According to a BBC report, scientists have calculated that less than 8% of Usain Bolt’s running effort goes to motion and the rest overcomes aerodynamic drag.
The team calculated that Bolt’s maximum power occurred when he was less than one second into the race and was only at half his maximum speed. This demonstrates the near immediate effect of drag, which is where air resistance slows moving objects.
They also discovered less than 8% of the energy his muscles produced was used for motion, with the rest absorbed by drag.
When comparing Bolt’s body mass, the altitude of the track and the air temperature, they found out that his drag coefficient – which is a measure of the drag per unit area of mass – was actually less aerodynamic than that of the average man.
OCW and MITx offer great opportunities to better understand the often surprising field of aerodynamics, including OCW’s 16.100 Aerodynamics materials and the upcoming MITx MOOC 16.101x Introduction to Aerodynamics.