How Does Heat Soothe Pain?
There's no doubt that soaking in a warm bath, sipping a cup of hot tea or cozying up in a heated blanket can make you feel instantly soothed. That sudden wave of comfort isn't just in your imagination - heat can actually relax stiff, tense muscles and joints. In fact, many experts recommend trying treatments such as heating pads or hot and cold gel packs for arthritis or to relieve chronic pain associated with minor injuries such as strains, sprains, bruises and bumps.
The question is, how? Here's a look at the science behind heat therapy.
Why It Works
When your muscles feel fatigued or sore, the culprit may be lactic acid, a chemical that is produced when muscles are overworked and deprived of oxygen - for example, during intense levels of exercise. Decreased blood flow to the damaged muscles means that the lactic acid stays in that area. Everyday Health explained that applying heat to an area that's aching it facilitates blood flow to that spot, which then helps remove the lactic acid waste that has built up, thus lowering the pain.
Additionally, boosting circulation to a certain part of your body means you may experience greater flexibility and range of motion. As such, heat is a great way to prepare yourself for physical activity. If you're suffering from an ongoing injury, you should consider using heat therapy on the area before working out, as well as sleeping on a heated mattress pad.
Healthline noted that heat can relax sudden involuntary muscle contractions as well, which is why it's a smart option when you're experiencing back spasms. According to Spine-Health, lower back strain is often a result of over-exertion creating muscle tension, which then hinders circulation and sends pain signals to the brain. Fortunately, heat therapy can dilate the blood vessels around the affected muscles, thus accelerating the flow of oxygen and other healing nutrients to the area surrounding the lumbar spine. Moreover, applying heat to the skin can stretch the soft tissues around the spine, easing stiffness.
A recent University College London study determined that heat is also capable of relieving internal pains as well, such as abdominal aches and menstrual cramps. Dr. Brian King of the UCL Department of Physiology, who led the research, found that heat actually deactivates pain at the molecular level, almost in the same way as pharmaceutical painkillers so. This is because when an object, such as a heating pad, reaches over 40 degrees Celsius us applied to the skin where internal pain is felt, it turns on the heat receptors near that site, which in turn block the chemical messengers responsible for pain detection.