in stead of featuring just one activity such as running or weight-lifting, crossfit tries to integrate gymnastics, teack and field skills, and bodybuilding into a short and intense workout. a workout of the day (or wod) may involve doing 20 pushups, followed by ten pull-ups, and then an 800 meter run-then repeating the set as many times as possible in 20 minutes. because the workouts change every day, the body does not easily adapt and is always challenged. of course, a danger is that some people go overboard and risk injury or, at the very least, suffer aches and pains for a few days. but for people who like to push the limits of fitness and strength-there are many police officers, firefighters,and military people who follow it -crossfit is the key
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