A sports website came up with a list of the ’10 competitions you have to be crazy to enter’. These races are some of the most grueling – maybe even torturous! – physical competitions being organized today. Some of them are simply too extreme and dangerous that participants are asked to sign a death waiver. Forget about your triumphant completion of a thirty-mile marathon. Comparing that with these three will make the marathon look like a relaxing stroll through Central Park on a Sunday afternoon.

Toughguy. This race is very demanding, exhausting and grueling physically that participants are actually asked to sign a death waiver. So what makes Toughguy so tough?

For starters, there’s a little bit of life according to Forrest Gump in the way it’s played – it’s like a box of chocolates, you’ll never know what to expect. It basically is an obstacle course with a twist — one that’s truly out of this world! Its activities change every year, with challenges like ‘The Fiery Holes’ (a course with muddy, water-filled ditches and burning hales of hay), The Viet Cong Tunnels (cement pipes buried underground), The Tiger (a course with electrical cables placed between two thirty-foot nets that participants have to scurry up and over) and The Stalag Escape (involves crawling through mud underneath barbed wire).

According to the Toughguy website, they have searched far and wide for another ordeal that can rival what participants go through in this competition, and they found only one. And what else can it be? It’s a U.S. Navy SEALs training course, particularly the ‘Grinder’ Assault Course.

Iron Man. What started out as a simple question of ‘Who is the best athlete – the swimmer, the cyclist or the runner?’ evolved into one of the most grueling triathlons there is. And who better to co-‘invent’ it than a Navy officer who actually can go for a 2.4 mile swim in the ocean, take a 112-mile bike ride, then run a 26.2 mile marathon, and still live to tell the tale? If you think it’s hurdling the impossible, think again. The world’s best Iron Man athletes can do all that in the searing Hawaii heat – in under nine hours.

Iditarod Great Sled Race. Called “The Last Great Race”, it involves racing all across Alaska in the dead of winter – with no less than 16 dogs in tow. This year’s Iditarod – the 37th race thus far – began yesterday, with about 70 mushers participating in a race that covers 1,150 miles of paradox: it is one of the most extreme environments possible, but at the same time one of the most beautiful. It will take anywhere between 10 to 17 days to complete the race, what with 16 dogs to feed and put to bed each night. In a sled race, mushers make sure their dogs have everything they need before they even think about eating.