For male bodybuilders, the front military press works the upper chest more than the back version, based on muscle activity during both lifting and lowering the weight.

When male bodybuilders do front shoulder presses with a barbell, their chest muscles work way harder than when they do the same move with the bar behind their head.

For competitive male bodybuilders, doing the back barbell military press fires up the rear shoulder muscles way more than the front version — in both the lifting and lowering parts of the move.

If you're a male bodybuilder, doing the back barbell shoulder press lights up your side shoulder muscles more than the front version — both when lifting and lowering the bar, and the difference is really big.

If you're a guy who lifts weights and does overhead presses, doing the front version might fire up your front shoulder and chest muscles more than the back version — so it could be better for building those areas.

When bodybuilders lower the bar behind their head during a military press, their front and rear shoulder muscles work harder than when they do the same move in front of their head.