Is the treadmill stress test still considered valuable?
Yes, but we’re learning more about how to interpret its results. We did a 20-year follow-up on people who had undergone cardiac stress tests and were impressed by two key factors. The first was that exercise capacity, or how long a person walks on the treadmill, is probably the best determinant of whether that person is going to have a heart attack or stroke over the next 20 years. The second stems from heart rate recovery—how much your heart rate drops in the two minutes after exercise. (In a healthy person, it should drop by about 50 beats per minute within two minutes.) It turns out that people with either below average capacity or below average recovery rates accounted for more than 90 percent of major cardiac events over the ensuing 20 years.
