That heavy, achy feeling two days after a hard workout has a name: delayed onset muscle soreness, or DOMS. Could shining red and near-infrared light on tired muscles make recovery a little easier? A 2025 meta-analysis took a careful look.
Study at a glance
- Paper: Effects of Photomodulation Therapy for Delayed Onset Muscle Soreness: A Systematic Review and Meta-Analysis
- Authors: Yung-An Tsou, Nai-Jen Chang, Wen-Dien Chang
- Journal: Journal of Functional Morphology and Kinesiology, July 2025
- Type: Systematic review and meta-analysis (it pools results from several controlled trials)
- Question: Does photobiomodulation (PBM) change soreness and strength after exercise that induces DOMS?
What the research shows
The authors reported a statistically significant reduction in soreness on the visual analogue scale (VAS) at 72 hours (pooled SMD = −0.55) and at 96 hours (pooled SMD = −0.56). In research terms, that is a moderate effect. They also reported improvements in muscle strength at 24 hours (pooled SMD = 0.97) and 48 hours (pooled SMD = 0.99), which is a large effect size.
Soreness was measured in different ways across the included studies, including VAS, the McGill pain questionnaire and pressure pain threshold.
An honest caveat: the picture across the wider literature is mixed. For example, a randomized, controlled, crossover trial using 808 nm photobiomodulation in young adult women did not find improvements in biceps performance to exhaustion or in DOMS. Other reviews describe results that depend heavily on wavelength, dose, timing and how the light is applied. In other words, this is a promising area, not a guarantee.
Why it may work
Red (around 660 nm) and near-infrared (around 810–850 nm) light are thought to be absorbed by components of the mitochondria, the energy-producing structures inside cells. One proposed explanation is that this may support cellular energy production and modulate local inflammation and oxidative stress after hard exercise. These mechanisms are still being studied, and they may not explain every result seen in trials.
Real-world use
Researchers and athletes typically explore PBM at two moments: before training and shortly after it. Those who like to keep their routine simple often fit a session in the evening, alongside stretching or a wind-down ritual. Consistency, not intensity, is the common thread in most protocols.
Where the Gudslip panel fits
The Gudslip® Red & Infrared Light Therapy Panel is a compact device built around 660 nm red light technology. We want to be clear: the study above is about photobiomodulation in general, and the results of a given trial depend on the exact device, wavelength, dose and protocol used. We are sharing the science to explain the concept, not to claim that this specific product will reduce your soreness. Many people simply use it as part of a regular post-training routine and see how their body responds.
How to use it
- Choose a comfortable spot where you can relax with the target muscle area exposed to the light.
- Follow the distance and session length given in the product instructions.
- Protect your eyes: do not stare into the lights and use eye protection if recommended.
- Try it after training or in the evening, on a consistent schedule, for several weeks.
- Keep notes on soreness and sleep so you can judge whether it works for you.
FAQ
Is red light the same as infrared light?
No. Red light is visible (roughly 630–670 nm), while near-infrared is invisible to the eye and is thought to reach somewhat deeper tissue. Both are used in photobiomodulation research.
How soon might I notice something?
The trials measured soreness over 24 to 96 hours after exercise, but individual responses vary and many people use light sessions over weeks rather than once.
Can it replace rest, sleep or good nutrition?
No. Recovery is built on sleep, food, hydration and sensible training load. Light is at most a complement.
Is it safe for everyone?
Not necessarily. If you are pregnant, photosensitive, taking photosensitising medication or have a medical condition, check with a healthcare professional first.
The bottom line
A 2025 meta-analysis found moderate reductions in reported soreness at 72 and 96 hours and notable strength improvements at 24 and 48 hours after photobiomodulation, but other trials found no benefit, so results are not uniform. Light therapy looks like an interesting recovery tool to try alongside the basics, not a miracle.
Disclaimer: This article is for general wellness information only and is not medical advice. Gudslip® products are wellness products and are not intended to diagnose, treat, cure or prevent any disease. Please consult a healthcare professional before starting any new routine, especially if you have a health condition.
References
- Tsou Y-A, Chang N-J, Chang W-D. Effects of Photomodulation Therapy for Delayed Onset Muscle Soreness: A Systematic Review and Meta-Analysis. J Funct Morphol Kinesiol. 2025;10(3):277. doi:10.3390/jfmk10030277
- Photobiomodulation Therapy at 808 nm Does Not Improve Biceps Brachii Performance to Exhaustion and Delayed-Onset Muscle Soreness in Young Adult Women: A Randomized, Controlled, Crossover Trial. PMC8222918