They’re not very effective and can lead to back injuries…this works better

There are few exercises as quintessential as the sit-up. Virtually all of us did them in gym classes when we were growing up. Many people still regularly perform sit-ups in an effort to strengthen the muscles of the core (abdomen, sides and lower back). But conventional sit-ups may cause more harm than good.

Recent development: In a report in The United States Army Medical Department Journal, more than half the injuries caused by the Army’s standard fitness test were linked to sit-ups. Various branches of the US Armed Forces are now evaluating the use of sit-ups. So what does that mean for people who need core conditioning in their fitness regimens? Here’s the latest thinking…


Sit-ups not only target mainly the rectus abdominis, the wall of abdominal muscles that bridges the area between the rib cage and the hips, but also make excessive use of the hip flexors to raise the torso up toward the knees. The side oblique muscles and lower back, which are crucial for everyday activities, are left out.

But suppose that you are moving a heavy piece of furniture. Strong abdominals will help, but so will strength and stability in the back, sides and legs—areas that are not helped by sit-ups. You’ll move better—with more balance and power and less risk for injury—when you exercise all the core muscles as an integrated unit.

A real downside: The most common way people do sit-ups leads them to curl their upper body into a “C shape” as they rise from the floor, which puts tremendous stress on the spinal column. This increases risk for disk herniation, back or nerve pain and muscle strain in the lower back.


Based on my research and work as a conditioning coach for athletes, I believe the following exercises are superior to sit-ups because multiple muscle groups are worked together. In general, a healthy adult can do these exercises three or more times a week.

Forearm plank. Known in yoga as the dolphin plank, it is a whole-body exercise that works the core as well as the shoulder girdle, buttocks and legs. A straight-arm plank puts more emphasis on the triceps (muscles on the back of the upper arm) and the shoulders, while the forearm plank also works the core and hips. The forearm plank is a better choice for people with limited shoulder stability or arm strength or who have carpal tunnel syndrome or other wrist problems.

What to do: Once you’re in position (imagine the upper position of a push-up, except that your forearms are on the floor and your upper arms are perpendicular to the floor), focus on keeping your body and head in one straight line looking at a spot on the floor just in front of your hands.Forearm Plank

Tighten your abdominal muscles—this will help you hold the position and keep your back straight. It’s harder than it looks, especially as the seconds pass and you realize how thoroughly you must engage your muscles from your toes to your shoulders to keep from collapsing to the floor. Keep your jaw relaxed, and breathe deeply throughout the exercise.

I try to hold the position for two or more minutes. For beginners, 10 to 15 seconds is about the limit. If you can hold the position with good form for 30 to 60 seconds, you are probably strong enough to try some variations. For example…

While holding the plank, lift one leg a few inches off the floor…flex the foot toward your knee or point the toes backward. Hold for a few seconds. Repeat with the other leg.

Side plank. This variation of the forearm plank is challenging because you support your weight on just one arm, using the oblique muscles in your sides, the deep transverse abdominal muscles and many muscles in the hips, low back and thighs.Side Plank

What to do: Lie on your right side while resting on your forearm. Contract your abdominal, side and hip muscles, and raise your hips off the floor until your body is in a straight line. Hold the position for at least 30 seconds, then lower yourself back down and switch sides. Alternate sides until you have done three on each side.

The McGill curl-up. Developed by the spine researcher Stuart McGill, this movement is an abdominal crunch with a surprisingly small range of motion that works multiple core muscles. In this exercise, you barely come off the floor, and you never force your spinal column into that hazardous “C” shape.

What to do: Lie on your back, with one foot planted flat on the floor and the other leg straight out. Place one hand on top of the other under the arch in your lower back. This preserves the natural curve and reduces spine pressure.McGill Curl-Up

Keeping your neck in a neutral position, contract your abdominal and oblique muscles so that your upper body just comes up off the floor. You may feel your shoulder blades lose contact with the ground, but your back should remain straight while your hands support the curve in your lower back. Hold the position for a few seconds, then lower back down. Do three to five reps with your left leg bent and then three to five with the right leg bent. Try to work up to three to five reps held for about 10 seconds each on each side.

Also: Don’t tuck your chin into your chest during the rising motion, and don’t curl your back or round your shoulders. Keep your upper body in a straight line by activating only the abdominal and oblique muscles. This keeps your spinal column in a safe and supported position, reducing the risk for muscle strain and spinal disk damage.

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