Sit-ups Build Legs

Sit-ups build legs, not abs    

Seriously you may challenge me on this but I want you to think about it. How many times did you do sit-up or decline sit-ups and have to stop do to your abs burning so bad? Honestly, I can admit very few really do experience an extreme ab burn during decline sit-ups, in fact most probably notice that their hip flexors start burning more than anything.


What you didn’t know about the Hip Flexors

First off your hip flexors are NOT just one muscle they are a group of muscles that are responsible for flexing the femur (thigh) towards the torso, think of bringing your knees towards you.Hips Flexors and and sit ups - Fitness Revolution Rowlett

If you were to look at the image to the left these are ALL the muscles of the hip flexors… if you notice that the abdominal wall is NOT one of them.

These are the PRIME movers in decline sit-ups and most other sit up variations.

So doing countless reps and decline angles only further continues to improve the functionality and muscular development of the hip flexors, not develop the abdominal wall.

In addition to this I have seen this further tighten the hip flexors more than what most need. Guys I hate to say this but your hip flexors are probably tight enough as it is and they don’t need any reaosn to get tighter, if they do they will just hate you for it.

What ends up happening it that as they tighten up even further they begin to pull your hips down towards your knees and if you think you have hip problems now just wait till those things get tighter.


But you still feel your abs?

This goes back to a previous blog where I talked about learning the difference between contracting your abs vs. flexing them. When you are doing a sit up your abs are CONTRACTING meaning they are bracing vs. FLEXING where the ends of the muscle are shortening together.

When you are doing the sit-up the abdominal wall is contracting or bracing and holding the upper torso ridged so that your hip flexors can move your body easier;  the abdominal wall is NOT shortening or the ends coming closer together.

Don’t get me wrong though even when your abs are having to brace the torso they ARE working and you will notice some development but you may not get the development that you were seeking.


But what about boxers and their abs?

Well its makes complete sense that a boxer would want to do sit ups since it does train the core to brace for an impact of a punch. In their sport they really are not too concerned with the aesthetic appearance of their abdominal wall but more along the lines of functionality if they can take a punch to the gut without keeling over.

No matter what most boxers and fighters do have well developed abdominal walls due to the constant work they put into training, but if you ever look at a boxer or fighters routine there is a LOT more they do for total abdominal function than just sit-ups. In addition they are typically pretty lean due to the strenuous workouts they do AND cutting all the body fat to make weight.Frank Zane and Sit ups - Fitness Revolution Rowlett

Some bodybuilders have also had SOME benefits to doing lots of decline sit ups. The one the comes to mind the most is Frank Zane and even commented that to bring up certain muscles in his waist he did a TON of sit up work and variations. The kicker is thought is that he commented that he thought his waist was TOO small so sit-ups help bring those muscles up. Hmmm… sounds like the complete opposite of what most people are wanting

Also I have found that power lifters can benefit form this exercise because they HAVE to brace their abs for all of their lifts. Having a strong core just helps keep these guys stable when they are squatting or deadlifting those extreme amounts of weight.


What else should I do instead?

I’m not saying take out sit-ups completely but don’t be surprised when you’ve put in your dues in the gym and you don’t get the results that you want.

Some personal favorites of mine are that develop the abdominal wall:



Band Ab Pull Downs

The reason I love this exercise is that it forces you to work the abdominal wall in a way that most people dont think about… standing up. If you think about it how many times are you actaully lying down and doing a full sit up and leg raise? (for some strange reason I feel that people’s minds just went into the gutter lol). A number of ab movement involve you laying down but I train majority of my client’s ab work standing and the band crunch is an amazing way to do so. Give it a shot and I promise you’ll feel a difference.

I will say to get the most out of this make sure that you try to sit down as low as you can to get the maximum benefit. Try to think of doing a crunch first THEN using your abs to pull yourself all the way down past your hips.



Hanging Leg Raises Toes to the Bar

If you have a hard time with this refer back to this previous blog for alternatives but when you bring your toes all the way to the bar you pelvis has to roll forward and up, to do so your abdominal wall MUST flex. Lower down with control and repeat until your abs are mad at you, trust me you’ll know 😉




I learned this one back in gymnastics and it still is one of my favorites and pretty much the ONLY ab exercise that I do lying on the floor. In its most basic form all it is is a lying leg raise and crunch but just done at the same time. Don’t get discouraged if you find this difficult and the timing feels wrong, it happens to everyone their first time. Just keep working on it and I promise you’ll feel it pretty quickly.



Inversion Boots Inversion boots - Fitness Revolution Roweltt(not for the faint of heart)

Honestly I can’t find a video that really does a good job demonstrating these without making them look ‘gemicky’ but I can say from personal expierence, if you want to feel a whole new level of hard when it comes to abdominal training give these a shot. Promise after that head rush you get you WILL feel your abdominal wall.

Side Note: You may see a lot of these used for spinal decompression and this is an excellent devise to do so… if your having a hard time thinking of what spinal decompression is think of the infomercial of Teter Hang-ups.




Starting on Monday

Again I’m not saying that sit-ups are not an exercise, they most certainly are, but if your looking for a well developed midsiction then these may not be yoru best bet. I will OCCASITONLY put these in a clients routine if I see they need some heavy abdominal bracing work, think of the power lifter example we talked about earlier, but majority of the time I stick with a LOT of rotaitonaly based movements OR the movements that you see above.

Give it a shot and tell me what you think!



In Health and Awesomeness,

Travis Signature 300x62 Scary Stuff

Travis Merritt, BS, CPT, CES, RBT is the owner of Fitness Revolution in Rowlett, TX.

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