Celebrating 80 years since the Royal Institution Christmas Lectures were first televised, chemist Professor Saiful Islam explores one of humankind's biggest challenges - how to generate and store energy, with guest appearances from Christmas Lecturers past. In his second lecture, Saiful investigates how humans as living pulsing machines actually use energy, asking whether it's possible to 'supercharge' the human body and increase its performance. Live experiments explore everything from the explosive potential of everyday foods, to what we put into our bodies (and what comes out!), as well as how we measure up to the machines we use every day. Saiful even experiments on himself, showing images captured inside his own stomach. Every single one of us is an incredibly sophisticated energy conversion machine, finely tuned over millions of years of evolution. So will we ever be able to improve the human body's performance? Can we ever do more with less energy?