Improving heart and lung capacity from adolescence onwards, over a prolonged period of time, can help protect us from cardiovascular disease later in life, says an American study published in JAMA Internal Medicine.

Health professionals have known for a long time that sport, when practiced throughout life, acts as a defense against cardiovascular disease. Getting fit, even in adulthood, as far as it is physically possible, helps to prevent heart disease.

The good news revealed by this study which was undertaken by researchers in the US at the Johns Hopkins Medical School, Beth Israel Deaconess Medical Center, and the University of Michigan, is that the more our heart is made to work early in life, on a regular basis, while increasing session times and effort, the more the risk of developing heart problems is reduced.

Over a period of 27 years, the scientists monitored 4,872 young adults aged between 18 and 30, who underwent treadmill exercise testing in the form of two-minute running sessions of increasing difficulty to work their heart and lung capacity.

Their findings showed that each additional minute of exercise was linked to a 15 percent lower risk of dying and a 12 percent lower risk of cardiovascular disease. In other words, increasing the length of an exercise session is good for our heart.

Treadmill exercise tests carried out seven years after the first tests on 50 percent of the starting panel, revealed that a one-minute reduction in fitness was linked to a 21 percent increased risk of death and a 20 percent increased risk of heart-related death.

During the study follow-up, the participants were assessed for obesity, left ventricular heart mass, the strength of heart muscle contraction, coronary artery calcification and cardiovascular events. Over that time, 5.6 percent of the participants died, including 73 percent from non-cardiovascular causes, 4 percent suffered cardiovascular events, 28 percent had coronary artery calcium by year 25 of the follow-up, and 11percent had left ventricular hypertrophy.

More generally, physical activity, when adapted to a patient's pathology, physical capacity and medical risk, is a recognized and scientifically proven drug-free therapy, which works as an addition to conventional treatments.