Attaining and Maintaining Isometric and Isokinetic Goals of the Shaker Exercise

Abstract

Previous studies have shown that the Shaker Exercise is effective in restoring oral intake in patients with deglutitive failure due to upper esophageal sphincter (UES) dysfunction. Our aim was to determine (1) exerciser compliance among healthy older adults, (2) number of days required to attain the isometric (IM) and isokinetic (IK) exercise goals, (3) rate and reason for dropout of exercisers, and (4) complaints associated with performance of the exercise. Twenty-six nondysphagic older adults were enrolled from an independent-living community (66-93 yr) to perform the Shaker Exercise. Each participant completed a questionnaire on exercise performance and its associated difficulties three times a day for six weeks. Four randomly chosen nondysphagic participants underwent pre- and postexercise videofluoroscopic swallow studies for biomechanical measurements. Maximum anterior hyoid and laryngeal excursions, as well as maximum anteroposterior UES opening increased (p<0.05) following exercise. Duration to attain Shaker Exercise performance goals varied among participants. IK was more easily attained than IM. Only 50% and 70% of those enrolled initially were able to complete the exercise duration and attain its IK and IM goals, respectively. However, those who stayed in the program attained the IK and IM goals (100% and 74%, respectively). Most dropouts occurred in the first two weeks of exercise. Performance of the exercise was associated with mild muscle discomfort that resolved spontaneously after a couple of weeks. We concluded that although the Shaker Exercise can be performed independently, a structured and gradually progressive program is needed to attain the exercise goals completely.