F-12M Free Communication/Poster Exercise Testing
Several studies have shown that teeth clenching (TC) increases isokinetic peak torque. However, little is known about the specific effects on each repetition during repeated muscle actions.
To determine the effects of TC with moloar-protector on force production during maximal repeated isokinetick knee extension.
Seven men (20.0±0.4years, 63.3±7.3kg) and five women (20.0±0.5years, 56.4±2.1kg) collegiate level table tennis players volunteered for the study. Each subject performed ten maximal repeated knee extensions with their dominant leg at angular velocities of 60, 120, and 300°s−1 with TC using molar protecting type mouthpiece (Sporteeth) or in relaxed mandibular position without TC (control condition) using a System 3 Biodex. Treatments were balanced and randomized. Peak torque per body mass (PT/BM), maximum work per body mass (MW/BM), and total mork per body mass (TW/BM) were evaluated over ten repetitions. PT/BM and work per body mass (W/BM) were evalutated for each repetition. Paired t-test with alpha level corrections were used to analyze the differences between TC and without TC.
There were no significant differences in PT/BM, MW/BM, and TW/BM between TC conditions at all velocities. However, PT/MB and W/BM in the 9th and 10th repetitions at 60°s−1 with TC were significantly (p ≤ 0.05) higher than without TC by 9% and 6%, respectively. PT/BM in the 4th, 6th, and 8th repetitions and W/BM in the 5th and 8th repetitions at 120°s−1 with TC significantly higher than without TC by 5%, 6%, 6%, and 6% and 5% respectively. No significant differences were observed in any repetitions at 300°s−1.
Maximum voluntary teeth clenching with the use of molar-protector can enhance the peak torque and prevent the force reduction from the middle to the last few repetitions of a repeated effort set of 10 repetitions at slow to moderate velocities. Supported by Medical Databank Inc., Osaka, Japan