 This randomized controlled trial will include 60 patients preparing to undergo alloHCT 30 in the intervention group, 30 in the control group. We plan to analyze the effect of IETMA on VO2peak. Subjects will be recruited after their transplant teams have determined that they will undergo alloHCT within the subsequent 5-12 weeks. Following recruitment, patients will undergo baseline fitness assessments consisting of cardiorespiratory exercise testing using indirect calorimetry on a cycle ergometry for the assessment of VO2peak, 6 minute walk distance testing, and baseline physical activity, symptom and quality of life questionnaires. Participants randomized to the IETMA group will then receive an individualized IETMA prescription for a duration of at least 5 weeks, up until the time of admission for alloHCT or 12 weeks from the initiation of IETMA, whichever occurs first. The mode of exercise can be walking, jogging, running, cycling, elliptical, stair climbing, or a combination of these, and will be performed unsupervised at home. For the first week, participants will be asked to engage in 30 minutes of aerobic exercise at any intensity for 3-4 days. For weeks two and beyond, participants will undergo 3-4 sessions of IET, consisting of a 5 minute warm-up and five 2-minute intervals, with the goal of reaching 80 MHR, separated by 3 minutes of recoverylight activity in between each interval. Each exercise session is a total of 30 minutes. Fitness assessments will be completed at the end of the intervention period, at the time of admission for alloHCT. Based on the improvement in VO2peak seen in the pre-alloHCT patient population in LCCC 1311, the current study is powered to detect a 3.8mlkgmin VO2peak improvement in the intervention group relative to the control group. 