Before diving headlong into a resistance training workout, it's a good idea to first warm up a bit. Getting your blood pumping, your mind focused, and your muscles prepped is an important step in preventing injury. But, just like workouts themselves, not all warm-ups are created equal.

Stretching has come under fire as of late, with some experts suggesting that it actually increases the risk of injury. Of course, there exists a great deal of research that states otherwise, so let's just say the jury is still out on stretching. However, just about everyone agrees that performing some light cardio and warm-up sets before resistance training are vital to a proper workout. Therefore, in order to properly prepare your body for the difficult workout that's soon to come, your warm-up must incorporate the use of the muscles to be trained.

While a light jog on a treadmill or five to 10 minutes on an elliptical is a pretty good way to accomplish this, an even better way is to perform the Barbell Duck-Under and the Barbell Step-Over.

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