Exercise: Spread It Out Or All At Once?

Metabolic syndrome odds decrease with moderate exercise no matter how time is divvied up

(RxWiki News) Many Americans may find it hard to fit exercise time into their busy schedules. But if they can free up just a few hours each week, they may get all the exercise they need to avoid some serious health problems.

Both the World Health Organization (WHO) and American Heart Association recommend that adults do at least 150 minutes of moderate-intensity physical activity each week. That activity is meant to be spread out throughout the week.

But according to a new study, heart-pumping activity may not need to be spread out. 

This study suggested that doing 150 minutes of moderate-intensity exercise all at once may reduce the risk of metabolic syndrome just as well as doing that exercise over the course of a week.

The researchers said that these findings show that it may not matter how adults split up their physical activity time to effectively reduce their risk for metabolic syndrome.

"If spreading out exercise doesn't work, do it all at once."

This study led by Janine Clarke, PhD, from the School of Kinesiology and Health Studies at Queen's University in Ontario, Canada, looked at the links between metabolic syndrome and how often physical activity is performed throughout the week among physically active adults.

Metabolic syndrome is a group of factors, including high blood pressure, cholesterol and a large waistline, that increases the risk for stroke, diabetes and heart disease.

The researchers surveyed data from 2,324 adults involved in the Canadian Health Measures Survey between 2007 and 2011. 

Participants were about 41 years of age on average, and a little less than half were men.

The researchers tracked the number of participants who did more than 150 minutes of moderate physical activity each week. Those who met the recommended activity requirements were categorized into one of two groups. 

The first group was categorized as frequently active. They were told to continue doing 30 minutes of moderate intensity activity for five or more days a week.

The second group was classified as the frequently inactive group. They were instructed to do 30 minutes of moderate activity no more than four days a week.

The researchers measured participants’ level of physical activity over a seven-day period by having participants wear an accelerometer to track all their movements.

Participants' age, gender and education level also were taken into account.

This study's results showed that the infrequently active group was almost twice as likely as the frequently active group of having metabolic syndrome, but the researchers said the difference was not significant.

After adjusting for total physical activity throughout the whole week, the odds were reduced.

"The findings indicate that it does not matter how adults choose to accumulate their 150 weekly minutes of physical activity," said Ian Janssen, PhD, co-author of the study and CRC Chair in Physical Activity and Obesity at Queen's University, in a press release.

"For instance, someone who did not perform any physical activity on Monday to Friday but was active for 150 minutes over the weekend would obtain the same health benefits from their activity as someone who accumulated 150 minutes of activity over the week by doing 20-25 minutes of activity on a daily basis," Dr. Janssen said.

Jim Crowell, head trainer and owner of Integrated Fitness and dailyRx Contributing Expert, said that working out for results is different depending on who takes the time to think about their health.

"Certain people's bodies react differently to different workout regimens so I try to break people into more specific desires and training plans that should work well for them individually," he said. "Depending on somebody's diet and stress levels, their workout regimen may work with one day per week or five days per week."

The researchers also found that the odds of having metabolic syndrome was almost four and a half times higher among the physically inactive participants compared to the active ones.

These researchers noted that they did not find why metabolic syndrome decreased among those who exercised more often.

Future research can look into what patterns of physical activity can more adequately assess the possible benefits of regular activity, according to the researchers.

The study, supported by the Heart and Stroke Foundation of Ontario, was published online June 20 in the journal Applied Physiology, Nutrition and Metabolism.

No conflicts of interest were declared.

Review Date: 
June 22, 2013