Nike "Unlimited youth" by Wieden & Kennedy Portland

Sister Madonna Buder, also known as "The Iron Nun", stars in the latest instalment of Nike's "Unlimited" campaign.

Sister Buder is an 86-year-old nun who doesn't take too kindly to the voiceover suggesting she should slow down and take it easy. Instead, she participates in an Ironman competition – the 46th in her athletic career.

Previous ads in the "Unlimited" series have included a spot starring Bobby Cannavale, who gives a rousing pep talk to baby Mo Farah and Serena Williams.