World-Class Male Sprinters and High Hurdlers Have Similar Start and Initial Acceleration Techniques

Abstract

The effect of the inclusion of a high hurdle 13.72 m after the start line on elite sprint start and initial acceleration technique has yet to be investigated or understood. This highly novel study addresses that lack of information in an exceptional manner, through detailed biomechanical analysis of the world's best sprint and hurdle athletes, with data collected in situ at the 2018 IAAF World Indoor Championships, held in Birmingham, UK. High speed videos (150 Hz) were compared for eight sprinters and seven hurdlers for the start and initial acceleration phase of the finals of the men's 60 m and 60 m hurdles. Temporal and kinematic data were supplemented by vector coding analysis to investigate mechanisms by which these world-class athletes translate their centres of mass (CM) up to the fourth touchdown post-block exit. The sprinters and hurdlers coordinated their lower limb and trunk movement in a similar manner throughout the start and initial acceleration phases, which contributes new conceptual understanding of the mechanisms that underpin start and initial acceleration performance. Differences between groups were initiated from block set-up, with the hurdlers utilising a larger block spacing, but with the front block nearer to the start line than sprinters. Even after accounting for stature, the biggest differences in the raising of the CM occurred during the block phase, with hurdlers greater than sprinters (difference in vertical CM displacement scaled to stature = −0.037, very large effect size). Subsequent flight phases showed the biggest differences in the translation of the CM, in part due to longer flight times in the hurdlers, whilst the techniques of the two groups generally converged during the ground contact phases of initial acceleration. In highlighting that similar techniques are used by world-class sprinters and hurdlers, despite differing task constraints, this study has provided invaluable insights for scientists, coaches, and athletes, that will inform further developments in understanding and practice across both sprints and hurdles.

Biomechanics of World-Class Men and Women Hurdlers

“…The digitizing process was centered upon critical events (e.g., touchdown, take-off), and identified 17 key anatomical locations (head, shoulder, elbow, wrist, metacarpophalangeal, hip, knee, ankle, and metatarsophalangeal joint centers). The reliability of the digitizing process conducted has been documented previously (Bezodis et al, 2019). The Direct Linear Transformation (DLT) algorithm (Abdel-Aziz et al, 2015) was used to reconstruct the 3D coordinates of each anatomical location from individual camera's x-and y-image coordinates.…”

“…The distance between hurdles in the women's race is 8.50 m, with a 13.00 m approach run and a 10.50 m run-out to the finish; in the men's race the distance between hurdles is 9.14 m, with a 13.72 m approach run and a 14.02 m run-out (World Athletics, 2019). The closeness of the first hurdle to the start line results in a different start technique from that used by sprinters (Bezodis et al, 2019) and, although it is the fastest athlete over the total race distance who wins, the height and distance between the hurdles has a profound effect on the running speeds achieved, with hurdlers not reaching peak speeds until the run-out (Graubner and Nixdorf, 2011). This restriction on speed is not only apparent when crossing the hurdle itself but when recovering speed after clearing it, and in preparing for the next hurdle (McDonald and Dapena, 1991).…”

Evolution of the Hurdle-Unit Kinematic Parameters in the 60 m Indoor Hurdle Race

“…Interestingly, for both genders, a greater step width over the first hurdle was related to a better split time. This had not been previously measured in competition, even though other studies focused on the approach run phase [36][37][38] and provides clear information on how the best hurdlers perform at the beginning of the race and negotiate the short take-off distance to the first hurdle.…”

Kinematic Analysis Of Hurdles Clearance Techniques And The First Inter-Hurdle Stride Over 110-Metre Hurdles: Comparisons Between Specialists And Decathletes

“…Thus, athletes, coaches, and researchers have sought to improve hurdles performance by placing more emphasis on the kinematic analysis of hurdling techniques. Over the years, there has been a considerable amount of biomechanical literature concerning the kinematic analysis of hurdle clearance at different levels of performance in both male and female athletes [2,[4][5][6][7]. However, there has been little information comparing the various characteristics of movements of top-level hurdles specialists to those of high-level combined events athletes.…”