Some people deadlift with hunched backs. No one argues that this is ideal posture. However, it's incredibly common -- and not just among people new to the lift or the gym. Elite national and international-level powerlifting competitors can often be seen with fully extended hips but with remaining lumbar flexion before the completion of the lift.
It really bothers me because I am extremely careful with deadlift form and I have still occasionally aggravated my disc herniation. If I were to get anywhere near these postures at weights near my 1 RM I'm pretty sure the nucleus from L5-S1 disc would not simply herniate, it would come flying out of my spine like a big hunk of snot. I understand that the thousands of reps and millions of pounds that elite competitors have lifted under the watchful eye of effective trainers probably means their body is prepared for how they lift, but what about the noobs?
McGill's "Low Back Disorders..." sheds some light on this subject (see the (rather poor) photo of pg. 105 of the second edition of this book). He brought in a bunch of powerlifters. He measured the maximum flexion of their spine unweighted. This is considered 100% flexion for a given athlete. Then he used several different means to monitor these lifters as they made heavy lifts. In every case but one (which we'll get to), while these athletes may have flexed
their spine (so their spines are no longer in the "neutral" (or standing) posture), they always stopped 2-3 degrees short of full 100% flexion in any of their lumbar joints. OK, so these athletes are so finely tuned that their bodies know exactly how far they can flex and then they flex no more. I doubt the average gym rat or CrossFitter is so self-aware; especially at the end of a wod when completely winded... but it is possible that some people are just naturally more aware of spine positioning that others. And it appears that these people are less likely to become injured.
During the testing, however, one athlete experienced a loss of muscle control in one of the muscles (it's not clear which, and it's not necassarily important) stabilizing the spine. This permitted one lumbar joint (the L2-L3 in this case) to flex to -- and beyond -- 100% flexion. This athlete was injured. This illustrates a couple of points:
1 - It explains how all those hunched backs in deadlift competitions are not constantly injuring people. They probably never reach 100% flexion in any joint, so the soft tissue (ligaments, discs) remains free of acute trauma.
2 - Even if you've gotten away with it before, even trained powerlifters can have a momentary loss of motor control that can injur the spine. This is more likely if you have a 'hunched' spine where there is little room (2-3 degrees!) for error.
3 - This also explains how people hurt their spine doing relatively benign tasks. I 'tweaked' my back one time picking up my toothbrush off the floor! Obviously the loads here are very small, but if there is a momentary loss of motor control, one of the lumbar joints might reach 100% flexion, which results in injury.
Interesting stuff. I've not yet reached the part of the book where McGill will expain how I might rehab and retrain the 'stablizing' muscles of the spine to reduce the risk of 'loss of motor control', especially during hard breathing where these same stabilizing muscles are helping the athlete to breathe. This is howevery the point of the last third of the book. This seems particular relevant to the CrossFitter who is constantly being asked to lift hard, fast and to do so while really sucking wind.
It really bothers me because I am extremely careful with deadlift form and I have still occasionally aggravated my disc herniation. If I were to get anywhere near these postures at weights near my 1 RM I'm pretty sure the nucleus from L5-S1 disc would not simply herniate, it would come flying out of my spine like a big hunk of snot. I understand that the thousands of reps and millions of pounds that elite competitors have lifted under the watchful eye of effective trainers probably means their body is prepared for how they lift, but what about the noobs?
McGill's "Low Back Disorders..." sheds some light on this subject (see the (rather poor) photo of pg. 105 of the second edition of this book). He brought in a bunch of powerlifters. He measured the maximum flexion of their spine unweighted. This is considered 100% flexion for a given athlete. Then he used several different means to monitor these lifters as they made heavy lifts. In every case but one (which we'll get to), while these athletes may have flexed
their spine (so their spines are no longer in the "neutral" (or standing) posture), they always stopped 2-3 degrees short of full 100% flexion in any of their lumbar joints. OK, so these athletes are so finely tuned that their bodies know exactly how far they can flex and then they flex no more. I doubt the average gym rat or CrossFitter is so self-aware; especially at the end of a wod when completely winded... but it is possible that some people are just naturally more aware of spine positioning that others. And it appears that these people are less likely to become injured.During the testing, however, one athlete experienced a loss of muscle control in one of the muscles (it's not clear which, and it's not necassarily important) stabilizing the spine. This permitted one lumbar joint (the L2-L3 in this case) to flex to -- and beyond -- 100% flexion. This athlete was injured. This illustrates a couple of points:
1 - It explains how all those hunched backs in deadlift competitions are not constantly injuring people. They probably never reach 100% flexion in any joint, so the soft tissue (ligaments, discs) remains free of acute trauma.
2 - Even if you've gotten away with it before, even trained powerlifters can have a momentary loss of motor control that can injur the spine. This is more likely if you have a 'hunched' spine where there is little room (2-3 degrees!) for error.
3 - This also explains how people hurt their spine doing relatively benign tasks. I 'tweaked' my back one time picking up my toothbrush off the floor! Obviously the loads here are very small, but if there is a momentary loss of motor control, one of the lumbar joints might reach 100% flexion, which results in injury.
Interesting stuff. I've not yet reached the part of the book where McGill will expain how I might rehab and retrain the 'stablizing' muscles of the spine to reduce the risk of 'loss of motor control', especially during hard breathing where these same stabilizing muscles are helping the athlete to breathe. This is howevery the point of the last third of the book. This seems particular relevant to the CrossFitter who is constantly being asked to lift hard, fast and to do so while really sucking wind.
SOUNDTRACK: Hey it's Christmas Eve and even punks (occasionally) write Christmas songs. Darlington's "X-mas" on the Album "Mess You Up" (BTW, I linked to Amazon to show the album cover which is... um.. confusing, but recommend your local independent record store) is slow but still pretty catchy. I know the feeling of the lyrics, "I need a bottle of holiday cheer..." They also have a good almost-cover of the Rocky Horror Picture Show "Timewarp" song. I saw these guys years ago at Upstairs at Nicks in Philly, bought a 7", enjoyed it. End of story I thought. They were called "Mess" then. Years later, though, I borrowed a bunch of CDs from a friend to listen to while I was re-finishing the basement in my house and was surprised to find that they had changed their name to Darlington. Just another slurred-speach version of TheRamones, but good stuff. Very poppy. Hits the spot sometimes. Like on X-mas Eve.
IMAGE: Taken without permission but with full credit from pg. 105 of Stuart McGill's "Low Back Disorders: evidence-based prevention and rehabilitation", 2nd Edition.
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