Red Light Therapy for Muscle Injury

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Red light therapy is becoming an unfair advantage that can’t be banned from amateur or professional sports. Here are 7 more studies showing how this therapy keeps athletes on the field.

Takeaways:

Studies show that red light therapy helps athletes with injuries:

Reduces ankle sprain pain after one session
Reduces ankle sprain pain after two sessions
Reduces ankle sprain edema
Returns athletes from injury to play up to 71% faster
Reduces shoulder tendinitis pain faster than naproxen sodium
Improves Achilles tendinitis healing time faster when prefaced with ice therapy
Speeds eccentric exercise tendinitis physical therapy

Don’t remember the difference between a sprain and a strain? See my article: Soft Tissue Injury & Muscle Pain that Prevent Athletic Play

Red Light Therapy for Sprains

Several studies show that red light therapy can help heal sprained muscles. Using the light reduces bruising, edema, and pain.

Study #1 Red Light Therapy Reduces Ankle Sprain Pain by 30.81%

Red light therapy helps with the pain and bruising of ankle sprains, according to a 2018 study published in Lasers in Medicine and Science.

This study showed that red light therapy can reduce ankle sprain pain by as much as 30.81%. Red light therapy reduced ankle sprain pain by 30.06% and 30.81%, based on improvements in the McGill and Visualized Analog Scale (VAS) pain assessment tests[1]. This study used 10 joules/cm^2 of 627 nm red light on 40 volunteers with acute ankle sprains.

Person's hands holding red, inflamed ankle — Red light therapy helps with Achilles heel tendonitis

All volunteers received protection, rest, ice, compression, and elevation. Then, 20 received red light therapy, and 20 received a sham treatment for the next 6 days. In addition to reducing the perception of pain by about 31%, the treatment group experienced significantly less bruising after 6 days of red light therapy.

Study #2 Multiple Red Light Therapy Sessions Reduce Ankle Sprain Pain

Red light therapy reduces pain in moderately severe ankle sprains, according to a 2019 study published in the American Journal of Physical Medicine and Rehabilitation[2].

The authors tested an unusual protocol that worked despite prior indications that it would not. Red light therapy’s “biphasic dose-response” says that too much light is counterproductive.

Soccer player with blue socks kicking soccer ball — Red light therapy helps with muscle sprain healing and pain relief

Here, the subjects received two doses of red light in one session, and the results were still positive. Both groups had moderately severe ankle sprains.

Group 1 received a red light therapy session, then a second session after a 30-minute break. Their ankles received two sessions of 635 nm red light for three days, for a total of 6 treatment sessions.

Group 2 received rest, ice, compression, and elevation therapy. Researchers then tested the subjects’ recovery 10 days and 6 weeks after treatment. The treatment group’s patients with sprained ankles experienced significantly less pain at 10 days but not at 6 weeks. One would not expect a pain reduction from 3 days of treatment a month and a half earlier.

Study # 3 Red Light Therapy Reduces Ankle Sprain Edema

Red light therapy reduces the edema associated with ankle sprains, according to a study in the Journal of Clinical Laser Medicine & Surgery[3].

Ankle sprains often cause edema and swelling from the trapped fluid. The swelling adds to the pain sensation of a sprained ankle. Researchers tested reducing edema with these treatment combinations:

16 subjects: rest, ice, compression, elevation
16 subjects: rest, ice, compression, elevation, placebo red light therapy
15 subjects: red light therapy

Soccer player chasing ball with opponent running behind him — Red light therapy helps with chronic inflammation reduction

They studied these protocols on soccer players. The red light therapy was 820 nm infrared pulsed at 16 Hz. They found that red light therapy reduced edema significantly more than traditional and placebo light therapy treatments. Studies on intercostal, abdominal, and shoulder muscle strains have shown that red light therapy helps with these strains.

Study #4 Post-Injury Return-to-Play 71% Faster with Red Light Therapy

A 2016 study showed that red light therapy helped reduce healing time in knee sprains, hamstring sprains, Achilles tendinitis, intercostal strains (muscle strains), shoulder strains, and foot fractures.

A 2016 study published in Laser Therapy[4] found that red light therapy cut recovery time by half in 395 university athletes with sports-related injuries. In this study, the following soft tissue injuries were treated with red light therapy:

96 knee sprains
35 hamstring muscle strains
30 Achilles tendinitis
26 intercostal muscle strains
20 shoulder sprains
20 abdominal muscle strains
17 foot fractures

Injuries from the 395 athletes occurred during a range of sports, including:

baseball
basketball
crew
cross country
field hockey
football
golf
lacrosse
soccer
softball
swimming/diving
tennis
track & field
volleyball
wrestling

Researchers treated these injuries with 830 nm infrared light.

Female tennis player wearing white, holding tennis racquet in right hand, and holding right elbow with left hand, and has look of pain on her face — Tendinitis responds well to red light therapy

Treatments reduced inflammation and pain, and there were no side effects. Sprains were among the injuries treated. When treated with red light therapy, sprains, and other injuries returned to the field in an average of 9.6 days.

TABLE: Red Light Therapy Helps Athletes Return to Play

Injury	Expected Return to Play (Days)	Actual Return to Play (Days)	Returned to play this much faster with red light therapy
Mild hamstring strain	10-14	7	30-50%
Mild knee sprain	7-10	3.6	49-64%
Severe costochondral muscle sprain	7-14	5.5	21-61%
Severe hip contusion	21-24	12	57-71%
Very severe ankle sprain	28-42	12	57-71%

Several studies show that red light therapy can help with tendonitis. Studies on the shoulder, Achilles heel, bicipital, and eccentric exercise tendinitis show that red light therapy reduces inflammation, shortens healing time, and improves range of motion.

Study #5 Red Light Therapy More Effective Than Naproxen Sodium for Shoulder Tendinitis

Red light therapy reduces pain and improves movement better than naproxen sodium, according to a 1989 study in the Scandinavian Journal of Rheumatology[5] The study tested the effects of 904 nm infrared low-level laser therapy on 30 patients with shoulder injuries, including supraspinatus tendinitis or bicipital tendinitis.

Football player flying horizontally over touchdown line — Red light therapy reduces delayed onset muscle soreness

The naproxen sodium and the red light therapy help with tendinitis healing. Red light therapy participants had greater pain relief and more range of motion improvements than the drug group. The placebo group had no improvements. There were no side effects.

Study #6 Icing Skin Improves Red Light Therapy Achilles Tendinitis Results

Red light therapy reduces Achilles heel tendinitis inflammation, and those results improve with icing the area first, according to a 2017 study published in Photomedicine and Laser Surgery[6].

Icing for 20 minutes before red light therapy produced better results than red light therapy without icing. The 54 subjects received red light therapy, ice therapy, and red light therapy.

man holding red, inflamed knee — Red light therapy helps with acute inflammation.

The red light therapy was either 904 nm infrared “super pulsed” or 810 nm infrared continuous mode therapy. Red light therapy reduced tendon inflammation. Researchers extrapolated how far photons reached based on tendon thickness before and after treatments. They compared the distance light traveled into the injury before and after ice treatment. They concluded that ice therapy improved the distance that photons reached into the injury.

Study #7 Red Light Therapy Improves Eccentric Exercise Tendinitis Therapy

Red light therapy reduces Achilles heel tendinitis healing time, stiffness, crepitation, and tenderness, according to a 2008 study published in The American Journal of Sports Medicine[7].

The study was conducted on 52 recreational athletes separated into treatment and treatment-placebo groups.

Baseball player in red shirt and white pants running to his left with outstretched baseball glove as ball approaches him — Red light therapy provides more oxygen to the muscles.

Researchers combined eccentric exercise therapy with 820 nm red light therapy or red light placebo therapy. The subjects who received red light and physical therapy had significantly less pain than the physical therapy exercise group. Red light therapy significantly improved the subjects’ morning stiffness, tenderness, and crepitation (crackling) over the eccentric exercise-only group.

Conclusion

Red light therapy is proven to speed healing of soft tissue injuries and symptoms such as tendonitis, crepitation, tenderness, and sprains. It is equal to or better than other treatments such as using ice. Athletes return to play faster after using red light therapy on their injured areas.

References

[1] de Moraes Prianti B, Novello GF, de Souza Moreira Prianti T, Costa DR, Pessoa DR, Nicolau RA. Evaluation of the therapeutic effects of led (627 ± 10 nm) on the initial phase of ankle sprain treatment: a randomised placebo-controlled clinical trial. Lasers Med Sci. 2018 Jul;33(5):1031-1038. doi: 10.1007/s10103-018-2460-6. Epub 2018 Feb 8. PMID: 29423840.
[2] Calin MA, Badila A, Hristea A, Manea D, Savastru R, Nica AS. Fractionated Irradiation in Photobiomodulation Therapy of Ankle Sprain. Am J Phys Med Rehabil. 2019 Aug;98(8):692-698. doi: 10.1097/PHM.0000000000001178. PMID: 31318750.
[3] Stergioulas A. Low-level laser treatment can reduce edema in second degree ankle sprains. J Clin Laser Med Surg. 2004 Apr;22(2):125-8. doi: 10.1089/104454704774076181. PMID: 15165387.
[4] Foley J, Vasily DB, Bradle J, Rudio C, Calderhead RG. 830 nm light-emitting diode (led) phototherapy significantly reduced return-to-play in injured university athletes: a pilot study. Laser Ther. 2016 Mar 31;25(1):35-42. doi: 10.5978/islsm.16-OR-03. PMID: 27141153; PMCID: PMC4846838.
[5] England S, Farrell AJ, Coppock JS, Struthers G, Bacon PA. Low power laser therapy of shoulder tendonitis. Scand J Rheumatol. 1989;18(6):427-31. doi: 10.3109/03009748909102106. PMID: 2694356.
[6] Haslerud S, Naterstad IF, Bjordal JM, Lopes-Martins RAB, Magnussen LH, Leonardo PS, Marques RH, Joensen J. Achilles Tendon Penetration for Continuous 810 nm and Superpulsed 904 nm Lasers Before and After Ice Application: An In Situ Study on Healthy Young Adults. Photomed Laser Surg. 2017 Oct;35(10):567-575. doi: 10.1089/pho.2017.4269. Epub 2017 Jun 30. PMID: 28677985.
[7] Stergioulas A, Stergioula M, Aarskog R, Lopes-Martins RA, Bjordal JM. Effects of low-level laser therapy and eccentric exercises in the treatment of recreational athletes with chronic achilles tendinopathy. Am J Sports Med. 2008 May;36(5):881-7. doi: 10.1177/0363546507312165. Epub 2008 Feb 13. PMID: 18272794.