Rugby hunk Danny Cipriani got pulses racing on Saturday when he ran a fitness boot camp on Clapham Common.
Lucky bidders from voucher website Groupon were put through their paces during a 60-minute fitness session.
More than 800 people went online to bid for the chance to take part in the session, along with raising money for the charity to fund research into heart disease and advanced surgical techniques.
Cipriani said: "Currently only 6 per cent of men and 4 per cent of women in England do the recommended levels of exercise, this is something we need to change.
"This boot camp was the perfect way to show people how exercise is not only good for your heart but can also be great fun."
The Beach Body Beautiful Boot Camp is a joint partnership between Groupon and Heart Research UK.