A physicаl therаpist is wоrking with а 90 y.о. patient whо was admitted to the hospital with a urinary tract infection and syncope at home. Resting vitals are: normal sinus rhythm 90 bpm, SpO2 95%, BP 110/60 mmHg. After assisting the patient in ambulating 50' with a rolling walker, they report their rating of perceived exertion (RPE) as 9/10 on a modified scale. Exercise vitals are: sinus tachycardia 170 bpm, SpO2 92%, BP 106/58. What is the most appropriate clinical decision/assessment?