Superior cardiovascular effect of aerobic interval training versus moderate continuous training in heart failure patients: a randomized study.
Level 2 - randomized trial
Individual randomized controlled trial
PubMed 17548726 · doi:10.1161/CIRCULATIONAHA.106.675041
What was done
Twenty-seven patients with stable postinfarction heart failure on optimal medical therapy (mean age 75.5 ± 11.1 years, mean left ventricular ejection fraction 29%, baseline VO2peak 13 mL·kg⁻¹·min⁻¹) were randomized into three groups for 12 weeks: aerobic interval training (95% peak heart rate, 3 times/week), moderate continuous training (70% peak heart rate, 3 times/week), or a control group receiving standard physical activity advice. Measured outcomes included VO2peak, left ventricular remodeling parameters, pro-brain natriuretic peptide, brachial artery flow-mediated dilation, lateral vastus muscle mitochondrial function, and MacNew quality of life scores.
What was found
VO2peak increased significantly more with aerobic interval training than with moderate continuous training (46% vs 14%, P < 0.001). Left ventricular reverse remodeling occurred only in the aerobic interval training group: end-diastolic and end-systolic volumes decreased by 18% and 25%, respectively, ejection fraction increased by 35%, and pro-brain natriuretic peptide declined by 40%. Interval training also produced greater improvements in flow-mediated dilation and was the only intervention to increase skeletal muscle mitochondrial function. Quality of life increased in both exercise groups, while no changes occurred in controls.
Why it matters
This study demonstrates that high-intensity aerobic interval training is feasible in elderly postinfarction heart failure patients and induces superior cardiovascular and functional adaptations compared to moderate continuous training.
Limits
The sample size was very small (n = 27 across three arms). The study cohort was limited to postinfarction heart failure with reduced ejection fraction, limiting generalizability to other heart failure etiologies. The 12-week intervention assessed surrogate physiological markers rather than hard clinical outcomes such as mortality or rehospitalization.
Cited by
- supports Studies comparing interval training to continuous moderate-intensity training have shown that higher-intensity exercise may produce greater improvements in stroke volume and cardiac output for the same total exercise dose.
- supports Ulrik Wisløff in Norway led pioneering clinical research applying high-intensity interval training to patients with cardiovascular disease.