Add Darrelle Revis to the list of superstar players who have suffered a non-contact ACL injury in recent years. Sunday's injury effectively ended the premier cornerback's season just three weeks in. It's the same kind of ACL injury that forced league-leading wide receiver Wes Welker out of action back in 2009 and ended wideout Kenny Britt's 2011 season.
What's causing these non-contact ACL tears? First, let's examine the circumstances surrounding each of the injuries:
- While in pursuit of a reverse screen play, Revis planted on his left leg to cut right and avoid a cut block. His left foot appeared to point inward when he planted, and when he pushed off, his left knees caved in toward the ground.
- Welker's injury was double the catastrophe, as he tore both the ACL and MCL in his left knee. The star slot receiver caught the ball over the middle and turned upfield, running directly at the pursuing tackler to execute a double cut (planting off the left foot and breaking to the right). Welker struck the ground with the side of his left foot, causing his knee to bend inward, resulting in the devastating injury.
- Britt's injury was slightly different from Revis's and Welker's, since he first absorbed contact. Britt hauled in a catch and spun off a would-be tackler. Upon breaking out of the spin move, he planted off his left foot to run right. When he drove his right foot into the ground, his toes appeared to point outward, and his right foot wasn't aligned with his knee.
Although this is not a detailed kinesiological analysis, the three injuries have one thing in common: a breakdown of proper running mechanics when the player's foot strikes the ground. In each occurrence, the foot was not in full contact with the ground during the cut, and the toes were not pointed straight ahead.
When an athlete's ankle and foot are not pointed straight when executing a cut, he or she is in serious jeopardy of suffering an ACL tear. That's correct foot alignment should be a major point of emphasis during speed and agility training.
Several speed drills reinforce correct mechanics. One is the Side Shuffle to Forward/Backward Lunge, as demonstrated by Pro Bowl RB Ryan Mathews. Watch the video above to learn more about the exercise, and check out other drills that train proper foot and knee alignment when running, cutting and changing direction.
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