Red light for muscle recovery: what exercise studies found

Ferraresi, Huang and Hamblin (2016) reviewed 46 studies with 1,045 participants. They noted that studies used single laser probes, laser clusters, LED clusters and flexible LED arrays, and that results were sorted into settings that worked and settings that didn't.

One thing worth knowing: Ernesto Leal-Junior is an author on three of the reviews on this page, and his São Paulo laboratory specialises in phototherapy for sport and exercise. That doesn't make the findings wrong. It does mean independent replication matters.

The reviews on soreness are more mixed

Nampo and colleagues (2016) looked specifically at muscle damage and soreness. They found 15 studies with 317 participants. Light applied before exercise was linked with lower creatine kinase only when lasers were used, and there was no difference in swelling, range of movement or strength. Their conclusion was that low-level light may not have a substantial effect on exercise-induced muscle damage and pain.

Chen and colleagues (2025) compared several recovery methods for DOMS in a network meta-analysis. Light treatment showed less soreness than placebo at 24 and 48 hours, but beyond 48 hours there was no notable benefit from any of the methods compared with placebo.

Ferlito and colleagues (2022) compared light with cold therapy in four trials with 66 people. Light came out ahead on strength, soreness and damage markers, but the certainty of evidence was rated moderate to very low. Four small trials isn't much to build on.

Whole-body studies: closer to a panel, and less positive

Most of the trials above held a probe or LED cluster directly against a muscle. That's quite different from standing in front of a panel. The studies that used whole-body light beds are closer to home use, and their results are notably weaker.

Ghigiarelli and colleagues (2020) gave 12 trained men a whole-body light session around a hard resistance workout, in a crossover design. There was no significant difference in creatine kinase or in a saliva marker of inflammation compared with the control condition.

Zagatto and colleagues (2020) tested full-body light on 13 young water polo players after official matches, against a placebo. They found no meaningful differences in hormones, inflammation, muscle damage, strength, jump height or heart rate variability, apart from one isolated marker after the first match.

Forsey and colleagues (2023) ran the largest of the three: 48 active men and women, single-blind, crossover, with 20 minutes of whole-body light before repeated sprint cycling tests. Light didn't improve power output or lactate. Heart rate variability the next morning was higher after the light session, which the authors read as a sign of better recovery. But there was no difference in how recovered or stressed people said they felt.

What the trials had in common

When light did show an effect, the settings were specific. Vanin and colleagues reported most positive results with wavelengths from 655 to 950 nm and doses measured in total joules per muscle group. Leal-Junior and colleagues found the most consistent results with light used before exercise.

Neither tells you what a home panel delivers. That depends on its output at your distance and the time you spend in front of it, which is why we wrote a guide to reading device specifications.

How to read this

If someone tells you red light is proven to speed recovery, they're overselling. If someone tells you there's nothing to it, that's also not quite right. A fair summary is: some small effects on performance measures in lab trials, mostly with probes on the muscle; inconsistent effects on soreness; and little to show from the whole-body studies so far.

If you try light at all, treat it as an extra, not a replacement for sleep, food and rest days.

Who should check with a doctor first

If you have an injury, ongoing pain, or soreness that doesn't settle within a few days, see a GP or physiotherapist rather than reaching for a device. Talk to your GP or pharmacist first if you're pregnant, take medicine that makes your skin sensitive to light, have an eye condition, or have epilepsy triggered by flashing lights. Read our pages on eye safety and side effects as well.

What we won't say

We won't tell you our panels speed up recovery, reduce soreness or improve performance. No trial has tested them, and their specifications aren't final. For where the research is heading next, see the future of recovery and red light.