-----Original Message-----
From: Ivan Hooper [SMTP:[log in to unmask]]
Sent: ? ??? 01 2000 18:54
To: Physio List
Subject: Re: Ab Exercise Myths
In response to Mel's email, I agree that conscious activation of transverse abdominus in complex daily activities is not going to achieve what alot of people think it will. The initial work of Hodges, Richardson and Jull demonstrated a delay in the onset timing of TA whilst performing both upper limb and lower limb tasks in those subjects with chronic low back pain. His work (and that of Hides) suggests that TA and multifidus have a role to activate immediately prior to limb movements to enhance segmental stiffness and thereby protect the spine from the displacing forces generated by the limb movement.
Jull et al (1998) report on two cases where isolated activation training of TA and multifidus has changed the involuntary activation timing of these muscles during limb activities (ie decreased the delay in onset), and also changed the VAS pain scores of the two subjects. But having had numerous discussions with Jull and Richardson about this very topic, they don't believe that we should be getting patients / athletes to consciously activate TA and Multifidus during activity. Obviously to have any effect on what are subconscious motor engrams, thousands of repetitions of the correct pattern need to be performed. Our aim is to make the correct pattern of activation the dominant pattern. To achieve this we as therapists need to ensure that an exercises that are performed are done correctly. Exercises done incorrectly simply reinforce the wrong movement pattern. That is why we are now tending to do alot of these isolation exercises with the aid of the ultrasound feedback.
Generally, asking a patient / athlete to activate TA and multifidus during normal or sporting activities causes overactivity of the rectus abdominus and obliques, thus generating a "global activation" of the whole abdominal muscle group. Precisely the pattern we are trying to break down. Certainly with athletes, who all tend to do things at 100%, they try "too hard". Instead of activating TA at 20 - 30% MVC to enhance it's tonic stability role, they activate at much higher percentages of MVC. Jull and Richardson believe that the patient / athlete needs to perform enough repetitions of the activation of these muscles in isolation so that eventually there may be some small flow over to normal activities.
The therapeutic exercises used to rehabilitate the function TA and multifidus take a great deal of conscious thought and thorough self and therapist directed error checking and feedback. Even though the correct activation of these muscles in all activity is what we ultimately want, training them this way doesn't necessarily work. Until the very late stages of rehabilitation, I believe it is near impossible to get patients to perform the correct activation of these muscles in functional / sporting movement patterns.
I hope this input is of use.
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Ivan Hooper
Sports Physiotherapist
Optima Physiotherapy & Massage Therapy
Cnr Ashgrove Ave & Enoggera Rd
Newmarket Q 4051
(W) 07 3356 3312 (F) 07 3356 0234
(H) 07 3371 7881 (M) 0413 946 308
EMail : [log in to unmask]
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[אורי]
dear Ivan
c
an u send me more details about ] the [אורי] ultrasound biofeedback
thank u in advance
uri yaros
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