John Arnold – The Conversation

Michael Dodge/AAP

December 25, 2025

Why do cricket balls have to be so hard?

John Arnold, University of South Australia and Tom Wycherley, University of South Australia

Cricket balls are incredibly hard and are the product of centuries of tradition and the extreme physical demands of the game.

Chimdessa Debele of Ethiopia poses with his shoe after coming third in the 2025 Berlin Marathon. CLEMENS BILAN/EPA

October 30, 2025

Running ‘super shoes’ may make you faster – but at what cost?

Joel Fuller, Macquarie University; Chloe Blacket, University of South Australia; Eoin Doyle, Macquarie University, and John Arnold, University of South Australia

Researchers are questioning whether the very features that are meant to boost performance may actually increase the risk of running-related injuries.

Slatan/Shutterstock

October 3, 2024

How do I know when it’s time to replace my running shoes?

John Arnold, University of South Australia and Joel Fuller, Macquarie University

The standard advice is to replace your runners after 500–800 kilometres. But science shows it could be more or less – here are the three signs to look out for.

Many runners opt for expensive footwear - but are they worth it? Fotografgruppen Fotografgruppen/flickr

September 4, 2015

Expensive running shoes don’t prevent injuries, but comfortable ones might

John Arnold, University of South Australia

Since avoiding injuries is a priority for runners, many end up buying expensive footwear for their purported safety features. But do the promises made by global footwear companies stack up?

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