Inclusion Criteria:  Diagnosed with multiple myeloma >= 18 years old Self-reported as pre-frail or frail (i.e. Fried Criteria: clinically underweight and exhibiting exhaustion, low energy expenditure, slow walking speed, and muscle weakness), with the presence of 2/5 indices classified as pre-frail and >= 3/5 indices classified as frail Has undergone autologous stem cell transplant (ASCT) within 30 and 180 days prior to registration Physically able and willing to complete all study procedures English-speaking  Exclusion Criteria:  Have clinically significant/active cardiovascular disease (e.g. unstable angina, uncontrolled arrhythmia, etc.) Have contraindications to exercise (acute infectious disease or unstable bone lesions) Currently recovering from a recent injury or have been physically injured in the past 6 months, in which participation in rigorous exercise may not be appropriate Participate in regular, structured exercise (> 60 minutes/week) Female patients who are pregnant or planning to become pregnant