The Sit-up: So Simple, Yet So bad!

I have nSit upo idea how long the sit-up has been around – a thousand years maybe? Whatever it is we’ve been doing it for a long time. I don’t know how many times I’ve heard “I do crunches every day.”, “I’m working my core.”, or “Look at my 6-pack.”. My responses to those statements: “No you don’t.”, No you’re not.”, and “great, do you want a cookie for your efforts?”  The fact is I see so many people “working their core” and the only thing they are doing is making a bad problem worse. Something so simple and you are doing it wrong!

I do not have a 6-pack. I do not have a 12-pack. I have what some may refer to as a party-ball of Guinness Extra Stout. Ask my wife, she will vouch for this sexy, fuzzy pillow that serves as my beer containment center. Despite my rather portly and ovoid mid-section, I know my core is a lot stronger, more stable, and less susceptible to injury than the 24 yr. old fitness geek down the street referred to as Jacked Jimmy. Yeah, that guy with glistening abs, who at every chance will raise his extra tight wife-beater tank top up, ever so slightly, just so he can hear the throngs of women fall unconsciously to the ground. Yeah that guy. How do I know that I can beat him in a core-off? Because more likely than not, he’s doing it wrong. I’ve seen too many “fit” clients fail miserably when I put them through a core routine.

Hip HingeHere’s the problem, we have physical fitness challenges that require kids to do sit-ups. America’s finest heroes (the military for you unappreciative American’s who do not know who America’s finest heroes are) are sadly forced to do sit-ups over and over. When we do sit-ups, we hip hinge.  See the graphic here to the left. The primary muscles activated during the sit-up are rectus abdominus, iliopsoas, tensor fasciae latae, rectus femoris, sartorius, plus a few other small hip flexing muscles. Every muscle I just named is already overactive and their hyperactivity is closely linked to our most common injuries – low back pain, SI joint pain, knee pain, Achilles and foot issues, and even headaches. In addition, the sit-up adds a substantial amount of load to the vertebral discs. These muscles do not need to be activated. We need to turn them off. These muscles are not responsible for enhancing core stability. Read more about these “evil” muscles in my Muscle Battle post.

Stuart McGill, a highly regarded professor and back pain specialist says this on his website“There’s so much mythology out there about the core. The idea has reached trainers and through them the public that the core means only the abs. There’s no science behind that idea.”


Image from

In lieu of the sit-up, do the crunch. The crunch, if you do it right, you will not activate the  aforementioned muscles. By doing the crunch perfectly, you will strengthen the core and simultaneously turn-off the hyperactive muscles. A proper crunch reduces unnecessary hip flexor activation and decreases lordosis by taking out iliopsoas muscle. The crunch flexes at the lumbar spine, not the hip. To the right is a good image for the crunch that illustrates this. Notice how the lower back stays on the ground. The movement occurs at the mid-back, not the hip. Performing the abdominal drawing in maneuver during the crunch will elicit greater transverse abdominus activation as well, which is important when strengthening the core.

What I am simply saying here is that the sit-up is a poor exercise. It does not strengthen the core. Instead of the sit-up, do a crunch as this will better target some of the core muscles. I highlight some because the core is not just crunches and the abs. The core is multidirectional and encompasses all muscles of the trunk, abdominals, obliques, quadratus lumboroum, erector spinae, multifidi and more.

If you are looking to improve your core strength or reduce low back pain please feel free to contact me to discuss options or set-up a free consultation. I offer in person one-on-one training, or virtual training.

7 thoughts on “The Sit-up: So Simple, Yet So bad!

  1. brave but stupid

    So, as a small unit leader in the military I’ve often heard this critique against sit-ups. But to train large groups with minimal equipment they’ve often been seen as a convenient exercise. Besides crunches are there other good body weight exercises that target the true core muscles while avoiding those hyperactive muscles? Off the top of my head I’m wondering about flutter kicks here, but other ideas would be great as well. Thanks much!

    1. Joshua Stone Post author

      Oh my gosh, there are many, but here are a few. I’d do any of these before I did sit-ups.
      Floor bridge
      Prone cobra
      Good Mornings
      Side Crunch
      Push-up with rotation
      Planks (Prone, side, reverse)

  2. Michael Mullin

    Very true Josh. If they could also have their heels hooked onto a strong resistance band and pulling back, that would facilitate hamstrings which would: 1) stabilize pelvis, 2) “isolate” abdominals, 3) provide reciprocal activity for improved function and carry-over. Has been called a “Janda sit-up”, but should be modified to a crunch.

  3. Paul Martin

    I understand everything you’re saying in this post. As a former trainer, this is often what I trained my clients in. Lately, however, and from my experience and the experience I have working with my patients and clients, the crunch has never fully developed any functional abilities that have translated out to the real world. When I teach them how to do a situp correctly, using abdominal muscles in conjunction with the rest of the hip flexors, this translates into an increased ability to sit up. This is a movement that people find helpful in the real world.

    This is not to say that the crunch has no value at all, and if the goal is simply to “strengthen the core” then I’m sure they do. But my goal in training is a translation of that effort from exercise to functional performance in the real world, and I find the situp, when performed correctly, superior to the crunch for that purpose.

  4. Augustas

    What about the so called “Janda” sit up. Is it any good? Is it risky regarding lower back injuries?
    I am doing some product research and do not want to spread the wrong information.

    1. Joshua Stone Post author

      I think it is great of it can be done properly, but so few people can perform the movement without compensation. Even I, who can really focus on getting my glutes engaged have a hard time doing so though the movement. And when the client is not doing engaging, it is hard to see the compensation occuring.last, check the ruin angle, because many have over a rectus that dominates over the obliques.

  5. Augustas

    If i understood compensation process correctly: psoas+iliacus engaged, heels lifted, back arched. Then feet down, back rounded, torso ,,rocks” up. So, maybe attention to keeping the lower back pressed on the ground will improve exercise form? And then, it is no longer a sit up, more like a janda crunch.


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