Learn how much exercise you need to prevent death

London: Norwegian researchers have developed a novel activity tracker that uses heart rate data to customise the amount of exercise one needs to reduce the risk of death from cardiovascular disease.

Heart rate is the single-most accurate reflection of the body's response to activity.

The study described the science behind Personal Activity Intelligence (PAI), the first activity tracking score that uses heart rate to help people achieve optimal health.

"The health benefits of regular exercise are well established but individuals do not know how much they need to prevent cardiovascular disease and premature death," said lead author Dr Javaid Nauman, researcher at Norwegian University of Science and Technology in Trondheim.

"People may be insufficiently active because they do not have personalised, meaningful information about how much physical activity they require, and at what intensity," Dr Nauman noted.

PAI translates heart rate data from any physical activity (walking, swimming, dancing, cycling) and personal information (age, gender, resting and maximum heart rate) into one simple score.

"The goal is to keep your PAI score above 100 over a seven-day rolling window to protect yourself from premature death related to heart disease," said Dr Nauman.

To develop PAI, the researchers used data on 4,637 individuals from the HUNT Fitness Study and derived an algorithm.

Men and women with a PAI level above 100 had 17 per cent and 23 per cent reduced risk of cardiovascular disease mortality among men and women compared to the inactive group.

The corresponding risk reduction for all-cause mortality was 13 per cent and 17 per cent for men and women, respectively.

"The more elevated your heart rate is during exercise, the more quickly you accumulate PAI points, but you can also work out at lower intensities for longer duration to earn PAI," the authors noted.

"Our research shows that keeping your PAI score at 100 or above could prevent premature death," Dr Nauman said.

The science behind the tracker was presented at 'ESC Congress 2016' in Rome, Italy on Saturday.