Why 30 minutes of exercise a day may not be enough

A lot of people who regularly exercise could still be at risk of the same health issues as those who don't.

New research suggests 30 minutes of daily exercise may not be enough to make a difference in people deemed "active couch potatoes".

The study out of Finland looked at 3700 subjects divided into three groups.

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They were people who exercised for 30 minutes a day, then were sedentary for the rest of the day.

Those who exercised for an hour a day and were sedentary for the remainder and those who exercised for 30 minutes of their day, but stayed active for e the rest of it.

Exercise scientist Amelia Phillips said those who were still sedentary for the rest of the day were what the study called "active couch potatoes".

"The sedentary behaviour counterbalanced the exercise," Phillips told Today Extra.

"The people that were lightly active with 30 minutes of exercise had much better body fat percentages, blood glucose and cholesterol levels."

Phillips said "lightly active behaviours" we do throughout the day made a big difference to our health, but vigorous exercise was also needed.

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"In Australia it is recommended to exercise for 2.5 to five hours a week," she said.

"The catch is you need to have vigorous activity on top of moderate which is one to two hours a week."

An example, according to Phillips would be going for a power walk, but breaking into a jog for 10 to 15 minutes somewhere in there too.

"That's where you couldn't hold a conversation, your perceived rate of exertion is eight out of 10 to 10 out of 10," she said.

While one to two hours of vigorous exercise a week is recommended, many of use either spend office hours sitting at a desk the whole time, or now work from home and miss out on the light exercise from getting into the office.

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Amelia said things like using a standing desk, choosing to take the stairs or even opting to have walking meetings instead of in a conference room are good ideas to get more light exercise in.

And for those who still need to find something vigorous to do - Phillips suggests getting a "BHAG".

"A 'big hairy audacious goal' - once a year, you're going to do a BHAG like a 50km trek with friends, or train for a 10km fun run," she said.

Watch the full segment above

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