The Effects of Mouth Guards and Clenching on Strength and Power Measures of a Countermovement Vertical Jump: A Pilot Study

Strength and power gains from either mouth guards or clenching have been reported in highly trained athletes from a number of studies utilizing different testing measures. However, there have not been statistically significant effects in a recreationally trained population; and there has not been a research design to combine multiple mouthpiece conditions (mouthpiece designed for performance, a traditional mouth guard, and no mouthpiece condition) with a clench and no clench sub-condition. Therefore, the purpose of this study was to evaluate potential ergogenic effects of mouth guards and clenching on strength and power measures of a countermovement vertical jump. Three recreationally trained males (age 26.7 ± 2.9 years, mass 89.2 ± 10.8 kilograms, and height 182.0 ± 2.9 centimeters) volunteered to participate in three testing sessions, one session for each condition, each separated by one week. The three conditions consisted of a traditional, boil-and-bite mouth guard (MP), a mouthpiece designed for performance (PMP), and no mouthpiece (NoMP). The order of conditions was randomly assigned to participants, and each condition consisted of both a maximal clench and no clench sub-condition, allowing each participant to serve as his own control. Each testing session consisted of a warm up followed by a countermovement vertical jump test performed from a force platform (to gather dependent variables: peak vertical force, normalized peak force, and rate of force development) using a Vertec to measure the final dependent variable: vertical jump height. There were no statistically significant differences (p\u3e.05) between conditions for peak force, normalized peak force, or rate of force development. Significant differences in vertical jump height (p\u3c.05) were observed for overall main effect of mouthpiece type and interaction; however post hoc analysis revealed that there were no significant differences between individual conditions. There were no negative effects of either mouthpiece condition when compared to no mouthpiece nor were there for clenching when compared to no clenching. Therefore, this study cannot recommend traditional boil-and-bite mouth guards or performance designed mouthpieces to positively affect strength and power. Likewise, clenching cannot be recommended because further research is necessary with a larger number of participants to come to further conclusions