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Updated: Jun 28, 2026
08:27
A Real-World High-Intensity Interval Training Protocol for Cardiorespiratory Fitness Improvement
Published on: February 22, 2022
High-Intensity Interval Training vs Moderate Continuous Training in Adults With Congenital Heart Disease: A
Ruochen Tony Mao1, John Philip Willner2, Stephen Pylypchuk1
1Division of Cardiology, Department of Medicine, Faculty of Medicine, University of Alberta, Edmonton, Alberta, Canada.
The Canadian Journal of Cardiology
|June 26, 2026
Summary
High-intensity interval training (HIIT) and moderate continuous training (MCT) safely improved exercise capacity in adults with congenital heart disease (ACHD). HIIT showed a greater increase in peak oxygen uptake and an adaptive increase in left ventricular mass.
Area of Science:
- Cardiology
- Exercise Physiology
- Rehabilitation Medicine
Background:
- Adult congenital heart disease (ACHD) is characterized by reduced exercise capacity, impacting prognosis.
- Optimizing exercise capacity is crucial for managing ACHD patients.
Purpose of the Study:
- To compare the efficacy of high-intensity interval training (HIIT) versus moderate continuous training (MCT) in enhancing exercise capacity in ACHD patients.
- To assess the safety and impact of these training modalities on cardiac structure and function.
Main Methods:
- A 3-arm randomized controlled trial involving 32 ACHD patients over 12 weeks.
- Interventions included HIIT, MCT, and a control group.
- Primary outcome was the change in peak oxygen uptake (V˙O2); secondary outcomes included adverse events, cardiac remodeling, and quality of life.
Main Results:
- Both HIIT and MCT significantly increased peak V˙O2 compared to the control group.
- HIIT demonstrated a greater improvement in peak V˙O2 (3.7 mL/kg/min) than MCT (2.1 mL/kg/min).
- No adverse events were reported; HIIT led to an 8% adaptive increase in left ventricular mass without adverse cardiac remodeling.
Conclusions:
- Both HIIT and MCT are safe, feasible, and effective in improving exercise capacity in ACHD.
- HIIT offers a potential advantage for enhancing cardiorespiratory fitness in this population.
- HIIT-induced left ventricular mass increase is adaptive and should be considered in cardiac rehabilitation programs.
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