ExRx.net

I've been doing bent over rows and dumbbell military presses (if that's the right name for the straight up press) with my hands oriented as if I were holding a barbell. Is there any advantage to rotating so the underside of my wrists face inward?

The main advantage is if you have elbow pain when you're doing rowing movements. Neutral rows (hands held as you describe in your last example) are less stressful to the elbows than pronated (barbell style) rows. I'm not sure if it makes as big a difference during pressing movements.

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Thanks, TimD

For both I'd recommend more of a neutral grip (Palms facing each other).

For rows, it's more of a natural way for lats (back muscle) to work. When grip is hugely pronated, lats are on a stretched position, the neutral position (or close to it), is most natural in my mind to get full contraction on the lats. Neutral grip gets a nice range of motion without straining the wrists, plus a strong contraction when you "close your armpits". When doing BB rows, I usually don't have enough ROM, and have to bend from my wrists to get the rest of the movement.

For press, close to neutral grip is usually suggested when someone has shoulder problems. When pressing, different grip affects the muscle activation. I always recommend forming an arrow shape with your shoulder and arm. Again, this too feels like the most natural range of motion. You'll get great tricep and chest activation as well.

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Prove the impossible!

a neutral grip gives the tendons in your shoulders s bit more room to breathe