Abstract
We previously reported that several rounds of exercise (isometric contraction) of the anterior neck muscles above and below the hyoid bone and the sternomastoid muscle, while supporting the mandible, can improve the swallowing function. Isometric contraction is a training maneuver expected to increase the muscular strength in short periods of time. Eleven elderly individuals (age : 60-88) underwent self-training with this maneuver immediately before each meal and the efficacy was evaluated 2-3 weeks later. During the analysis of the results, the repetitive saliva swallowing test score changed from 2.7 (± 1.2) before training to 6.2 (± 1.6) after training. On plain lateral neck X-ray, the chin-hyoid bone distance decreased by 11.1% and the chin-thyroid cartilage distance decreased by 8.4%. The sternum-thyroid cartilage distance increased by 12.0%. Therefore, the location of the hyoid bone and thyroid cartilage, which had become closer to the sternum as a result of aging, was corrected to become closer to the chin. This change is expected to improve swallowing by promoting an earlier start of swallowing.
