I have looked at a few females under 3D high-speed videography and
compared them to a large database of collegiate pitchers (male) in
overhand throwing of a fastball. The differences I saw seemed to be
related to lack of technique due to lack of experience throwing overhand
and not so much with the sex of the person throwing the ball. In
addition, total body lack of strength and poor timing of body segments
in the throwing progression contributed to the effect of "throwing like
a girl". To be more specific, I found that females (or inexperienced
throwers) not acustomed to throwing overhand tend to keep the elbow
about about 40-60 degrees more flexed approaching release of the ball.
This increased flexion near release gives an observer the impression
that the inexperienced thrower is almost pushing the ball ("throwing
like a girl"). This may be partly due to the insecurity of wanting to
allow the elbow to approach max extension while moving at top speed near
ball release as college male pitchers do (155-165 deg at release). The
inexperienced thrower will tend to keep the ball and hand closer to the
ear approaching release hence the elbow flexion. This increased flexion
state severely decreases the body's ability to apply force to the ball
therefore, ball velocity is dramatically reduced. Other gross
differences between an experienced and inexperienced thrower are in the
amount of shoulder external rotation during the cocking phase and the
internal rotation velocity approching ball release. Timing issues
involving first-stride leg placement, second-pelvic rotation,
third-torso rotation, fourth-shoulder ext rotation, fifth-elb extension,
and sixth-shoulder int rotation (in that order) are all screwed up in
the inexperienced thrower.

My opinion is that differences in throwing techniques between males and
females are more related to lack of experience (as measured in # of
balls thrown during childhood, teen years, adult hood) rather than to
differences in anatomy and/or skeletal mechanics associated with
different genders.

Patrick Castagno
__________________________________________________ __
Patrick W. Castagno, MS
Manager/Biomechanist - duPont Hospital for Children
Gait Analysis Laboratory
1600 Rockland Road
Wilmington, DE 19899

"The Victory lies in the struggle."

Brad Wright wrote:

It's widely held (among boys, at least) that girls throw balls (and
punches) different from boys, hence the familiar phase, "throw like a
girl". Does anyone know (a) whether any significant sex differences
throwing style have been demonstrated in the biomechanics literature
(b) what biomechanical differences might account for throwing style
differences, if they exist?

Anecdotally, my impression is that very small children show no
throwing style differences between the sexes; only later do any
differences become evident, and they may be due largely to differences
experience or training. However, I've heard it argued that even
athletically inclined women tend to throw more "like a girl" than the
typical man. Any ideas (or better yet, data)?


Brad Wright
University of Chicago

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