Exercise Can Help an Aging Heart No Matter How Old You Are

Despite temperatures in the teens, a jogger runs along Lake Michigan on January 3, 2018 in Chicago, Illinois. Getty Images

Aging can cause a stiffening in the heart, hindering its ability to pump out blood. But new research finds that there is a sweet spot at late middle age, when getting off the couch and committing to exercise four to five days a week can make a critical difference.

"This 'dose' of exercise has become my prescription for life," said Dr. Benjamin Levine, Director of the Institute and Professor of Internal Medicine at UT Southwestern, in a press release. "I think people should be able to do this as part of their personal hygiene—just like brushing your teeth and taking a shower."

Granted, doing an interval workout may require more effort than taking a shower. But the researchers' findings, published Monday in the journal Circulation, suggest that making the time and having the discipline to incorporate aerobic exercise into a daily routine four to five times a week can, after two years, reverse or reduce the risk of heart failure caused by decades of a sedentary lifestyle.

To test the potential benefit of introducing regular exercise on heart health, the researchers analyzed the hearts of 53 adults, aged 45 to 64. None of the participants had engaged in regular exercise throughout their lives, but all were otherwise healthy. The men and women were then divided into two groups. Half introduced a routine four to five days a week of regular, supervised cardiovascular exercise, while the other group began doing yoga and balance training for the same number of days. After two years, the participants' hearts were analyzed again to look for signs of any improvement.

Among the adults who had focused on yoga and balance training, the researchers saw no signs of improvement in the heart. But there was a clear 18-percent improvement in the maximum oxygen intake among those in the cardiovascular program, as well as a 25-percent improvement in elasticity in the left ventricular muscle of the heart.

Elasticity may be not be something most people associate with a healthy heart, but as Levine explained, it's a key factor. The heart's left ventricle is the chamber that pumps oxygen-enriched blood back out into the body. A sedentary lifestyle, Levine says, can cause the heart's muscle here to stiffen, which can lead to the heart chamber not filling as well with blood. That can lead to a higher risk of heart failure later in life.

Earlier research by UT Southwestern cardiologists revealed how the left ventricular muscle can begin to stiffen in middle age among people who did not include exercise in their regular routines.

"Imagine yourself taking a fresh, brand-new rubber band out of a box. When you stretch it, you feel the elasticity. You let go and it snaps back," Levine told Newsweek. "Then put that rubber band in your junk drawer and what happens. When you take it out years later, it doesn't really stetch and doesn't snap back. In the same way, elasticity is one of the cardinal signs of youthfulness of the body."

Levine pointed out that loss of elasticity in the eyeballs is what causes people in middle age to start requiring bifocals and loss of elasticity in the skin leads to wrinkles. It's also what causes muscles in the joints and heart to slacken.

The cardiovascular workout introduced into the study group that saw improvements in heart function involved 30-minute sessions, plus warmups and cool-downs. One of the weekly sessions was a high-intensity workout in which the heart rate topped 95 percent of its peak rate for 4 minutes. One to two of the other sessions were longer but of more moderate intensity. And one to two sessions focused on strength training.

There were some limitations to the study. The participants were not diverse—most were white—so it's unclear that there may be differences in findings among other racial groups. It was also relatively small study and all the participants were willing and able to exercise. That's not always a given considering motivation can be a challenge, as can physical injuries or other limitations.

It's hardly revelatory that introducing exercise can improve long-term health. Previous studies have shown a clear link between exercise and multiple benefits, including cognitive function, cellular health and reduce rates of cancer. But what was surprising to Levine was how quickly heart health can be revived, even later in life, with the introduction of exercise.

"If the goal is to preserve youthful arteries and heart function," Levine said, "then exercise four to five days a week is what it takes."