Updated

Adults with type 2 diabetes should be getting aerobic exercise on most days of the week, as well as some weight training, to help protect their heart health, according to guidelines published Monday.

In a new scientific statement, the American Heart Association (AHA) calls on people with diabetes to get at least 2.5 hours of moderate aerobic exercise, such as brisk walking, each week — or at least 1.5 hours of vigorous activity, such as jogging.

On top of that, they should do some form of resistance training three times per week — working on all major muscle groups of the body.

The statement, published in the AHA journal Circulation, takes aim at the "unprecedented epidemic" of type 2 diabetes, which now affects about 23 million U.S. adults.

Type 2 diabetes is closely related to obesity, and the disease can often be managed by diet, exercise and weight loss. Because it is also a major risk factor for heart disease, preventing or better managing diabetes could prevent many cases of heart disease as well.

"Given the observed increases in type 2 diabetes in adults over the last few decades in developed countries, and the increasing numbers of overweight and obese individuals throughout the world, we must look at ways to reduce the cardiovascular complications of diabetes, and exercise is one of those ways," Dr. Thomas H. Marwick, chairman of the writing group that devised the guidelines, said in a written statement.

Most people with diabetes can safely exercise at a moderate intensity, according to the AHA. Those who are sedentary should start slowly, gradually building up the amount of the time they exercise each day, Marwick told Reuters Health.

Beginners can even break their daily exercise time into smaller doses, noted Marwick, a professor of medicine at the University of Queensland in Brisbane, Australia. They could, for instance, perform three 10-minute bouts instead of 30 minutes straight.

The AHA also recommends that people spread their exercise time out across the week, with no more than two consecutive days of inactivity.

For people who lack the motivation to get moving, exercising with a group might help, Marwick said. It need not be a formal class, he noted; walking with a few friends, for example, can provide the "peer pressure" many people need to stick with an exercise routine.

Marwick also advised people to choose a form of exercise they enjoy and can keep up.

"For most people walking is fine, and no fancy equipment is needed,"

he said. He added, however, that the walk should be brisk, not a "dawdle."

Moderate intensity means exercising at 55 percent to 69 percent of one's maximum heart rate, which is calculated by subtracting the person's age from 220. For people older than 50, Marwick noted, that would translate to a heart rate of around 100 beats per minute.

An inexpensive heart rate monitor can help people keep their workout intensity in the right range, he added.