Photobiomodulation and Muscle Recovery: A Comparative Meta-Analysis with Other Physical Modalities

In this meta-analysis, photobiomodulation administered before exercise was associated with a significant reduction in muscle soreness, amounting to a 12.27-point decrease on the pain scale. Neuromuscular electrical stimulation and intermittent pneumatic compression administered after exercise did not reduce muscle soreness in this same review.

What this study measured

Exercise-induced muscle damage limits performance and the frequency of training sessions. The authors compared three recovery methods: photobiomodulation, neuromuscular electrical stimulation, and intermittent pneumatic compression.

Four databases were searched in July 2023. Only randomized clinical trials conducted in healthy, asymptomatic participants aged 18 years or older were included. Two independent authors selected the studies, assessed the risk of bias, and evaluated the certainty of the evidence using the GRADE method. Nineteen studies involving 672 participants were included. The abstract does not mention a PROSPERO registration.

Key Findings

Only one of the three methods achieved statistical significance in terms of muscle soreness—photobiomodulation—provided it was applied before exercise.

• Pre-exercise photobiomodulation, muscle soreness: mean difference of -12.27 points (95% CI -18.14 to -6.40), I² = 48%, evidence of low certainty according to GRADE.
• Neuromuscular electrical stimulation, muscle soreness immediately after the procedure: -4.60 points (95% CI -20.03 to 10.83), not significant, low certainty.
• Intermittent pneumatic compression, muscle soreness at 24 hours: -2.20 points (95% CI -10.08 to 5.68), not significant, moderate certainty.
• Scope: 19 randomized trials, 672 healthy participants aged 18 or older; research conducted in July 2023.

The authors also conclude that photobiomodulation before exercise increases muscle performance as measured 24 hours after an exercise session that causes muscle damage, without specifying the magnitude of this effect.

How photobiomodulation works for this indication

The mechanism remains hypothetical and is not measured in this review. Red and near-infrared light is thought to be absorbed by cytochrome c oxidase, the terminal complex of the mitochondrial respiratory chain, which could increase ATP production and energy availability in the muscle prior to exercise. A modulation of oxidative stress and post-exercise inflammation is also suggested. The fact that the benefit occurs when exposure precedes exercise suggests preconditioning rather than repair.

Limits You Should Know

The authors consider the certainty of the evidence to be low regarding the beneficial effects of photobiomodulation; future research could change this assessment. Heterogeneity reaches 48%, indicating significant variability among studies.

The result has been demonstrated only under a specific set of conditions: exposure before exercise, in healthy, asymptomatic adults. It cannot be generalized to muscle disorders, the elderly, or post-exercise application. The results for the other two modalities are negative, with confidence intervals that extend well beyond zero. The total sample size—672 participants across 19 trials and three modalities—remains modest. Finally, the abstract provides no information on wavelength, dose, or optimal timing.

What This Means in Practice

For an athlete, the key takeaway is a matter of timing. In this meta-analysis, the benefit in reducing muscle soreness is observed when photobiomodulation precedes the workout, not when it follows it. The reported reduction of 12.27 points was measured using pain scales whose format was not specified. This result is not a substitute for either progressive training or sleep.

Frequently Asked Questions

Does photobiomodulation reduce muscle soreness?

In this meta-analysis of 19 trials involving 672 healthy participants, yes, provided it is applied before exercise. The reported reduction is 12.27 points (95% CI -18.14 to -6.40), with 48% heterogeneity and low certainty of evidence according to GRADE. The authors also report improved muscle performance 24 hours after exercise.

Should you use it before or after your workout?

The significant finding of this review pertains to application before exercise. The authors do not establish an equivalent benefit for application after exercise. The abstract does not specify either the optimal timing or the irradiation parameters, which makes it impossible to derive a protocol from it.

Which is more effective: electrical muscle stimulation or compression boots?

No, not in this analysis. Neuromuscular electrical stimulation showed an average difference of -4.60 points (95% CI -20.03 to 10.83) in muscle soreness immediately after the intervention, and intermittent pneumatic compression showed a difference of -2.20 points (95% CI -10.08 to 5.68) at 24 hours. Neither of these results is statistically significant.

Reference

Canez MS, da Silva LI, Ferreira GD, de Araújo FX, Luza LP. Effects of photobiomodulation, intermittent pneumatic compression, and neuromuscular electrical stimulation on muscle recovery: A systematic review with meta-analysis. Journal of Bodywork and Movement Therapies, 2025. PMID 40954632. View the study on PubMed

This summary is provided for informational purposes only and does not constitute medical advice. Photobiomodulation is not a substitute for prescribed treatment. Consult a healthcare professional.