There are some people in the world that actually enjoy exercising. Physical activity for them is a necessity that improves their overall quality of life. They love the endorphin rush that movement provides them and the benefits it brings to their healthy bodies. For others, the more couch potato variety they can’t imagine what people enjoy about a extreme cycling class or a 5K marathon run. It sounds more like torture to someone who doesn’t exactly exercise. For the people who seriously want to push their physical fitness to the test there are endurance races all over the world that combine a bunch of different activities into a killer race. The challenge of these extreme races are exciting to anticipate. Training for an endurance race involves total commitment to a very physical regime. Being in one of these races requires bravery, and physical skill. If you decide that you want to sign up for one of these events get to the webpage early, because oddly enough these races fill up fast and are usually sold out of spaces well before the month of the race. So the question is are you ready to race? To race or not to race, you’ll take it to the limit with this type of challenge. Here are the 13 toughest endurance races in the world.