Hey guys, Dr. Lell here. When people want to work their core at the gym, they may start doing crunches (sit ups) on the floor or with a machine. I haven’t been to single gym here in Portland that doesn’t have one of those torture chairs for your abs. Crunches, outside of only targeting one muscle group of your core, have been shown to do a pretty bad job and even do more harm than good.
Why does the crunch fall short?
I know by now someone is saying that you can’t use the words crunch and sit up interchangeably. And that’s true. So I’ll approach each separately in this section. Both exercises only work the rectus abdominis which only represents a percentage of the your core musculature. Different people will have different opinions on what to include when they talk about core muscles. I tend to think of the rectus abdominis, internal/external obliques, transverse abdominis, diaphragm, multifidus, and the erector group. Some people go on to include the lats and muscles, quadratus lumborum, and muscles of the pelvis. Overdevelopment of only one group can lead to an imbalance eventually causing faulty and painful movement patterns.
The crunch is specifically underwhelming because it isolates such a small section of a very large muscle. Without using the entire muscle in its dynamic range, you can’t adequately strengthen it. You’ll recognize this in a lot of people who are always working their core because their mid-lower front stomach will be super toned but the rest is still kind of fluffy.
The sit up gives you more of a range but at the expense of your low back. The forward flexion with increased internal pressure creates the perfect environment for a bulging disc’s last thread to snap.
A good core routine should work most of the core while not promoting injury.
A better alternative
I like to start people off with just two exercises that are plenty challenging and do a fantastic job of toning the core while keeping your low back safe. They’re the plank and side bridge.
This is great not only for the core but for the quads, shoulders, and butt. Rest your weight on your elbows and toes. Your elbows should be under your shoulders. Your legs should be straight and shoulder’s width apart. Lift your butt up until it’s level with your head. You want your back from butt to head to be a straight line. Common mistake include lifting the butt too high or letting it drop – this is cheating and does more harm than good. I like to have people hold it for as long as they can slowly working their way up to 2 minutes. It’s also good to hold for 5-10 seconds and repeat three times until you can sustain it for at least 30s. If you’re more of an A/V learner, check out this YouTube Link. Once the plank can be held for 2 minutes, there are numerous ways to make it more challenging.
The side bridge
The side bridge picks up some of what the planks leave out. Get on your side. Rest your elbow not below your shoulder but a little closer in. Make sure your pelvis is straight (don’t be in the fetal position). Your legs should be straight with your top ankle just in front of your bottom (this is for stability. You can leave it on top if you’d like). Lift yourself off the ground and hold. You’ll notice that in the holding position, your elbow will be right under your shoulder (which is why you start off with it closer in). Try to not let your top shoulder roll over towards the floor – keep everything straight and in line. You can rest your unused arm on your side or reach for the ceiling. The same directions for reps/holding applies. If this is too difficult, you can bend your knees and use your knee as the contact point instead of your feet. If you’d like to see a video, check this out.
For those needing more structure and challenge, there are many good Pilates gyms here in Portland, especially Sellwood, and in Oregon City that I refer people to.
The benefits of a strong core
The core is central to your body and how your move. It should be strong and tight to protect the back, facilitate weight transfer, and allow for optimal motion. When the core is weak and doesn’t offer the stability that the body needs, the surrounding joints (hips and shoulders) tighten up which can lead to injury. I integrate core exercises into my treatment plan for every patient with chronic shoulder and hip issues and I see fantastic results that would not have been otherwise achieved just by treating the shoulder. If you’re doing crunches or sit-ups, try these instead and see how much of a difference they can make!
Until next time, eat well and move often.
Yours in good health,
Questions about this post?
Dr. Lell would be happy to answer questions or provide more information discussed in this blog post. Contact him through our Contact Page.