Burning lower back pain can be caused by several factors, some more severe than others. Nerve damage may result in a burning sensation, or even a "pins and needles" sensation. Such nerve damage may occur because of an injury or impact, or because of compression on the sciatic nerve. Other burning lower back pain may occur because the muscles in the lower back are tired and tight. Stretching can usually alleviate the pain in this case, though sometimes tired or overworked muscles accrue lactic acid, and this type of burning lower back pain can be alleviated by drinking plenty of fluids, stretching regularly, and eating a healthy diet.
The sciatic nerve runs from the lower back into the back of the legs, all the way down to the ankles. When these nerves get pinched, they can cause a sharp, shooting pain anywhere in the lower back, hips, or legs, or caused by a burning lower back pain. Stretching and exercising can often alleviate sciatic nerve pain, though in more severe cases, surgery may be necessary. Sciatic pain can be caused by tight muscles, but it can also be caused by more severe conditions such as herniated discs in the spine, a slipped disc, or a spinal deformity. These are more serious conditions that should be attended to by a doctor.
After intense athletic activity, lactic acid — a byproduct of used glycogen — can build up in the muscles. This buildup can cause a burning lower back pain, alleviated simply by resting, stretching, and drinking plenty of fluids. Lactic acid can build up during and after physical activity that the body is not used to, as well. Heavy lifting, for example, can cause such burning pain if the person doing the lifting has not done so frequently or recently.
Sitting or standing for long periods of time can lead to muscle fatigue. Muscles tend to tighten when they tire, which can cause pain in the lower back. The muscles essentially hold in one position for a long period of time, and when they finally release, they tighten, causing burning lower back pain. To counter such pain, one should be sure to sit for a few minutes at a time if standing for most of the day, or get up and walk around periodically if sitting for long stretches of time. This allows the muscles to remain limber, and it prevents them from tiring too quickly.