In skill acquisition for periodic body movements such as cascade juggling, establish-
ment of stable body movements seems crucial. However, we have a further question:
do all jugglers acquire such common skills through standard developmental processes?
Consequently, we mainly investigated development of three types of stabilities: the
stability of chest movement representing torso movement, the stability of wrist move-
ment representing arm swing, and the stability of time interval representing swinging
rhythm. In addition, we also investigated participants’verbal reports on their inten-
tional concerns for achieving optimum learning during practice. In the experiment,
novices practiced three-ball cascade juggling over a period of one week. The findings
revealed that two of the five intermediate level jugglers who performed over 100 suc-
cessive catches established individually unique body movements. Results also revealed
the possibility that such specific body movements related to their intentional focuses
during practice.
