An inspiring new study from scientists at UT Southwestern suggests the damage caused to a person's heart from years of sedentary behavior can be successfully reversed by the right "dose" of exercise. The two-year study found that exercising four to five times per week can significantly improve a person's heart elasticity, as long as the training begins before the age of 65.

The latest study follows on from earlier research illustrating how a sedentary lifestyle can stiffen the ventricular muscles in the heart. Senior author on the new study Benjamin Levine explains, "When the muscle stiffens, you get high pressure and the heart chamber doesn't fill as well with blood. In its most severe form, blood can back up into the lungs. That's when heart failure develops."

The new research examined whether this aging-related heart damage could be reversed by exercise. The experiment followed over 50 subjects aged between 45 and 64 for two years, with one half receiving an intense, and directed, exercise regime and the other half acting as a control group undertaking yoga and balance training.

The exercise group ultimately demonstrated notable success in regaining a degree of heart elasticity after two years of training, with a more than 25 percent improvement in ventricular muscle elasticity and an 18 percent improvement in maximum oxygen intake compared to the control.

Previous work by the UT Southwestern team has revealed that in order to reap these heart-improving benefits the exercise needs to be performed four or five times per week. An earlier study suggested that exercising only two to three times per week was not enough to achieve the full beneficial effects. It was also noted that these cardiac improvements were not seen in subjects who commenced exercising after the age of 65, suggesting the window for exercise-related heart elasticity was between 45 and 64.

The ideal exercise regime considered by the researchers involves four to five sessions per week, consisting of one high-intensity aerobic session, one or two strength training sessions, and one or two moderately intense sessions involving the subject only becoming a "little short of breath."

"Based on a series of studies performed by our team over the past five years, this 'dose' of exercise has become my prescription for life," says Levine. "I think people should be able to do this as part of their personal hygiene – just like brushing your teeth and taking a shower."

The latest study was published in the journal Circulation.