Intervention: Participants will be randomized to 4 groups: 1 - Physician monitored, 2 - Family monitored, 3 - Self monitored, and 4 - Control. Participants from all groups will perform aerobic testing at baseline and 3 months, complete an online questionnaire at baseline, 6 weeks, and 3 months, and wear an accelerometer for 1 week at baseline, 6 weeks and 3 months. Participants in Group 1,2,and 3 will receive a Fitbit activity tracker and wear it for 3 months. Weekly Fitbit reports are automatically sent to the individual participants in all groups. Group 1 participant Fitbit reports will also be sent to their Physician. Group 2 participant Fitbit reports will also be sent to their partner/spouse. Group 3 participants will have sole access to their weekly Fitbit results. Group 4 is the control group and will not receive a Fitbit.