Don't Put Your Hands Under Your Butt by Stuart MacEwan
Let's chat for a moment about the habit of putting your hands under your butt while doing leg lifts and other abdominal exercises. And by chat, I mean I’m going to tell you to stop doing it. No more hands under your booty. Its lazy, it’s unnecessary and counterproductive. Allow me to explain…
Walk into any group exercise class where leg lifts are being performed and you will invariably see dedicated class members laboring on their lower abs with hands planted firmly under their butts. The general idea is to lessen or remove lower back pain while working the lower abdominal pelvic muscles. And it works to alleviate lower back discomfort right away. Unfortunately it also robs your lower ab muscles of the stress and development you are working so hard to create.
The rectus abdominus (along with the psoas and the obliques) are primarily responsible for creating stability in the body by joining the pelvis to the spine and rib cage. When flexed, the rectus abdominus tilts the pelvis and ribcage together so that they draw each other nearer. When this happens, the opposite side of the torso (the lumbar spine) should flatten or round outwardly. When doing leg lifts, a wear rectus abdominus will tire quickly and lose its ability to bring the pelvis and ribcage together on the front of the torso. This will cause the hips to roll away from the rib cage and the lumbar spine will suddenly follow by bridging, losing its flat supported position. In this position or lumbar bridging, the lower back can quickly feel uncomfortable (largely because the psoas takes over the majority of the torso stabilization and the psoas will complain by aching when it works by itself). The problem here is clearly that the rectus abdominus is under too great of a load and is either weak (requiring greater strengthening) or is tired (requiring rest or greater conditioning). A good solution is to simply raise the legs higher in the air to ease the work on the rectus abdominus and reposition the pelvis so that it is allowed to again tilt forward to the ribcage. Then carefully allow the legs to drop down slowly until the abs begin to fatigue, stopping just short of allowing the pelvis to roll rearward or bridging the back uncomfortably. When performed correctly, the legs should drop just enough to allow the participant to hold a flat spine on the ground and a forwardly positioned pelvis for the duration of the exercise. This will keep the rectus abdominus (along with the aforementioned psoas and obliques) fully involved in the exercise without compromising form or robbing the abs of work by artificially placing support under the hips with your hands. You will know you are growing stronger because over time you will be able to lower your legs closer and closer to the ground without help from your hands while maintaining good pelvis position and a flat supported back.
So stop putting your hands under your butt. You abs will thank you, and so will all the people who shake your hand after class.