Here’s a good reason to break up long spells of sitting with brief walks-it may help blunt rises in triglycerides (fats in the blood) after meals, suggests a recent study from New Zealand in the Journal of Clinical Lipidology.
Big rises in triglycerides after meals are associated with increased cardiovascular risk. In the study, 36 adults (ages 18 to 40, most at normal weight) who had primarily sedentary occupations went through four seven-hour scenarios:
- Continual sitting.
- Continual sitting followed by a 30-minute brisk walk.
- Sitting with two-minute walking breaks every 30 minutes.
- Sitting with two-minute breaks plus the 30-minute walk afterward.
The next day, after consuming a high-fat breakfast, they repeated the scenarios for five hours (but with no 30-minute walk). Blood samples were collected hourly to measure triglycerides, insulin, and other factors.
Compared to just prolonged sitting, taking walking breaks resulted in a 7 percent reduction in post-meal triglycerides. Combining the breaks and the 30-minute walk lowered them by 11 percent. Taking a 30-minute walk the first day, by itself, had no effect on subsequent triglyceride levels, though like the other two interventions it improved insulin response somewhat.
“Overall, regular activity breaks, physical activity, and especially the two combined have the potential to facilitate a more favorable metabolic environment, which if maintained over months or years may be enough to explain why individuals who regularly break up sedentary time have better cardiometabolic health outcomes,” the study concluded.