title: Meta-analysis of aerobic interval training on exercise capacity and systolic function in patients with heart failure and reduced ejection fractions.
abstract: It is unknown if vigorous to maximal aerobic interval training (INT) is more effective than traditionally prescribed moderate-intensity continuous aerobic training (MCT) for improving peak oxygen uptake (Vo2) and the left ventricular ejection fraction (LVEF) in patients with heart failure with reduced ejection fraction. MEDLINE, PubMed, Scopus, and the Web of Science were searched using the following keywords: "heart failure," high-intensity interval exercise," "high-intensity interval training," "aerobic interval training," and "high-intensity aerobic interval training." Seven randomized trials were identified comparing the effects of INT and MCT on peak Vo2, 5 of which measured the LVEF at rest. The trials included clinically stable patients with heart failure with reduced ejection fraction with impaired left ventricular systolic function (mean LVEF 32%) who were relatively young (mean age 61 years) and predominantly men (82%). Weighted mean differences were calculated using a random-effects model. INT led to significantly higher increases in peak Vo2 compared with MCT (INT vs MCT, weighted mean difference 2.14 ml O2/kg/min, 95% confidence interval 0.66 to 3.63). Comparison of the effects of INT and MCT on the LVEF at rest was inconclusive (INT vs MCT, weighted mean difference 3.29%, 95% confidence interval -0.7% to 7.28%). In conclusion, in clinically stable patients with heart failure with reduced ejection fraction, INT is more effective than MCT for improving peak Vo2 but not the LVEF at rest.
authors: Faculty of Rehabilitation Medicine, University of Alberta, Edmonton, AB, Canada. mark.haykowsky@ualberta.ca
authors: Mark J
authors: MJ
authors: Haykowsky
authors: Meagan P
authors: MP
authors: Timmons
authors: Calvin
authors: C
authors: Kruger
authors: Margaret
authors: M
authors: McNeely
authors: Dylan A
authors: DA
authors: Taylor
authors: Alexander M
authors: AM
authors: Clark
mesh_terms: D015444:Exercise / Q000502:physiology*; D005080:Exercise Test; D005081:Exercise Therapy / Q000379:methods*; D006333:Heart Failure / Q000503:physiopathology / Q000534:rehabilitation*; D006801:Humans; D010101:Oxygen Consumption; D013318:Stroke Volume; D013599:Systole; D016896:Treatment Outcome; D016277:Ventricular Function, Left; D020257:Ventricular Remodeling