Not Enough Fat

Players flunk their physicals and conditioning drills all the time at training camp. No team is immune to this. RB Joe McKnight of the New York Jets failed his physical initially, but passed it on a second attempt.

He had difficulty completing drills the other day and was forced to sit out some of the snaps. It turns out that his body fat was too low at 3.3%. The training staff wants him to get it up to 6%.

Players come in all shapes and sizes. Some of the biggest players have low rates of body fat. It can get too low and cause problems like it did in McKnight's case.