A “really bad” cycling accident has left celebrity chef Gordon Ramsay with a massive bruise and a message about the importance of wearing a helmet while riding.

Celebrity chef Gordon Ramsay has been left shaken by a “really bad” cycling accident.

The presenter and restaurant owner, 57, who fronts the Kitchen Nightmares program, shared photos of his clothes being torn and helmet crushed while biking in Connecticut in the US.

In an Instagram video, he showed a nasty purple bruise which appeared to cover a significant portion of his chest.

“You know how much I love cycling and triathlons and Ironman (races) et cetera and this week, unfortunately, I had a really bad accident and it really shook me and honestly I’m lucky to be here.

“Those incredible trauma surgeons, doctors, nurses in the hospitals looked after me this week, they were amazing but honestly, you’ve got to wear helmets.

“I don’t care how short the journey is. I don’t care … these helmets cost money, but they’re crucial, even with a kid’s short journey, they’ve got to wear a helmet now.

“I’m lucky to be standing here. I’m in pain. It’s been a brutal week. And I’m sort of getting through it.”

Ramsay also captioned the post, writing that he was “doing OK and did not break any bones or suffer any major injuries but I am a bit bruised up looking like a purple potato”.

He added that he was treated at Lawrence + Memorial Hospital in New London, Connecticut, and the helmet “saved” his life.

—AAP