The effect of phase I cardiac rehabilitation exercise training combined with respiratory training on the Improvement of Cardiopulmonary Function: A Randomized Controlled Trial

When the heart suffers a sudden, severe blockage known as a heart attack, the immediate medical goal is to clear the artery and restore blood flow. This is often done through a procedure where a tiny tube is threaded into the heart to open the vessel, a life-saving step that stops the damage in its tracks. Yet, surviving the event is only the beginning of a long recovery. For many patients, the weeks following the procedure are filled with a quiet struggle: the body, weakened by the trauma and the necessary bed rest, begins to lose its strength. Muscles grow stiff, breathing becomes shallower, and the simple act of walking to the bathroom can feel like a monumental effort. The heart, though repaired, often remains sluggish, and patients frequently find themselves unable to return to their normal lives or jobs. Doctors have long known that getting patients moving again is crucial, but the exact timing and method matter greatly. Too little movement risks complications from inactivity, while too much too soon can be dangerous. The question facing modern medicine is not just whether to move, but how to move the heart and lungs together most effectively during those critical first days in the hospital.

A team of researchers at the Sixth Affiliated Hospital of Guangxi Medical University set out to answer this question by testing a specific approach for patients who had just undergone the artery-opening procedure. They focused on what is called Phase I cardiac rehabilitation, which takes place while the patient is still in the hospital. The researchers wanted to see if adding a specific type of breathing exercise to the standard early movement routine would yield better results than movement alone. They recruited 110 patients who had recently suffered a heart attack and received the procedure. These individuals were randomly split into two groups. One group received the standard care of the hospital, which included medication and general advice. The other group, the experimental group, followed a structured, one-week program that combined gentle physical activity with specific breathing techniques. This program started on the very first day of recovery with simple movements like wiggling the toes while lying in bed, gradually progressing to sitting up, standing, and eventually walking short distances in the ward. Alongside these movements, the patients practiced abdominal breathing, where they learned to inhale deeply through the nose to expand the belly and exhale slowly through pursed lips, a technique designed to help the lungs work more efficiently.

The researchers tracked these patients closely, measuring their heart and lung performance before the intervention and again three months later. They used a specialized test where patients walked on a treadmill while wearing a mask that measured exactly how much oxygen they could use and how hard their heart had to work. They also looked at ultrasound images of the heart to see if its structure had changed. The results showed a clear difference between the two groups. After three months, the patients who had done the combined exercise and breathing training could use significantly more oxygen during exertion. Their bodies became more efficient at turning that oxygen into energy, and their hearts pumped more blood with each beat. Specifically, the group that trained saw their peak oxygen usage rise by about 2.4 units, their ability to sustain effort without tiring increase by 1.5 units, and the amount of blood pumped per heartbeat grow by more than one unit. In contrast, the group that received only standard care showed much smaller improvements in these key areas. The training did not just help them breathe better; it made their entire cardiovascular system more resilient.

Importantly, the study found that this early, active approach was safe. None of the patients in the training group suffered a new heart attack, a dangerous irregular heartbeat, or any other serious complication because of the exercises. The researchers also looked to see if the heart itself had physically changed shape or grown stronger in terms of its pumping power, measured by the ejection fraction. Surprisingly, they found no significant difference in these structural measurements between the two groups after three months. This suggests that while the training dramatically improved how the body uses oxygen and how the patient feels in terms of stamina, it did not necessarily reverse the physical remodeling of the heart muscle in such a short time. The heart's structure may simply require a longer period of rehabilitation to show visible changes on an ultrasound.

The study concludes that combining gentle movement with focused breathing exercises during the first week after a heart attack procedure offers a tangible benefit. It helps patients regain their breathing capacity and physical endurance faster than standard care alone, without increasing the risk of harm. While the heart's physical structure may take longer to heal, the ability to move and breathe efficiently improves quickly, giving patients a stronger foundation for their long-term recovery. The researchers note that their work was done in a single hospital with a relatively small number of people, so larger studies are needed to confirm these findings across different populations. However, the evidence suggests that for a patient recovering from a heart attack, the simple act of learning to breathe deeply and move gently while still in the hospital bed can be a powerful step toward reclaiming a full life.