5x5 training has become very popular over the past few years. Weight training is a quirky thing as many of the popular methods have actually been around for a long time. Originally developed by Reg Park, the 5x5 method involves doing 5 sets of 5 reps, using the same resistance. That's the goal. However, if you've chosen the proper weight, you won't be able to do 5 sets of 5, at least not right away. Typically, if you've chosen the correct weight, the workout might look like this: ...