More than 80% of Americans will experience at least one episode of low-back pain during their lives. Here’s how to relieve the pain and prevent it from coming back…

Act quickly. Most back pain is caused by damage to muscle fibers. Frequent causes: Overuse, repetitive motions (a type of overuse) or anxiety, tension or stress. The damage is accompanied by the release of substances that constrict blood vessels and reduce the oxygenation of tissues. Treating the pain can interrupt this chemical cascade. Take an over-the-counter anti-inflammatory medication such as ibuprofen. For mild pain, take 400 milligrams (mg)—you can treat more severe pain with 800 mg, but always talk to your doctor first.

Also helpful: Moist heat from a hot shower or bath. Or you can apply a cold pack to the area for about 20 minutes several times a day. Heat and cold both can be helpful. Use the one that seems to work best for you.

Keep moving even when it hurts. Relaxing and contracting muscles with normal movements—walking, turning, climbing stairs, etc.—will increase blood flow and help the muscles relax.

Caution: I don’t recommend exercise if you have severe pain…a flare-up of sciatica (nerve pain that typically travels down the leg)…or pain from a traumatic injury such as a sprained back. You’ll want to relax and let things settle down before resuming normal activities. See your doctor if the pain persists for more than a few days or the pain is getting worse instead of better.

Treat depression. The more that your pain limits your daily activities, the more likely you are to be depressed. Your doctor can refer you to a mental health professional. Studies have shown that patients who manage their emotions in a healthy way tend to experience less pain.

Change position every 15 minutes. People who spend hours in the same position are more likely to have back pain than those who move around. If you’re in front of a computer all day, get up and walk every 15 minutes.

Lighten your load. I see a lot of patients with “teacher bag syndrome,” pain in the middle or lower back that’s caused by carrying a heavy bag on one side of the body. You can lighten your load or increase your core strength. Preferably, do both.

Strengthen your core. Strong abdominal muscles are essential for treating and preventing back pain. Self-test: Lie on your back with your arms folded across your chest. Try to sit up without using your arms. If you can’t do it, you don’t have enough core strength and should do curl-ups or other core-strengthening exercises.

To do a curl-up: Lie on your back with your knees bent and your hands under the small of your back. Slowly curl your head and shoulders a few inches off the floor. Pause for a moment, then lower back down. Repeat eight to 12 times.

Check your shoes. If you wear the same pair of shoes often and they are more than six months old, the heels and soles are probably showing signs of wear. The uneven surfaces force your body to compensate, which puts unnecessary stress on your back. Get new shoes or have the bottoms replaced every six months or so.