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Brandon Oto
02-02-2009, 03:15 PM
If glute-ham raises are so good for improving hip extension, why aren't we all doing leg extensions to develop beastly hip flexion and powerful quads?

George Mounce
02-02-2009, 03:35 PM
Who said glute-ham raises were so good?

Garrett Smith
02-02-2009, 03:55 PM
Brandon,
I think you've got the wrong analogy, if that's the right term here.

My impression of an equivalent anterior chain exercise to the GHD for the posterior chain would be something along the lines of:
Imagine a flat or decline bench with roller pads in front of the shin. Subject lies on bench in the normal supine fashion. Subject then raises his entire body (straight or nearly straight from knees to head, knees begin at a 90 degree or less angle) around the pivot point of the knee to a standing position (the feet would likely be against the front roller pad and the floor the entire movement).

Sounds hard to me, and would likely be brutal on the knees (assuming one could even lift off!). It would also stress the hips and quads at the same time, unlike the knee extension machine. The shear force from the thigh pad of the knee extension machine would also be gone, as the thighs would be in the air most of the movement.

The mechanical disadvantage of the quads in the movement I described would appear to be pretty outrageous.

IMO.

Brandon Oto
02-02-2009, 04:26 PM
George: lots of strong people seem to like it...

Garrett: I agree that the analogy is missing some elements. If nothing else, in one case you're moving your body (rather than an extremity) and are working the distal connection of the muscle to strengthen the proximal (rather than working the distal to strengthen the distal).

But I'm not sure why it should be that these differences make the exercise pointless. It may be less effective, but just speaking in terms of muscles, are those differences really so vast that the GHR is a great exercise and the leg extension, or something similar, is a useless one?

Because although there are other things going on, in the end the main thing happening in a GHR seems to be that a leg curl.

Garrett Smith
02-02-2009, 04:48 PM
I'd say that my perception of the difference between a GHR and a seated machine leg curl are quite vast, so I would extend that analogy to the exercise I described and a seated machine leg extension.

Moving the distal ends of extremities around the body is (relatively) easy, moving the body around the extremities is (relatively) hard. Compare a decline bench press to a tuck planche. It's not too hard for most anyone to do a BW decline press (and move their arms around their body). It's pretty darn hard for any untrained person to do a tuck planche (and move their body around their arms), which also involves more "body control"--another difference between the machine exercises and the GHR.

If you've done both, you know that there's a lot more going on in a tuck planche than just an upside-down decline BP and a reverse crunch.

That may not be the best analogy, but I hope it gets my point across.

Have you ever had the pleasure of using a GHR? Or done the similar movement on a pad? (http://www.youtube.com/watch?v=trvd6vsIE2o&feature=channel_page) I have, and I find them worlds apart from a simple leg curl.

Brian DeGennaro
02-02-2009, 05:28 PM
I think we already have the equivalent of the GHR: the GHD situp.

Brandon Oto
02-02-2009, 05:55 PM
Could be, Brian. Although seems like we need the range of motion witnessed in the knee flexion of the GHR; in the GHD situp there's no major movement around the hip (because it doesn't bend that way, of course). Mainly just isometric. Garrett's example might be closer.

Garrett: so in your view, the radical difference in efficacy between those two movements (assuming there is one) is the moving-body vs. moving-extremity distinction? That's the difference that makes the difference?

Garrett Smith
02-02-2009, 06:08 PM
If glute-ham raises are so good for improving hip extension, why aren't we all doing leg extensions to develop beastly hip flexion and powerful quads?
Back to your original question, the leg extension does nothing for hip flexion training as the hips don't really move and there is no appreciable isometric load being imposed on them. The point of the leg extension is to attempt to remove the hips from the movement.

The leg extension does build powerful quads, but only in the "leg extension" format. Not very useful IMO--same might be said of the GHR movement. Problem with the leg extension is mainly the shearing force imposed on the ACL towards the top of the movement by the thigh pad. I'm not swayed much by the Cybex pro - leg extension article (http://media.cybexintl.com/cybexinstitute/research/TheTruthOnFitness_LegExtensions.pdf), as I personally know a guy who says he re-tore his newly repaired ACL when his PT made him do leg extensions too heavy, too soon--he heard the POP during the leg extensions!

Cressey's article on Leg Extensions. (http://www.t-nation.com/free_online_article/sports_body_training_performance_repair/the_truth_about_leg_extensions)

I'm not saying the GHR is a crucial part of any programming...I don't have one, and it would be about #200 on the list of things I'd like to get next for my gym (heck, it would take up half the floor space!).

I'm just saying that comparing a GHR for the posterior chain to the Leg Extension for the anterior chain is comparing apples and oranges.

EDIT: Just saw Brandon's last post.

I think the major differences are twofold:
Moving the body around a fixed point is generally harder and tends to come with greater benefits IMO. Hence the difficulty with which men's gymnastics is regarded.
The GHR and the movement I describe involve two major things--first is moving the body around the knee, second is maintaining the rest of the body isometrically through space. Much harder than sitting on one's arse.

Brandon Oto
02-02-2009, 06:38 PM
Back to your original question, the leg extension does nothing for hip flexion training as the hips don't really move and there is no appreciable isometric load being imposed on them. The point of the leg extension is to attempt to remove the hips from the movement.

Ah -- but the whole point of the GHR example is that it seems like training one attachment of a muscle also strengthens the other one. Training the hamstrings via knee flexion -- which nobody cares much about -- also strengthens the hamstrings for hip extension -- which everyone cares about. Shouldn't we be able to apply this lesson elsewhere too?

Anyway, that's not so important. I guess my main point here is that the GHR requires compound stabilization, moves the body, and is safe for the joints, blah blah blah... but in terms of the prime movers, it's still, essentially, a single-joint exercise. So why is it that we've all shunned single-joint exercises from our strength programs, on the principle that they don't contribute to larger compound strength? Within the right context (adequately strong stabilizers and auxiliary muscles, for instance), the entire lesson of the GHR seems to be that this DOES work.

Unless, of course, those other elements (the stabilization element, for instance) are fundamental to the efficacy of the exercise, and without them, there is no benefit. But I don't see why that should be the case. We could all try doing leg curls, to remove those auxiliary benefits and see if it STILL improved our deadlifts, I suppose...

But yeah, my broader point is something like, "are we avoiding curls because they don't make us stronger, or are we avoiding curls because they're not the perfect exercise?"

Steven Low
02-02-2009, 06:39 PM
Hip extension is pretty much THE "athletic" movement. Most people have imbalances with too strong quads as opposed to hams & glutes. Posturally and occupationally related... sitting... + bad movement patterns. Can never have enough glute/ham strength.

Also, anecdotally I've heard leg extensions tend to be... not so great for the ACL.

Dave Van Skike
02-02-2009, 06:51 PM
if a pt is suggesting leg extension or whatever the knee machine is called, forward him my email, I'm casting a snuff film.

for real. that thing is not good for the kneecap at all, there are far safer, better alternatives. ... TKE's for one.

Brian DeGennaro
02-02-2009, 07:05 PM
Not only is the leg extension bad at the top of the movement, but even more so at the bottom. For most people the bottom of the leg extension places a weighted over-stretch on the patella because of the position of the pad and the seat. Notice how when you hook yourself into the machine you have to be sitting up before you get into the reclined position? You can't be reclining in that machine to do anything safely except relax with your leg propped up on the pads.

Also, the GHR on a GHD is a compound movement because it incorporates back, hip and knee flexion. The hamstring raise is a single joint movement. Also the GHD situp is like the anterior chain equivalent of a GHR. At full ROM it does place the hip in complete extension (hyperextension for some) and the knee in flexion. From there it completely closes both joints.

Robert Callahan
02-02-2009, 10:54 PM
If glute-ham raises are so good for improving hip extension, why aren't we all doing leg extensions to develop beastly hip flexion and powerful quads?

Nobody does GHR as a primary exercise for hip extension. They use it as an assistance exercise to help work weaknesses and improve their squat/DL/PC/whatever and the GHR has a decent carry over to those moves so it makes sense. If leg extensions had more functional carry over of strength to hip flexion they may be employed more frequently, but they don't so they aren't :)

-Robert

Patrick Yeung
02-03-2009, 08:51 AM
Im in class right now, so I cant really read all the posts. But ive always seen the sissy squat as the oppisite of GHD.

http://www.exrx.net/WeightExercises/Quadriceps/WTSissySquat.html
*wfs - sorry, forgot*


This seems to be completely quad passed. And quite difficult to perform.

jake oleander
02-03-2009, 05:21 PM
Im in class right now, so I cant really read all the posts. But ive always seen the sissy squat as the oppisite of GHD.

http://www.exrx.net/WeightExercises/Quadriceps/WTSissySquat.html

This seems to be completely quad passed. And quite difficult to perform.

MY KNEES! :eek: lol

you can have that one...ill take my weak quads!

Brandon Oto
02-03-2009, 07:40 PM
That is really freaking cool.

Gavin Harrison
02-03-2009, 10:46 PM
Part of what makes a GHR good is that it uses the hamstring at both ends. I think a lot of folks perform them by first doing a hip extension then a knee flexion type movement. That and I agree with Steven. Also, don't GHD sit ups work the rectus femoris and the abs, kind of the opposite things to the GHR, except it doesn't work the whole quad so much.

Brandon Oto
02-03-2009, 11:32 PM
Yeah. That knee articulation seems important.

Anyone tried those sissy squats? Seem really neat and I agree it looks almost like a mirror opposite to the GHR (although goofier and maybe less safe).

Steven Low
02-04-2009, 12:12 AM
Sissy squats like hindu squats... and various examples of high stress movements like weighted muscle ups & triceps extensions on the elbows especially... are bad for your joints if you're not strong enough to handle them. Be careful! Pain = no no.

Allen Yeh
02-04-2009, 02:01 AM
Yeah. That knee articulation seems important.

Anyone tried those sissy squats? Seem really neat and I agree it looks almost like a mirror opposite to the GHR (although goofier and maybe less safe).

I've used them in the past, never with any weight on my chest , Patrick beat me to it though as when I first started reading the thread the sissy squat came to mind as a counterpart for a GHR.

Brian DeGennaro
02-04-2009, 05:00 AM
When we do do GHD situps we are trying to utilize the rectus femoris because it is a hip flexor as well as knee extensor, hence the powerful kick as we are in the most stretched positition.

Garrett Smith
02-04-2009, 06:07 AM
Brandon,
A machine leg curl is extremely different, neuromuscular patterning-wise, than a GHR. Being strong at one does not make someone strong at the other one (but I'd guess that strength in a GHR transfers a heck of a lot better to a machine leg curl than the other way around).

Also, if you watch the video from Coach Sommer above, his GHR is a compound movement that incorporates a back extension as well. Far thing from a leg curl.

The movement of a low-bar BS and a DL may look similar (minus the bar placement), but their neurological patterning is very different as well.

About the GHD sit-up, the need to consciously "kick" the legs straight to return to the upright position always seemed contrived to me. Yes it works, but my thought is, shouldn't the well-trained athletic person do it naturally? I've never seen anyone do it right their first rep without coaching.

Allen Yeh
02-04-2009, 06:13 AM
Brandon,
A machine leg curl is extremely different, neuromuscular patterning-wise, than a GHR. Being strong at one does not make someone strong at the other one (but I'd guess that strength in a GHR transfers a heck of a lot better to a machine leg curl than the other way around).

Also, if you watch the video from Coach Sommer above, his GHR is a compound movement that incorporates a back extension as well. Far thing from a leg curl.

The movement of a low-bar BS and a DL may look similar (minus the bar placement), but their neurological patterning is very different as well.

About the GHD sit-up, the need to consciously "kick" the legs straight to return to the upright position always seemed contrived to me. Yes it works, but my thought is, shouldn't the well-trained athletic person do it naturally? I've never seen anyone do it right their first rep without coaching.

To play devils advocate on the thing you said last, I don't know many people that were able to just hop onto a GHR and knock out reps correctly?

Garrett Smith
02-04-2009, 07:13 AM
I'd agree with you, Allen. The GHR is a very contrived exercise as well.

Peter Dell'Orto
02-04-2009, 07:55 AM
The GHR is a very contrived exercise as well.

Does that make it a bad exercise, though?

My experience with it has been that it's a great way to train my glutes, hamstrings, and even my calves (from that final "extend on the toes" to finish the movement). I did have to learn to do them correctly, but that applies to almost every exercise I've ever done. My first deadlifts were pretty ugly, too, nevermind my squat.

Maybe I just got off the functional wagon somewhere. I figure any exercise is okay, as long as it accomplishes something you need it to and does it better than the alternatives. The problem with most isolation exercises is that there is a better way to accomplish the same task. That doesn't make them universally bad. Just worth putting at the bottom of the toolbox - if nothing else gets you there, they're still available. You just don't start with them because they're too limited to be the basis of a routine.

Leg extensions seem to be so limited that they don't give you much strength for anything but leg extensions. So I avoid them because they don't do much; it's better to do squats or lunges. It's not that they are isolation, it's that they don't give you much benefit and possibly some problems.

Only my opinion.

Peter

Garrett Smith
02-04-2009, 08:45 AM
Peter,
I agree with most of what you're saying. This discussion is veering off a bit into the whole "functional" thing.

No exercise is inherently bad or useless. Do I think there are many more exercises that are less contrived, more "natural/functional", and in all likelihood more transferable to athletic activities than the GHR (or GHD sit-up for that matter)? Yes. Could it be towards the bottom of the toolbox, assuming I have several hundred dollars to spend on a gigantic piece of equipment that sits far down on the hierarchy? Sure.

Like expensive tools that only have a minimal range of uses, I'd likely go use someone else's on the rare occasion I needed it. I have a 70's era hyperextension / Roman Chair set-up that I bought on Craigslist for $50 that takes up half the space of a GHD that works just fine for what I need it to. Cheaper, pretty versatile, and much smaller footprint.

Many people's toolboxes are too small (see garage gyms), their tool budget isn't that big (heck, a whole set of bumpers and maybe a cheap bar can be had for the price of a good GHD), or their training time constraints don't allow them to utilize many of the tools that sit way at the bottom of the toolbox.

My priorities in exercise selection sit with these starting points:
Feet and/or body are on solid ground (terrestrial-based)
Hanging from something (arboreal-based)
Supporting myself with my arms (could be either)

PL, OL, and gymnastics/calisthenic-based movements typically fit in one of those major categories. Contraptions that hold the body in place (especially by holding the feet), elevated above the ground, do not--hence they fall way to the bottom of my toolbox.

Peter Dell'Orto
02-04-2009, 04:06 PM
Garrett, it never occured to me that you'd been referring as much to the equipment's utility as the exercise's utility. My apologies, and thanks for clearing up my confusion.

Although I think you can do glute-ham raises without the bench. Lucky for me I train at a gym where they have an EliteFTS GHR. They have also rigged up a bench to allow for floor GHRs. Even so I used to train at a gym with no such equipment - we'd do partner GHRs on the floor. So I think of the GHR apparatus as a way to do GHRs better, not do them in the first place.

My exercise selection criteria these days are "doesn't aggravate my injuries when I do it" followed by "gives me a positive, transferable training effect." Otherwise, it's all good. I do prefer exercises where I'm standing up or hanging from things, but I'm willing to entertain anything that works. GHRs work for me, leg extensions don't - the first makes me stronger in other exercises, the second makes me hurt and doesn't make me stronger in anything else. From everything I've read here and in Cressey's article about leg extensions, I'm not surprised at either result.

Blair Lowe
02-05-2009, 12:00 AM
I'm a bit late here but aren't leg extensions typically what we would classify as an assistance exercise? I would label the glute ham stuff as well except far more useful since most athletes tend to be quad dominant and ham weak.

the Sissy Squat. Interesting exercise. It reminds me of going from stand, back bending into a bridge and standing up in gymnastics. Balance might be tougher since it isn't done on the flats of the feet.

Garrett Smith
02-05-2009, 07:47 AM
Peter,
Re: the difference between floor GHRs and the "machine" GHR.

Floor GHRs are much cheaper and more accessible to a larger population. That being said, I don't think flexing/extending the knee while the patella is being pressured against the ground (whether or not on a pad) is a good idea. Sounds like a perfect recipe for chondromalacia patella to me.

If I was going to add GHRs to my routine, I'd only go with the "proper" machine set-up, with the pad sitting on the front of the thighs (no pressure on the patella at all).

Donald Lee
02-05-2009, 11:05 AM
Peter,
Re: the difference between floor GHRs and the "machine" GHR.

Floor GHRs are much cheaper and more accessible to a larger population. That being said, I don't think flexing/extending the knee while the patella is being pressured against the ground (whether or not on a pad) is a good idea. Sounds like a perfect recipe for chondromalacia patella to me.

If I was going to add GHRs to my routine, I'd only go with the "proper" machine set-up, with the pad sitting on the front of the thighs (no pressure on the patella at all).

I used to do it on the ground with a funky setup. I loaded up a bar with 45's and some extra. I put some weights under it to keep the bar from moving from the wall. I wrapped 2 towels around the bar and had 4 mats to put my knees on. The setup worked just fine. No knee pain, except it's a hassle to setup, so I've stopped.

I also used to do it on a seated calf machine, which did cause some knee discomfort.