In 2009, an article in "The New York Times" surprised readers by reporting that abdominal crunches, a mainstay of many exercise programs, are potentially dangerous. Crunches are effective ab strengtheners, but they can cause back pain and spinal injury. While the risks of crunches remain controversial, fitness professionals often recommend switching to exercises that target core muscles. The bridge is one such exercise, and it's a good alternative to crunches in your strength-training routine.
Rectus Abdominis vs. Core
Abdominal crunches target the rectus abdominis, a muscle that extends along the front of your abdomen. Crunches give you a "six pack," but they don't provide the well-rounded strengthening that protects your spine and lower back during natural movement and activity, explains exercise physiologist Pete McCall. Safer alternatives focus on strengthening the core -- that is, the full complement of muscles that surround your spine, including the back muscles and the muscles on the side of your torso as well as the rectus abdominis.
Dangers of Crunches
Crunches are potentially risky because they strengthen only one of the many muscles encircling the spine. A short, strong rectus abdominis muscle surrounded by weak back and side muscles leads to back strain and stresses the spine, warns Stuart McGill, a spine biomechanics expert. McGill observes that exercisers who strengthen their abs but ignore their core tend to suffer from back pain. The flexing movement of the crunches themselves may cause herniated discs or other injuries. Personal trainer Jonathan Ross argues that the danger of spinal injury from crunches is overblown, but he too recommends core work and cautions against overreliance on crunches.
Bridge How-To
To achieve a safe, effective bridge, lie on your back with your legs bent and your feet on the floor, hip-width apart and several inches away from your body. Keep your arms on the floor beside your body. Tighten your abdominal muscles slightly, keeping your lower back in a neutral position with a natural slight arch. Keeping your ab muscles engaged, raise your hips until your torso forms a straight line with your legs. Hold the position until it becomes uncomfortable and then slowly lower yourself to the floor. To make the move more challenging, start with your feet together. After rising into the bridge, straighten one leg and hold until fatigued. Repeat with the other leg.
Core Builders
For a strong, healthy core, McCall recommends starting with four exercises: bridge, side plank, front plank and a series of movements called bird dog. After becoming proficient with these, move on to standing core-strengthening exercises, such as a medicine ball series. Check with a trainer or attend a core-focused exercise class for instruction on these advanced moves. If you want to include crunches in your routine, perform them on a stability ball. The ball's yield protects the spine from excessive flexion.
Considerations
While performing the bridge, keep your lower back in a natural position. Do not push your hips higher than the line of your body, as this causes your lower back to arch excessively. Avoid sit-ups, which are even harder on your spine than crunches are. Do not self-treat lower back pain with abdominal exercises. Check with a health care provider first to make sure the routine is safe for you. Stop exercising immediately and seek medical attention if you feel sharp pain or faintness or have trouble breathing.
