As the key player in most passing plays, Brown needs to be able to catch a football from any angle. This obviously requires sharp hand-eye coordination. “Part of my training for that is getting my body in different positions and trying to catch the ball,” he says. That typically involves practicing over-the-shoulder catches, single-leg catches, turning catches and so on.

But completing a catch also demands complete core control. And sometimes using just one hand. That’s why Brown’s trainer, Cara Troutman-Enseki, focuses on strengthening his core in a destabilizing position, which is how she came up with the idea of having him hold a forearm side-plank while catching passes with his top hand.

“We use a football to make it sport specific,” says Troutman-Enseki, director of exertion rehabilitation for the UPMC sports medicine concussion program (she met Brown in January of 2016 when he came to her after getting a concussion and has been training him up to five times a week ever since). She has him do three sets of 15 reps per side once a week. “This allows us to work on destabilizing his core for up to five minutes,” she says.

Though nothing but his top arm moves while he’s executing it, the drill strengthens his whole body. “It works his entire core — the transverse and rectus abdominis, external and internal obliques and erector spinae — as well as the traps, delts, rotator cuffs, rhomboids, pecs, serratus anterior, glutes, quads and adductors,” says Troutman-Enseki.