House Condition Pocket % (House)
Standard Deviation (Pocket)
Standard Deviation (All) Total Area (Boards)
things about the bowlers we’re looking at. It’s like math. Numbers are the same in Europe, Japan and America. It can be the same with bowling. We can talk about a certain hand position, certain footwork, certain arm swings, everything. When we can do that, we can really start to analyze things.” That analysis will pay
dividends for the whole sport. Once coaches get on the same page, they will teach in a more precise way, and bowlers everywhere will start to con- sider new and more accurate ways to improve their games. Three years ago, USBC
researchers conducted a study to see if there were advantages to using different bowling styles on both house patterns and Sport Bowling patterns. Researchers used the three
traditional styles — cranker, stroker and tweener — in their test. But to do so, they had to define the styles to an extent. Those definitions were limited to the actions of the ball after they left the bowlers’ hands. Effectively, they defined the differences between cranker, stroker and tweener by ball speed, rev rate and axis angle: Stroker: 220 r.p.m. Axis angle of 80 degrees, 19 m.p.h. Tweener: 325 r.p.m. Axis angle of 70 degrees, 18 m.p.h.
Cranker: 520 r.p.m. Axis angle of 60 degrees, 19 m.p.h. Each bowler was tested
separately on a fresh house and Sport condition. Bowlers were allowed to practice on a similar condition on an adjacent lane, but all testing was done on the same surface. The idea was to allow the
26 USBOWLER WINTER 2010-11
Stroker 85% 1.19
1.16 4.06
bowlers to gain a clue of where they had the best line to the pocket. After an accept- able amount of shots, C.A.T.S. (Computer Aided Tracking System) data was evaluated for each style. During the test, they looked at four cat-
Tweener 80% 1.00
1.57 3.78
Cranker 80% 1.29
1.17 4.14
egories of data. Pocket percentage, which is the percentage of balls hitting the pocket (not necessarily a strike.) Standard devia- tion (Pocket) includes only those shots that hit the pocket and was used to determine how much variation there was in those shots. Standard deviation (All) is the variation of every shot thrown. Those standard deviation numbers were cal- culated at the sensor closest to the end of the oil patterns (37 feet). Total Area is the area the bowler had at the end of the pattern and was still able to hit the pocket. (See charts above.) The data was interesting
in the sense that it verified the general difficulty of a Sport shot versus a standard house shot. It wasn’t surprising that all bowlers had an average of three more boards of total area when changing from Sport to house Conditions. Additionally, the standard deviation (Pocket), for all styles, basically doubled when they went to the house shot. That boost led to an average 30 percent pocket percentage increase. But when it came to deter-
mining anything about the differences between bowling styles, the tests were fairly inconclusive. Strokers led the way in Total Area on the Sport shot and crankers led the way in Total Area on the house shot. Tweeners lagged behind in area on both conditions, but the pocket percentage was
POWER MAN: Team USA member and PBA star Tommy Jones is often thought of as a cranker because of his ball speed, big hook and high revs.
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