Straight legged situps

[fa_jing]

Anyone know anything about straight legged situps? The are supposed to hurt your lower back, but I don't find this to be the case. In fact, it is easier to keep your hips aligned. How do these differ from the bent legged variation?
-FJ

[anerlich]

If you are doing straight legged situps in an attempt to condition your abs, you are exercising very inefficiently.

The abs have nothing to do with bending the body at the hips, but rather to pull the rib cage and pelvis closer together.

Straight legged situps make use of the hip flexor muscles (iliopsoas etc.) and tend to place a lot of stress on the lower spine. If your hip flexors are reasonably flexible, this may not be a problem, but for a person with tight hip flexors consierable stress (compression and shearing) may be placed on the lower spine.

This stress and the associated injury risk can be totally avoided by bending the knees, with no penalty to the effectiveness of your workout on the abs.

Crunches and hanging knee raises (or leg raises with a bend at the knee) are generally regarded as much more effective exercises for the abs.


In fact, it is easier to keep your hips aligned.

Keep them aligned for what? If you want to work abs, you need your lower spine rounded and lower pelvis tucked under. This is much harder with straight legs.

[ElPietro]

Part of my MA training involves straigleg pushups...I have tight hip flexors which aren't at the greatest level of flexibility...I don't feel anything being contributed by the hip flexors. I feel a good burn from my abs when doing straight legged situps...I don't feel any stress anywhere on my back when doing straight legged situps...in fact I find less stress overall...so basically I FEEL that the opposite is the case on almost everything anerlich said. I don't see how it works the hip flexors more...your hips aren't really moving any more or any less than if you had your legs bent with your feet on the floor.

This is just how I feel so maybe I'm just a weird exception, and everyone else feels the exact opposite...just thought I'd add my two cents.

[fa_jing]

I agree with ElPietro, although I have only just begun to use the straight legged variation. Yes Anerlich, you need the lower pelvis tucked under (the opposite of sticking out your butt, right?)
I find that the lower pelvis tucks under just fine with the straight leggers. Also, you are right that the spine must be rounded and about the action of the ab muscles. But this doesn't really have to differ between the straight and bent-legged variations. The important part is in the mechanics of the upper body which must "crunch" in order for the abs to be worked.

-FJ

[anerlich]

Unless you have very non-standard anatomy, you MUST use your hip flexors to bend at the hip joints while doing situps, whether it FEELS that way or not. This is a basic anatomical truth.

By bending your legs, you reduce the ability to involve the hip flexors, both isolating the abs more and reducing the spinal stress. You probably CAN do straight leg situps and just recruit the abs, but why not just bend the legs and take the demand for such strict attention to form out of the equation? To make it more technically difficult than it needs to be just to prove a questionable point?

If you want to go ahead with straight leg SITups, go ahead, but you are going against the opinions of the majority of sports scientists and anatomical science.

It's your spine, do what you want, but if you are so sure there's nothing wrong, why ask for opinions that you don't seem to want to hear?

You guys might want to check out the Abdominal Training FAQ at

http://www.timbomb.net/ab/ab-top.html

specifically, "What's wrong with situps" in the TOC.

You might also want to do a web search for Janda situps, which take the idea of ab isolation and non-recruitment of ther hip flexors even further.

There's no point if your mind is already made up, I guess.

[prana]

yup keep it bent, not straight.

Hmm isn't it true that the most difficult situps have the feet right up against the glutens ? hands touching the forehead and lower back not touching the ground.

[anerlich]

yup keep it bent, not straight.

You got it.



Hmm isn't it true that the most difficult situps have the feet right up against the glutens ? hands touching the forehead and lower back not touching the ground.

I could see that would be difficult, but you need your lower back rounded to recruit the abs. It would need to be on the ground.

The most difficult (and beneficial) "situps" are arguably Janda crunches. Here's a link for anyone who hasn't already made up their mind:

http://www.testosterone.net/html/body_96ab.html

[IronFist]

Unless you have very non-standard anatomy, you MUST use your hip flexors to bend at the hip joints while doing situps, whether it FEELS that way or not. This is a basic anatomical truth.


Can I disprove your "basic anatomic truth?" Do a search on Janda situps :) Actually, I'll save you the trouble. Janda situps are a type of situps that activate the hamstrings, therefore DEactivating the hip flexors, which forces you to use JUST your abs to do the situp. It's bloody hard at first, because no one is used to doing situps without their hip flexors at least a bit.

But you're right, that standard situps use the hip flexors.

Iron

[hkphooey]

hmmmm.... i'm not sure how comfortable i am with the word "deactivating" though iron. does the Janda sit up reduce the work of hip flexors?? absolutely!! even to a great extent. but i am skeptical as to whether it COMPLETELY eliminates the hip flexor. it seems to me that to raise the back completely off the ground requires at least a LITTLE use of the hip flexors, as the movement involves bending/flexing at the hips...anatomically. using reciprical inhibition (via hams and glutes) to de-emphasize the hip flexors transfers most of the work to the abs, but i don't think the abs are "set up" to do the work completely unassisted.

i'm trying to say i think you're both correct...depending on how one defines "using the hip flexors".

[ElPietro]

Isolation exercises are overated anyway...

[anerlich]

Can I disprove your "basic anatomic truth?" Do a search on Janda situps Actually, I'll save you the trouble. Janda situps are a type of situps that activate the hamstrings, therefore DEactivating the hip flexors, which forces you to use JUST your abs to do the situp. It's bloody hard at first, because no one is used to doing situps without their hip flexors at least a bit.

You may have noticed that I already posted a link to Janda CRUNCHES.

And you haven't disproved anything. Janda crunches do deactivate the hip flexors (read the article whose link I posted), meaning you can't flex your hips but only CRUNCH at your waist using your abs. If your hip flexors aren't activated, you can't flex your hips (a tautology as well as a basic anatomicAL truth).

hkphooey, I agree with you.

[fa_jing]

Chill out, man. I appreciate your info, I just took issue with your statement that straight legged situps completely ignore the abs and that the hips couldn't be in the right position. I think it is possible to get around this by using correct body mechanics. Basically, I do the situps the normal way, but I tried straight legged and it seemed cool, I want to do it this way sometimes. It used to be that this was the standard way to do situps, I doubt they're really that bad for a person without pre-existing lower back trouble. Now I looked at the Janda link, he's saying that CRUNCHES are crappy. I probably agree, I only do these after I can't continue with the full situps. But it shows you how opinions change.
I think I'll continue to do straight leggers occasionally, while being careful to take your comments seriously and paying attention to my body mechanics.

-FJ

[anerlich]

Fa-jing:

No sweat. I enjoy an argument perhaps more than I should.

Do what works for you, good luck with your training. Peace, out.

[Kristoffer]

I use them and they have not had an bad effect on me.