Knowing how to perform a given move with perfect form is critical, and it will help you build a solid base of muscularity. But, once you get that base, it's important to explore the full range of subtle variations of classic movements. Learning—and practicing—all these variations will help you build thicker, denser muscles by training the target muscle at slightly different angles. Over time, incorporating all the variations into your workout will build more strength, size, and balance.

The most obvious way to grow is by mastering barbell, dumbbell, cable, and machine moves. Most exercises can be done on every one of these implements; each provides a slightly different growth stimulus.

There are many other ways to introduce small degrees of change into a movement. Take the standing dumbbell lateral raise for your middle delts, for example:

• From a seated position: to decrease momentum and increase difficulty
• One arm at a time while standing: to increase the focus on each side
• On the cable: to utilize constant tension and a range of angles
• On a machine: to make it easier to work to failure
• Leaning away from a vertical post: to increase the range of motion

With imagination, the options for exercise variations are limitless.

Pro Tip: Besides working the muscle from slightly different angles, learning how to perform a particular move a number of ways can be helpful on days when the gym is crowded and lines form at the piece of equipment you need. Rather than wait in line, simply try an alternate move and your workout will stay on track and on pace.