When you perform leg raises, your abdominal muscles work with your hip flexors. Your abdominal muscles work to keep your pelvis stable, while your hip flexors work to move your legs. This is actually an important motion to master, but here are the problems that may arise.

Problem #1: Your Abdominal Muscles are too Weak to Keep Your Pelvis and Lower Back Stable!

Our legs are heavy, so our abdominal muscles must work really hard to keep our pelvis and lower back in the correct position. As the legs lower towards the floor, there is a tendency for the lower back to arch. When the lower back arches, there is extra pressure placed on the joints of the lower back. The job of the abdominals is to stop the lower back from arching excessively, so if you have weak abdominals you will likely have extra pressure on your lower back when you perform leg raises.

Ab Workout Tip: You can build up your abdominal strength and protect your lower back by limiting your range of motion during leg raises. Begin with your hips at 90 degrees. Lower your legs until you feel your pelvis tipping and your lower back arching; at that point reverse directions and return to the starting position.

As you move closer to the floor more pressure is placed on your lower back so limit your range of motion and move only as far as you can control.

Workout Tip: If you have trouble keeping your legs straight in the air, it is likely a sign of poor flexibility in the hamstring muscles. Stretching your hamstrings can improve your form during this ab exercise.

Workout Tip: If you have any trouble performing leg raises, begin by mastering reverse crunches. Reverse Crunches can help to strengthen your abdominal muscles and increase the flexibility in your lower back, and they are a great exercise for beginners and athletes.

Problem #2: You Have Bad Posture and Bad Alignment in Your Spine!

Here are 2 simple statements about posture. When your posture and alignment are ideal, you have the least pressure on your lower back and the most stability. And, when your posture is not ideal, you have more pressure on the joints of your lower back and less stability in your lower back. Bad Posture adds pressure to your lower back.

Problem #3: Your Hip Flexors add Pressure to the Joints of the Lower Back!

When the legs move during ab exercises, the hip flexors contract. When the hip flexors contract, pressure is added to the lower back. This is a normal process, and this happens during every exercise and at every joint.

But if you have joint irritation in your lower back aggressively working your hip flexors can add excessive pressure to your joints. This problem is really only a problem if you have lower back injuries.

If you have weak abdominals, poor posture, and a lower back injury, then, full straight leg raises all the way to the floor are probably not the best ab exercise for you. If you are a beginner, start by practicing the drawing in maneuver and the plank exercise. Then, move on to reverse crunches and regular crunches. Once you have mastered the basics, it is okay to progress to leg raises and more challenging ab exercises