A major Australian study has found that regular movement, even unstructured play or casual activity, can significantly reduce symptoms of depression and anxiety in children and teenagers.

Researchers at the University of South Australia reviewed 375 clinical trials involving more than 38,000 young people aged between five and 18.

Their findings show that physical activity has a powerful impact on mental health, and the benefits can appear within weeks.

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“We found that when children and teenagers moved more, through play, sport or exercise, it significantly reduced depression and anxiety,” said lead researcher Dr Ben Singh, a research fellow at UniSA.

The research comes amid growing concern about youth mental health, with one in four Australian children now experiencing symptoms of depression or anxiety, often from a young age.

Singh said pressures from school, uncertainty about the future, and constant exposure to social media were major contributors.

He believes movement is a low-cost, accessible tool that can help families, schools and policymakers respond.

“A lot of children either don’t receive treatment or don’t respond well to traditional methods like therapy or medication,” he said.

“Movement gives us a practical alternative.”

The study found the greatest mental health improvements occurred in programs lasting fewer than 12 weeks, meaning children don’t need to wait months to see results.

Importantly, the activity didn’t need to be intense or structured. Informal movement, such as walking, riding a bike or playing a game outside, delivered similar mental health benefits to team sports or exercise classes.

“It doesn’t have to be elite sport,” Singh said.

“A game of backyard cricket or a bike ride with friends is enough. What matters most is that kids are active.”

Beyond physical benefits, movement was shown to boost confidence, improve energy levels and support social interaction, particularly when done with peers.

“Children who move more tend to feel better, connect more and build confidence,” Singh said.

“It’s something every parent and teacher can encourage.”

The research team is now calling on schools, communities and health professionals to treat physical movement as a key part of mental health care.

“Movement should be part of the conversation when we talk about supporting young people,” Singh said.

“It’s free, it’s effective and it could make a lasting difference.”