A wounded ex-soldier who survived horrific injuries from a grenade attack will today celebrate his astonishing recovery by taking part in what has been dubbed the world’s toughest triathlon.

Sean Donlan, who lives in a village near Cleckheaton, is part of a Help for Heroes team that will take on the Enduroman Arch to Arch challenge.

The 27-year-old joined the Army at the age of 16 and trained as a vehicle mechanic. A Lance Corporal, he was serving with the 2nd Royal Tank Regiment in Afghanistan when, in April 2011, he was hit by shrapnel from a rocket-propelled grenade.

He woke up in hospital four weeks later, surrounded by his family who had been told that it was unlikely he would survive his severe brain injuries.

He was left almost paralysed down one side, deaf in his left ear and unable to speak, and part of his skull was removed to relieve his symptoms.

He spent months in hospital undergoing countless operations, and intensive physio and speech therapy has resulted in vast improvements.

The 24 wounded, injured and sick military personnel and veterans on the Help for Heroes team will take part in an 87-mile run, for which some of the team will use wheelchairs, from Marble Arch to the south coast, then swim the English Channel, and finally cycle 181 miles to the Arc de Triomphe in Paris. Some of the team will pedal a hand cycle with their arms from Calais to Paris.

Sean has completed much of his training for the challenge at the Help for Heroes Phoenix House Recovery Centre in Catterick, North Yorkshire.

Sean Donlan

He said: “It’s amazing to join the team. It’s great to raise money for the charity that has helped me and that I always try my hardest for and just to make the team itself has made me a happy person.

“Training gets me out and about. It gets me back up to Catterick too. It’s not easy training but it’s very enjoyable once you have finished. I really enjoyed the bike. I cannot stand the run but it has to be done.

“The support of the military, the support activities team at Help for Heroes Recovery Centres and Vista Home Care in Cleckheaton, that taught me how to speak again, all helped me get to the stage I’m at now.

“Before injury, when I was fit, I would never have dreamed of being capable of doing these endurance events, so to be competing in them now, after all I have been through, is unbelievable.”