[Gu, Dandong] Hengyang Normal Univ, Sch Phys Educ, Hengyang, Peoples R China.
[Gu, Chenling] Cent South Univ Forestry & Technol, Changsha, Peoples R China.
[Gao, Zan; Oginni, John] Univ Tennessee, Dept Kinesiol Recreat & Sports Studies, Knoxville, TN 37996 USA.
[Ryu, Suryeon] Univ Minnesota Twin Cities, Sch Kinesiol, Minneapolis, MN USA.
[Liu, Wenxi] Shanghai Jiao Tong Univ, Dept Phys Educ, Shanghai, Peoples R China.