That tension is transmitted to the teeth which can create several hundred
and maybe even thousands of pounds of pressure per square
inch...especially if area of touch of one lower tooth and upper tooth is
small.
The problem is that tension, one can restrict blood flow. Another problem
is that often one doesn't even know they are clenching their jaws that
hard.
Suggestions:
1. Relax the lower jaw and lightly place the tongue on the roof of the
mouth if nose breathing.
2. When you open your mouth don't think of your lower jaw like this "<"
rather think of it as a "=". By that I mean when you open you jaw,
stretch the back of the jaw down...like one of the egg eating snakes. It
will allow you to relax the jaw muscles.
3. In the marathon when the Super Four Support Team is working along the
course, the most common verbal suggestion we give to runners is: "Relax
your jaw." That jaw tension effects the neck muscles and gradually works
its way down the arms and upper body...and any unnecessary tight muscle is
draining calories away from where they are needed to finish well.
4. In track work outs, the idea that the lower jaw goes along for the
ride. When you see world class sprinters running, you'll see a relaxed
lower jaw and with some runners you can see it's slight movement up and
down as the foot plants.
--
In health and on the run,
Ozzie Gontang
Maintainer-rec.running FAQ
Director, San Diego Marathon Clinic, est. 1975