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Andre De Grasse's unconventional frame, style and success intrigue scientists
Canadian sprinter Andre De Grasse is drawing plenty of (sometimes incorrectly-attributed) attention for his success in Rio, which includes a bronze in the 100 metres and a place in Thursday night's 200-metre final, and there have also been plenty of stories about his friendly-but-competitive relationship with Usain Bolt. Watching him and Bolt race brings up questions about how two guys with such disparate bodies can be two of the world's best sprinters: Bolt is 6'5'' and 207 pounds, while De Grasse is 5'9' and 154 pounds. Peter Weyand, a professor of applied physiology and biomechanics at Dallas' Southern Methodist University, told Rachel Brady of The Globe and Mail that it's likely about the mechanics in how they strike the ground:
“What makes elite sprinters elite is how forcefully their feet hit the ground in relation to what they weigh,” said Weyand. “Bolt gets a longer step with every stride cycle because he’s so tall. In order to do what Andre does at his height, he has to have great leg mechanics to be able to attack the track. The motion of the leg through the setup phase – as it’s repositioning and then as it first contacts the ground – that’s the time you differentiate speed from one athlete to the next. Elite sprinters attack the ground well and get a bigger force, which makes them go fast. Based on how he races, Andre must be very good at doing that.”
Another interesting element with De Grasse is that he doesn't usually get off to great starts, but is stronger towards the finish. Weyand thinks he can improve his start, while University of Toronto professor David Frost thinks De Grasse's slow starts are about his lack of muscle relative to others::
“The shorter, less massive guys tend to be a bit better out of the blocks, but he’s not – it’s the weakest part of his race, and where he can still get better,” said Weyand. “The curious thing about Andre and the strength of his racing is his top-end speed. He’s so strong in the latter part of the race.”
Some experts who watched Sunday’s race believed that the Canadian sprinter benefits from his smaller, leaner frame down the stretch of races, maintaining his top speed longer than the others.
“De Grasse isn’t carrying the kind of muscle mass that Gatlin does, for instance, so perhaps it’s limiting how he can accelerate out of the blocks. But it seemed down the stretch of the race that De Grasse was able to maintain his velocity for a longer period of time,” said David Frost, assistant professor in the faculty of kinesiology and physical education at the University of Toronto. “It would be interesting to explore whether De Grasse resists becoming as fatigued down the stretch as the other sprinters. Can he maintain the top speed he achieves for longer than the others? Does he contract and relax his muscles quicker than everyone else?”
Former Canadian sprinter and Olympian Anson Henry, currently a digital reporter for CBC, told CBC's Ben Blum earlier this week he thinks De Grasse can improve his transition up to top speed and get even faster
It's a little deeper than what Bolt is saying. It's not his actual start that needs work; it's his whole acceleration from the blocks up into his upright running form. If you watch Andre's races, once he gets upright, that's when he makes his move, but he tends to be behind at the midway point because he is inconsistent in the way he gets from the blocks to his top speed.
If you think of it in the sense of driving a car, not shifting your gears in a consistent and efficient way can cause the car to accelerate slower. That's where Andre is with his acceleration phase right now. That comes with experience, and his coach is really working on his acceleration phase for the whole year.
I had a long chat with his coach Stu McMillan after the race and we had a long talk about all of this. He got Andre mid-year [De Grasse left his coach at USC in the winter], and Stu had told me that he didn't want to adjust too much with him as far as his race execution. It's a touchy thing to mess with in the middle of an Olympic year. It can change your entire race. Stu said that he is excited to do some serious work on Andre's acceleration phase throughout the fall next season to make sure that it becomes much more consistent.
De Grasse has also drawn attention for his asymmetry, which sees his right arm swing back behind him more than his left and more than what others do. He attributes that to a minor hip injury he suffered in childhood, and experts told Brady he should stick with it:
“In most cases, an increased right arm swing compensates for something in the motion of the left leg or hip,” said Reed Ferber, assistant professor of kinesiology at The University of Calgary and director of its Running Injury Clinic. “If you limit that arm swing, whatever is going on in the left leg is no longer being compensated and you could limit the performance of that leg, which could slow him down or pose the risk of injury.
“You should never just force him to start tucking that arm in. You would have to figure out the source of the injury or weakness and solve that, and maybe then that extended arm swing would go away. There’s definitely an asymmetry there, but it’s clearly not hurting his performance.”
“His arm swing is not at all consequential to performance,” said Weyand. “The arms are light pendulums that allow runners to stay balanced as they execute strides. Differences in the arm’s motion and how it’s angled at the elbow really doesn’t matter to the sprinter’s velocity and the interaction between the feet and the ground. Some of the old guard still think arm motion really matters, but most today realize it’s not that consequential. The old guard might have tried to bend a sprinter’s elbow into place, but they wouldn’t have been able to offer much scientific data about why they were doing it.
So, De Grasse's approach is clearly working for him overall, and he may or may not have even more room to improve. It's interesting that so much of his success isn't really definitively explained at this point, though. You can bet that there will be a lot of scientists taking a more detailed look at De Grasse's stature and motion after these Olympics.
