Sitting for too long is dangerous. Here's what'll help

How much do people need to walk to try and reverse the harmful health effects of prolonged sitting? According to researchers from Columbia University, it only takes five minutes of walking for every 30 minutes of sitting.

Most people know that they need to move more and sit less for their health. Researchers noted in their study, published in Medicine & Science in Sports & Exercise, that prolonged sitting time has been linked to chronic health problems. 

Even in teens, for example, sedentary behavior has been linked to a higher risk of depression. Also, sitting for a long time can even harm the health of people who do regular physical activity.

Yet it's not always easy to move more, especially on a busy workday. So for their new study, researchers looked at small sports tricks that people can perform daily. 

These included one minute of walking for every 30 minutes of sitting, one minute of walking for every 60 minutes of sitting, five minutes of walking every 30 minutes, five minutes of walking for every 60 minutes of sitting, and no walking at all.

The researchers stated that the study's purpose was to examine the acute effects of multiple breaks in sitting on cardiometabolic risk factors, while evaluating the effectiveness of varying the frequency and duration of breaks in sitting.

Each of the 11 middle-aged and older adults participated in the study for five days. Every day they sat for eight hours but engaged in one of the interventions as described above. Their glucose was checked every 15 minutes and blood pressure every 60 minutes, as these two figures are considered key indicators of cardiovascular health.

Of the exercise breaks, walking for five minutes every 30 minutes appeared to be the optimal intervention. Specifically, participants who walked this amount of time showed significant reductions in glucose accumulation. 

Although all the breaks led to reduced blood pressure compared to sitting all day, the greatest reductions were seen in five minutes of walking for every 30 minutes of sitting, and one minute of walking for every 60 minutes of sitting.

Researchers wrote that this study showed the effectiveness of small breaks in prolonged sitting. Higher frequency and longer duration (every 30 minutes for 5 minutes) lowers blood sugar, while lower doses of exercise may be enough to lower blood pressure.

Is mood also affected?

Researchers also periodically measured the participants' mood levels, fatigue and cognitive performance during the tests. They found that all walking regimens, with the exception of walking one minute every hour, led to a significant decrease in fatigue and significant improvements in mood. Yet none of the regimens provided cognitive benefits.

Now, the researchers are expanding their work with a wider range of participants and are currently testing 25 different amounts of walking time on health outcomes and testing a wider range of people. 

Current participants are in their 40s, 50s and 60s; most aren't diabetic or have high blood pressure. One researcher said that their findings show that even small amounts of walking during the workday can significantly lower the risk of heart disease and other chronic diseases.