Effect of Low-level Laser Therapy on Exercise-induced Muscle Damage

Federal University of Health Science of Porto Alegre

Status: Completed

Conditions: Muscle Damage

Treatments: Device: Placebo LLLT after muscle damage; Device: Placebo LLLT before muscle damage; Device: LLLT before muscle damage; Device: LLLT after muscle damage

Study type: Interventional

Funder types: Other

Identifiers

NCT02493556

38076514.0.0000.5345

Details and patient eligibility

About

Introduction: The effects of Low Level Laser Therapy (LLLT) on exercise-induced muscular damage have been studied over the last years. Studies have been conducted on animals and humans in order to try to show the benefits of the intervention, but there is still conflicting evidence about its protective and therapeutic effects.

Objectives: To describe the effects of LLLT on pain, strength and muscular inflammation after plyometric exercise.

Methods: A randomized, double-blinded, placebo-controlled trial with participation of 20 male healthy volunteers will be performed. Healthy and physically active individuals, aged between 18 and 35 years, with no history of injury on the lower limbs or contra-indications to maximal exercise performance will be included. A protocol of 10 series with 10 repetitions of the countermovement jump will be used to induce muscle damage at the lower limbs. Immediately before or after the exercise protocol, LLLT will be applied on one lower limb, while the other will receive placebo treatment. Phototherapy will be applied with an equipment of 810nm and a cluster with 5 diodes on 8 different points of the knee extensor muscle, totalizing a dosage of 240J. The placebo treatment will be held on the same way, but the equipment will be turned off. The volunteers will be evaluated at baseline (before the exercise protocol) and at follow-up of 24, 48 and 72 hours. The following outcomes will be evaluated: knee extensors isometric peak torque by Isokinetic Dynamometer, pain by Visual Analogue Scale and muscular tissue echo intensity by Ultrasonography.

Enrollment: 12 patients

Sex: Male

Ages: 18 to 35 years old

Volunteers: Accepts Healthy Volunteers

Inclusion criteria

• Healthy males aged between 18 and 35 years;
• Sedentary or physically active individuals who exercise up to 3 times per week.

Exclusion criteria

• Individuals who participate in systematic exercise training;
• Individuals who participate in strength training for the lower limbs;
• Individuals with lower or upper limb injuries;
• Individuals with contra-indications to maximal exercise performance (due to neurological, cardiovascular or respiratory conditions);
• Individuals who show difficulties to understand the study protocol.

Trial design

Primary purpose: Treatment

Allocation: Randomized

Interventional model: Parallel Assignment

Masking: Double Blind

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12 participants in 4 patient groups, including a placebo group

LLLT before muscle damage

Experimental group

Description:

Low Level Laser Therapy (LLLT) will be applied before the exercise protocol on one lower limb, while the other will receive placebo treatment. Phototherapy will be applied with an equipment of 810nm and a cluster with five diodes on eight different points of quadriceps muscle, totalizing a dosage of 240J.

Treatment:

Device: LLLT before muscle damage

Placebo LLLT before muscle damage

Placebo Comparator group

Description:

Placebo LLLT will be applied before the exercise protocol on one lower limb, while the other will receive real treatment. Placebo treatment will also be applied on eight different points of quadriceps muscle, but the equipment will be turned off.

Treatment:

Device: Placebo LLLT before muscle damage

LLLT after muscle damage

Active Comparator group

Description:

Low Level Laser Therapy (LLLT) will be applied after the exercise protocol on one lower limb, while the other will receive placebo treatment. Phototherapy will be applied with an equipment of 810nm and a cluster with five diodes on eight different points of quadriceps muscle, totalizing a dosage of 240J.

Treatment:

Device: LLLT after muscle damage

Placebo LLLT after muscle damage

Placebo Comparator group

Description:

Placebo LLLT will be applied after the exercise protocol on one lower limb, while the other will receive real treatment. Placebo treatment will also be applied on eight different points of quadriceps muscle, but the equipment will be turned off.

Treatment:

Device: Placebo LLLT after muscle damage