Lately the use of mouth guards has gone from an on-field protective device to a performance device in the gym. A new study from the University of Connecticut, Storrs, reports that weight-trained collegiate athletes wearing a Power Balance mouth guard had more power and force when doing the bench-press throw on a Smith machine. The more weight you lift, the more overload you can place on the muscle, which can help to encourage muscle growth. So in addition to a weight belt, wrist straps, and knee wraps, another tool you might want to throw in your gym bag is a performance mouth guard, such as the Power Balance mouth guard (powerbalance.com).
REFERENCE: C. Dunn-Lewis et al., J Strength Cond Res., 26(4):1085–93, 2012.