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People who do not exercise face an elevated risk of back pain. A lack of exercise can make your back muscles weak and stiff, restricting movement, increasing stress on the back, and increasing the likelihood of a herniated disc. Exercising will strengthen the muscles that support your spine as well as the muscles in your back, stomach, and legs. It can also help to relieve back pain. Try to get 30 minutes of exercise at least five days per week. You can do anything you like, such as walking, biking, swimming, or dancing. Perform strength training exercises at least twice per week. Choose exercises that target your back, stomach, and legs to increase the strength and flexibility of these muscles, and reduce the risk of a herniated disc. Try partial sit-ups or crunches, pelvic tilts, bridging exercises, and plank exercises.   Crunch. To do a crunch, lay on your back. Keeping your knees bent, raise your shoulders about 3–6 inches (8–20 cm) off the floor, exhaling on the way up and inhaling on the way down. Do this slowly 8-10 times with your arms crossed over your chest.  Pelvic tilt. To do a pelvic tilt, lie on your back with your knees bent and feet flat on the floor. Then, tighten the buttocks and pelvis so that they tip up slightly, pressing your lower back to the floor. Hold for one second and then relax.  Bridging exercise. A bridging exercise is an advanced progression of a pelvic tilt. To do a bridging exercise, lie on your back with your knees bent. Tighten the buttocks and raise your buttocks off the floor. Hold the position for 10 to 20 seconds and lower back to the initial pelvic tilt position. Repeat four more times  Plank exercise. A plank exercise is one of the best exercises to strengthen the core. To do a plank exercise, lie on a floor or bed. Lift your upper body over your elbows while getting on your toes. Hold your body in a straight line and tighten your stomach muscles. Hold the position for 10 to 20 seconds. Lower your body, rest, and repeat four more times. Aerobic exercise increases blood flow to the back, providing nutrients that can support healing. It also increases balance, strength, and flexibility that will help to prevent injuries like a herniated disc. Low-impact exercises also help to relieve existing lower-back pain. These can include swimming, bicycling, elliptical training, water therapy, walking, lumbar extension strength training, and yoga. Aim for a total of at least 150 minutes of moderate exercise per week, such as walking or swimming. If you prefer vigorous aerobic activities such as running or dancing, perform at least 75 minutes of those exercises per week. Some research suggests that certain high-impact exercises eventually raise your risk for a bulging disc. Likewise, improper or overly intense exercise may lead to back troubles. A jerky golf swing or incorrect use of a rowing machine will put extra stress on your spine and, over time, may cause an injury.  Sometimes a small adjustment in form can help. For example, between 30% to 70% of cyclists experience lower back pain, which may be improved by adjusting the seat angle.  You should also avoid exercises that are repetitive in nature and involve a rotation and twisting motion. Some sports such as football or golf can involve these type of movements. This practice will provide your back with additional support and may prevent other types of injuries from occurring. High-heels, for example, can throw off your alignment and increase the risk of a slipped disc, putting particular stress on the lower back.  Consult with the salesperson in a specialized foot-wear or retail store to determine the best shoes for your lifestyle. Custom-made shoes will best address specific gait problems but can cost between $150 to $200.  Running shoes are good for exercise as well as everyday use, as they give stability to your natural arch and provide cushioning -- essential for a healthy gait. New Balance brand is recommended by some doctors.  Orthotic inserts and prescription orthotics are two other options. The latter, called "functional orthotics," are usually made of plastic or graphite and target issues caused in your back or elsewhere through abnormal motion.  Some runners promote so-called "minimalist shoes," which are designed to maximize contact between the ball and center of your foot and the ground, rather than your heel, to mimic bare-footed running. Recent research suggests that such shoes might not be as good for your feet and back as is claimed, however. Excess body weight puts extra strain on your back and spine and can contribute to injuries. Do you have a healthy body mass index? Consult the British National Health at http://www.nhs.uk/tools/pages/healthyweightcalculator.aspx to find out. There are a number of ways to maintain a healthy body weight. Regular exercise is a must. Aim for a minimum of 30 minutes of aerobic exercise like walking, running, or swimming on most days as well as 20 minutes of strength training (like lifting weights) twice a week.  Exercise has to be supported by a healthy lifestyle, including diet. Don’t skip meals, particularly breakfast. Depriving yourself will simply tempt you to binge and slow your metabolism. To keep yourself satisfied, eat 4 to 5 small meals spread throughout the day. Eat plenty of fruits and vegetables, healthy carbohydrates like beans, whole wheat, and brown rice; healthy fats such as nuts, olive oil, and fish; lean protein like chicken, turkey, or eggs; and foods that contain calcium to strengthen your bones. Limit high-calorie foods, sugars, and added fats from fried foods, butter or margarine, salad dressings, or rich sauces.  Eat proper portion sizes. According to the Mayo Clinic, the typical meat portion size is about as big as a deck of playing cards. Fats should be about the size of two dice. For carbohydrates, aim for a portion the size of a hockey puck. Fruit and vegetable portions should be the size of tennis and baseballs, respectively. Smoking tobacco decreases the oxygen flow to your intervertebral discs and prevent them from absorbing the nutrients they need to function normally, causing the discs to degenerate more rapidly and become brittle.. Quitting will have an immediate remedial effect, and will also help your overall well-being. If you are having problems quitting smoking, speak to your health care provider for assistance or for information on joining a support group.

Summary:
Exercise on a regular basis. Perform a variety of strength training exercises. Add moderate aerobic exercise to your regimen, as well. Avoid excessive or improper exercise. Wear proper shoes for any activities you perform. Maintain a healthy weight. Stop smoking.