The double leg drop is a great exercise if you're interested in improving core strength. It's not only effective at toning and strengthening the muscles of the core, but can also be a great rehabilitative exercise for people who have recently experienced a lower back injury. Be sure to increase the intensity when the basic version of this exercise becomes too easy.

The muscles that make up the core include the abdominals, obliques, hip flexors and muscles of the lower back. Strengthening these muscles can be especially effective for people who have recently experienced injury to the lower back or pelvic region. In addition, increasing your muscle mass results in a faster metabolism, thereby producing greater weight loss.

Before you perform the double leg drops, it is essential that you position your body properly. Start by clearing out a space on the floor, and place a yoga or exercise mat firmly on the ground. Lay down on the ground with your body in a straight line from the tip of your head down to your feet. Extend your arms out to the sides, making a "T" shape with your body. Carefully bend your knees, lifting your feet off the ground, and extend your legs up to the sky. Try to keep your knees as straight as possible, so you make a straight line from your toes to your hips.

Now that you are positioned properly, you can perform the double leg drop. Start by taking a few deep breaths. As you inhale your next breath, slowly begin to lower both legs down to the ground simultaneously, keeping them as straight as possible. Eventually you will begin to feel your lower back coming off the ground. At this point, stop lowering your legs, and begin raising them back up to the starting position as you exhale. Do 10 sets of this exercise before taking a short break. Do another 2 sets of 10 repetitions of the double leg drops in order to achieve optimal results.

This exercise is relatively difficult, and should only be performed if you have moderate to high abdominal strength. Once the exercise starts to become too easy, there are a number of ways that you can alter it in order to increase the intensity. One easy way to do so is by strapping a set of ankle weights onto your feet. This increases the weight that your muscles must work against, thereby making the exercise much more difficult to perform.