Red Light Therapy also known as Near Infrared Therapy, Infrared (IR) Therapy and LED Therapy was developed by NASA and is now undergoing an explosive growth phase, as people learn about its effectiveness. LEDs of red to infrared wavelengths stimulate the basic energy proccesses in the mitochondria of each cell. Chromophores and cytochromes inside the mitochondria activate when bathed in red and infrared light, to speed wound healing, and generate other positive musculoskeletal effects. Infrared and near infrared light penetrate soft tissue further than visible wavelengths to stimulate tissue deep below the skins surface. LED treatment accelerates normal healing and tissue regeneration without producing overgrowth or neoplastic transformation. The effects of LED therapy are optimal when cells are in their growth phase, therfore LED therapy is best when administered immediatly after an open wound/cut injury occurs. In studies done on submarine crew members, who operate in low oxygen, high carbon dioxide air mixtures and lack regular sunlight exposure, triple wavelength LED therapy decreased laceration healing time by 50% (7 days down from 14 days).

In addition to its rapid healing effects, Red Light Therapy has been shown to have a pain relieving effect as well.
Recent evidence indicates that the therapeutic effects of red to near infrared light result, in part, from intracellular signaling mechanisms triggered by the interaction of NIR light with the mitochondrial photoacceptor molecule cytochrome c oxidase.

Read More about the uses of Red and Infrared Light Therapy here.
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For more information on the chemical processes of mitochondria I recomend the following links:
Mitochondria Link 1
Mitochondria Link 2(very indepth and technical)
Mitochondria Link 3(very indepth and technical)

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