The most well studied mechanism of action surrounding red and near infrared light therapy is increased MITOchondrial energy production in the cells. MITOchondria are tiny organelles that are the energy power plants of all the cells in our body. Red and near infrared light therapy helps the MITOchondria create more of that energy.
The specific photons found in red and near infrared light interact with a photoreceptors within our cells called cytochrome c oxidase. This interaction stimulates the mitochondria in our cells to use oxygen more efficiently, which allows the mitochondria to produce more ATP (adenosine triphosphate). Adenosine triphosphate is a complex organic chemical that provides energy to drive many processes in living cells, e.g. muscle contraction, nerve impulse propagation, and chemical synthesis. Found in all forms of life, ATP is often referred to as the "molecular unit of currency" of intracellular energy transfer. When our cells have more energy, they simply perform better and the body follows suit!
Below is a link to a 3rd party compilation of over 4000 scientific studies on Photobiomodulation (PBM) / Low Level Laser Therapy (LLLT).