Watching the Monkeys

Gorillas never bend their arms past halfway under load. Nor do the other apes.
Same goes for monkeys. By "under load" I mean during the act of climbing, swinging
or launching themselves from one branch to the next. That fact got me thinking,
because afer thirty years of teaching elementary phys. ed. I can recall scores of
times when students complained of pains in the elbows when tested on pull-ups and/or
chin-ups. Not sore muscles but PAIN IN THE ELBOW JOINT, especially the girls, who
were for so many years subjected to the FLEXED ARM HANG as their method of testing
upper body strength (the finished or top position of a pull-up, where they keep their chin
over the bar for time).

WHY IS THIS?

Because ALL MUSCLE CONTRACTION, whether pushing or pulling, results in
compression of the joints involved. Or should. We don't want our joints
all loosey-goosey when our muscles are exering force.

SOMETHING WILL SHEAR, SOMETHING WILL ABRADE. And because a
FULL CHIN-UP is an UNNATURAL MOTION, where the arm flexors cut out at
the halfway mark and can no longer hold that elbow joint tightly together,
they eventually give one SORE and ABUSED elbows.

You'll never see a GORILLA or a CHIMP doing chin-ups -- although I did see
a 475 pound SILVRBACK jump ten feet out into space and CATCH HIMSELF
WITH ONE HALWAY BENT ARM on a bar that was around seven feet high. It was
effortess, and he remained that way, with his single supporting arm bent
at 90 degrees, for severl seconds before swinging to another bar five feet
away and of a smilar height. IMAGINE THE FORCES INVOLVED . . !