Comparison of three different types of exercises for selective contractions of supra- and infrahyoid muscles

Min Cheol Chang,Byung Joo Lee,Kwanmyung Kim,Jong-Moon Hwang,Sungwon Park,Joo Young Cho,Donghwi Park

doi:10.1038/s41598-021-86502-w

Abstract

Several exercise methods, such as the Shaker exercise, tongue press exercise, chin tuck against resistance (CTAR) exercise, and submandibular push exercise, have been introduced to strengthen the muscles involved in swallowing. In this study, we compared the effectiveness of the CTAR, submandibular push, and Shaker exercises for the induction of selective supra- and infrahyoid muscle contractions using surface electromyography (EMG). This study is a prospective non-randomized controlled study. Twenty-five healthy subjects and 20 patients experiencing swallowing difficulty were enrolled. During the three different types of exercises, the root mean square (RMS) values of the sternocleidomastoid (SCM), suprahyoid (anterior belly of the digastric and mylohyoid muscles), and infrahyoid (sternothyroid and thyrohyoid muscles) muscles were analyzed using surface EMG. Differences in the activity of swallowing muscles among the three different exercises were analyzed using one-way repeated measured analysis of variance. In terms of both the maximum and mean RMS values of the suprahyoid muscle, the submandibular push exercise showed a larger RMS value than the CTAR and Shaker exercises in healthy subjects (p < 0.05). In terms of both the maximum and mean RMS values of the suprahyoid muscle, the Shaker exercise and submandibular push exercise showed a larger RMS value than the CTAR exercise in patients with swallowing difficulty (p < 0.05). The submandibular push exercise may be effective as a swallowing muscle exercise owing to its superiority in inducing selective contractions of the supra- and infrahyoid muscles. The CTAR and Shaker exercises are also effective in this regard.

Highlights

The swallowing process is a compound sensori-motor behavior that includes the coordinated relaxation and contraction of the muscle tissues around the tongue, mouth, pharynx, larynx, and upper esophagus[1,2,3]
The muscles involved in swallowing can be strengthened using several exercise methods, such as the Shaker and tongue press exercises, chin tuck against resistance (CTAR) exercise, and submandibular push exercise[20,21]
We examined the effectiveness of the submandibular push exercise for the contraction of muscles involved in swallowing without a pressure sensor, in order to determine its usefulness as an at-home exercise

Summary

Introduction

The swallowing process is a compound sensori-motor behavior that includes the coordinated relaxation and contraction of the muscle tissues around the tongue, mouth, pharynx, larynx, and upper esophagus[1,2,3]. In patients with swallowing difficulty, Gao and Z hang[24] reported similar effects in improving swallowing dysfunction between the CTAR and Shaker exercises Both exercises involve neck flexion movement patterns, which induce unnecessary contractions of the sternocleidomastoid (SCM) muscle and may adversely affect contractions of the selective supra- and infrahyoid muscles[25]. The application of the submandibular push exercises in patients who constantly need dysphagia treatment may have some limitations Based on these observations, we examined the effectiveness of the submandibular push exercise for the contraction of muscles involved in swallowing without a pressure sensor, in order to determine its usefulness as an at-home exercise. Based on previous research results, we postulated that compared to the CTAR and Shaker exercises, the submandibular push exercise would induce selective contraction of the supraand infrahyoid muscles without unnecessary SCM contraction. By comparing three different exercises, we attempted to determine the effects of each of the three different exercises on each swallowing muscle in healthy subjects and patients with swallowing difficulty

Results

Discussion

Conclusion