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Published on: March 21, 2015
Low level laser therapy before eccentric exercise reduces muscle damage markers in humans
Bruno Manfredini Baroni1, Ernesto Cesar Pinto Leal Junior, Thiago De Marchi
1Exercise Research Laboratory (LAPEX), Federal University of Rio Grande do Sul (UFRGS), Rua Felizardo, 750-Bairro Jardim Botânico, Porto Alegre, RS, 90690-200, Brazil. bmbaroni@yahoo.com.br
Low level laser therapy (LLLT) before eccentric exercise reduced muscle damage markers and improved muscle function recovery. This therapy attenuated increases in blood serum muscle proteins and decreased muscle force loss post-exercise.
Area of Science:
- Sports Medicine
- Rehabilitation Science
- Biomedical Engineering
Background:
- Eccentric exercise can induce muscle damage, leading to soreness and reduced muscle function.
- Low Level Laser Therapy (LLLT) is explored for its potential therapeutic effects on muscle recovery.
- Understanding LLLT's impact on indirect muscle damage markers is crucial for optimizing training and recovery protocols.
Purpose of the Study:
- To investigate the effect of pre-exercise Low Level Laser Therapy (LLLT) on indirect markers of muscle damage.
- To assess LLLT's influence on muscle soreness, serum enzyme levels (LDH, CK), and muscle function (MVC) following eccentric exercise.
Main Methods:
- Thirty-six healthy men were randomized into LLLT and placebo groups.
- Subjects underwent 75 maximal knee extensor eccentric contractions after LLLT or placebo application.
- Muscle soreness (VAS), lactate dehydrogenase (LDH), creatine kinase (CK), and maximal voluntary contraction (MVC) were measured at multiple time points pre- and post-exercise.
Main Results:
- The LLLT group showed a significantly smaller increase in LDH and CK levels at 48 hours post-exercise compared to the placebo group.
- LLLT significantly attenuated the decrease in maximal voluntary contraction (MVC) immediately after, and 24 and 48 hours post-exercise.
- No significant difference was observed in muscle soreness (VAS) between groups.
Conclusions:
- Pre-exercise LLLT effectively attenuates the increase in serum muscle proteins (LDH, CK) following eccentric exercise.
- LLLT enhances the recovery of muscle force (MVC) after strenuous eccentric contractions.
- LLLT demonstrates potential as an effective intervention to mitigate muscle damage and accelerate recovery from eccentric exercise.
