The experimental group will receive a four-week "CTAR exercise protocol " and routine dysphagia care.

The control group will only receive routine dysphagia care.

The experimental group will receive a four-week CTAR protocol and regular dysphagia care, while the control group will only receive routine dysphagia care. The routine dysphagia care is including dysphagia education, dietary precautions, oral hygiene, and swallowing training, etc. The CTAR protocol is first, the study nurses face-to-face teach dysphagia patients to perform CTAR exercises once, then the patient perform CTAR exercises three times a day, five days a week, and for four weeks. The CTAR exercise is to tighten a rubber ball which placed between the chin and the sternum, and to perform 3 cycles of isometric exercise and isotonic exercise.

The functional oral intake scale (FOIS) is a 7-point scale, which is used to measure the state of eating by mouth. A score of 1 means that patient can't eat by mouth at all, and a score of 7 means patient can eat food of any stickiness and type by mouth. The research nurse will use this scale to test the state of eating by mouth of participants, and collect the pre-test and four-week post-test data then record on an excel dataset.

The penetration-aspiration scale (PAS) is an 8-point scale used to measure laryngeal leakage and aspiration severity, which with higher scores representing more severe respiratory aspiration. A score of 1 means that normal swallowing function, and a score of 8 means food mistakenly enters airway and without cough re¬flex during swallowing. The research nurse will use this scale to test the laryngeal leakage and aspiration severity of participants, and collect the pre-test and four-week post-test data then record on an excel dataset.

The modified water swallowing test (MWST) is a 1 to 5-point scale, which is a routine used clinical swallowing test. The researcher nurse will inject 3ml of cold water into the bottom of the participant's mouth with an injection syringe, and then asks the participant to swallow the water for the swallowing test. If the participant is unable to swallow, or experienced dyspnea, coughing, or wet-hoarse dysphonia after swallowing, a score of 1-3 will be respective recorded. The lower the score, meaning the more serious problem of swallowing and choking. The sensitivity and specificity of MWST to differentiate between aspirators and non-aspirators with a cutoff level of 3 are 70 and 88%, respectively. The research nurse will use this scale to test the water swallowing function of participants for a screen scale of inclusion criteria, and collect the pre-test and four-week post-test data then record on an excel dataset.

Based on the pre- and post-test scores of the modified water drinking test, the researcher will calculate the number of participants who have present improved at post-test scores, and then calculate the swallowing improvement rates of the two groups. The formula is: The swallowing improvement rate= Number of participants with improve events (modified water swallowing test showed the post-test score is improve compare to pre-test) ÷ number of participants of each group × 100%.