Ultrasound in Evaluating Muscle-Glycogen Content in Cancer Patients

PRIMARY OBJECTIVES: I. Determine feasibility of using non-invasive MuscleSound technology to determine glycogen stores in cancer patients. EXPLORATORY OBJECTIVES: I. Determine the baseline glycogen storage in two different groups of cancer patients, who are undergoing inpatient rehabilitation: (1) those with cachexia; (2) those without cachexia. II. Determine the rate of depletion of muscle-glycogen stores by calculating the "Fuel Rating" score (FRS) at baseline, after 10-min of exercise and then again after 20-min of exercise. III. Determine if there is any correlation between muscle-glycogen (at baseline and its depletion rate over time) and other factors including cancer type, cancer stage, patient age, patient sex, current body mass index (BMI), presence or absence of cachexia, functional measures and patient reported outcomes. OUTLINE: Patients undergo ultrasound via MuscleSound technology over 3 minutes at baseline and immediately after each of 2 physical therapy sessions comprising cycling or walking over 10 minutes.