The reasons for low back pain are manifold and a doctor should be consulted, if it is more than just muscle ache after unusual activity.
In most of the cases back pain is a result of heavy and unusual physical activity. The medical term for muscle pain is myalgia. Muscle pain of the cervical spine with headaches, stiffness of the neck and diffused radiating pain in shoulder and arms often occur after driving a car for hours, after a hike in the mountains of tourists in the holiday or after refurbishing the flat by an office worker.
Acute muscle hardening of the lumbar spine after unaccustomed labor in bending position or heavy lifting is well known. The less the muscle are trained the less are they protected, i.e. the more likely and they will react with strong muscle pain. But aching muscles are not a sickness, the pain just indicates that the person went over his capacities and is a warning signal. In addition it indicates a restriction in posture and movement.
Acute myalgias normally disappear within 3 to 7 days. Noticeable improvement is promoted by heat, warm bathes, careful massage and relaxation. When the acute muscle ache is over the capacity should be improved by careful training corresponding to strength and age. If no improvement is achieved, a doctor should clarify if there is a pathology.