Dear Mell,
You asked: "Let's see how long it takes now for fitness professionals to
start modifying their workouts and seminars to take account of this sort of
information.".
Well, judging from the arguments displayed on the "infomercials" as to why
people should buy a specific machine or device, by which half the world is
"educated" continuously, I wonder whether we'll live to see the day.
And what may be more important: I did an experiment a few years ago with a
group of patients (n=10) with (semi-)herniated discs, to see whether they
could stand ab-exercises. (I worked in a pratice where we would get a lot of
those patients from the area, because we had the best equipment.) Most gave
up after already a couple of repetitions, because of increasing pain. So, as
far as I'm concerned, the claim that working the abs. will improve back pain
(in general), should be forbidden. By law.
:-),
Frank
----- Original Message -----
From: <[log in to unmask]>
To: <[log in to unmask]>
Sent: vrijdag 11 mei 2001 22:44
Subject: Bent Knee Situp Myths
Those of you have attended any of my Strength Camps or conference
presentations during the past 15 years will have noted that I always point
out that the PNF textbook (by Knott and Voss) refers to trunk movements with
knees and hips extended and not flexed, which apparently contradicts the
fitness myth of doing all ab exercises with hips and knees flexed. No matter
how often I stress that the hip and trunk flexors are meant to work in
collaboration and that isolation of the abdominal muscles is unnecessary,
and
quite futile in minimising back injury during situps, few people seem to
believe this (see my "Facts and Fallacies of Fitness" book for more
information on this topic).
My own EMG research has shown that several other activities offer greater
abdominal activation than crunches, conventional situps and physio ball
crunches, such as these which I teach at our Supertraining Strength Camps:
* Supine crunches (Roman chair style) with all of the body above the thighs
off the bench
* Drop backs (rapid eccentric stopping of a fall back over a pad such as an
AbMat)
* Rapid crunches with concurrent action of pelvis and upper body
* Pike or semi-pike jumps (with or without added loading)
* Rollouts with Olympic bar against elastic band resistance
* Ballistic Olympic presses
* Heavy standing or kneeling cable crunches
* Explosive crunches with added loading
* PNF trunk patterns against manual resistance (supine)
Consequently, it was a great pleasure to come across this following
research:
---------------------------
Andersson, E.A., Nilsson, J., Ma, Zhijia, M., & Thorstensson, A. (1997).
Abdominal and hip flexor muscle activation during various training
exercises.
European Journal of Applied Physiology, 75, 115-123
Bending the hips and knees during abdominal exercises (such as crunches) is
supposed to reduce the amount of work performed by your hip flexors, leading
to greater isolation of the abdominal muscles. However, researchers found
that moving the legs from straight to bent during the trunk curl actually
increased hip flexor activity by 111%.
"There is a misconception that the involvement of the hip flexors will
decrease by flexing the legs in sit-ups", says primary author, Dr Eva
Andersson. "We found the opposite pattern, i.e. the hip flexor muscles were
always engaged to a higher degree with bent than with straight legs"
<www.thefactsaboutfitness.com/research/abdominals.htm>
This same research project found that:
1. Lying leg raises work the abdominals 29% harder than trunk curls
2. The exercise working the abdominals the hardest is the sit-up with
straight, unsupported legs
3. Trunk curls produce the lowest hip flexor activity
4. Hip flexors work the hardest during the lying leg raise
5. Single leg raises are the least effective abdominal exercise
--------------------
Let's see how long it takes now for fitness professionals to start modifying
their workouts and seminars to take account of this sort of information.
Dr Mel C Siff
Denver, USA
http://groups.yahoo.com/group/Supertraining/
|