Exercise Fitness Accurately Predicts Death

exercise fitness accurately predicts death

Exercise fitness accurately predicts death


New study analyzing 58,000 adults undergoing heart stress tests finds that exercise fitness accurately predicts death over a 10-year period.

The phrase “exercise is good for you” should come as no surprise. Numerous studies, some reported here, have found that exercise lowers the risk of diseases and prolongs life. But can physical fitness be a powerful predictor of how long you’ll live?

A new study from Johns Hopkins Medicine finds that exercise fitness accurately predicts death, at least in people undergoing a treadmill test.

Exercise Fitness Accurately Predicts Death over 10 Years

The study was published in Mayo Clinic Proceedings.

Today cardiologists use several different scoring system to evaluate heart patients risk of dying. The existing scoring systems include EKG data and other factors to predict who is at a greater risk of dying.

The new analysis put forth in this study differs by being able to predict risk of dying over a 10-year period by only determining fitness level of patients using a simple formula.

“The notion that being in good physical shape portends lower death risk is by no means new, but we wanted to quantify that risk precisely by age, gender and fitness level, and do so with an elegantly simple equation that requires no additional fancy testing beyond the standard stress test,” says lead investigator Haitham Ahmed, M.D

Which parameters was used to assess risk?

The parameters researchers took into account was age, gender, peak heart rate during exercise and the ability to tolerate physical exertion. The physical exertion is measure by so-called METs, a gauge of how much energy the body exerts during exercise. Walking slowly would score as two METs while running would score as 8 METs. The full scientific formula researchers developed from the data was:

percentage of maximum predicted heart rate + 12(metabolic equivalents of task) – 4(age) + 43 if female.

This formula was the result of data collected from 58,020 people between 18 and 96 years old from Detroit, Michigan who underwent standard exercise stress tests between 1991 and 2009. All people participating performed a treadmill test because of chest pain, shortness of breath, fainting or dizziness but didn’t have an established diagnosis of heart disease. Following the treadmill test researchers tracked the number of deaths in each fitness bracket over a 10-year period.

Researchers found that the fitness level of participants was the most powerful predictor of death or survival in people at roughly the same age and same gender. Even after accounting for blood pressure, heart rate and diabetes, exercise fitness level remained the strongest predictor of death.

The scores in the test ranged from -200 to 200 with lower scores equaling a greater risk of death. Patients who scored high in the test between 0-200 only had between a 2-3% risk of dying while people between -100 and -200 had worrisome 38% risk of dying over the next 10 years.

If confirmed that exercise fitness is a powerful predictor of death means that hospitals can quickly, and without having to use expensive equipment, determine a patient’s risk of death. Finding people at high risk also means interventions can be implemented avoiding unnecessary deaths.

Image Credit: Julieanne via flickr.com, CC BY-NC-ND 2.0