Head, Neck and Jaw training is a good way to allow your athletes to recover from other workouts like squats.

While one athlete squats, another can be on the back side of the squat rack training the head, neck and jaw. 

Using a resistance band attached to both sides of the rack, properly place it under the athlete's jaw, making sure it is not too high.

The athlete will then open and close his mouth to perform the reps. 

Note: there should be no clicking in the jaw. If there is, adjust the resistance of the band being used.

Courtesy of Rogers Athletic