The world's top athletes are starting younger and competing for longer.

New Zealand's Erika Fairweather made it through to yesterday's women's 400 metre freestyle final at just 17 years old, coming up against a 14-year-old Canadian.

And a 13-year-old has beaten a 16-year-old and another 13-year-old to women's skateboarding gold.

Sport and Exercise Science New Zealand chairman Nick Draper told Mike Hosking  we're seeing those younger athletes competing at the top level for longer.

“The sport science and the physiotherapy and the care that is taken with athletes, is probably helping to enhance their active playing lives.”

Fairweather is back in the water today in the women's 200 metre freestyle semi-finals this afternoon.

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