A workout with leg raises yields many benefits to several muscle groups and to your overall strength. Different types of leg raises can be performed to emphasize different muscle groups and gain more definition. The benefits of leg raises start with proper form and technique and finish with regular practice.
Leg raises are typically performed while lying on the floor, hanging from a chinup bar, or a raised curve bar. Each one provides you with different benefits but all help to increase the strength and definition you see in your lower abdominal muscles. None are easy to perform for beginners or those with under-developed abs. It may take several months and many repetitions before you start to see the results.
Abdominal and Core Muscles
The lower abdominal muscles are the primary muscle group to benefit from leg raises. Hanging leg raises fatigue lower and upper abdominal muscles while floor leg raises primarily benefit the lower abdominals. Repetition of both exercises help to increase the strength and definition that you see in your abs and the control that you have over your core muscles. Changing the position of your legs from bent to straight shifts the focus of the exercise and addresses different abdominal muscles.
Lower Back Muscles
Regular performance of leg raises helps to lower your risk for back injuries, back pain and back strain while performing other exercises or routine activities. Though back muscles are not the focus of the exercise, any abdominal and core exercises work to provide increased support for the back. Because the lower abdominals are the focus of leg raises, these exercises also support the lower back and increase your flexibility and strength.
When you perform leg raises while hanging form a chin-up bar or when you support yourself on a raised curve bar, you are also strengthening your grip. Hanging raises require you to support the weight of your entire body with your hands during the exercise, while supported leg raises using a curve bar allow you to use your grip for balance and support.
All types of leg raises increase the flexibility, agility, and strength of the hip flexors. Both bent knee and straight leg raises require hip joint movement. If you have bad hips or arthritis, speak to your doctor about your limitations and receive guidance on how best to perform this exercise.
Leg raises are most beneficial when you perform them slowly. Swinging your legs back and forth creates momentum rather than working the focus muscle groups, so avoid swinging. Also, follow the leg raises in your abdominal and core workout with exercises that work the opposing muscle group -- the lower back specifically -- and stretch before moving to the next part of your workout.