A new study led by researchers at Mount Sinai has found that individuals who can complete treadmill-based cardiac stress tests have a significantly lower mortality risk—regardless of their underlying heart disease. The findings, published in Mayo Clinic Proceedings on February 19, emphasize the protective role of physical fitness and highlight the need for physicians to prioritize discussions about exercise with their patients.
According to the study, the ability to exercise during a stress test was a more powerful predictor of long-term survival than traditional clinical risk factors, including hypertension, diabetes, smoking, and other cardiac-related conditions.
“Our data show that assessing a person’s ability to exercise during cardiac stress testing and their exercise capacity provides a stronger distinction between high- and low-risk patients than any other clinical risk factors evaluated at the time of cardiac stress testing,” said lead author Alan Rozanski, MD, Professor of Medicine (Cardiology) at the Icahn School of Medicine at Mount Sinai.
Large-Scale Study Highlights Exercise Impact
The study analyzed 15,562 patients who underwent single-photon emission computed tomography (SPECT) myocardial perfusion imaging, a test that evaluates blood flow to the heart at rest and under stress. Patients were categorized into two groups: those who could perform a treadmill stress test and those who required pharmacological stress testing, in which medication is used to dilate the coronary arteries as an alternative method of detecting blockages.
Researchers followed patients for nearly seven years and found a striking contrast in mortality rates. Among patients who performed treadmill exercise, the annual mortality rate was less than one percent, even for those with significant coronary artery disease (CAD) risk factors and comorbidities. Conversely, those who underwent pharmacological stress testing had a significantly higher risk of death, with mortality increasing in correlation with a higher burden of CAD risk factors and associated conditions.
While the study is observational and does not establish a direct cause-and-effect relationship, Dr. Rozanski noted that the strong correlation underscores the protective role of physical fitness.
Encouraging Physical Activity in At-Risk Patients
The findings suggest that physicians should emphasize evaluating a patient’s exercise ability during cardiac stress testing. If a patient cannot complete an exercise-based test, further investigation into the underlying causes could provide valuable insights into their overall health risks.
Additionally, the study reinforces the importance of encouraging physical activity among patients, particularly those with limited exercise capacity. Dr. Rozanski emphasized that newer medical guidelines support the idea that even small amounts of physical activity can yield significant cardiovascular benefits.
“This information should prompt doctors to have more meaningful conversations with patients about the importance of staying active,” he said. “Short bursts of activity throughout the day can add significant cardio benefits. That’s an important message for physicians to convey to patients.”
Future Research and Clinical Applications
The study highlights the critical role of exercise in long-term health outcomes and underscores the need for continued research into the relationship between physical fitness and cardiovascular disease. Future studies may explore whether targeted exercise interventions could improve survival rates for at-risk individuals and how personalized fitness programs could be integrated into cardiac care plans.
For now, the message remains clear: maintaining physical activity, even in small amounts, could substantially impact heart health and overall longevity.
Reference: Alan Rozanski, Heidi Gransar, Robert J.H. Miller, Donghee Han, Sean W. Hayes, John D. Friedman, Louise Thomson, Carl J. Lavie, Daniel S. Berman. Comparative Predictors of Mortality Risk in Contemporary Patients Referred for Stress Myocardial Perfusion Imaging. Mayo Clinic Proceedings, 2025.
