Purpose: To determine the feasibility of MedBIKE™ in a 12-week home-based high intensity
interval training program in pediatric heart transplant recipients (HTRs).
Hypothesis: The MedBIKE™ intervention will be feasible, with adequate enrolment of
eligible participants (>60%), high session compliance (>80%), and low-drop out rate
(~10%), with no adverse events directly related to the intervention. The investigators
further hypothesize that the MedBIKE™ HIIT intervention will result in immediate and
sustained improvements in exercise capacity, physical activity, self-efficacy towards
physical activity, and HRQoL.
Justification: Clinical trials of exercise interventions in pediatric HTRs remains
significantly lacking. This lack of literature to date has been identified as a
significant knowledge gap in the Canadian Society of Transplantation/CAN-RESTORE recent
joint statement. While the findings to date indicate that exercise interventions in
pediatric HTRs may show improvements in exercise capacity, numerous knowledge gaps
remain. For example, despite promising findings in adult HTRs, HIIT has not yet been
studied in pediatric HTRs. Moreover, the effect of exercise interventions on physical
activity, HRQoL, and self-efficacy towards physical activity have not been well studied.
It is important to evaluate whether a supervised exercise intervention at near-maximal
intensity can promote improvements in physical activity self-efficacy that may in turn
yield sustained improvements in physical activity. One of the limiting factors for
regular participation in post-transplant exercise programs is the necessary time
commitment that is intensified in a program with demographics such as ours in Western
Canada with many post-transplant children living far from the transplant center and with
limited access to exercise facilities. A supervised home-based training program could
optimize the time-efficiency and accommodate the patient's routine schedules. Thus, the
investigators are proposing an assessment of the feasibility of a home-based HIIT
exercise program using a novel telemedicine-enabled video game-linked customizable cycle
ergometer (MedBIKE™).
Objectives: (Primary) Evaluate the feasibility of a 12-week, home-based HIIT MedBIKE™
intervention in pediatric HTRs. (Secondary) Evaluate the impact of the MedBIKE™ HIIT
intervention on 1) exercise capacity; 2) physical activity; 3) self-efficacy towards
physical activity; 4) HRQoL and 5) sustained changes in all secondary outcomes at 6- and
12-months post-intervention.
Research Method: Single-center, randomized crossover feasibility trial with a
multi-method approach. Potential participants and families will be approached first by a
clinical team member. Participants and parents expressing interest will meet with a
research coordinator who, along with one of the investigators and the clinical team will
screen for eligibility. Written consent and assent (if applicable) will be obtained from
participants who are deemed eligible.
Following recruitment, participants will be administered the PedsQL and CSAPPA
questionnaires, an accelerometer will be provided for seven days, and a baseline CPET
will be performed or scheduled to occur following completion of the accelerometer
assessment. Participants will then be randomized via a 1:1 allocation ratio with permuted
blocks of randomly varied sizes either to the immediate MedBIKE™ arm or the immediate
control arm (usual care) for 12-weeks, followed by a repeat assessment. Participants in
the control arm will then cross-over and complete the 12-week MedBIKE™ HIIT program,
followed by a repeat assessment at the completion of the intervention. All
post-intervention assessments will occur 3-7 days post-MedBIKE™ intervention (to allow
adequate recovery) and accelerometers will be programmed to commence counts 24 hours
post-assessment to avoid bias from fatigue from the CPET. Participants will then return
for final assessments at 6- and 12-months post-MedBIKE™ intervention. Whenever possible,
follow-up assessments will be coordinated with clinical appointments (pediatric HTRs are
typically clinically assessed every 3-4 months or more frequently).
The MedBIKE™ program is a first-person interactive videogame in which the participant is
'biking' around a safari collecting animals and will enter a wormhole when completing the
high-intensity exercise portion. The participant and clinician applications are Windows
WPF applications that run on windows 10 PCs. The participant application also includes a
companion app that runs on an Android table. The MedBIKE™ service application is a
platform-independent Python application that is run on a a secure Ubuntu Linux instance
operated by the University of Alberta's Faculty of Medicine and Dentistry IT department.
A follow-up assessment, identical to that of the baseline (questionnaires, CPET,
interviews and a 7-day week wear of an accelerometer) will occur 3-14 days
post-intervention. These assessments will be repeated at 6- and 12-months
post-intervention.
Plan for Data Analysis: The WHCRI biostatistics group will provide statistical and data
analysis support. Continuous data will be summarized as median with first and third
quartiles and changes in pre- and post-intervention measures will be evaluated using the
Mann-Whitney test. Categorical data will be presented by absolute and relative
frequencies (n and %). All statistical analyses will be performed by SAS 9.4 or later
(SAS Institute Inc., Cary, NC, USA).