Achilles had his heel, Harry Kane has his ankles — even the greatest have physiological limits.
Except those flaws are often what make them great.
Greek mythology tells it that Achilles, a Greek war hero, was held by the back of his foot when dipped in the River Styx, separating the lands of the living and the dead, as a child. This turned him invincible, barring the spot which carries his name, and (how’s your luck?) where he was killed after being struck there by an arrow.
Since 2016-17, ankle injuries have bedevilled Kane’s career on seven different occasions. He tore ligaments there in 2018-19, and combined has missed a full league season’s worth of games through those issues.
And yet, the same physiology that predisposes him to these ankle problems explains his world-class ball-striking and outstanding goalscoring records: the England team’s all-time top scorer, one of only three players with more than 200 Premier League goals, the best debut season (in terms of goalscoring) in Bundesliga history.
The Athletic spoke to football biomechanist Archit Navandar to understand what he calls Kane’s “floppy ankles”, and why they make him so good.
First, a lesson in physiological and biomechanics.
The human ankle is a complex thing, the point where the shin bone (tibia), calf bone (fibula), and talus (heel) meet. Scientists call it a ‘hinged synovial joint’ because movement primarily occurs in one plane (direction). In this case, up and down. The ankle can flex the foot towards the body (dorsiflexion) and extend away from it (plantarflexion) but with limited rotation. Synovial refers to the fluid in the joint, which aids movement.
“We don’t have the same ability that we have with our hands that we have with our feet,” says Navandar. “We don’t have that same dexterity. It’s very easy to rotate our wrists. An ankle, to have the same level of dexterity, you need to train. Rotation is very, very difficult because the stiffer your ankle is, the more control you have in your kick.”
Watchers of Premier League football on UK broadcasts will know analyst Ally McCoist’s fondness of saying a player has “picked the wrong (golf) club” when they mishit a pass. The golfing analogy serves to describe how different passes (and shots) need specific amounts of power/spin and different trajectories. To change the ‘golf club’, players “change the orientation (of the foot),” says Navandar. “A small modification can completely change my surface area of contact.”
Navandar says Kane does it better and more often than most, which makes him unpredictable.
“He gets a lot of power in his kicks but with seemingly no backlift,” says Navandar. “He doesn’t bend his knees as much, it’s not a prominent knee flexion before the kick. There are kicks where there is hip extension, but it’s not prominent. What you want to do when you kick is to increase the surface area of contact to help with the maximum transfer of energy from the foot to the ball because there is going to be some energy loss.”
