Even the most dedicated gym-goers could be at risk for vascular events if they spend most of their day sitting down, according to a Reader’s Digest report.

According to a study presented at the American Heart Association’s Scientific Sessions, even individuals who stick to national exercise guidelines could still be in trouble if they live mostly sedentary lifestyles.

“You can be physically active and also have sedentary behavior,” study author Mary Cushman, MD, told Reader’s Digest. “They aren’t just opposites. People who are physically active don’t necessarily have low sedentary time.”

If a person remains sitting a large portion of their day—including office jobs or binge-watching TV—they’re more prone to developing blood clots in their legs, which can lead to venous thromboembolism, Cushman said. Clots can travel to the brain or lungs and cause life-threatening strokes.

“Keep moving to have a healthy lifestyle,” she said. “That involves not being sedentary, getting the recommended physical activity and eating a healthy diet, which will help prevent this disease as well as almost every other chronic disease. These are the key things about preventing disease and maintaining a healthy, long life.”

Read the full report here: