Evaluation of the Effectiveness of a Muscle Strengthening Protocol as an Adjunct to Rehabilitation Training in Patients With Heart Failure

Background Heart failure is a syndrome characterized by reduced cardiac output and/or increased ventricular filling pressures, leading to functional impairment, commonly manifested by dyspnea and reduced exercise tolerance. Traditional cardiac rehabilitation mainly relies on pharmacological therapy and aerobic training aimed at improving cardiovascular performance. However, increasing evidence highlights the role of peripheral factors, particularly skeletal muscle dysfunction and systemic inflammation, in limiting exercise capacity. Recent studies and meta–analyses suggest that combined aerobic and resistance training provides greater benefits in muscle strength and quality of life than aerobic training alone. Objective To evaluate the effectiveness of a muscle–strengthening protocol as a complement to traditional rehabilitation training in patients with heart failure, focusing on the impact of a multi–joint exercise such as the progressive load box squat on physical performance and quality of life. Methods Twenty–two clinically stable patients with chronic heart failure, of both sexes, independent in daily activities and enrolled in a rehabilitation program, were included. Assessments at admission and discharge comprised the Short Physical Performance Battery (SPPB), the 6–Minute Walking Test (6MWT), and handgrip strength. The experimental group performed aerobic exercise, calisthenics, and daily box squat training. Load progression was applied using a weighted vest from 0% to 10% of body weight over six consecutive days. Each session consisted of five sets of five repetitions, with a maximum recovery of four minutes between sets. Statistical analysis was conducted using repeated–measures ANOVA, with p ‹ 0.05 considered significant. Results Patients undergoing the combined protocol showed significant improvements in SPPB strength–related components and 6MWT performance. A positive trend was also observed in exercise tolerance and perceived well–being. Conclusions The integration of multi–joint strength exercises, such as box squats, into cardiac rehabilitation programs for patients with heart failure appears effective in improving physical performance and quality of life. Further studies with larger samples and longer follow–up are needed to confirm these findings.