Physical and mechanical properties of various field lacrosse balls.

Although the sport of lacrosse has evolved dramatically over the last few decades and is presently the fastest growing team sport in the United States, the current specifications for balls date back to 1943. The purpose of this study was to see if various commercially available field lacrosse balls meet these specifications and to determine additional mechanical properties of the ball that may more completely characterize ball performance. Eight models from several manufacturers were tested. Seven models were designated for game play, while one model was promoted as a practice ball. In accordance with the specifications, the mass, circumference, and rebound height were recorded for one dozen balls from each model. The load required to compress the balls 0.0125 m and the coefficient of restitution (COR) with an incident speed of 26.80 m/s were also determined. We found that some balls met several of the specifications, but none of the models had every ball meet all the specifications. For the two measures of ball liveliness, rebound height had a weak correlation with COR. Ball compression loads averaged about 750 N over most models, but were almost 85% less for the practice model. It appears that current governing body specifications are outdated, as no ball model we tested met these specifications. The determination of ball liveliness at more realistic speeds should also be taken into account. Since balls with low compression loads can pass through face protectors worn by lacrosse players, the sport's governing bodies may wish to consider a specification on ball compression.