A veteran PE teacher says school curriculum demands are taking their toll on physical education.

New research by Otago University suggests schools should commit two and a half hours to PE every week, to ensure young people get enough exercise.

Spotswood College's Phil Gayton is backing the idea, saying it would help make exercise habitual.

Gayton told Mike Hosking he's been a PE teacher for more than four decades, and remembers a time when two hours a week was mandatory for all students.

"The mandate part of it has also gone, so some school have basically no physical education at all."

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