One thing we know for sure: Sitting for most of the day is terrible for your health, raising your risk for diabetes, obesity, high cholesterol and high blood pressure. But the remedy has been confusing. First, we thought that getting 30 minutes of cardio exercise every day was the answer because it benefits heart health and overall health. Then the “marching orders” were to get up from our desks every hour to stand, walk or stretch because incremental amounts of movement seemed to help undo the negative effects of sitting. There were even reports (widely misinterpreted) that sitting a lot wasn’t bad for you after all. (It is.) So, which is it? New research done at Maastricht University in the Netherlands may have found the definitive fitness prescription for people who, because of their jobs or another reason, sit a lot.
The study: The researchers wanted to identify the specific health effects of both cardio exercise and informal movement. To do this, they recruited 61 adults with different health profiles. About one-third were of normal weight and generally healthy, another third were overweight and the final third were overweight and had diabetes. The one thing that all participants had in common was that none exercised regularly.
Each participant was first tested for markers of heart and metabolic health, including cholesterol levels and insulin resistance, and then they completed three different four-day sessions, spaced 10 days apart to avoid skewing results, representing markedly different lifestyles…
- “Sit” sessions: Participants sat for 14 hours straight each day and got up only to use the bathroom.
- “Exercise” sessions: Participants sat for 13 hours and spent one hour pedaling a stationary bike each day.
- “Sit Less” sessions: Participants sat for eight to nine hours and spent seven to eight hours standing or casually walking around each day.
After each four-day session, the researchers repeated the health tests and compared the results to the original ones. Here’s what they found…
- “Sit” session: No surprise here—nonstop sitting does not do a body good. The participants showed increased insulin resistance and higher cholesterol levels. Blood tests also showed unfavorable changes to endothelial cells…those that line the inside of blood vessels. When these cells don’t work well, there is a greater risk for blood fats accumulating in the arteries and for arterial stiffness, two risk factors for high blood pressure and hardening of the arteries, precursors to cardiovascular disease.
- “Exercise” session: The endothelial health of the participants improved compared with where it was after the sit sessions, but cholesterol and insulin sensitivity didn’t budge.
- “Sit Less” session: The light but frequent physical activity of these sessions was associated with improved cholesterol and insulin sensitivity, but endothelial health did not budge.
What this means for you: The results show that exercise and light activities benefit your heart and metabolic health in different ways—and that you need to do both.
Exercise improves endothelial health by “training” blood vessels—increasing blood flow temporarily stresses them, and as a result, they become healthier, in much the same way that muscles become stronger and healthier from the stress of strength training. Exercise helps reduce blood pressure by increasing nitric oxide levels.
Light activity—standing, walking, stretching— improves what’s called insulin signaling. Your cells become more sensitive to insulin, and glucose is more easily cleared from the blood. It’s also possible that simply walking and standing throughout the day keeps insulin levels steady because the muscles you engage use blood glucose for fuel. Light activity might help improve cholesterol, in part due to an increase in an enzyme that boosts levels of HDL, the good cholesterol, and helps your body break down triglycerides (blood fats).
WAYS TO SIT LESS
More studies are needed to better pinpoint the ideal dose of light activities, but recent guidelines from countries including Australia and Belgium suggest that you get up every 30 minutes. But you can build that rather robotic regime into activities that more naturally match your lifestyle, for example…
- Hold walking meetings (get outside when the weather’s nice) and walk to colleagues’ desks instead of sending e-mails.
- Walk around the field during your child’s sports games and practices rather than sitting in the bleachers.
- When watching TV, do chores during the commercials.
- Drink more water—besides keeping you hydrated, you’ll have to get up to visit the bathroom more often (choose the farthest one you have access to).
- Set an alarm on your phone to remind you to move every half-hour.
Learn more about how to move more on the job and make your workspace more healthy and happy.