Long-term effects of high-intensity interval training in heart transplant recipients: A 5-year follow-up study of a randomized controlled trial.

Abstract

Previous studies have demonstrated that high-intensity interval training (HIT) is superior to moderate-continuous exercise in general and in cardiovascular diseases. Recently, we also found HIT safe and efficient after heart transplantation (HTx). This study reports the 5-year long-term effects. Forty-one HTx patients who had completed the previous 12-month randomized controlled trial, comparing HIT intervention with usual care, were eligible. In particular, we measured VO2peak , muscular capacity, intravascular ultrasound, and questionnaires measuring physical and mental health. The baseline mean±SD values were as follows: age; 49.1±16.5years, men; 68%, time since HTx: 4.1±2.2years. Within the HIT group, initial VO2peak increased significantly from 27.7±5.7 to 31.2±5.3mL/kg/min. However, during the next 4years, VO2peak decreased to 26.0±6.2mL/kg/min. The control group showed slightly decreasing VO2peak values during the entire 5-year period. The HIT group reported significantly less anxiety symptoms, but there were no long-term differences in VO2peak , muscular capacity, or cardiac allograft vasculopathy between the groups. The similar VO2peak values correspond to our findings of similar everyday activity. Our findings suggest that intermittent periods of HIT may be necessary to maintain the initial benefits gained from the intervention. However, HIT probably reduces the burden of anxiety, which is a frequent health issue following HTx.