Introduction: Interventions for older adults with multiple medical diagnoses may need to have a more general focus that can be applied across a broad range of medical conditions. Ba-Duan-Jin (BDJ), a non-disease specific Tai Chi-QI Gong based mind-body training coordinated with deep breathing, may be a good choice. Case Description: A 79-year-old white female patient, with diagnoses of cardiopulmonary, gastrointestinal, and perceived sleep dysfunctions, was referred for consultation of geriatric rehabilitation for poor endurance and balance in a senior living retirement complex where rehabilitation services were provided. A BDJ-based deep diaphragmatic breathing (DDB) progressive training was provided 45-50 minutes each time and 3 times a week for 6 months. At the baseline, the end of 3rd and 5th month of this study, this patient was assessed with the Barthel index for activity of daily living, 1-minute heart rate recovery, Pittsburg sleep quality index, head elevation during sleeping, 4-stage balance, and 2-minute walk test. At the end of 3rd and 6th month, the patient was able to have improved strength, endurance, balance, cardiorespiratory function, gastral regurgitation, and activities of daily living. The mechanism of the beneficial effects of BDJ-based deep breathing in this case was discussed with body mechanical and anatomical consideration. KEY WORDS: Older adults, Ba-Duan-Jin, Tai Chi, Multimorbidity, Diaphragmatic anatomy.