Sitting for longer than 25 minutes may be a tipping point for worse health outcomes, world-first Swinburne research finds

It’s widely accepted that sitting around for a long time is bad for us – but world-first Swinburne research has revealed that the magic number for moving may be shorter than you think.  

Swinburne’s Dr Christian Brakenridge is an expert in 24-hour behaviours like sitting, standing and sleeping, and lead author of the study.  

Using specialised shorts with conductive fabric sensors that monitor muscle electrical activity (EMG), his team measured participants daily lives, across more than 7,000 sitting periods. 

They found more than 25 minutes of sitting without interruption leads to lower levels of muscle activity, which in turn may lead to poor health outcomes.  

“Our research found that we use our muscles less when sitting for a prolonged time than if sitting for a shorter time,” says Dr Brakenridge. 

“But, we found that breaking up sitting with exercise or walking means our muscles are more active during sitting.”  

Dr Brakenridge says less muscle activity may coincide with decreased blood flow and lower uptake of blood sugars. This can contribute to heart disease and type 2 diabetes risk. 

The good news is that how you sit can have a positive impact. 

More ‘active’ types of sitting, potentially like driving a car, talking to friends or working at a desk may include tiny muscle movements, and are consequently not as likely to be as detrimental to our health as sitting down to watch a movie for a couple of hours.  

“Even small movements during sitting have been linked to better health outcomes, like lower BMI, waist circumference and cardiovascular disease risk.” 

Dr Brakenridge says the research demonstrates breaking up sitting is a simple way to counteract the impacts of too much sitting. 

“Consider a total daily sitting duration of 10 hours,” he explains.  

“Breaking this up with an activity every 25 minutes could result in approximately 1.5 hours of increased muscle activity during sitting time. This would correspond to a 10 per cent reduction of muscle inactivity during waking hours, which our previous research has shown is associated with better health outcomes.” 

“As we increasingly spend time at screens, particularly when working a sedentary job, it’s more important than ever to schedule movement to break up sitting.  

“Tiny changes like having a small glass of water to get up to refill often can make a drastic impact on your daily routine.”