Red (633nm) and Infra-red (830nm) light are able to penetrate through skin, reaching cells within the body and generating an anti-inflammatory response from these cells.
Red light can penetrate 5-10mm into the skin, reaching capillaries and superficial muscles. Red light on its own is more beneficial for issues that are on the skin’s surface e.g.skin healing or wounds. Infra-red light is able to go deeper and reaches up to 2-5 centimeters. This means it can reach muscles, joints, and bones. This makes it suitable to use infra-red therapy for dog joint pain, for example.
Infra-red therapy works because, in response to the light, the cells receive energy. They absorb light through light-sensitive molecules called chromophores. The chromophores are found in the mitochondria, which are the components responsible for the cell’s energy production. This stimulates the cells to produce ATP, the unit of energy that cells use for all their functions. This increased ATP allows cells to rebuild more efficiently and this is what speeds up healing.