Straight leg lowering test for ab strength

[foster]

Hi,

I was directed by an acquaintance to ask this question here. My question is regarding the straight leg lowering test. Its it an accurate test of ab strength? Is it an isolated test for abs or are the hip flexors also involved?

Thanks

[Diane]

Hi foster,
Perhaps you'd like to introduce yourself on the welcome (http://www.somasimple.com/forums/forumdisplay.php?f=126) forum. What thoughts do you have re: your own question?

[christophb]

Well, when you say ab strength are you referring to rectus, oblique (internal/external), transversus? Secondly, for what reason are you testing the strength.

[Luke Rickards]

This test is more an expression of motor control than strength. Nick, Jason..?

Surely an ab crunch would be a more accurate test of ab strength?

[Erica]

Hi Foster,
Don't think this is the greatest test for abdominal strength. If you are doing this bilaterally, there is alot of force going through the lumbar spine. I had a patient who was doing this with a pilates instructor and really flared her back and hip up. It seems that the hip flexors are involved eccentrically here. Certainly more of a control issue I think.
Erica

[matt c]

Hi foster, ill put my 2 cents worth in here, not sure bout your use of the word accurate for ab strength, but ill come back to that, its not an isolated test for the abs as hip flexion/ext is involved and hence so are the hip flexor muscles, so "accurate" for ab strength id say no due to other muscular involvement other that purely the abs, id agree with luke and say a more accurate or isolated test of ab strength would be a crunch. Check out the relevant anatomy of the abs and hip flexors and youll find your answer pretty easily. Hope that helps.
matt
:teeth:

[foster]

Thanks for the thoughts and opinions so far. I am a personal trainer. Specifically I've been told it's supposed to be a good assessment for strength of the "lower abs." Are the abs strong enough to resist the pull of the hip flexor into anterior tilt.

I've heard someone else say, "The Double Leg-Lowering test would be more of a test of the iliopsoas muscles, than the abdominals. Since the abdominals aren't hip flexors, they only tense up to stabilize the pelvis, enabling the iliopsoas to do their job."

I know the test is used fairly regularly in the fitness world. Just not sure what to think at this point.

[nari]

Foster,

I'm interested too in the need for ab strengthening. What is the rationale? If it is necessary, crunches would be better than SL lowering and safer. The pelvis can be tilted posteriorly prior to the lowering.... but is it just control you are after?

Nari

[Jon Newman]

If everyone was identically proportioned in terms of the various levers in their bodies, the test might make more sense. Or if it could be demonstrated that the ability to straight leg lower has some other value then I could see including it in an evaluation.

My thoughts on strengthening in general: since we inevitably experience sarcopenia (http://www.somasimple.com/forums/showthread.php?t=4409), it is intuitive (but perhaps wrong) that having a certain amount of muscle in the bank might be helpful as we age, similar to bone bank/osteoporosis construct.

The amount of strength training sufficient for basic function for each person given their innate ability to build muscle and their mature lever lengths is unknown. Even it that information was know, it doesn't take into account other various pathologies and pain experiences which change our ability to generate force despite sufficiently available muscle mass.

Regardless, I feel quite confident that highly functioning people in their 80th decade of life are unable to straight leg lower.

[oljoha]

Hanging leg raises (if performed properly with pelvic tilt using the legs as resistance) is one helluwa good ab strengthening exercise. According to Gilmore - strengthening this area seems to prevent "Gilmore's Groin" in soccer players.

Jon - I recently saw a study where they found that increasing your muscle size was shown to improve your metabolism. From we're around 30 we lose 2.5 kg type II muscle fibers per decade - to which they attributed easier weight gains as we age.

http://www.sciencedaily.com/releases/2008/02/080205121740.htm

On muscles in general - I don't think muscles have the respect they deserve. They are not simply all about moving. They should really be considered endocrine glands.

See research area 3: http://www.cmrc.dk/strategiplan_cmrc_eng_2004_2006.pdf

[Jon Newman]

Hanging leg raises (if performed properly with pelvic tilt using the legs as resistance) is one helluwa good ab strengthening exercise. According to Gilmore - strengthening this area seems to prevent "Gilmore's Groin" in soccer players.

Do you have more of a reference than this?

Jon - I recently saw a study where they found that increasing your muscle size was shown to improve your metabolism. From we're around 30 we lose 2.5 kg type II muscle fibers per decade - to which they attributed easier weight gains as we age.

I'm familiar with the idea that having more metabolically active tissue will result in higher basal metabolisms. How much do you think is enough?

On muscles in general - I don't think muscles have the respect they deserve. They are not simply all about moving. They should really be considered endocrine glands.

I think muscles get plenty of admiration in our culture. I like your idea that they be considered as endocrine glands. Again, how much do you think is enough? For example, does one need to be able to do a straight leg lowering test? I realize that isn't foster's question. In answer to foster's original question I think the answers are no and maybe (but sure the hip flexors are involved). Am I right?

[oljoha]

How much muscle? I say just keep 'em in shape - exercise as many of them as possible. If one need a little more strength for sport or activity then go for that. How much is enough is relative to one's needs.

Don't have any references on Gilmore's. It's probably possible to find some though. I also think doing ab / hip flexor exercises stimulate the vicerals in positive ways .. but that's just a hunch.

[Jason Silvernail]

Hi foster.
I guess my assumption is that you are doing this test in the fitness setting to get some pre/post test results for your client.

I would say that without question the "prime mover" here is the hip flexor group (iliacus, psoas, possibly TFL and rectus fem as well). The purpose of this test is supposedly to determine if the abdominal muscle group is able to hold the spine in a comfortable neutral position while the legs are lowered - the lower the legs the larger the torque on the lumbar spine towards extension due to action of the psoas. I would say that this is more a measure of control than strength - in this case I'm operationally defining strength as being the ability generate force to move a load and control as the ability to generate force to prevent movement in an area.

As others have mentioned the lever arm matters and people with a longer build likely cannot do this at even high levels of fitness whereas a shorter person may be able to do this if untrained.

The concept of the "lower abs" and "upper abs" has been discredited for some time and this is not a useful descriptor in terms of strength or function. I take it your use of "scare quotes" before says you're not sold on the upper/lower ab concept - good.

I would say finding another more functional/useful test to help show progress in a client is a good idea.
You can see my credentials below - and I'll tell you right now I hate "core strengthening" for fitness - I think it's a waste of time and on principle I rarely if ever do any of it personally - what little I do is focused on useful movements for the sports I'm into. I think motor control training for those with pain is a different story but I suppose that's for another thread.
Hope that helps.

[foster]

Thanks Jason. I can definitely see the control aspect of this test. Basically I'm using the test to assess whether more ab work is necessary. i guess my main question is, when the legs are lowered, do strong hip flexors actually help prevent the back from arching? Are the abs even dominant here. I'm not much of a physiology guy but I've had a hunch that most "lower" ab exercises are in fact hip flexor dominant exercises.

[Jason Silvernail]

Well, strong hip flexors would create a force that tends to flex the hip (distally) and extend the lumbar spine (psoas).
The question most people are after is do the other abdominal muscles that flex the spine (rectus ab, obliques, TrAbd) have the strength to prevent the lumbar extension and lower the legs comfortably with a stable spine?
While that's a perfectly fine question, I don't see the value in answering it one way or the other. I mean, what does that tell you?
I'm tall (6 feet 2 inches) so I'll probably never do this successfully due to the long lever arm. Yet I consider myself pretty fit and I do fine at the activities I want to do - so how is this a useful test?

As a trainer, I would think you'd be more interested in how much someone could squat or deadlift or bench press safely and effectively. It would be a better thing for clients to shoot for and I would think they are all much more useful movements from a human movement perspective. Especially the squat.

I mean, you're looking for things to work on to show the client they've made meaningful improvements. I don't think that improving someone's straight leg lowering ability is a meaningful improvement. Can you picture this at the water cooler in the office? "yeah, i"m working with this new trainer. They've got me straight leg lowering to 30 degrees. You know, six weeks ago, I could barely do fifty."
Oooh, impressive. See what I mean?

I'd pick something more useful like the squat, pushup, bench, pullup - something they can see and feel the palpable improvement in. Maybe that's just me...

[toddhargrove]

I agree with many of the other replies and would add the following. Strength can be thought of as a skill, and skills are specific to the task. So, although one might be very good at leg lowering, he/she might fare poorly at various other tests of abdominal strength or function, or vice versa.

[TexasOrtho]

I'd pick something more useful like the squat, pushup, bench, pullup - something they can see and feel the palpable improvement in. Maybe that's just me...

I agree with this. The straight leg lowering test always had me scratching my head. I came into physical therapy from a background in exercise science always thinking there must be some credibility to it if licensed providers were doing it. Turns out this and some other "core" tests have very little specificity or carryover to daily activity.

I'm a big squat or modified push-up advocate (must be something in the CSCS bloodline). This is something the patient can easily measure themselves, and both are pretty functional.

[bernard]

Is it this one?
http://www.topendsports.com/testing/tests/abdominal-strength.htm

If it is the case then I would ask if a single human being uses this kind of movement in his daily activities? :angel:

[oljoha]

Say you fall off a cliff and you're hanging on a branch (cartoon style) - if you're not able to pull up and get to a seated position on the branch it could be useful to be strong enough in your hip flexors / legs that you could get them up so you could rest your arms and hang by the legs while you wait for help to arrive.

I don't think the straight leg lowering test has much value - but I sure think it's useful to be able to do movements you don't necessarily need on a daily basis.

[JasonE]

As a trainer, I feel it's an essentially worthless test, other than to simply see if you can do it. But if you can't, what does it mean? Are you too weak, and if so, where? Or are your antagonists overactive and inhibiting the agonists, and if so which ones?

And so on.

I rarely use any of the standard "fitness" tests. Few have any real meaning or application to my client's needs/goals. Instead, we look at what they need/want to accomplish, and use stepping stones toward those goals as a progressive series of tests that have direct, functional meaning for the client. For example, one recent client wanted to improve her running and upper body strength. She was unable to run for a full mile without pain, nor do a simple yoga Side Plank (AKA Inclined Plane). After a few months she is running 6-7 miles comfortably and can execute complex transitions into and out of Side Plank. Along the way, she worked through a series of performance goals that were more experiential rather than quantifiable.

And I agree with what was suggested earlier: the straight-leg lowering test is better considered an assessment of control rather than of strength.

Last: My oldest client to date is 81. She trained hard for about 6 months and could easily execute the straight-leg lowering portion of a far more challenging exercise. Last time I saw her, she was heading down to the Antarctic to put on heavy gear and do crazy stuff on the ice fields. Tough lady - hope I'm that way at that age!