Think you don't have enough time for a workout that will benefit your health? You may want to think again — a new study finds that running as little as 5 to 10 minutes a day may reduce the risk of death from heart disease.
Researchers analyzed information from more than 55,000 U.S. adults ages 18 to 100 in Texas, who were asked how much they ran over the past few months. About one-fourth of the participants were runners (they reported the duration, distance, frequency and speed of their runs), and the rest were nonrunners.
Over a 15-year period, runners were 45 percent less likely to die from heart disease, and 30 percent less likely to die from any cause, than nonrunners were, the study found.
When runners were divided into five groups based on the duration, distance and speed of their runs, all of the groups had a similar reduction in their risk of death from heart disease. For example, those who ran for less than 51 minutes per week (about 5 to 10 minutes a day) had a similar reduction in the risk of death as those who ran more than 176 minutes per week. [9 Healthy Habits You Can Do in 1 Minute (Or Less)]
The findings held even after the researchers took into account some factors that could affect a person's risk of death, such as age, smoking and drinking habits, or diagnosis of certain health conditions, such as high blood pressure.
"Because time is one of the strongest barriers to participate in physical activity, this study may motivate more people to start running and continue to run as an attainable health goal," said study researcher Duck-chul Lee, an assistant professor in the Iowa State University Kinesiology Department.
For healthy people, running may be a better exercise option than less-intense activities like walking, because running produces similar health benefits in terms of a reduced risk of death, in a shorter amount of time, Lee said.
"For younger individuals who are pressed for time, running is a far better option for time efficiency," Dr. Chi Pang Wen, of the Institute of Population Health Sciences in Taiwan, and colleagues, wrote in an editorial accompanying the study.
However, people who currently live very sedentary lifestyles may want to start out with walking before transitioning to running, to reduce the risk of injury, Lee said.
Lee said he was surprised that higher amounts of running did not confer a larger reduction in a person's risk of death. It's possible that higher amounts of running may have negative effects for some people, such as a risk of heart-rhythm problems or injury to muscles and bone, Lee said.
Still, some studies have found a link between running greater distances, such as more than 5 miles (8 km) a day and a decreased risk of heart problems, compared to running less than 2 miles (3.2 km) a day, so more studies are needed to determine if there is an optimum distance for running, the researchers said.
The study also found that runners lived three years longer, on average, than nonrunners. Those who took up running during the study period saw improvements in their risk of dying from heart disease, but those who ran throughout the study had the biggest benefits.
Lee said that once people start running, they "should increase their running time and speed appropriately as they become more fit." The Centers for Disease Control and Prevention recommends that people engage in at least 150 minutes of moderate aerobic activity, such as brisk walking, or 75 minutes of vigorous-intensity activity, such as running, per week.
The researchers noted that people in the study were asked to remember how much they ran over the last three months, which they may have not always recalled accurately. The study also did not take into account people's diet, which could have affected the results.
The study and editorial are published today (July 28) in the Journal of the American College of Cardiology.