The Biomechanics of the Track and Field Sprint Start: A Narrative Review

Abstract

The start from blocks is a fundamental component of all track and field sprint events (≤ 400 m). This narrative review focusses on biomechanical aspects of the block phase and the subsequent first flight and stance phases. We discuss specific features of technique and how they may be important for a high level of performance during the start. The need to appropriately quantify performance is discussed first; external power has recently become more frequently adopted because it provides a single measure that appropriately accounts for the requirement to increase horizontal velocity as much as possible in as little time as possible. In the "set" position, a relatively wide range of body configurations are adopted by sprinters irrespective of their ability level, and between-sprinter differences in these general positions do not appear to be directly associated with block phase performance. Greater average force production during the push against the blocks, especially from the rear leg and particularly the hip, appears to be important for performance. Immediately after exiting the blocks, shorter first flight durations and longer first stance durations (allowing more time to generate propulsive force) are found in sprinters of a higher performance level. During the first stance phase, the ankle and knee both appear to play an important role in energy generation, and higher levels of performance may be associated with a stiffer ankle joint and the ability to extend the knee throughout stance. However, the role of the sprinter's body configuration at touchdown remains unclear, and the roles of strength and anatomy in these associations between technique and performance also remain largely unexplored. Other aspects such as the sex, age and performance level of the studied sprinters, as well as issues with measurement and comparisons with athletes with amputations, are also briefly considered.

Three-dimensional kinetic function of the lumbo-pelvic-hip complex during block start

“…The instant of each toe-off was defined as less than 10 N of the vertical reaction force on each foot. The block phase was then divided into two (double-stance and single-stance) phases by the instant of the toe-off of the rear leg [2].…”

“…In sprinting (60-400 m) races, sprinters have to start from the crouching position with starting blocks [1,2]. The starting performance accounted for 42% of the variance within the 100 m personal best (PB) in 154 male and female sprinters ranging 9.58-14.00 s [3].…”

Gender-Related Differences in Mechanics of the Sprint Start and Sprint Acceleration of Top National-Level Sprinters

“…The ability to quickly accelerate from a static position and maintain high running velocities are clear determinants of performance in sprint race events and also key performance indicators in many other sport disciplines [ 1 , 2 ]. Although numerous studies have been published addressing neurological, physiological and biomechanical determinants of sprinting [ 3 , 4 , 5 , 6 ], due to its complexity and myriad of factors affecting sprinting performance, the sprint start continues to attract scientific attention.…”

“…Due to the apparently strong influence on total running time, particularly in short distance events (i.e., 60 and 100 m), sprinting block phase performance has been extensively investigated for decades [ 1 , 7 , 8 , 9 ]. Since a number of kinematic and kinetic variables have been used to evaluate sprinting block phase performance, the conclusions of those studies were frequently affected by the variable considered (see Bezodis for details; [ 1 ]).…”

“…Due to the apparently strong influence on total running time, particularly in short distance events (i.e., 60 and 100 m), sprinting block phase performance has been extensively investigated for decades [ 1 , 7 , 8 , 9 ]. Since a number of kinematic and kinetic variables have been used to evaluate sprinting block phase performance, the conclusions of those studies were frequently affected by the variable considered (see Bezodis for details; [ 1 ]). Another problem with the sprinting literature is that the block start performance has been generally evaluated through non-standardized custom build laboratory settings [ 8 , 10 , 11 , 12 , 13 ], not allowing the direct comparison of mechanical variables among different studies.…”