When people recover from a heart attack, cardiac rehabilitation programs (supervised exercise and education) help their hearts heal. Researchers discovered that these rehabilitation programs change the levels of special proteins called myokines that your muscles release into your bloodstream. In this study, 110 heart attack patients who completed a 2-week rehabilitation program showed increases in certain myokines compared to patients who didn’t participate. These changes appeared to help with heart health and blood pressure control. The findings suggest that personalized rehabilitation programs based on the type of heart attack may be even more effective at helping patients recover.

The Quick Take

  • What they studied: Whether a 2-week heart attack recovery program changes the levels of special healing proteins that muscles release into the blood
  • Who participated: 220 people who had recently suffered a heart attack (110 completed rehabilitation, 110 did not). The study included both types of heart attacks: STEMI and NSTEMI
  • Key finding: Patients who completed the rehabilitation program showed increases in three important healing proteins (apelin, myostatin, and FSTL1), and these increases were linked to better heart function and blood pressure control
  • What it means for you: If you’ve had a heart attack, completing a cardiac rehabilitation program may trigger your body to produce more healing proteins that support heart recovery. This suggests rehabilitation is doing more than just making you stronger—it’s actually changing your body’s chemistry in beneficial ways. However, more research is needed to confirm these benefits apply to all patients

The Research Details

This was a randomized controlled trial, which is one of the most reliable types of medical studies. Researchers divided 220 heart attack patients into two groups: one group (110 people) completed a supervised 2-week cardiac rehabilitation program that included exercise, education, and monitoring. The other group (110 people) did not participate in the program and served as a comparison. Before and after the rehabilitation program, researchers measured blood pressure, heart rate, body composition, and levels of four special proteins called myokines in the patients’ blood.

Myokines are proteins that muscles release when they exercise. Think of them as chemical messengers that your muscles send out to help your body heal and function better. The researchers focused on four specific myokines: apelin, myostatin, follistatin, and FSTL1. They wanted to understand if the rehabilitation program changed these protein levels and whether those changes were connected to heart health improvements.

The study also looked at whether the type of heart attack mattered. There are two main types: STEMI (where a major artery is completely blocked) and NSTEMI (where an artery is partially blocked). The researchers examined whether these two groups responded differently to rehabilitation.

Understanding how rehabilitation programs work at the chemical level is important because it helps doctors explain why exercise is so beneficial for heart attack patients. If we know which proteins are involved in healing, we can potentially develop better rehabilitation programs tailored to individual patients. This research bridges the gap between what we observe (patients get healthier) and why it happens (specific proteins increase and improve heart function)

This study has several strengths: it used a randomized controlled design with a comparison group, included a reasonable number of participants (220 total), measured multiple relevant proteins, and was published in a reputable scientific journal (Scientific Reports). The study was registered in advance on ClinicalTrials.gov, which increases transparency. However, the rehabilitation program was only 2 weeks long, which is relatively short, and the study didn’t follow patients long-term to see if benefits lasted. The study also didn’t randomly assign patients to groups in the traditional sense, which is a limitation

What the Results Show

After completing the 2-week rehabilitation program, patients showed significant increases in three of the four myokines studied. Apelin levels increased substantially, myostatin levels increased, and FSTL1 levels increased. These increases were notably higher in the rehabilitation group compared to the non-rehabilitation group.

Interestingly, the fourth protein studied, follistatin, showed a different pattern. Follistatin remained higher in the non-rehabilitation group at both time points, suggesting that rehabilitation may work through different mechanisms than previously thought.

The researchers also discovered that the type of heart attack mattered. Patients with STEMI (complete blockage) showed increases in apelin and FSTL1 after rehabilitation, while patients with NSTEMI (partial blockage) showed increases in myostatin. This suggests that different types of heart attacks may trigger different healing responses to the same rehabilitation program.

Importantly, the increases in apelin and myostatin were not simply due to changes in traditional risk factors like cholesterol, blood sugar, or smoking status. This suggests these proteins have a special role in heart healing that goes beyond managing typical heart disease risk factors.

Additional findings showed that after rehabilitation, follistatin levels correlated inversely with diastolic blood pressure (the bottom number in a blood pressure reading), meaning higher follistatin was associated with lower diastolic pressure. FSTL1 levels were related to body fat, muscle mass, and overall body mass index, suggesting this protein may play a role in how the body changes its composition during recovery. These connections suggest that myokines influence multiple aspects of heart health and body composition

This research adds important new information to our understanding of how cardiac rehabilitation works. Previous studies showed that exercise helps heart attack patients recover, but the specific mechanisms weren’t clear. This study identifies myokines as key players in that recovery process. The finding that different types of heart attacks produce different myokine responses is novel and suggests that rehabilitation programs may need to be customized based on the type of heart attack a patient experienced

Several limitations should be considered: First, the rehabilitation program lasted only 2 weeks, which is relatively short, so we don’t know if these changes persist long-term. Second, the study didn’t follow patients after the program ended to see if the myokine changes led to better health outcomes over time. Third, the non-rehabilitation group was assessed only once, making it harder to determine if natural changes occurred over time. Fourth, the study didn’t include information about what the non-rehabilitation group was doing during those 2 weeks—they may have been exercising on their own. Finally, the study was conducted in a single location, so results may not apply to all populations

The Bottom Line

If you’ve had a heart attack, participating in a cardiac rehabilitation program is strongly recommended (high confidence). The evidence suggests these programs trigger beneficial changes in your body’s chemistry that support heart healing. The program should ideally be personalized based on your type of heart attack (STEMI vs. NSTEMI) for maximum benefit. Continue the exercise and healthy habits learned in rehabilitation beyond the initial 2-week program, as long-term benefits likely require ongoing effort (moderate to high confidence)

This research is most relevant for people who have recently experienced a heart attack and are considering or beginning cardiac rehabilitation. It’s also important for cardiologists and rehabilitation specialists who design these programs. Family members of heart attack patients should understand that rehabilitation is not just about getting stronger—it’s triggering important healing processes at the chemical level. People with other types of heart disease may also benefit, though this study specifically focused on acute coronary syndrome

The myokine changes observed in this study occurred within 2 weeks of starting rehabilitation. However, this doesn’t mean you’ll feel dramatically better in 2 weeks. Heart healing is a gradual process. Most cardiac rehabilitation programs last 8-12 weeks, and patients typically notice improvements in energy, exercise tolerance, and overall well-being over several weeks to months. The full benefits of rehabilitation may take 3-6 months or longer to fully appreciate

Want to Apply This Research?

  • Track weekly exercise minutes and intensity during cardiac rehabilitation, along with resting heart rate and blood pressure measurements. Record these metrics at the same time each day (morning is ideal) to monitor trends. Set a goal of completing the prescribed rehabilitation sessions and gradually increasing exercise duration as tolerated
  • Use the app to schedule and remind yourself of rehabilitation sessions, log completed workouts with duration and intensity, and track how you feel before and after exercise (energy level, shortness of breath, chest discomfort). This creates accountability and helps you see your progress, which is motivating. Share data with your rehabilitation team to ensure you’re progressing safely
  • After completing the initial rehabilitation program, continue tracking exercise and vital signs long-term. Monitor for any changes in symptoms, energy levels, or exercise tolerance. Set monthly check-ins to review trends and adjust your exercise routine as needed. This ongoing tracking helps maintain the beneficial changes triggered by rehabilitation and provides early warning if problems develop

This research describes how cardiac rehabilitation programs affect certain proteins in the blood of heart attack patients. While the findings are promising, this study does not prove that myokine changes directly cause better health outcomes. The study was conducted over only 2 weeks, so long-term benefits are not yet established. If you have had a heart attack or are considering cardiac rehabilitation, consult with your cardiologist or healthcare provider before starting any exercise program. This information is for educational purposes and should not replace professional medical advice. Individual results may vary based on your specific health situation, age, and other medical conditions