How Red and Near-Infrared Light May Support Muscle Recovery and Joint Comfort

Recovery is an important part of an active lifestyle.

Whether you exercise regularly, spend long hours at a desk, or want to learn more about recovery technologies, you may have come across red light therapy and near-infrared light therapy.

These approaches are often discussed under the term photobiomodulation (PBM), which describes the use of specific wavelengths of light to produce biological effects.

Researchers have investigated PBM in areas such as exercise recovery, muscle soreness, tendon conditions, and musculoskeletal pain. But what does the evidence actually show, and what should you consider before using a light therapy device?

What Is Photobiomodulation?

Photobiomodulation uses red or near-infrared light to interact with biological tissues. Researchers are studying how light exposure may influence cellular processes associated with inflammation, pain, and tissue function.

However, PBM is not a single standardized treatment. Studies use different light sources, wavelengths, power levels, treatment durations, and application methods. These differences can influence the results.

For this reason, findings from one clinical study cannot automatically be applied to every light therapy device.

Red Light vs. Near-Infrared Light

Red and near-infrared light occupy different parts of the light spectrum.

Red Light

Red light is visible to the human eye and has been studied in skincare and other photobiomodulation applications.

Its effects depend on the wavelength and the amount of light energy delivered to the treatment area.

Near-Infrared Light

Near-infrared light lies just beyond the visible red spectrum and cannot normally be seen by the human eye.

Some near-infrared wavelengths can penetrate tissue differently from visible red light. However, penetration depth varies with wavelength, tissue characteristics, and device parameters. Near-infrared light should not be assumed to reach a particular muscle or joint effectively simply because a device emits it.

Some devices combine red and near-infrared wavelengths, but combining wavelengths does not guarantee better results.

Can Photobiomodulation Support Muscle Recovery?

Researchers have explored whether PBM can influence muscle performance, post-exercise soreness, and recovery.

A 2025 systematic review examining whole-body PBM identified only five relevant studies involving 105 physically active participants. Although some studies reported improvements in sleep-related measures, none found a benefit in exercise performance or fatigue biomarkers. The authors concluded that evidence for whole-body PBM as a recovery or performance aid remains insufficient.

Other research has investigated more localized treatment.

A 2025 systematic review and meta-analysis examined near-infrared light applied before lower-limb exercise. The review included 21 studies and reported improvements in some measures of muscle performance and exercise-related outcomes. However, the studies varied in their protocols, and the findings should be interpreted cautiously.

Taken together, the evidence suggests that some specific PBM protocols may influence certain recovery outcomes, but benefits are not consistent across applications.

The type of device, treatment timing, dose, and area treated all matter.

Near-Infrared Light and Post-Exercise Soreness

Delayed-onset muscle soreness, commonly known as DOMS, can develop after unfamiliar or intense exercise. It often becomes noticeable during the hours following activity.

Researchers have investigated whether near-infrared light applied before exercise can affect subsequent soreness and muscle function.

The findings are promising in some studies, but important questions remain about the most effective treatment parameters and how consistently the results can be reproduced.

It is also important to distinguish research involving targeted laser treatment from research involving LED panels, wearable devices, or whole-body systems. These approaches may deliver different amounts of energy to the tissue.

A result obtained with one protocol does not establish that another device will produce the same outcome.

What About Joint Comfort?

PBM has also been studied in people with musculoskeletal conditions, including knee osteoarthritis.

A systematic review and meta-analysis involving 10 studies and 542 participants reported a reduction in pain at rest compared with placebo. However, the researchers rated the certainty of this evidence as very low, and some functional outcomes did not show a significant benefit compared with placebo.

This distinction matters. A statistically significant finding does not necessarily establish a reliable, meaningful benefit for every person.

The evidence does not show that red or near-infrared light can resolve every type of joint discomfort, repair joint damage, or replace appropriate medical treatment.

Anyone experiencing persistent, severe, or worsening joint pain should seek advice from a qualified healthcare professional rather than relying on light therapy alone.

Red Light Therapy and Tendon Health

Researchers have also investigated PBM for tendinopathy, a group of conditions involving tendon pain and impaired function.

A systematic review and meta-analysis published in 2021 included 17 randomized trials involving 835 participants. It found that PBM combined with exercise was associated with greater improvements in pain and function than sham treatment combined with exercise in some comparisons.

However, results differed depending on the comparison group and outcome measured. The evidence quality also varied, and the findings do not establish PBM as a standalone treatment for tendon conditions.

The practical takeaway is that light therapy may be worth investigating as a potential complement to an appropriate rehabilitation plan, but it should not replace prescribed exercises, physical therapy, or professional medical care.

When Do Researchers Use Light Therapy for Recovery?

Studies have examined PBM at different points in relation to exercise, including before activity and after exercise.

The appropriate timing depends on the specific protocol being studied. There is no single schedule that has been established as best for every person, activity, or device.

If you are considering a light therapy device, follow its instructions and use it only for applications supported by the manufacturer's guidance. Do not increase exposure time or frequency in an attempt to accelerate recovery.

Building a Balanced Recovery Routine

Light therapy, where appropriate, should be considered alongside the fundamentals of recovery.

A balanced routine may include:

• Sleep: Allow adequate time for rest and recovery.
• Nutrition: Eat enough to support your activity level and overall needs.
• Hydration: Replace fluids appropriately, particularly after sweating.
• Movement: Include suitable mobility work and gradual activity progression.
• Rest: Allow time between demanding training sessions.
• Exercise planning: Adjust intensity and volume to your fitness level and recovery needs.

These habits support general health and physical recovery, regardless of whether you choose to explore light therapy.

Why Treatment Parameters Matter

Not all red and near-infrared light therapy devices deliver the same treatment.

When comparing devices intended for a specific application, consider the following specifications:

• Wavelength: The wavelength or wavelengths emitted by the device.
• Irradiance: The amount of optical power delivered per unit area at the treatment position.
• Energy density: The amount of energy delivered per unit area over a specified period.
• Treatment time: The duration recommended for each session.
• Treatment area: Whether the device is designed for a small, targeted area or broader coverage.
• Treatment distance: How far the device should be from the body, where applicable.
• Safety guidance: Recommended frequency, precautions, and intended use.

These details help explain why two devices marketed as red and near-infrared light therapy products may deliver different exposures.

A higher power rating or a longer session does not automatically mean a better outcome. Follow the recommended protocol for the specific device and intended application.

What Can You Realistically Expect?

It is best to approach photobiomodulation with realistic expectations.

Current research suggests potential benefits in certain applications, including some measures of exercise recovery and pain. However, findings vary across studies, and the quality of evidence is not equally strong for every outcome.

Avoid assuming that light therapy will provide instant recovery, eliminate joint pain, prevent injuries, or guarantee better athletic performance.

Instead, consider three questions:

1. Is the device designed for the application you have in mind?
2. Are its treatment parameters and instructions clearly specified?
3. Does the evidence support the intended use, and are you following appropriate safety guidance?

These questions can help you evaluate claims more carefully.

Final Thoughts

Red and near-infrared photobiomodulation are active areas of research in exercise recovery and musculoskeletal health.

Some studies report encouraging results for specific treatment protocols, while others find limited or no measurable benefits. Differences in devices, wavelengths, treatment doses, and study design make broad conclusions difficult.

The most sensible approach is to stay informed, choose devices intended for your specific needs, and follow their instructions carefully.

Light therapy should complement—not replace—appropriate exercise, recovery habits, rehabilitation, or professional medical care.

Research References

For readers who want to explore the evidence further:

1. Álvarez-Martínez M, Borden G. A systematic review on whole-body photobiomodulation for exercise performance and recovery. Lasers in Medical Science, 2025. https://doi.org/10.1007/s10103-025-04318-w
2. Peng P, et al. The Effects of Near-Infrared Phototherapy Preirradiation on Lower-Limb Muscle Strength and Injury After Exercise: A Systematic Review and Meta-analysis. Archives of Physical Medicine and Rehabilitation, 2025. https://doi.org/10.1016/j.apmr.2024.04.013
3. Effectiveness of Photobiomodulation in Reducing Pain and Disability in Patients With Knee Osteoarthritis: A Systematic Review With Meta-Analysis. Physical Therapy, 2024. https://doi.org/10.1093/ptj/pzae073
4. The effect of low-level red and near-infrared photobiomodulation on pain and function in tendinopathy: a systematic review and meta-analysis of randomized control trials. BMC Sports Science, Medicine and Rehabilitation, 2021. https://doi.org/10.1186/s13102-021-00306-z