Why crunches won’t give you flat abs, and will hurt your body


Crunches (and variations of crunches) have long been the most popular tool in the ab-strengthening kit, but that’s about to change.

At gyms and fitness studios around the city, trainers are replacing them with other creative core-training moves. “Planks are the new crunches,” one trainer told us recently.

That’s a great thing, says Brynn Jinnett, founder of the Refine Method. While the moves were supposed to be a safer replacement for the now shunned sit-up, crunches may actually be damaging your body, she says.

Brynn Jinnett

Brynn Jinnett of the Refine Method says there are lots of better ways to strengthen your core than crunches


“You sit all day at your desk, hunched over with rounded shoulders—and then crunches put you into the exact same position and reinforce it,” says Jinnett. That rounded posture can cause all kinds of problems, putting other areas out of alignment.

To add insult to injury, crunches also won’t deliver a six-pack or flat abs, because they only train the forward flexing of your torso, one movement among many that they’re responsible for.

Wait! What about that awesome burn you feel as you curl up for the 50th time?


“The burning you feel with high-repetition, low-weight exercises like crunches is just one of those things that happens. But it’s not fat loss happening, it’s not calories burned, it’s not strengthening—it’s just something that happens,” explains Jinnett. “People are confusing short-term sensation and long-term results.”

So how should you strengthen your midsection?

Jinnett says that you should train your core to “reflexively stabilize in a functional way,” while keeping your spine neutral (not rounded). See her suggested exercises you can do at home—from plank variations to resistance band movements—here.

And about those flat abs: Definition is all about reducing body fat, and since spot burning is impossible, you’ll have to slim down overall in order to get those abdominal “parentheses” to peek out.

“Abs are made in the kitchen,” says Jinnett, “not at the gym.” —Lisa Elaine Held

17 Comments | ADD YOURS

  1. May 14th, 2012 at 11:30 am

    As I always tell me clients, ab training is more for stability then high reps. High reps will simply compress your spine. If you can do more than 10-20 reps, the exercise is too easy and simply becomes repetitive movement. Crunches, when done slowly, in a controlled and focused way, are just fine when combined with other exercises.

  2. May 19th, 2012 at 10:20 am

    Planks are even more useless..it belongs in the junk heap of useless exercises for showing abs right alongside crunches and cardio..its 100% diet..PERIOD!

  3. admin
    May 20th, 2012 at 9:21 pm

    Test comment.

  4. May 27th, 2012 at 1:32 am

    @Sonny, abs are not 100% diet! I’ve been extremely skinny and had zero hint of abs visible, but when I was fuller (had more fat) but worked out, I had some definition.

    Although you need to lose body fat for visible abs, you still need to work them out to actually have abs to see!

  5. June 11th, 2012 at 6:03 am

    You have a good point there! I have been doing crunches for a long time but I also experience back pains. Hhmm this is interesting. I have never tried plank exercises before but it might work. During workouts, I personally recommend a Berlei sports bra because it gives a very good breast compression and the straps won’t hurt your shoulders. You should try it yourself! Great blog, by the way. Love the info…

  6. September 8th, 2013 at 6:22 pm

    I have been doing crunches last year, experienced back pains and then quit. I thought its not my cup of tea. this is wonderful quote you mentioned ” Abs are made in the kitchen, not at the gym”. Thanks for sharing nice post.

  7. saloma
    October 13th, 2013 at 11:48 pm

    i do agree with Brynn Jinnett that there are lots of better ways to strengthen your core than crunches. I prefer yoga in the morning.

  8. November 28th, 2013 at 1:47 am

    I do agree there are lots of better ways to strengthen our core than crunches i have tried prank exercise and it worked for me.

  9. January 4th, 2014 at 4:54 pm

    indeed very scientific: “just one of those things that happen”.

    10 min per day of some exercise will “reinforce bad posture”.. I guess that is why all those fitness nuts that do thousands of crunches have “bad posture”.. NOT.

    Never liked crunches, but I think most people will find that situps are just fine. just place your hands on your chest. most of the flexion comes from your hip if you do it properly

    p.s. if you are experiencing back pain from situps you are probably too weak and/or are not doing them properly..

  10. May 28th, 2014 at 5:40 pm

    hmm…me and my friends train together, eat well, and do hundreds of crunches everyday, and we have solid abs… they didnt just appear from nowhere so i dont get what ive just read here… ive never heard such rubbish

  11. September 18th, 2014 at 10:43 am

    The author has absolutely no idea that the rectus abdominus muscle is only one muscle. You can put emphasis on certain muscle fibers (motor units) but you still work the upper and lower region of your abs !!

  12. September 28th, 2014 at 2:07 pm

    yoga is the best workout for the whole body

  13. September 29th, 2014 at 3:04 am

    Too many crunches will create an imbalance in your core and cause back pain and/or sciatica which is very painful. You need to work the whole core and not just the upper abs. I have not done a crunch in over two years and I have a very nice six pack. Leg raises, planks, kettlebell swings, pull ups, and headstands have worked out very well for me.

  14. October 7th, 2014 at 4:51 am

    The BEST exercise is the one you are willing to do. Just follow a few basic rules: 1-listen to your body, if it hurts, do something else; 2-start with an intensity that equals your current fitness level; 3-remember to ALWAYS stretch Before AND After a workout; 4-don’t forget to factor in recovery time, you can rotate areas of concentration as well as intensity; 5-equipment is all great and good but you should also include activity as part of your workout: swimming, baseball, volleyball, etc.. The more fun and variety you incorporate into your workout, the more you will be willing to continue to workout.

  15. October 29th, 2014 at 6:09 pm

    A combination of a balanced diet and exercise is best. Based on my personal experience crunches only define the upper portion of the abs. Planks are great and tone the entire ab section

  16. Anonymous
    November 8th, 2014 at 9:52 pm

    Interesting post. I do agree Balance diet and exercise is best. Yoga-inspired core exercises can also help.

  17. December 26th, 2014 at 11:45 am

    Can we get off the “crunch-hating” hamster wheel? Crunch is a garbage-pail term anyway; understand what you are doing here (or should be doing)… endurance training for the core. The function you are trying to work here is their holding up of the pelvis to the trunk ( resisting anterior pelvic tilt), as well as locking the pelvis to the trunk…low back (lumbar) should be STABLE for proper functionality. If youre not doing training with this goal in mind, youre wasting your time

Leave a Comment (* required)