whe

Film analysis included: 1) securing distances traversed by the ball
in recorded time; 2) obtaining sorta description of the throws; 3) tracing
body positions, Three measures of objectivity of trial verbal descriptions
were secured: 1) a percentage of agreement between the main descriptive
items of five matched descriptions - 94,1%5 2) a percentage of agreement
between all items --71.4%; 3) a coefficient of correlation between the
matched time readings of five throws -4+, 98%, 004. The result under (2) dictated
minute detail in the final descriptions.
C. Results and Conclusions
Treatment of the data has yielded among others the following results and
conclusions:
1. Initial velocities of the hard overhand dent one from eight feet per
second average for a two-year-old girl to seventy-five feet per second average
for a twelve-year-old boy.
2, Movement and timing features of the throw demonstrate an age series of patterns,
3. Six typical age patterns of movement for the whole throw were demonstrated.
These six types, of which only four are clearly defined, can be assigned to
an age schedule and show a developmental sequence as follows: (incompletely
though briefly stated) ;
Stage I. Typical antero-posterior movements of body and throwing arm over
feet which remain in place. (Type II) Type I is the incipient stage,
showing scarcely any body movement as yet. Age 2 to 3, overlapping into
3 to 4.
Stage II, Introduction of arm and body movements in the horizontal plane
over feet which remain in place. (Type III) Ages 35 to 5 years.
Stage III. Introduction of stepping with the unilateral foot {right
‘foot in right-handed throwing); combination of antero-posterior and hori-

zontal features. (Type IV) Ages 5 to 6.