From block clearance to sprint running: Characteristics underlying an effective transition

Abstract

The aim of this study was to characterize the specifics of the sprint technique during the transition from start block into sprint running in well-trained sprinters. Twenty-one sprinters (11 men and 10 women), equipped with 74 spherical reflective markers, executed an explosive start action. An opto-electronic motion analysis system consisting of 12 MX3 cameras (250 Hz; 325,000 pixels) and two Kistler force plates (1000 Hz) was used to collect the three-dimensional (3D) marker trajectories and ground reaction forces (Nexus, Vicon). The 3D kinematics, joint kinetics, and power were calculated (Opensim) and were time normalized to 100% from the first action after gunshot until the end of second stance after block clearance (Matlab). The results showed that during the first stance, power generation at the knee plays a significant role in obtaining an effective transition, representing 31% of power generation in the lower limb, in the absence of preceding power absorption. Furthermore, the sprinter actively searches a more forward leaning position to maximize horizontal velocity. Since success during sprinting from the second stance onwards involves high hip and ankle activation, the above-mentioned three characteristics are specific skills required to successfully conclude the transition from start block into sprint running.

On the Importance of “Front-Side Mechanics” in Athletics Sprinting

“…10,18 Mann & Murphy 20 expressed the two first variables in absolute horizontal distance, but we chose an angular expression to avoid the possible influence of varying dimensions among athletes. Overall, our results did not reveal an association between sprint performance and any of the analysed variables related to configuration at touchdown (Table 3).…”

“…8,[10][11][12][13][17][18][19] In contrast, authors of the International Association of Athletics Federations (IAAF) Coaches Education and Certification System's sprint curriculum argue that the elite world of sprinting for more than 20 years has optimized front-side mechanics and minimized back-side mechanics. 20 According to Mann & Murphy,20 groups of variables related to these concepts can be identified during any portion of the sprint race by simply drawing a straight line through the upper body (trunk).…”

Control of propulsion and body lift during the first two stances of sprint running: a simulation study

“…The sprinter aims to generate maximal forward acceleration during the transition from start block into sprint running (Bezodis, Salo, & Trewartha, 2010;Golden, Pavol, & Hoffman, 2009). Simultaneously, the athlete needs to generate sufficient upward acceleration to erect from a flexed position in the start blocks to a more extended position (Debaere, Delecluse, Aerenhouts, Hagman, & Jonkers, 2013). Specific technical skills are therefore needed to successfully achieve this transition.…”

Kinematic analysis of the block start and 20-metre acceleration phase in two highly-trained sprinters: A case report

“…Aerenhouts et al [24] also support the view that an appropriate technique applied in this phase determines the performance. Furthermore, according to Debaere et al [12], during the transition phase, the sprinter actively prepares for a more forward leaning position, which corresponds with the above mentioned values in specific joints.…”

“…Admittedly, similar research has been done up to date, but with the use of the popular video-motion analysis method rather than using inertial sensors. For instance, such studies were carried out by Bezodis et al [11], Debaere et al [12,13], or Slawinski [14,15]. Moreover, in contrast to other studies, we collected data during a real training session in the tapering phase of the competition period and obtained an actual picture of the block start technique which is not a standard way of testing athletes.…”