Walk into a gym and you're guaranteed to see at least one guy who looks like he can't move his upper body. We're sure he can lift a lot of weight, but he is the opposite of athletic. "One of the things I deal with at the collegiate level are athletes who say they cannot train heavy because they will get tight," states Stephen Gamma, a strength coach and athletic trainer. But fear not, lifting heavy won't make you stiff and immobile.
To get to that big and bulky point, you need to ignore several strength and conditioning principles. Guys like that likely only do exercises that build their mirror muscles, in particular their chest, shoulders and arms. They don't perform exercises through a full range of motion. And for certain, they don't do mobility work because that's a waste of time, right?
Gamma says, "I explain to my athletes that training heavy is an effective and necessary component of athletic performance enhancement, as long as they incorporate their tissue mobilization techniques (e.g., foam roll, massage stick) and movement preparation work like rolling patterns, tall and half-kneeling chop/lift patterns."