Even low-intensity activity shows benefits for health, study shows

A newly published study looking at activity trends and outcomes among American adults found that you don't need to kill yourself by running 10 miles a day to gain health benefits – you merely need to log more minutes of light physical activity than of sedentary behavior.

And the bar is pretty low for what constitutes light physical activity, researchers say. It can mean sauntering through a mall window-shopping instead of ordering online, fishing along a riverbank, or ballroom dancing.

In other words, casting a spinner or spinning on the dance floor can help offset our sedentary ways.

The problem, the authors say, is that nearly half of Americans surveyed did not engage in a sufficient amount of moderate-to-vigorous physical activity (more than 150 minutes a week) and, in fact, spent more time in sedentary mode than even doing light physical activity.

"That's actually rather frightening," said Bradley Cardinal, co-director of the Sport and Exercise Psychology Program at Oregon State University and co-author on the study. "About half of the people in this country are incredibly sedentary – basically, couch potatoes. And that can have some very negative effects on one's health."

Results of the study have been published online in the journal Preventive Medicine.

The study looked at the activity patterns of more than 5,500 adults through the National Health and Nutrition Examination Survey. Participants wore accelerometers recording movements that could be broken down by the minute, and the researchers found that 47.2 percent of Americans engaged in less than 150 minutes a week of moderate-to-vigorous physical activity and, perhaps more importantly, logged fewer minutes of light physical activity than of sedentary behavior.

They found that when the balance was on the positive side – adults spent more time moving than sitting – there was a strong association with favorable levels of triglycerides and insulin.

"It is preferable to get at least 30 minutes a day of moderate-to-vigorous physical activity in each day, but we now know that if you sit for the remainder of the day after getting this dose of exercise, you might not necessarily be escaping the risk of developing chronic disease," said Paul Loprinzi, a former doctoral student under Cardinal in OSU's College of Public Health and Human Sciences. Now an assistant professor at Bellarmine University, Loprinzi is lead author on the study.

"These findings demonstrate the importance of minimizing sedentary activities and replacing some of them with light-intensity activities, such as pacing back and forth when on the phone, standing at your desk periodically instead of sitting, and having walking meetings instead of sit-down meetings," he added.

Cardinal said results can vary with individuals, based on age, fitness levels, movement "pace" and other factors. In general, however, when even light activity minutes in a day surpass sedentary minutes, it can result in improved triglyceride and insulin levels.

"Someone just ambling along on a leisurely stroll may not get the same benefits as someone moving briskly – what we call a 'New York City walk,'" Cardinal said, "but it still is much better than lying on the couch watching TV. Even sitting in a rocking chair and rocking back-and-forth is better than lying down or just sitting passively.

"Think about all the small things you can do in a day and you'll realize how quickly they can add up," Cardinal pointed out.

Some of the ways Americans can get in some light physical activity without Olympic-style training:

• Go on a leisurely bicycle ride, at about 5-6 miles an hour;
• Use a Wii Fit program that requires a light effort, like yoga or balancing;
• Do some mild calisthenics or stretching;
• If you want to watch television, do it sitting on a physioball;
• Play a musical instrument;
• Work in the garden.

"Even everyday home activities like sweeping, dusting, vacuuming, doing dishes, watering the plants, or carrying out the trash have some benefits," Cardinal said.

"Remember, it's making sure you're moving more than you're sitting that's the key."