       (JPES), 19(1), Art 95, pp. 658  668, 2019 online ISSN: 2247  806X; pISSN: 2247 – 8051; ISSN  L = 2247  8051 © JPES 658  Corresponding Author: SAMIHA AMARA, Email: samiha_ath@yahoo.fr            SAMIHA AMARA 1 , BESSEM MKAOUER 2 , HELMI CHAABENE 3 , YASSINE NEGRA 4 , FATMA Z. BEN SALAH 5 1,2 Higher Institute of Sport and Physical Education of Ksar Said, Manouba University, Manouba, TUNISIA; 3 Division of Training and Movement Sciences, Research Focus Cognition Sciences, University of Potsdam, Potsdam, GERMANY; 3,4 Higher Institute of Sport and Physical Education of Kef, Jandouba University, Kef, TUNISIA; 4 Research Unit, Higher Institute of Sports and Physical Education, Ksar Said, Manouba, TUNISIA; 5 Faculty of Medicine of Tunis, University of Tunis Elmanar, TUNISIA. Published online:March 31, 2019 (Accepted for publication February 28, 2019) !"#$"%%! &: This study aimed at exploring the key kinetic and kinematic factors of 110m hurdle clearance performance using threedimensional (3D) analysis system. Ten national level athletes participated in this study. The kinematic analysis of the hurdling sequences was recorded using ten mutually synchronized digital cameras. Body markers were digitized using SkillSpector ® software. Groundreaction force was calculated by using rigid body inverse dynamics using the Smith’s equations. All variables were combined into components through a principal component analysis. The retained components have been used in a multiple regression analysis. Twenty variables were retained as key hurdling performance determinants. Specifically, the horizontal and vertical velocity of the centre of mass (COM) and the leadleg/trailleg in all phases (i.e., takeoff, flight, and landing), horizontal and vertical displacement of the COM, the leadleg/trailleg vertical displacement, and the flighttime at clearance are among the main hurdling performance determinants. Overall, to improve hurdling performance, greater horizontal velocity, lower vertical displacement at flight and lower contacttime at the take off phases through a higher rate of force development are needed.  ’ Motion analysis; inverse dynamic; hurdling; track and field  Hurdling is a complex technical event that requires high levels of physical fitness (Iskra, 1995). In fact, sprint speed, intersegmental coordination, reactive strength, and great technical skills are the most key physical fitness aspects that should regularly be developed and routinely implemented in training programs to succeed the race (Coh, 2003; Coh & Zvan, 2018). In particular, the technique of clearing the hurdle represents one of the most determinant elements defining the competitive result (López, Padullés, & Olsson, 2011; McLean, 1994; Sidhu & Singh, 2015). In this context, Iskra (1995) indicated that the improvement of the 110m hurdle race technique represents one the central component of training. Kinetic and kinematic analysis of 110m hurdle clearance, in particular, may help understanding the critical factors that influence performance and assist coaches exploring the theoretical basis for hurdle running training (Salo, Grimshaw, & Viitasalo, 1999). Additionally, the kinetic and kinematic outcomes are widely used to help improving athletes’ training and performance, alike (Coh, Jost, & Skof, 2000; Salo et al., 1999). Previous studies examined the kinematic analysis of Colin Jackson’s clearance (World Record Holder) at the fourth hurdle in the 110m race (Coh,2003; Coh, Zvan, and Jost,2004; Coh and Zvan, 2018). Authors agreed that the horizontal velocity of the centre of mass (COM) at takeoff and during clearance, the height of COM above the hurdle, the leadleg’s knee swing velocity, the flighttime, and the contacttime at the landing phase represent the key hurdling performance factors. In terms of kinetic factors, it has been demonstrated that the peak horizontal force at landing is paramount for an efficient hurdling (Coh and Iskra, 2012). It is noteworthy that all previous biomechanical analyses of hurdling were carried out on only one to three hurdles (Iskra & Coh, 2006) with a large variation in the hurdles selected for analysis. For instance, previous research focused on only the first (Lee, 2004; Lee, Park, Ryu, & Kim, 2008; Salo, 2002; Xu, Wang, & Yan, 2005), the second (Iliew & Primakov, 1978; Mclean, 1994), the third (Lee, 2009; Salo, Peltola, & Viitasalo, 1993; Tsarouchas, Papadopoulos, Kalamaras, & Giavroglu, 1993), the fourth (Coh, 2003; Cooh et al., 2000; Li, Zhou, Li, & Wang, 2011; Ryu & Chang, 2011), the fifth (Coh & Zvan, 2018; Sidhu, 2016; Sidhu & Singh, 2015), the sixth (Li & Fu, 2000; Peak et al., 2011), the seventh (Shibayama, Fujii, Takenaka, Tanigawa, & Ae, 2011) the ninth (Iwkin, Jegorow, & Zukow, 1987; Salo & Scarborough, 2006), and the tenth hurdle (Lopez et al., 2011; Chow, 1998).