In a fit of apparent egomania, RW's Kerry claimed he could outrun Usain Bolt over 10K. But is it as absurd as it sounds?
Kerry is already a whole 60 seconds behind. ‘Bolt’s specialist sprint training means that his gait is optimised for speed,’ says Bill Baltzopoulos, Professor of Biomechanics at Brunel University.
‘His powerful knee lift, high heel flicks and strong hip flexors help his feet spend as little time in contact with the ground as possible. Bolt would spend half the time in contact with the floor than Kerry would – around 0.1 seconds per step as opposed to at least 0.2.’
The longer your foot spends on the floor the more impact force you are sending through your body, and the longer it takes for you to lift your foot through the rest of the gait cycle and propel your body forward, says Baltzopoulos.
The ideal scenario is not to sink into the ground and then lift yourself up and off, but to try to have your foot brush the ground briefly on its way through, landing as lightly as possible.
The aim: Reduce your ground contact time
‘Improve your leg stiffness,’ says running coach Scott Mitchell (moveclinics.com). ‘The stiffer your leg during contact, the quicker your landing will be.’
Here’s how: ‘Include some fast running in your training,’ says Mitchell. ‘Once a week, after an easy run, do a set of short sprints – say, 6x60m at full speed. You’ll get even more benefit if you do the sprints on a steep hill. Also, add some plyometrics [jumping drills] to your training.
If you don’t have time to include a separate session in your week then do the drills in the middle of a run: break stride and hop forward on one leg for 20 strides, then hop on the other leg. Gradually build up to 2x30 hops on each leg.’ If you’re bothered about other runners calling the men in white coats when they see you, make sure you do it on one of your more remote runs.