Millions of Americans struggle with lower back pain, but many of us aren't sure exactly how to strengthen the muscles that support the lower back. There are many different lower back exercises you can do to alleviate pain, and several don't require any kind of equipment.

This exercise is very simple, and is perfectly fit for beginners as well as advanced athletes to strengthen the muscles of the lower back. Begin by lying face down on the floor with your arms and legs extended straight out from your body. Make sure to keep your neck in a neutral position, as attempting to hold your head up can cause neck strain. Without moving your torso, keep arms and legs straight and lift them up to form a "U" shape. Your back should be arched, and arms and legs should be extended straight out, several inches off of the floor. Hold this position for about five seconds. Return to the start position. This is one repetition. Try three sets of twelve.

This exercise is very similar to The Superman. Begin by lying on your stomach with arms and legs straight out from the body. Raise either your right arm and left leg, or your left arm and your right leg simultaneously. Hold this position for about five seconds. Return to the start position. This is one rep. You can try three sets of twelve for this lower back exercise as well.

This exercise works both the lower back muscles as well as the hamstrings. Unlike The Superman and The Swimmer, hyperextensions require equipment. Luckily, the apparatus used for hyperextensions, the Roman Chair, is a staple in most fitness centers.

Use the Roman Chair by positioning yourself facing forward. Cross your arms or place them behind your head. Gradually lower your upper body towards the floor with your head/neck in a neutral position. Once you are completely bent over, return to the start position slowly. Ensure that you are not arching your back once you return to the start position. This is one rep. Three sets of twleve work for Hyperextensions as well.

The Cobra is a basic yoga position, and is a great stretch exercise for the lower back. Begin this position by lying face down on the floor. Place both of your hands on either side of your body, at about chest level, under your shoulders. Gradually push/roll your upper body up so that your back is arched and your head is facing forward. Hold this position for anywhere from ten to sixty seconds. Slowly roll back down to the start position. Repeat this move three times.

If you're like most Americans, you likely spend plenty of time sitting in front of a computer. Over time, this can lead to chronic lower back pain. Luckily, there are plenty of easy exercises you can do to prevent and/or alleviate the pain caused by increasingly poor posture. Practice these moves a couple times a week and you can sit, stand and exercise more comfortably everyday.