Castilho wrote:I read some amount of material about your studies over flexibility, and i really agree with almost everything you wrote, very logical insights. I did´t have the chance to bought one of your books yeat, but i´ll definitelly try to do that this month (i hope... short of cash, poor country...)
Your focus in the neural part of flexibility training really sounds logical to me. But here in Brazil, in the books published here, the amout of participation of the connective tissues and adaptations in these structures are claimed to represent a big role in the development of flexibility. A lot of authors here put emphasys in this point.
I found this article: http://www.scielo.br/pdf/rbme/v10n6/en_a02v10n6.pdf .
It´s wrote by some relevant researchers in physiology at (or is... i never know) Brazil. One of them was my professor in the graduation. I really want to hear your opinion about this article, specially about these points:
"The duration time seems to provide important physiological changes such as the remodeling of elastin and collagen molecules. These changes may be associated with alterations on the muscle-tendon units and fascia, caused by the increase on the tissueselasticity through hysteresis."
"The neural effects initially provide an increase on the range of motion before the actuation of the reflex system with the later participation of the spindles and the autogenic and reciprocal inhibitory actions caused isometric contractions that occurred during the length increase process and tension generation during stretching. However, these effects, initially important, seem not to produce significant results when compared with the hypothesis of reduction of the mechanical strengths. This reduction seems to occur due to changes on the viscoelastic properties of the soft and conjunctive tissues under constant stress during flexibility training."
I have read the article by
Viveiros and others and it shows that:
a) with static passive stretching (relaxed stretching) gains in the range of motion in the shoulder joint disappeared after 24 hours;
b) the greater range of motion was achieved during stretching, the more was lost during subsequent 24 hours rest (see point a);
c) in the short-term three sets of stretches were more effective than one, for example, 3 x 10 sec were more effective than 1 x 60 sec, 3 x 60 sec were more effective than 1 x 120 sec.
Practical conclusions a rationally thinking instructor might draw from this article could be that either one has to do these relaxed stretches more often than 24 hours apart or that it would be better to use more effective stretches than those relaxed used in this research, and that three sets of shorter stretches are generally more effective than one longer stretch.
Authors' conclusion, that increases in the range of motion are due more likely to changes in the fibrous connective tissue and its weakening, may apply to relaxed stretches of shoulder flexors but not necessarily to other kinds of stretches and other muscle groups. Do you think that weakened muscles can support two people (me and the woman) in a side split between chairs? For the likely explanation see articles by Fridén and others, and by Saxton and Donnelly, which I quote in
Stretching Scientifically.
I wrote on the issue of active muscle tension (neural factor) versus passive tension (mainly the connective tissue factor) in stretching on pages 112-114 and 120-124 in
Stretching Scientifically.
Here I quote my conclusion from page 114:
“For practical purposes, as long as you feel your muscles contract in response to a stretch, it means that relaxing the muscles can improve your stretch and that you should concern yourself more with nervous regulation of your muscles' tension and less with your muscles' connective tissue.”
Now, a general conclusion on sundry experts, authorities, researchers, etc.
While I was plodding through this poorly translated article (
Viveiros et al. 2004]), with its misinterpretation of at least one article they quoted (Bandy et al. 1997), the lack of explanation of peculiarities of the shoulder joint versus, say, knee or hip joints, and the lack of clear conclusions for practice, the thought struck me: Why do I bother? Can these researchers do what I can do? Can they do what my customers can do? And then I recalled that I had already written something that applies to this situation.
Here is what I have written in the subchapter “Other Stretching Methods” in the chapter “Questions and Answers on Stretching” of
Stretching Scientifically:
“For me to pay attention to any expert's claims, I need to see results that are better than those achieved by people who use my book,
Stretching Scientifically, or my video,
Secrets of Stretching. To see what I mean, look at some of the people who have used my method and took the trouble of photographing themselves and mailing me their photos, which are on our web site at
http://www.stadion.com/testimonial.html .”
If an explanation doesn't agree with facts it is the explanation that is wrong.