Subject: ABDOMINAL TRAINING, POSTURE & FUNCTION From: Paul Chek Date: Sat, 10 Jan 1998 20:13:31 -0800 I (Paul Chek) would like to make some comments on the following posts that may bring some clarity: > >Scott A. Shalkowski wrote: > > > Had an interesting conversation with my physio last week and thought I > > would pass on a couple things for the group's interest/discussion. > > I found a few of your physio's comments of interest, so I'll make some > comments for the interest of discussion. > > > He said that the next few years will see another revision in > > what fitness trainers recommend. He said that the medical community is > > currently reverting back to previous opinions--that sit-ups and crunches > > with bent legs instead of straight legs (i) put more stress on the lower > > back, not less, > > Anatomically speaking I don't see how this statement could be true. During > a sit-up the iliacus & psoas muscles are primarily responsible for the hip > flexion moment. Flexing the hip (resulting from the bent knee position) > would if anything acutely decrease the strength of these muscles due to the > length-tension principle. If these muscles can't pull as hard how could > they put increased stress on the back. If you have time, ask your therapist > what particular type of stress he is referring to. Is he suggesting that > contraction of the iliacus puts a pathological stress directly to the low > back or is the psoas putting a stress on the lumbar region secondary to its > pull on the pelvis. Either way, the bent knee position will decrease the > strength at which both these muscle can pull. Bending the knees would > increase the tension on the rectus femoris muscle but the subsequent hip > flexion would cancel out most if not all the increase in tension. > > Crunches will more or less isolate the abs and the hip flexors will not play > a part in the movement. Bending the knees and thus flexing the hip while > lying supine will again decrease the tension through the iliacus and psoas > muscles, which if tight would decrease extension forces of the lumbar spine. Paul Chek Response: First of all, be careful about what the "medical community says about anything!" I was interviewed about my opinions on abdominal gimmicks by the San Diego Union Tribune news paper a couple years ago. They were shocked at what I had to say and when the article came out, they had interviewed the inventors of the Ab Flex. The Ab Flex people, who took a beating by functionalists like myself lashed back by stating that "our product was tested by a group of medical doctors" and is proven by EMG to give the best abdominal workout (paraphrasing here). The fact is, the magnitude of EMG response has little to do with the value of the training. Sitting in a chair, tightening your abs as you drive a spring loaded shaft into your stomach is great training for "sitting in a chair and driving a spring loaded shaft into your stomach", regardless or the EMG reading! Crunches have limited value as well, and certainly are antagonistic to the maintenance of good posture. I clearly demonstrate this in my seminars titled Scientific Abdominal Training and Scientific Back Training (see web page for next location) with case histories and objective measurements. Several years ago I invented and patented a caliper that very accurately measures forward head posture. I have measured thousands of athletes and non athletes alike, conclusively finding increased forward head posture in those performing crunches regularly; the magnitude of their forward head posture increasing in close proportion to their crunch exercise volume. I also invented another caliper which measures the inclination of the first rib. The same finding can be seen in the angle of the first rib; the greater the crunch volume, the greater the first rib angle. First rib angle is much more of a problem for females, who have a far greater incidence of thoracic outlet syndrome and carpel tunnel syndrome than men. This is relevant here because females are some of the most addicted crunchers on the planet, yet anatomically are predisposed to greater incidence of orthopedic disorder as a result. I expand greatly on this topic in my upcoming seminar titled "Training Jane, Not Tarzan." Now that I have led you around a bit, I will go back to my original point, the medical community is not the place to go for reliable information on exercise in many instances. I believe this is because most medical practitioners are trained to study things in isolation, "twitch rate of isolated white fibers in field mice", is an example commonly seen as a medical research paper. This kind of stuff becomes the genesis of how Mr. Soccerboot trains his high school soccer team after being digested by junior Einsteins (most often with good intention). The fact is that the human body is an integrated, "cybernetic" system, or system of systems. Isolated movements have specific applications: hypertrophy training for the injured, those wanting to develop for aesthetic purposes, athletes needing more muscle mass in a base conditioning phase (covered in greater detail in my Program Design and Advanced Program Design Seminars). As for the stress on the back during a crunch: There is a great deal of variation in the magnitude of this stress. The stress this Physio is referring to is mostly anterior sheer force on the lumbar spine created by the psoas. This force can not amount to much unless the feet are anchored. If the feet are not anchored and the psoas is activated, it is easily seen as hip flexion. If the feet are anchored during crunch movements, as one fatigues there is an overwhelming tendency to activate the hip flexors in assistance; this is how the body works. If the hip flexors are activated in concert with poor stabilizing recruitment and thus poor function of the lower abdominal musculature (predominantly external obliques, some internal oblique in this instance, see above reference), there may be "huge sheer forces on the lumbar spine" as indicated by Bogduk in Clinical Anatomy of the Lumbar Spine. In a traditional sit-up with the legs more naturally outstretched, the sheer force is reduced because as the hip joint opens, the line of pull of the psoas creates "compression" on the lumbar spine, which helps stabilize against any sheer forces created. Additionally, as the hip angle closes in a traditional sit-up, inertia has been broken and the body has velocity, reducing the magnitude of sheer force on the spine as the line of pull is more favorable to create sheer. This problem would be reduced if people would quit trying to do sit-up marathon training? Do they still think you can burn fat this way?? > > (ii) serve to shorten and tighten hip flexors, > > Perhaps, if you remained in this position all the time. While the strait > leg version would work the hip flexors through a longer range of motion > (which is desirable) I can't see it causing a lack of flexibility, because > as soon as you stand up and walk away you would stretch out the hip flexors, > at least to the same degree as a strait leg sit up would do. Performing > exercises through a greater range of motion is often desirable for several > reasons, but for this specific example, I feel other daily activities would > prevent a shortening of these muscles. > > > (sometimes resulting in knee pain and wouldn't have otherwise occurred > > and _partly_ accounting for the 'hunched over' problem some bodybuilders > > have), > > You would have to ask you physio about this, but I am guessing that he is > suggesting that a tight rectus femoris muscle could increase patellofemoral > compressive force (which it may), however, again while flexing the knee > during a sit up would stretch this muscle, the subsequent hip flexion would > again shorten it. Also, I have never noticed that bodybuilders walked > around hunched over, at least not at the hip. Paul Chek Response: If the exercises does hundreds of crunches day in and day out, as many do, there is a potential for a functional shortening of the iliopsoas musculature. This is not because the muscle adaptively shortens as a muscle does when your arm is placed in a case. It is a case of the brain moving toward what I refer to in my seminars as "the position of strength." I regularly demonstrate this to my interns by showing them how many people with forward head posture and round shoulders have a poor strength grade when tested in traditional physical therapy style (see Muscles Testing and Function by Kendall and Kendall), yet if you lower their arm twenty degrees and retest, "surprise" they test 5/5 (normal). In this case the muscle has added sarcomers, changing the point on the length force curve that maximum strength is generated, thus changing the position of functional strength. When testing any muscle that is out of balance with its neutralizers, it will always move toward the position which loads the strongest of the muscles resisting the test load. Therefore, those crunch addicts out there may develop anterior pelvic tilt as an adaptive posture driven by the nervous system, in quest to find a "position of strength"! > > and (iii) are not very functional since abs and obliques are > > 'tonic' (his term) muscles. > > > (I took (iii) to mean they are stabilizers. I know we have discussed > > that most muscles can serve both moving and stabilizing functions. His > > point was that rarely do we use the abs and obliques for anything other > > than stabilizing--except when we are doing direct ab training.) > > I agree with your physio here. > > > He said that there will be a trend back to sit ups with straight legs. > > Anything's possible. I feel that exercises should be selected according to > what is best for the particular person rather than dictated by whatever the > current trend is. Paul Chek Response: Don't be so quick to agree here Chad. The abdominal musculature are classified by many books as "phasic", not tonic. In Scientific Back Training, I give clear classification criteria by which muscles are classified as either tonic or phasic. For those really interested that can't wait to get to one of my seminars or to view the video tapes, do a literature search for papers written by Vladimir Janda or Karel Lewit. Once you understand the classification criteria, it becomes very clear that the abdominal musculature are phasic, although they do carry-out many tonic duties; what else would you expect from a set of muscles with nine sources of innervation! (most muscles have one primary and one secondary source of innervation) > > He further claimed that the best ab training was simply tightening the > > pelvic floor muscles. > > I disagree here. I just tried it and felt no tension in my abs at all. How > could it be the best? > That is similar to saying that performing calf raises is the best way to > strengthen the hamstrings. Just not true. Paul Chek Response: He would have been far better off to say "the pelvic floor muscles can be trained by effective use and proper motor sequencing of the deep abdominal musculature". I will discuss this very important issue in Training Jane, Not Tarzan. Few in the fitness industry realize that 47% of women (mean age 38.5) are incontinent! If you really want to learn how to train the abdominal wall effectively, to improve work and sports performance, and to improve stability of the pelvic floor in females you must stop reading muscle magazines. For God sake, how many times will they print articles about crunches and hanging leg raises?! > > If he's right about abdominal training, then power lifters who disdain > > training for a six pack might have been on to something all along. > > While I disagree with much of what your physio said, I do think that the > power lifters are on to something here, especially if they do much of their > training without a belt. I would like to see an EMG study on this, but I > will speculate that the abdominal muscles contract just as hard if not > harder during heavy squats and dead lifts than for crunches or sit-ups. > Anyone have data on this? Be careful here! Very few power lifters have functional abdominals. There is a significant number of power lifters with low back pain, equally as many wearing weight belts (see my article titled "Back Strong and Beltless" on Caleb Bacon's web site). I can hardly begin to go into this here. It takes me eight hours to give my Scientific Abdominal Training lecture and I am pressed for time! If you want to see the difference between "functional" and "dysfunctional abdominals," look at the Winter 1997 edition of "Bigger Faster Stronger" magazine. To see functional abdominals, view Chris Gizzi doing a power clean on pg. 77, then turn to pg. 66 and look at the Budwiser tumor along for the ride on Reggie White's squat! > When you next see your physio, see if he can further explain some of his > statements, or respond to some of the points I brought up. I would be > interested in his further comments. > Chad Reilly CSCS Chad, I hope I have cleared some things up for you and the readers on the list. Paul Chek MSS, HHP, NMT Founder Corrective High-performance Exercise Kinesiology certification Paul Chek Seminars www.paulchekseminars.com 565 Pearl Street, Suite 108 La Jolla, CA 92037, USA Ph: (619) 551-8789 Fax: (619) 551-0587