At the other extreme, exercising to treat acute back pain may be equally unhelpful. In one study, recovery from acute back pain was slower for patients who exercised to improve flexibility than for those who gradually resumed normal activity, simply letting pain be the guide for how much movement they achieved. In general, normal activity should be resumed in a gradual fashion as soon as the patient feels ready, reserving therapeutic exercises until after the acute pain has resolved. An incremental aerobic exercise program is less stressful than stretching or exercises strengthening the trunk muscles. Experts suggest that walking, stationary biking, swimming, and even light jogging may begin within two weeks of symptoms, but patients should never force themselves to exercise if, by doing so, pain increases.
People usually recover from a strained back or a mildly herniated disc in a few days.
It may take as long as six weeks, however, to fully recover from back pain, particularly if it is due to sciatica. At that time, if the pain has not been relieved, additional measures may be needed. Exercise appears to be important in treating chronic low back pain. In one study, for example, patients with back pain lasting for an average of 18 months were assigned 8 one-hour exercise sessions over four weeks. They showed greater improvement in nearly every area, including reduced pain and increased capacity, compared to patients who did not exercise.