry ID

NCT02813395

Enrollment

Registered

2016-06-27

Start date

2014-04-30

Completion date

2015-08-31

Last updated

2016-06-27

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Fatigue

Brief summary

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.

Interventions

DEVICELow Level Laser Therapy

Low Level Laser Therapy was applied at four points to the dominant upper limb of the volunteers on the muscle belly of the biceps. Delineation was done using a measuring tape from the elbow joint line to the acromion marked at points corresponding to 20%, 30%, 40% and 50% of this distance, focusing the application on the muscle belly region, thereby excluding the tendinous region. An 808 nm equipment was used for applying laser therapy, with a power of 100 mW and total energy of 20 J.

DEVICEPlacebo Laser

Laser application simulation with a second pen of the laser device, which was disconnected and did not effectively irradiate energy.

Study design

Allocation

RANDOMIZED

Intervention model

PARALLEL

Masking

TRIPLE (Subject, Investigator, Outcomes Assessor)

Eligibility

Sex/Gender

ALL

Age

18 Years to 28 Years

Healthy volunteers

Yes

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.

Design outcomes

Primary

Measure	Time frame
Peak torque normalized by body weight	Change from baseline to one hour.

Countries

Brazil

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: Feb 4, 2026