Question: how much weight do you lose when you ride a bike?
Answer: 'Few of us are regularly going to average over 200 watts on a long ride,' says Carey. If you divide 7,800 calories that make up 1kg of body fat by the 720 calories you'll burn riding at 200 watts for one hour, it will take you 10.83 hours – 10 hours, 49 minutes, 48 seconds to be precise – to burn 1kg of fat.