Investigating the influence of Taekwondo body protectors size on shock absorption

Article type: Research Article

Authors: Jeong, Hee Seong^{a; b} | Lee, Sae Yong^{a; b; c} | Noh, Hyung Jun^d | O’Sullivan, David Michael^{e; 1; *} | Lee, Young Rim^{f; 1; *}

Affiliations: [a] Department of Physical Education, Yonsei University, Seoul, Korea | [b] International Olympic Committee Research Centre Korea, Seoul, Korea | [c] Institute of Convergence Science, Yonsei University, Seoul, Korea | [d] Department of Taekwondo, Nazarene University, Cheonan, Korea | [e] Department of Sports Science, Pusan National University, Busan, Korea | [f] Institure of Haeram Education, Gangneung-Wonju National University, Gangneung, Korea

Correspondence: [*] Corresponding authors: David Michael O’Sullivan, Department of Sports Science, Pusan National University, 2, Busandaehak-ro 63beon-gil, Geumjeong-gu, Busan, 46241, Korea. Tel.: +82 51 510 2818; Fax: +82 51 510 3745; E-mail: davidosullivan@pusan.ac.kr. Young Rim Lee, Institute of Haeram Education, Gangneung-Wonju National University, 150, Namwon-ro, Heungeop-myeon, Wonju-si, Gangwon-do, 26403, Korea. Tel.: +82 2 2232 2073; Fax: +82 2 2123 8375; E-mail: wellcom0210@hanmail.net.

Note: [1] David Michael O’Sullivan and Young Rim Lee contributed equally to this work.

Abstract: OBJECTIVE: This study aims to compare and analyze the difference of impact force attenuation according to size and impact location on a Taekwondo body protector. METHODS: Body protectors sized 1 to 5, were impact tested by equipment based on the specifications in the European standard manual (EN 13277-1, 3). The impactor release heights were set to match impact energies of 3 and 15 J. The impactor was made from a 2.5 kg cylindrically cut piece of aluminum. Each body protector was impacted 10 times at the two impact energies and two locations. The differences in performance for each body protector size were compared using a two-way analysis of variance with a significance level of p< 005. The effect sizes were investigated using a partial eta squared value (η2). RESULTS: The significant mean differences between the body protector size and impact area (p< 005) and the average impact time of impact strengths 3 and 15 J were 0.0017 and 0.0012 s, respectively In addition, when an impact strength of 15 J was applied, the maximum resulting impact force exceeded 2000 N for both locations on all sizes. Furthermore, at an impact strength of 3 J size 3 significantly reduced the impact force more than the other sizes; however, size 1 showed the greatest shock absorption at an impact of 15 J. CONCLUSION: The results of this study show that the shock absorption of body protectors does not increase according to size; i.e., a larger body protector does not reduce the impact load more effectively. To improve safety performance, we recommend a maximum impact force of 2000 N or less for all body protectors.

Keywords: Taekwondo equipment, impact testing, injury prevention, shock absorption

DOI: 10.3233/THC-202598

Journal: Technology and Health Care, vol. 29, no. 4, pp. 667-675, 2021