若年成人における口唇抵抗トレーニングが口唇強度に及ぼす影響

Effect of Lip-seal Resistance Training on Lip-seal Strength in Young Adults.

抄録

口唇裂強度は、両唇の調音、食事中の食物の捕捉、嚥下前の口腔内の液体維持、および嚥下圧の達成に重要である。本研究の目的は、若年成人における口唇抵抗トレーニングが口唇強度に及ぼす影響について調査することであった。参加者は26～34歳の若年健康成人15名で、全員総入れ歯であった。各人には、市販の口唇抵抗トレーニング用器具を用い、平日週5回、4週間の口唇抵抗トレーニングを実施させた。器具は口の正中線、左角、右角に置き、それぞれ前方、左方、右方に引っ張った。参加者はトレーニング器具を力強く引きながら、器具が唇から出るまでできるだけ強く唇を合わせて抵抗することを要求された。訓練前と訓練後に測定器を用いて口唇閉鎖力を測定した．トレーニング前後のリップシール強度の変化はWilcoxon signed rank testを用いて分析した。平均口唇強度はトレーニング前8.9±1.5N，トレーニング後10.4±1.8Nであった．トレーニング前後でリップシール強度に有意差が認められ（p=0.003），トレーニング期間中の平均増加率は18.1±17.6％であった．この結果から、4週間のリップシール抵抗トレーニングにより、若年成人のリップシール強度が増加することが示された。これらの結果から、前方だけでなく、両側から引っ張るトレーニングは口輪筋を強く刺激し、結果として口輪筋力の増加をもたらすことが示唆された。

Lip-seal strength is important for articulating bilabials, capturing food during eating, maintaining fluid within the oral cavity before swallowing, and achieving swallowing pressure. The objective of this study was to investigate the effect of lip-seal resistance training on lip-seal strength in young adults. The participants comprised 15 young healthy adults aged 26-34 years, all with complete dentition. Each was required to perform lip-seal resistance training 5 weekdays a week for 4 weeks with a commercially available instrument for that purpose. The instrument was placed on the midline, left corner, and right corner of the mouth, and pulled forward, leftward, and rightward, respectively. The participants were required to pull the training instrument forcefully while resisting by closing the lips together as strongly as possible until the instrument exited the lips. Lip-seal strength was measured at before and after training using a measurement device. Change in lip-seal strength between before and after training was analyzed using the Wilcoxon signed rank test. The mean lip-seal strength was 8.9±1.5 N before training and 10.4±1.8 N after. A significant difference was observed in lip-seal strength between before and after training (p=0.003), and the mean increase during the training period was 18.1±17.6%. The results showed that lip-seal resistance training for 4 weeks increased lip-seal strength in young adults. These findings suggest that training that involves pulling not only in a forward direction, but also in bilateral directions strongly stimulates the orbicularis oris muscle, resulting in an increase in lip-seal strength.