Teenager Sam Ruthe has broken Sir John Walker's 1982 New Zealand mile record.

He clocked a time of 3:48.88, which is the fastest indoor mile ran by a high school student. 

He told Mike Hosking that consistency is key when it comes to running, and he's confident that he can get close to his record-breaking time again. 

'I try and always feel the same going to a race, I reckon if it was set out perfectly and it was the exact same race each time I'd probably get within...a second of that time again.'

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