The study was conducted by a research team at Johns Hopkins Medicine who evaluated the physical activity over time of more than 11,000 adults in the U.S. They aimed to determine whether starting to exercise during middle age would decrease the risk of heart failure even though you have been sedentary most of your life; or whether the risk of heart failure increases if you stop being active in middle age, but have been active for much of your life.
In order to address those questions, the research team used data enrolled in the Atherosclerosis Risk in Communities (ARIC) study. The average age of the participants was 60; 57 percent were women; and most were either white or African-American.
For an average of 19 years, they tracked the participants yearly for cardiovascular disease events, including heart attack, stroke, and heart failure through telephone interviews, hospital records, and death certificates. They recorded 1,693 hospitalizations and 57 deaths due to heart failure over the course of the study.
At the first and third ARIC study visits, the participants also completed a questionnaire that asked them to assess their physical activity levels (“poor,” “intermediate,” or “recommended”) in line with guidelines issued by the American Heart Association. “Poor” pertains to no exercise at all; “intermediate” refers to one to 74 minutes weekly vigorous exercise; and the “recommended” amount is a minimum of 75 minutes each week of vigorous exercise, or a minimum of 150 minutes per week of moderate-intensity physical activity.
After the third visit, 42 percent of participants reported that they performed recommended levels of exercise; 23 percent revealed they performed intermediate levels; and 35 percent said they had poor exercise levels. From the first to the third visit (six years apart), 24 percent of participants increased their physical activity, 22 percent reduced it, and 54 percent remained in the same category.
Results showed that those who performed the recommended levels of exercise at both the first and third visits exhibited the greatest reduction in heart failure risk at 31 percent. Those who increased their physical activity from poor to intermediate or recommended had a 12-percent lower heart failure risk. In contrast, those who reduced their physical activity had an 18-percent increased heart failure risk.
The researchers also identified how much of an increase in exercise was needed to reduce heart failure risk. They calculated exercise as metabolic equivalents (METs), wherein one MET is equal to 1 kilocalorie per kilogram per hour.
They discovered that every 750 MET-minutes per week increase in exercise over six years decreased heart failure risk by 16 percent; and every 1,000 MET-minutes per week increase in exercise reduced heart failure risk by 21 percent.
Thus, the researchers concluded that an increase in physical activity level can reduce heart failure risk, while a decrease can increase the risk of the disorder. (Related: Exercise beats heart disease, even if started late in life.)
Heart failure is a serious condition in which the heart cannot supply the cells with sufficient blood. This can lead to fatigue, shortness of breath, and coughing. In addition, daily activities like walking, climbing stairs, or carrying groceries can become difficult too. Since usually there is no cure for it, it is important to take extra measures to prevent the disease.
Read more news stories and studies on heart disease prevention by going to HeartDisease.news.
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