Effect of High-Intensity interval training versus moderate continuous training on 24-h blood pressure profile and insulin resistance in patients with chronic heart failure.

In patients with chronic heart failure (CHF) blood pressure (BP) control, represents a relevant target of management. This study evaluated the effect of different intensities exercise training on 24-h ambulatory BP profile and insulin resistance in patients with CHF. Thirty-six CHF patients with left ventricular ejection fraction <40%, were randomized to high-intensity interval training (HIT) or moderate continuous training (MIT) for 12 weeks. HIT consisted in treadmill exercise at ~75-80% of heart rate reserve (HRR), alternated with active pauses at 45-50% of HRR. MIT consisted in continuous treadmill at ~45-60% of HRR. Peak VO2 and anaerobic threshold increased significantly with both HIT and MIT, without significant differences between the two training programs. 24-h, systolic and diastolic BP decreased with both HIT and MIT. The same occurred for day-time and night-time systolic and diastolic BP. The decrease in day-time diastolic BP was slightly but significantly greater in HIT. Both HIT and MIT induced a significant decrease in fasting glucose and insulin, whereas HOMA-IR decreased significantly only after HIT. In patients with CHF exercise training reduces BP throughout the day, without substantial differences between moderate and more vigorous exercise intensity, with a small exception for day-time diastolic BP. HIT was more effective in improving insulin resistance.