News

Physical activity is essential for maintaining optimal overall health and exercising regularly is known to reduce the risk for heart disease, diabetes, depression, some cancers, and numerous other health–related issues. Yet despite this, it’s estimated that over three million people worldwide die prematurely each year because they are not getting enough physical activity.

One important factor that contributes to this issue is that many individuals spend a large portion of their days sitting, which is called a sedentary lifestyle. Following a sedentary lifestyle and sitting for too much time each day is now recognized as a dangerous habit that can lead to a variety of health problems, including obesity, heart disease, diabetes, and cancer. Evidence even suggests that individuals who are physically active and meet the recommended guidelines for activity are still at risk for certain health complications if they spend too much time sitting.

Physical activity guidelines typically make general recommendations for individuals to reduce their sedentary time, but they have not yet provided specific guidance on how often and how long sedentary time should be interrupted. With this in mind, a study was conducted to investigate whether taking occasional breaks from sitting had an effect on heart– and metabolism–related risk factors, and if so, how these effects changed with varying frequencies and durations.

Researchers selected 11 middle– and older–aged adults to participate in the study and instructed them to complete each of the following 8–hour conditions on 5 separate days:

• One uninterrupted sedentary condition (control intervention)


• Four acute trials that involved different frequency/duration combinations of sedentary breaks, which involved light–intensity walking (experimental intervention):
  
  
  • Sedentary breaks every 30 minutes for 1 minute each
  
  
  • Sedentary breaks every 30 minutes for 5 minutes each
  
  
  • Sedentary breaks every 60 minutes for 1 minute each
  
  
  • Sedentary breaks every 60 minutes for 5 minutes each
  
  

After each patient completed one intervention, they switched and completed the other intervention. Glucose levels were measured every 15 minutes and systolic blood pressure was measured every 60 minutes during these interventions.

Results showed that all intervals of sedentary breaks led to significant decreases in systolic blood pressure. The largest reductions in systolic blood pressure occurred in the group that took sedentary breaks every 60 minutes for 1 minute and every 30 minutes for 5 minutes. Similarly, glucose measurements also decreased after sedentary breaks, but the only significant reduction occurred when participants took breaks every 30 minutes for 5 minutes.

This study shows that taking sedentary breaks for different intervals is effective for reducing systolic blood pressure and glucose levels. Higher frequency and longer duration breaks (every 30 minutes for 5 minutes) appears to be most effective for targeting glycemic response, while shorter breaks may be sufficient for lowering blood pressure.

Therefore, if you currently spend most time of the day sitting, it appears that simply getting up for short, light–intensity walking breaks could counteract some of the negative effects of sedentary behavior by improving your glycemic control and blood pressure. But there’s a rule of thumb that also applies here: some is better than none, and more is better than less. So if you’re interested in becoming more physically active but feel that you can use a boost, a physical therapist can help you get there by designing a personalized exercise program based on your body type, abilities, and goals.