The study is the first to examine the impact of swapping time spent on activities like sitting, standing, sleeping or walking on mortality.
It shows that swapping even one hour of daily sitting with standing is linked to a five per cent reduction in the risk of premature death.
"Previous research established the benefits of adequate physical activity or sleep and the risks of too much sitting, but this is the first to look at what happens when we replace one activity with an equal amount of another," said lead author Emmanuel Stamatakis, an associate professor at the University of Sydney.
"With the average person sitting watching two to three hours of TV a day, there is definitely scope for people to get off the couch and be more active," said Stamatakis.
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"But it's also time for governments to realise that physical activity cannot be treated as the sole responsibility of individuals because we live in a physical activity-hostile world," said Stamatakis.
The study used statistical modelling of health-related data from the over 200,000 randomly sampled middle-aged and older people from New South Wales who took part in the 45 and Up Study over a four year period.
However, risk of an early death was increased by between 13 and 17 per cent when one hour of daily walking or exercise was substituted with equal amounts of sitting or any other sedentary activity.
"The important thing for people to remember is the more you move the better, even if this movement is incidental or at a light intensity," said Stamatakis.
"It doesn't have to be formal exercise in a gym, it can be as simple as kicking a ball with your kids in the backyard, going for a walk in the neighbourhood instead of watching another hour of TV, or walking your dog for an extra half an hour a day," said Stamatakis.