Exercise intensity and cardiac metabolic adaptations in elderly heart failure rehabilitation: A review

Introduction: Heart function depends on efficient cardiac metabolism and energy production. Exercise is vital for supporting these processes, especially in heart failure (HF) rehabilitation, where weakened metabolism and energy deficits are common. Structured exercise improves metabolic efficiency while reducing sedentary behavior, such as prolonged sitting, further supports heart health. Even in regular exercisers, prolonged sitting increases cardiovascular risks. Method: This review analyzed studies from 2017 to November 2024 on how exercise intensity affects cardiac metabolism, energy production, and mitochondrial function in HF patients. Searches were conducted in PubMed, Scopus, and Google Scholar using terms like "exercise intensity" and "cardiac metabolism." Studies focused on metabolic changes and mitochondrial bioenergetics were included; those lacking relevant data were excluded. Results: Structured exercise combined with reduced sedentary time significantly improves heart health in HF patients. Exercise gradually strengthens heart muscle, enhances energy utilization, and improves the heart's ability to handle daily stress. Reducing sedentary behavior complements these effects by lowering cardiovascular risks. Conclusion: Improving heart health in HF patients requires both regular exercise and minimized sedentary time. Physical activities can enhance cardiac metabolism, energy efficiency, and overall heart function, providing an effective pathway for better outcomes.