학술논문

KINEMATICS OF USAIN BOLT'S MAXIMAL SPRINT VELOCITY.
Document Type
Article
Source
Kinesiology. Dec2018, Vol. 50 Issue 2, p172-180. 9p.
Subject
*SPRINTING
*KINEMATICS
*RUNNING speed
*HIGH-speed video recording
*BIOMECHANICS
Language
ISSN
1331-1441
Abstract
This study investigated the maximal sprint velocity kinematics of the fastest 100 m sprinter Usain Bolt. Two high-speed video cameras recorded kinematics from 60- to 90-m marks during the men 100 m final at the IAAF World Challenge Zagreb 2011, Croatia. Despite a relatively slow reaction time (194 ms), Bolt won in 9.85 s (mean velocity: 10.15 m/s). His fastest 20-m section velocity was 12.14 m/s, reached between 70- and 90-m marks, by 2.70 m long strides and 4.36 strides/s frequency. At the maximal velocity, his contact and flight times were 86 and 145 ms, respectively, and vertical ground reaction force generated equalled 4.2 times his body weight (3932 N). The braking and propulsion phase represented 37% and 63% of ground contact, respectively, with his centre of mass (CoM) exhibiting minor reductions in horizontal velocity (2.7%) and minimal vertical displacement (4.9 cm) emerged Bolt's maximal sprint velocity and international predominance from his coordinated motor abilities, power generation capacities, and effective technique. This study confirms that his maximal velocity was achieved by means of relatively long strides, minimal braking phase, high vertical ground reaction force, and minimal vertical displacement of CoM. This study is the first in-depth biomechanical analysis of Bolt's maximal sprinting velocity with the segmental reconstruction. [ABSTRACT FROM AUTHOR]