Exercise Offsets Muscle Breakdown in Heart Patients

Exercise can curb muscle breakdown in heart failure patients (Photo: National Institutes of Health)

We all know physical activity is good for us, and now new research suggests regular exercise can also help the aging and those suffering from heart failure.

In fact, researchers say, maintaining a regular physical workout can offset the breakdown of muscle, increase strength, reduce inflammation and condition the body to handle even more exercise.

And, the good news is, it doesn’t matter how old the patient is.

“Many physicians – and insurance companies – still believe that cardiac rehabilitation does not really help in old age. This study clearly falsifies this belief,” said Stephan Gielen, M.D., the study’s lead co-author and deputy director of Cardiology at the University Hospital, Martin-Luther-University of Halle, Germany.

Heart failure, a potentially deadly condition, occurs when the heart can’t keep up with its workload.  If the heart muscle cannot pump enough blood, it cannot meet the body’s needs for blood and oxygen.

As a result, those with heart-failure get tired easily and can have shortness of breath.  Activities most of us take for granted, such as walking, climbing stairs or other actions that require even mild exertion, can become very difficult for those with this condition.

According to the American Heart Association, about 5,700,000 Americans age 20 and older have heart failure.

For their study,  researchers recruited 60 heart-failure patients and 60 healthy volunteers in 2005 and 2008.   Half of each of these two groups consisted of people 55 years and younger, while the other half was 65 years and older, allowing for an average age difference of 20 years between the groups.

Even a casual walk can fatigue someone with heart failure (Photo: Michael Cohen via Flickr/Creative Commons)

Half of the people in each age group were assigned, at random, to four weeks of supervised aerobic training, while the other half was told not to exercise during that time.

Before each group began their assigned schedule of exercises, or non-exercise, the researchers took biopsies from the thigh muscles of all the study subjects.  The muscle samples were taken again after the four-week test period.

Those assigned to the exercise group had four 20-minute periods of aerobic exercise every day for five days a week and also participated in one weekly 60-minute group exercise session.

The leg muscle strength of those in the exercise group was measured before they began their exercise program and once it concluded four weeks later.

The researchers found that all who exercised had increased their muscle force endurance and oxygen uptake – a measure of how much oxygen a body is consuming at any given time.  The heart failure patients 55 and under had increased their peak oxygen uptake by 25 percent, while those 65 and over increased it by 27 percent.  Both the younger and older groups of heart failure patients showed increased muscle strength after the four-week exercise program, but their muscle size was unaffected.

“Exercise switches off the muscle-wasting pathways and switches on pathways involved in muscle growth, counteracting muscle loss and exercise intolerance in heart failure patients,” Gielen said.

The study authors believe their research could lead to possible treatment of the muscle breakdown and wasting associated with heart failure.

Dr. Gielen joins us with more insight on this week’s radio edition of “Science World.”  See right column for scheduled times, or check out the interview with Dr. Gielen below.

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