Ketones: fair or foul?

What are ketones?

‘Ketones are an energy source produced by the liver during fasting or periods of low carbohydrate intake,’ says Peter Hespel, professor in exercise physiology at Belgium’s Leuven University and collaborator with QuickStep Alpha Vinyl. ‘We all have ketones circulating in our blood but generally at very low levels.’

If ketones are produced when fasting, how does that help cycling performance?

This is where we must differentiate between ketones, produced within your body, and ketones, a lab-made synthetic supplement. The idea first mooted by ketone researcher Professor Kieran Clarke of the