Combined strength and aerobic training vs. aerobic training alone in patients with heart failure: A systematic review...

Heart failure (HF), characterized by low exercise tolerance, progressive functional decline, and reduced health-related quality of life (HRQoL), affects more than 64 million people worldwide. This study assessed the effects of aerobic training (AT) combined with muscle strength training (combined training) on these health measures in patients with HF across the spectrum of ejection fraction (EF).

A systematic search was conducted across MEDLINE, Embase, Cochrane Central Register of Controlled Trials, CINAHL, SPORTDiscus, Scopus, and gray literature sources. A meta-analysis compared the effects of combined training and AT alone on cardiorespiratory fitness (CRF), 6-min walk test (6MWT) distance, muscle strength, HRQoL, and cardiac function in patients with HF with reduced EF (HFrEF) and those with preserved EF (HFpEF). Pooled estimates were derived using random-effects models, and pre-specified subgroup analyses examined HF classification, exercise volume and type.

Of 13,965 studies screened, 15 were included (n = 526, 17% females; HFrEF: n = 466, 89%; and HFpEF: n = 60, 11%). In HFrEF, combined training increased CRF (standardized mean difference (SMD) = 0.40, 95% confidence interval (95%CI): 0.10‒0.71, p = 0.01, small-to-medium effect), 6MWT distance (mean difference (MD) = 48.4 m, 95%CI: 35.6‒61.0 m, p < 0.001), and upper body muscle strength (MD = 8.3 kg, 95%CI: 3.2 ‒13.4 kg, p = 0.02) more than AT alone. When matched for exercise session duration, combined training increased CRF more than AT alone. High-intensity interval training (HIIT) combined with muscle strength training also showed a greater increase in CRF compared to HIIT alone. There were no differences in HRQoL or cardiac function.

In predominantly male patients with HFrEF, combined training yielded greater improvements in CRF, 6MWT distance, and upper body strength than AT alone. Replacing part of aerobic training with muscle strength training may be an effective strategy to further enhance CRF in HFrEF. Also, HIIT may be combined with muscle strength training to induced further increases in CRF. Further evidence is needed to clarify the effects of combined training in HFpEF.