@article{Sauren_Lieby_schmidt_2010, title={Motion Analysis of the 2009 Men’s 100 m World Record}, url={https://ojs.dpg-physik.de/index.php/phydid-b/article/view/120}, abstractNote={<p class="MsoNormal"><span style="mso-ansi-language: EN-US;" lang="EN-US">The fabulous 100 m world record of Jamaica’s Usain Bolt (9.58 s on Aug. 16<sup>th</sup>, 2009, in Berlin) has intrigued not only sports fans. It can also be fruitfully used in physics teaching as a real life event, although there are some caveats.</span><span style="mso-ansi-language: EN-US;" lang="EN-US"></span></p> <p class="MsoNormal"><span style="mso-ansi-language: EN-US;" lang="EN-US">After downloading public-domain, high-resolution renditions of the record race for a motion analysis, we first used video-cutting software to clock individual frames when the winning athlete passed the ten 10 visible on-track markers. A polynomial fit of these data was possible with r<sup>2 </sup>= 0.9998, however, it failed to produce physically plausible velocities and accelerations.</span><span style="mso-ansi-language: EN-US;" lang="EN-US"></span></p> <p class="MsoNormal"><span style="mso-ansi-language: EN-US;" lang="EN-US">Data published by the IAAF, when evaluated in the same way, did not produce these artifacts, and showed the record-breaking dash to be composed of a 3-second phase with decreasing acceleration, followed by a high-speed phase peaking at 44,2 km/h near 7,5 s. A slight deceleration at the very end can be used as an estimate for still further improvements of the 100 m world record, as had been down before.<sup>1</sup> The relevance of the results w.r. to biokinematics as well as training methods are discussed.</span><span style="mso-ansi-language: EN-US;" lang="EN-US"></span></p> <p class="MsoNormal"><sup>1</sup>H.K. Eriksen et al., Am. J. Phys <strong style="mso-bidi-font-weight: normal;">77</strong>, 324 (2009)</p>}, journal={PhyDid B - Didaktik der Physik - Beiträge zur DPG-Frühjahrstagung}, author={Sauren, Johannes J.A.M. and Lieby, Benjamin and schmidt, Elmar}, year={2010}, month={Okt.} }