Heat therapy treatment also called thermotherapy, is the use of heat for pain relief and health. It can take the form of a hot cloth, hot water bottle, ultrasound, heating pad, hydro collator packs, whirlpool baths, cordless FIR heat therapy wraps, and others. It can be beneficial to those with arthritis and stiff muscles and injuries to the deep tissue of the skin. Heat may be an effective self-care treatment for conditions like rheumatoid arthritis. Hot and cold therapy each has their own appropriate uses. You should never apply heat to a joint that is already hot, red, and irritated, for example, nor should you apply cold to a joint that's stiff and not moving well. Therefore heat helps muscles relax and whereas cold helps to minimize inflammation and pain. It's also important to be careful when using hot and cold therapy to manage arthritis pain, or you might end up with damage to your skin from exposure to relatively extreme temperatures. Overworked muscles become sore because of a chemical called lactic acid. Lactic acid accumulates when the muscles are put under stress and deprived of oxygen. When there is decreased blood flow to a damaged area, the lactic acid gets stuck. Therefore treating pain with heat is the best way to deal with chronic pain.