How tough is Tough Mudder?

'Don't worry, mate, I've got you if you fall,' shouted the diver treading water in the cold and murky depths several metres below me. At any other time, these words would have been reassuring, but as I was in the precarious position of being caught between a rock and a hard place, they did little to calm my nerves. You see, I'd got myself into a bit of a pickle on the Monkey Bar obstacle of the inaugural UK Tough Mudder race.

Eager to prove my worth by traversing the 20m-long beast - and also to reassure myself that my army skills hadn't let me down - I'd stubbornly kept swinging to the point of exhaustion. And now I was stuck. If I fell from where I was, one leg would touch the platform, the other would be in the water. It wasn't worth thinking about. If I tried to swing over to the two remaining bars, I might make it, but there was a good chance I wouldn't. Suffice it to say, it didn't quite go to plan and I had a sore groin for a couple of days.

I don't think I'd be wrong to say that Tough Mudder is the biggest name in obstacle racing. Founded by two Brits, Guy Livingstone and Will Dean, they have created a tribe and a movement, or as Will puts it in one of their videos: "We're bringing people back to the basics... And the teamwork and camaraderie part, that's what we're all about. To date, well over 1.5 million people have participated in a Tough Mudder event, and considering there were more than 50 events worldwide in 2015, that number is set to grow.

What sets Tough Mudder apart from many other obstacle courses is that it's not a race, it's a challenge, and when you enter you have to pledge to 'put teamwork and camaraderie before time' and 'help your fellow mudders complete the course'. There's no real winning time because it's not a race, so there are no timing chips or even winners.

You don't have to have a six-pack or guns the size of Arnold Schwarzenegger to do a Tough Mudder. Although many mudders do. You also don't have to go bare-chested (which must come as a relief to the female competitors!), but you do have to go in with a smile on your face and say to yourself, 'Today is about having fun.

Tough Mudder is essentially a 'team event'. I still remember my first race, which I did alone. I had to jump over a wall to get into the starting pen for one of the earlier waves. I cringed with a mixture of fear and embarrassment as a man with a megaphone shouted the aforementioned Tough Mudder Pledge, which we all had to repeat. My apprehension was that I might need help getting over the obstacles alone, but if you have a modicum of fitness and strength you can do most of them, except perhaps the pyramid where you really need teammates to build the pyramid.

However, times have changed since my first outing in 2012. Tough Mudder has just got a lot tougher, to the point where you're almost in the Crystal Maze of obstacle courses. In fact, each year the organisers come up with new obstacles that will leave you scratching your head, gasping for breath or wiping mud off your face, but never your grin. With names like the Ring of Fire, Dirty Ballerina, King of Swingers, Electroshock Therapy and Funky Monkey, you know you're in for a good time.

Once you've lost your Tough Mudder virginity, you can join the Mudder Legion - the official community of multi-mudders - by completing the Legionnaires' Loop. And every time you register for a new event, you'll receive a different coloured headband based on the number of events you've completed - from green for two Mudders to black for ten or more. You'll also get an exclusive obstacle and the chance to avoid electroshock therapy - not bad at all! And if that's not enough to keep you interested, try the World's Toughest Mudder, where you complete as many 10-mile loops as you can in 24 hours. Tempted?