具运动伤害潜在关系的球体物理特性——长柄曲棍球与棒球之比较

Physical characteristics related to potential sports injuries:Comparison of lacrosse ball and baseball

目的研究长柄曲棍球与棒球球体的物理特性,探讨长柄曲棍球球体造成伤害的潜在风险。方法实验球体为长柄曲棍球与棒球各12颗,检测前皆通过24 h环境控制,使球体温湿度一致,再进行长柄曲棍球与棒球球体质量、圆周、压缩值与恢复系数等物理特性的测量,以独立样本t检验比较长柄曲棍球与棒球的差异。结果长柄曲棍球球体质量为(144.65±0.29)g,圆周为(19.97±0.02)cm,压缩值为(91.76±1.23)kg,恢复系数为(0.633±0.011);棒球球体重量为(146.12±0.45)g,圆周为(23.20±0.06)cm,压缩值为(124.76±1.68)kg,恢复系数为(0.528±0.005)。长柄曲棍球的质量、圆周与压缩值均显著小于棒球,恢复系数则显著大于棒球(P<0.05)。结论长柄曲棍球的物理特性虽符合国际标准规范,但长柄曲棍球与棒球一样都有造成严重运动伤害的风险。建议可依据年龄与技巧进行球体分级,给予不同等级的选手使用,以降低运动受伤风险。

Objective To study the differences in physical characteristics of lacrosse balls and baseballs, so as to investigate the potential sports injuries caused by lacrosse balls. Methods Twelve lacrosse balls and 12 base- balls were used as testing samples. All testing balls were under conditioning control for 24 h to make sure temper- ature and humidity were consistent before measurement. The physical characteristics such as ball weight, circ- umference, compression-displacement and restitution coefficient were measured, respectively. Independent- sample t-test was used to compare the differences in lacrosse balls and baseballs. Results The lacrosse ball weighted （ 144.65 ± 0.29） g, and its circumference, compression-displacement, and restittition coefficient were （ 19.97 ±0. 02） cm, （91.76 ±1.23 ） kg and （0.633 ± 0.011 ）, respectively. The baseball weighted （ 146.12 ± 0.45） g, and its circumference, compression-displacement and restitution coefficient were （23.20 ± 0.06） cm, （124.76 ± 1.68） kg, and （0. 528 ± 0.005）, respectively. The lacrosse balls are significantly smaller in weight, circumference and compression-displacement than the baseballs （ P 〈 0.05）. The restitution coefficient was sig-nificantly greater than baseballs （ P 〈 0. 05）. Conclusions The physical characteristics of lacrosse balls are in compliance with international standard. However, lacrosse balls have the same risk of causing serious injuries as baseballs. To reduce the risk of sports injuries, it is recommended that the specification of lacrosse balls need to be classified for different age and skill levels.