Red light therapy, which is also known as low-level light therapy (LLLT), is popular among professional athletes and fitness enthusiasts as a way to achieve peak performance by building muscle, delaying the onset of fatigue, and accelerating muscle recovery. The question is, should you use red light therapy before or after a workout?
Here, we’ll break down the benefits of pre- and post-workout red light treatments so you can make an informed decision based on your goals, and to prevent and treat injury.
The Science Behind Red Light Therapy Before, During, and After a Workout
Hundreds of peer-reviewed clinical trials have shown that red light therapy promotes enhanced physical performance. This includes improvements in strength, speed, and endurance; faster muscle recovery after strenuous workouts; and faster return-to-play after injury.
The biggest question is, will you see more benefits from using red light therapy before or after a workout? Here’s the science that supports both approaches, as well as other options.
Red Light Therapy Before a Workout
The most compelling arguments appear to favor using pre-exercise light therapy with red and/or near-infrared (NIR) light. The term “red light therapy” is often used as an umbrella term that applies to both red and NIR light.
A 2015 meta-analysis by researchers from São Paulo, Brazil, concluded that red light applied before exercise resulted in significant improvement in time-to-exhaustion, number of repetitions, and accelerated post-exercise recovery.
In a 2012 study, 22 untrained male athletes received either NIR light therapy or a placebo five minutes before a progressive-intensity running test performed to exhaustion. The treatment group exhibited increased exercise performance and decreased exercise-induced oxidative stress and muscle damage.
In a 2018 study, 16 male athletes were assigned to four groups. Three of the groups received red light therapy at different intervals before exercise, and the control group received no treatment. All treatment groups showed significantly reduced fatigue compared with the control group.
Also in 2018, researchers from Brazil conducted a study involving 48 male volunteers. Over a period of 12 weeks, some of the volunteers received red light before exercise, some after, and the control group received a placebo. Pre-workout light therapy treatments led to significant changes in strength and muscle growth compared with the post-workout and placebo groups. The researchers suggested that the treatment may also assist with post-injury strength-building rehabilitation.
An earlier study on ten professional volleyball players on the effect of red light on muscle fatigue. Low-level light therapy applied immediately before exhaustive biceps exercises caused a slight delay in the development of skeletal muscle fatigue and a decrease in post-exercise blood lactate levels.
A 2015 study of 30 men in Brazil found that red light therapy prior to knee exercises led to statistically significant gains in knee extensor muscle thickness and peak power produced.
Twenty male competitive cyclists participated in a 2018 study on neuromuscular fatigue. The treatment group received red light therapy prior to time-to-exhaustion cycling tests. Those who were treated showed increased exercise tolerance: maximum oxygen uptake, maximum power output, and time-to-exhaustion tests.
In 2017, researchers from Brazil conducted a study to investigate the effect of red light therapy before grip strength protocol in healthy subjects. Those who were treated showed statistically significant gains in handgrip strength.
A measurable difference in the onset of muscle fatigue and exhaustion was shown in a 2008 study of 12 male professional volleyball players performing bicep curls. The red light treatment group was able to perform an average of 8.5 more repetitions than the placebo group.
Red Light Therapy During a Workout
Since it’s not practical to administer light therapy during most workouts, there are only a few studies on the effects of red light during exercise. However, you could comfortably use LED light treatments during workouts on a treadmill, stair stepper, or stationary bike.
One 2018 study involved 15 male recreational runners. Physiological and performance variables were measured during running tests, including rate of perceived exertion, running economy (efficiency), speed, total time-to-exhaustion, and total distance covered. The treatment group experienced significantly higher performance in these measurements.
A group of 30 post-menopausal women participated in a 2014 study by researchers from Brazil. Ten of the women received red light treatments during treadmill training, 10 did the treadmill without red light, and 10 neither exercised nor received red light treatment. Compared to the others, the treadmill/red light group showed increased quadriceps power and decreased fatigue.
Red Light Therapy During and After a Workout
Due to the impracticality of applying red light during most types of exercise, only one study focused on its effects when used during exercise as well as afterward. It was a small study, conducted in 2014, that assessed knee flexion strength. The treatment group received NIR light therapy between sets, as well as after the last set of exercises. Compared with the placebo group, those receiving NIR therapy showed increased gains in strength and increased muscle fatigue resistance.
Red Light Therapy After a Workout
Post-workout light therapy is a convenient way to accelerate recovery; but as one study shows, it can also improve performance.
In a 2016 study of a pair of identical twins, stimulating the quadriceps muscles with red light immediately after a workout resulted in reduced muscle damage and pain, and increased muscle mass, recovery, and athletic performance.
Thirty-six males with beginner or moderate physical activity habits participated in a 2011 study by researchers from Brazil and the United States. The study revealed that red light performed immediately after a leg-press exercise increased muscle performance compared with strength training only.
Red Light Therapy Before and After a Workout
Applying red light both before and after a workout shows great results over choosing treatment only before or only after workouts.
In 2018, 77 volunteers participated in a 12-week study involving treadmill training. One group received red light before and after exercise; one group received red light before and placebo after; one group received placebo before and red light after; and one group received a placebo before and placebo after. Participants who received red light before and after treadmill training saw a significant increase in time-to-exhaustion and oxygen uptake, and a reduction in body fat.
How Red Light Therapy Benefits Athletic Performance
Red light therapy has the potential to improve muscle healing from intense training. It has been shown in multiple clinical trials to offer pain relief and support muscle recovery, bone and connective tissue healing from sports-related injuries, and to increase strength, speed, and endurance.
Whether you’re an elite athlete training for competition, a fitness enthusiast looking to sculpt and tone your body, or a weekend warrior who’s just out there for fun and looking to improve muscle performance, red light can help you enjoy your sport at your peak.
Red Light Therapy Promotes Faster Muscle Recovery After a Workout
Exercise-induced muscle damage is a normal part of any workout; exercise causes microscopic tears in the muscle fibers and the repair process leads to muscle growth. The faster your muscles recover after a workout, the sooner you can resume the desired exercise intensity with less risk of injury.
A 2014 study revealed that red light treatments produced a positive effect on muscle recovery after “damaging eccentric exercise” (bicep curls using the non-dominant arm). Muscle soreness, muscle weakness, and range of motion impairment were significantly improved up to 96 hours after exercise.
In a 2016 clinical trial, high-level rugby players were observed during an anaerobic fitness test. The athletes treated with red light showed significant improvements in sprint times and delayed the onset of actual and perceived muscle fatigue.
Red Light Therapy Can Prevent Delayed Onset Muscle Soreness
Every type of exercise comes with the potential for post-workout soreness, which can lead to a break in exercise habits and loss of motivation. Delayed-onset muscle soreness (DOMS) is the pain and stiffness that affects muscle tissue 24 to 72 hours after a novel workout – the kind of pain that has you saying, “I’m hurting in muscles I didn’t even know I had.”
Preventing post-workout soreness in muscle tissue is a big priority for faster return to your sport without pain, and without having to wait days or even weeks for muscles to recover.
Red and NIR light therapy has been shown to minimize DOMS, such as in this 2006 study of 27 subjects. The study lasted five consecutive days, after which the NIR treatment group experienced a significant decrease in DOMS pain over the sham treatment and control groups.
Red Light Therapy Can Accelerate Healing from Sports Injuries
Many people associate contact sports with injury. But even non-contact and non-impact sports like cycling or yoga come with the potential for overuse injury, joint pain, nerve pain, muscle injury, and connective tissue damage.
The main intent of most treatments is to get you back to your sport quickly, whether you’re sidelined from overtraining or muscle injuries.
Combining red light therapy with conventional therapies like RICE (rest, ice, compression, and elevation) and other doctor-prescribed treatments could potentially support healing of common sports injuries, including:
- Running: Runner’s knee, shin splints, Achilles tendinitis, iliotibial band pain, hamstring pulls, plantar fasciitis, hip pain, and stress fractures in the feet;
- Weight training: Shoulder impingement (swimmer’s shoulder), injury to the patellar tendon in the knee, and back sprains and strains;
- Cycling: Knee pain, Achilles tendinitis, lower back strains, and neck strains;
- Swimming: Shoulder impingement, shoulder inflammation, rotator cuff tendonitis or tears, cartilage tears around the shoulder, neck pain, low back pain, and bicep tendonitis;
- Baseball/Softball: Rotator cuff tears, knee injuries, low back sprains, and muscle sprains and strains;
- Tennis: Tennis elbow, knee injuries, rotator cuff tendonitis, wrist strains, back pain, and Achilles tendon strains.
Many competitive athletes are trained to push through the pain no matter what, which can lead to chronic inflammation and a delayed healing response. NIR light is especially beneficial in reducing chronic inflammation because of how its longer wavelengths absorb deep into muscle, connective tissue, and even bone.
A 2016 study involving injured university athletes revealed that NIR light promoted significantly faster muscle recovery and return-to-play after just a few sessions. The researchers found that NIR light enhanced blood flow, reduced inflammation, relaxed muscle spasms, and minimized the time participants reported feeling pain.
Achilles tendinitis is a persistent problem among runners, cyclists, and other types of athletes. A 2006 study examined the effects of NIR light therapy on seven patients with bilateral Achilles tendinitis and found significantly less inflammation and a higher pressure pain threshold after treatment.
How Red Light Therapy Works
Red light therapy involves using devices fitted with LED bulbs that shine red and NIR wavelengths of light at the skin. Red/ NIR therapy ranges from 630 nanometers (nm) to 850 nm, which is known as the “therapeutic window” of light.
This treatment modality has innumerable beneficial effects on the human body. The benefits occur at the cellular level, stimulating natural biological processes in the treatment areas.
Improved Cellular Energy
Mitochondrial dysfunction is a term that applies to the inability of the cells’ mitochondria (energy-producing organelles within cells) to produce enough cellular fuel. These cells are more vulnerable to oxidative stress, heal more slowly from damage, and don’t replicate successfully.
When red and NIR light interact with photoreceptor molecules in mitochondria, this interaction stimulates energy production in the cells.
Cells that perform their specialized functions at optimal levels (and successfully replicate and perform cellular repair), lead to accelerated healing in injured or inflamed muscles and improved muscle performance.
Reduced Chronic Inflammation
Acute inflammation is a short-term healing response – a function of a healthy immune system. But chronic inflammation is not healthy; it causes a number of physical problems including oxidative stress, which is an imbalance between free radicals and antioxidants in the body.
According to a 2018 study, red light therapy reduces oxidative stress in the muscles through changes in mitochondrial metabolic energy processes. When the light photons stimulate the mitochondria to produce more adenosine triphosphate (ATP), this gives them the resources to combat oxidative stress, which in turn supports muscle recovery.
Increased Blood Flow
Red light has been shown to stimulate increased blood flow. Increased circulation of both the cardiovascular and lymphatic systems means more nutrients and oxygen are delivered to cells, as well as more efficient removal of waste materials that could interfere with optimal muscle functioning and recovery.
During a 2017 study, researchers from Slovenia observed the effects of red wavelengths on wound healing among diabetic and non-diabetic patients. The study revealed that treatment with red and NIR light three times a week for eight weeks increased blood flow in both diabetic and non-diabetic study participants.
Increased Collagen Production
Collagen is a protein most commonly associated with healthy skin tone, but it is also a key component of muscle and connective tissue, including cartilage. Type I collagen is found in the bones, tendons, ligaments, and skin; type III collagen is found in cartilage; and type III collagen is found in muscles and organs.
Stimulating collagen production can aid in repairing micro-tears in muscles or larger traumatic injuries to muscle tissue, including tears and blunt trauma.
If you suffer from knee or hip pain, red light therapy may ease pain and restore normal biomechanics by restoring the cartilage in the joints.
Numerous studies on osteoarthritis have shown that the treatment can stimulate production of collagen deeper in the body.
During a 2021 review of numerous studies, researchers concluded that red light therapy has positive effects on cartilage repair and prevention of further cartilage degradation, and could be considered a treatment for osteoarthritis.
A 2017 study by researchers from Saudi Arabia found that red light therapy has an analgesic (pain relieving) effect as well as a cartilage regeneration effect. The treatment group received three treatments per week for four weeks and showed significant differences in cartilage thickness and reduced pain.
A 2011 study showed that treatment with red wavelengths (660 nm) resulted in increased Type I and III collagen synthesis and faster regeneration of skeletal muscle tears.
A similar 2016 study analyzed the effects of 850 nm NIR light on muscle injury. The researchers found an increase in collagen during the muscle repair process following injury.
At-Home Red Light Therapy
Whether you apply red light before or after workouts, you don’t have to visit a physical therapist or work with a coach, and you don’t have to be an elite athlete in order to experience the benefits. Here's how at-home treatments can boost your physical performance.
The Right LED Light Therapy Device
Some studies used low-level laser therapy to apply red light therapy; the outcomes are expected to be similar when using LED devices. Low-level laser therapy is usually administered by a professional, whereas LEDs can be used for at-home treatments.
A high-quality, high light energy output LED device such as the BIOMAX 900 will deliver a combination of the most beneficial red and near-infrared light wavelengths for improving physical performance: red light (630 and 660 nm) and NIR light (810, 830, and 850 nm).
This combination of red and NIR light ensures that every layer of tissue receives the treatment; you never have to choose between red or near-infrared light.
Red light treats the skin as well as tissue that is just beneath the skin, including muscle, bone, and connective tissue (such as in the hands, feet, knees, neck, and ankles).
Near-infrared light absorbs into deeper tissues and can benefit large muscle groups that are out of reach of shorter-wavelength red light.
For deep-tissue treatment, you'll want a powerful device that delivers maximum light energy to obtain the desired results, especially when treating a larger area of the body.
A larger panel will treat a larger area of the body (such as the muscles in the lower body) and deliver more light energy power than smaller devices. The PlatinumLED BIOMAX series panels are modular, letting you link two to four panels together to increase coverage and boost power.
Check out this comparison video to get an idea of how important it is to use a high-light-energy output device (scroll down the page to see the video).
Consistent Treatment For the Best Results
A five- to 20-minute session of applying red light to bare skin (not through clothing) before and/or after a workout gives you time to stretch, mentally rehearse success, and hydrate.
With consistent use, you may experience immediate improvements in strength, speed, and endurance. Since red light works at the cellular level, the best results will likely come over time.
Long-term healing of sports injuries may require several weeks of therapy.
Since red/NIR light is considered to be safe, you can continue to use it indefinitely to help maintain peak physical performance in any sport.
Red Light Could Be a Revolution in Physical Performance
The answer to whether it's best to receive red light therapy before or after workout appears to be twofold:
- Pre-workout red/NIR treatments support improved performance, prevent exercise-induced muscle tissue damage, and improve post-workout recovery of strength and function.
- Post-workout red light therapy helps promote healing of sports injuries and assists with physical rehabilitation and recovery from chronic joint pain.
Red light therapy improves performance for both professional athletes and amateurs. It can help sacroiliac joint pain, AC joint pain, improving running speed, knee pain after running, speeding up recovery from a run, and more.
Since red light therapy has so many applications for natural health and wellness, you may be pleasantly surprised by its other effects including better skin tone, improved joint mobility, and relief from chronic skin conditions. Visit the PlatinumLED Learn page to read all about how to use this natural therapy to improve athletic performance and overall well-being.
Now that you know the benefits of using red light therapy before or after a workout, you can safely use the most powerful light therapy devices from PlatinumLED to supercharge your fitness and help you achieve – and exceed – your fitness and athletic goals.