T Nation

Trying to Find a Peer Reviewed Study...


#1

against spinal flexion exercises (aka crunches).

Here's the deal: I'm currently training with Bad Attitude Gym, a local powerlifting crew, four nights a week, so I have it set as far as workouts go. BUT because I'm a kinesiology major, my University requires me to take this gay weightlifting class and our "teacher" (and I use that term VERY lightly) makes us do all kinds of shit I disagree with such as bosu ball crap and 5-fucking-million variations of crunches which I believe to be bad for your spine. Not only that, I am trying, slowly but surely, to correct my anterior pelvic tilt....lots of sit ups and crunches are very counter productive. My "teacher" is a soccer coach, but she is the type that thinks she is god's gift to all things weightlifting. I already tolerate enough by doing her innefective bosu ball shit, but I'm going to put my foot down with the crunches thing (last thing I want is a herniated disk)

My plan is to print off a couplke peer review studies demonstrating the hazards of lots of crunches then approach her after class, telling her nicely, "I feel crunches are dangerous, here is why, and here are some exercises I feel are better [handing her a print out of Mike Robertson's latest article]).

So, can anybody link me to a peer reviewed article for this? (i've already been searching)


#2

http://www.pitt.edu/~neurolab/publications/1997/BeimGM_1997_JSportRehab_Abdominal%20strengthening%20exercise-a%20comparative%20EMG%20study.pdf
and
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2327580/pdf/canfamphys00191-0133.pdf

Google Scholar is your friend.

Although admittedly, it is difficult to find papers on this topic.

These papers have short lines saying sit-ups are bad for the spine, but aren't extensive studies about that. Maybe you can comment on Mike Robertson's article and see if he has articles.


#3

First up:

Dr. Shirely Sahrmann in her book: Diagnosis and Treatment of Movement Impairment Syndromes, Mosby 2002 states â??during most daily activities, the primary role of the abdominal muscles is to provide isometric support and limit the degree of rotation of the trunkâ?¦A large percentage of low back problems occur because the abdominal muscles are not maintaining tight control over the rotation between the pelvis and the spine at the L5- S1 level. â?? (2002 p.71)

The lumbar range of motion that many personal trainers and coaches have attempted to create may not even be desirable and is probably potentially injurious. The ability to resist or to prevent rotation may in fact be more important than the ability to create it. Clients or athletes must be able to prevent rotation before we should allow them to produce it.

Sahrmann goes on to note a key fact that has been overlooked in the performance field. â??The overall range of lumbar rotation is â?¦approx 13 degrees. The rotation between each segment from T10 to L5 is 2 degrees. The greatest rotational range is between L5 and S1, which is 5 degreesâ?¦The thoracic spine, not the lumbar spine should be the site of greatest amount of rotation of the trunkâ?¦ when an individual practices rotational exercises, he or she should be instructed to â??think about the motion occurring in the area of the chest â?? (Sahrmann, p61-62)

Sahrmann places the final icing on the cake with these statements; â??Rotation of the lumbar spine is more dangerous than beneficial and rotation of the pelvis and lower extremities to one side while the trunk remains stable or is rotated to the other side is particularly dangerous.â?? (Sahrmann p. 72)

Next:

Porterfield and DeRosa- Mechanical Low Back Pain, WB Saunders 1998
Dr.â??s Porterfield and DeRosa in their book, Mechanical Low Back Pain, come to the same conclusion as Sahrmann. Porterfield and DeRosa state â??Rather than considering the abdominals as flexors and rotators of the trunk- for which they certainly have the capacity- their function might be better viewed as antirotators and antilateral flexors of the trunk.â?? (Porterfield and Derosa, WB Saunders 1998, p99)

Need more proof:
According to Dr. Wolf Schamberger in The Malalignment Syndrome: Implications for Medicine and Sport (2002):

â??The facet joints are stressed non-specifically on side bending, back extension alone and back extension combined with rotation to the right or left.â?? (p. 244)

â??Loads on the facet joints of the lumbar spine may play a major role in low-back pain. Shear forces resulting from axial rotation and flexion-extension motions (compressive shear loads) are mainly transmitted through the facet joints.

Although traumatic or transient shear forces will be resisted by both the disc and the facets, the discâ??s viscoelasticity causes slowly applied or constant shear loads to pass through the facet joints.â?? (Hassan A. Serhan, Ph.D.; Gus Varnavas, M.D.; Andrew P. Dooris, Ph.D.; Avinash Patwardhan, Ph.D.; Michael Tzermiadianos, M.D.; Biomechanics of the Posterior Lumbar Articulating Elements, 2007)

This article than goes further into the types of pain caused by facet stress and compression:

â??Facet joint compression leads to at least three causes of back pain: spinal osteoarthritis; bulging and herniated discs; and nerve root impingementâ?¦ Because the nervous system is responsible for many other activities, the effects of facet joint compression are very wide ranging.â??

And one more really good one:

Fact and Fallacies of Fitness (2003)

Dr. Mel Siff thoroughly explains why the prone alternating superman and exercises like it are foolish and dangerous exercises.

â??The combination of lateral bending and rotation constitutes one of the most dangerous maneuvers for the lumbar spine.â?? (p. 89)

Siff than continues to make a very important point and explains why rotary training exercises are much safer and more functional when performed in an upright position

(remember what I said in the last post about how useless seated exercises are- Gordon)

â??A certain degree of compressive preloading locks the facet assembly of the spine and makes it more resistant to torsion. This is the reason why trunk rotation without vertical compression may cause disc injury, whereas the same movement performed with compression is significantly safer.â?? (p. 89)

â??Since the lower extremities are heavier than the upper extremities, this can impose a torque or twisting action around the lumbar spine if the action of the extremities isnâ??t well synchronized and instead of reducing any potential risk of hyperextension, it can add an element of rotation to the extension, thereby making this exercise less safe than controlled gradual simultaneous raising of the legs and arms. In fact, itâ??s not uncommon for this exercise to cause acute back pain and spasm.â?? (Siff, p.36)

Siff then goes on to say that â??Current research has shown that the superman exercise and several of its variations have little or no benefit on back strength and posture.â?? (Siff, p.36)

I hope this info wasnâ??t too shocking, but as you see it is the scientific truth and that is why it is DANGEROUS to get your fitness information from unqualified people and sources i.e. magazines & television!

Gregory S. Kolt and Lynn Snyder-Mackler in their book Physical Therapies in Sport and Exercise (2003):

â??The mechanism of back injury in athletes is normally the same as in the general population (i.e. prolonged and or repeated spinal flexion, flexion and rotation under load).â?? (p. 250)

Keeping Spinal Surgeons is business!

This is the EXACT position and movement of the stupid and useless crunch machines. They place an excessive load on the low back with an improper range of motion forcing muscles whose primary role is to extend the spine into a FORWARD FLEXED POSITION UNDER A LOAD!!! (ever wonder why your low back hurts when you get off the crunch machine?? â?? NOW you now why!)

So here is a great tip for protecting your spine and preventing back & neck pain â?? STAY THE HELL AWAY FROM ANY CRUNCH MACHINE!!! (this includes all the USELESS garbage sold on late night TV).

I know this was a lot to comprehend and many of you may be in shock or refuse to believe what I have written but it is the TRUTH!!

copied and pasted from here :


#4

Thank you very very much!


#5

sorry, I also meant to thank you as well. I appreciate the articles yall sent me.


#6

but she'll still be too dumb to understand or accept any of it though


#7

yeah no kidding. Honestly the hardest thing for me about weightlifting/nutrition/fitness is not diet or workouts, but simply dealing with idiots who teach people all the wrong shit. I then feel obligated to reteach everyone in the class who learned the wrong stuff, but of course they think "what does he know" and listen to the teacher anyways. oihsdvao;iwio;hsfdblhidsfalk gahhhhh people are so annoying.

And last thing....the thing that sucks about the fitness industry is that everyone has such a strong opinion about how to workout but very few actually what they are doing. Would you try to fix a car if you don't know how it works? NO!! so why would you assume you aren't fucking up your body when you workout (assuming you aren't knowledgeable). There is a reason strength coaches go to college! If you don't know the name of the muscles worked or their precise functions or how tweaking the form changes things, then you have no business performing that exercise, let alone teaching it!

I just got back from that class if you can't tell. lol

rant over.