The single-arm overhead press works your deltoids, biceps, triceps, lats, and pecs -- making it one of the best upper-body exercises for men.

But by changing how you sit, kneel, or stand during the exercise, you can take an already awesome resistance movement and send its benefits through the roof, says Sean Garner, a trainer at Anatomy at 1220 in Miami Beach, Florida.

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For example, moving from a seated to a tall kneeling position better engages your glutes, Garner explains. Likewise, shifting into an in-line kneeling position (where your front and back feet are aligned as if you were on a balance beam) requires the adductor muscles on the insides of your thighs to work harder.

Watch the video above to see Garner demonstrate those two variations as well as five other stances.

The overhead press is just one example of how modifying your stance can make an exercise more effective. Start thinking about creative ways to mix it up, and the potential benefits are endless.

"Change your stance, and change your workout," Garner says.

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