What's the best footwear to run in? Danny Rose investigates whether less is more.
While there's little doubt about the health benefits of running, the question of what we should wear on our feet is less clear-cut.
Online running forums are abuzz with the issue of going "barefoot" or as close as possible, while sports companies have responded with new lines of shoes stripped of the features they've spruiked for years.
(Nike's "Free" range of shoes, for example, promises a "more barefoot-like fit").
A new type of minimalist running shoe - barely more than padded gloves for the feet - called the Vibram Five Fingers has recently been seen on those grinding out laps on the nation's jogging tracks.
The changes have been sparked by growing concern that the generous cushioning offered by modern running shoes may encourage a style of running that isn't biomechanically natural, and could result in injuries.
Dr Craig Richards says humans throughout the ages ran mostly on the ball or mid-soles of their feet, and it was the invention of modern sport shoes that first allowed runners to hit the ground heel-first.
"You take shoes off people and they start landing on the outside of their forefoot - virtually no one lands on their heel when they are running unless they have got a cushioned shoe," says Richards, a senior lecturer at the University of Newcastle's School of Medicine and Public Health.
"There never has been any basis, theoretical or otherwise, to suggest that suddenly we should all start running on our heels."
Richards presented his concerns in a paper published in the British Journal of Sports Medicine last year.
But he's quick to add that it's no slam dunk for the "barefoot community" - there is an equal lack of research to support the use of minimalist shoes.
Instead, Richards says all shoe options should be seen as "experimental".
"In terms of the average recreational runner ... most would have no idea, I think, that what they are running in is experimental," he says.
"It may have been in use for 30 years, and cost a lot of money but it is just as experimental as the Vibram Five Fingers that someone might run past and ask 'What the hell are those?"'
Richards, who admits he runs in a minimalist shoe, says the debate is no longer confined to the hardcore fringes of the running community.
There is a "strong trend of small companies bringing out minimalist-style running shoes"; meanwhile "more and more people are taking up barefoot or minimalist-style running".
"But there is no clear evidence of the need for that," he says.
"And we are at risk of swinging from one untested paradigm to a second untested paradigm."
But Richards' paper hasn't gone down well with podiatrists.
Australasian Podiatry Council president and Sydney-based podiatrist Brenden Brown says there's plenty of anecdotal evidence supporting the use of different types of conventional running shoes.
For example, shoes with additional support are known to benefit those with pronating feet, or help prevent shin splints.
"Let's not throw out the baby with the bathwater ... if we can see anecdotally that this works then there is no need to in fact prove it," Brown says.
He also says many runners run "heel to toe" without injury, and much more research is needed before podiatrists would be recommending a shift away from conventional running shoes.
"We don't have a position on barefoot versus conventional running shoes ... you could say the jury is out,"he says. "I'm not prepared to say that barefoot running is bad but we don't want people throwing out their runners just yet."
Both are agreed on one thing. A decision to switch to a minimalist shoe shouldn't be taken lightly and any change should be introduced slowly to avoid placing extra demands on weaker muscles in the feet and legs and potentially leading to injury. FiveFingers NZ runs "natural running" workshops to help runners make the transition.
Richards also says the debate shouldn't discourage people from improving their overall health and fitness with a regular run. "Absolutely, running is a great exercise," he says. "It's bigger than any of the team sports, it is cheap, easy, and time efficient because you can do it as soon as you step out of your front door."