Why was Chris Froome wearing a nose ring at the Tour de France?

If you saw Chris Froome's post-race interview after stage 12 of the Tour de France, you might have been distracted by what looked like a yellow nose ring up the Team Sky rider's nostrils

With Team Sky noted for their 'marginal gains’ approach to racing, this nose furniture is just another small piece of the puzzle in the quest for a fourth Tour de France win.

The device is called The Turbine, and dilates the nostrils to increase airflow through the nose, allowing the wearer to breathe more efficiently. Creator Rhinomed claims that nasal airflow is increased by an average of 38 per cent while wearing it.

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This apparently means that the device reduces the user's feeling of breathlessness and helping to expel CO2 from the body.

Froome first tested the nose ring during the 2014 Vuelta a España, even tweeting about its effectiveness. He then continued to wear it for much of the 2015 Tour de France, where he took his second Tour win.

It's the latest in a long line of marginal gains we have seen introduced to the sport by Team Sky, with ideas ranging from taking custom-made bedding to races to Richie Porte eschewing hotels to stay in a motorhome during the 2015 Giro d'Italia.

A number of other pros have also used The Turbine, with Jack Bobridge employing it during his unsuccessful Hour Record attempt in January 2015.