Curl then press in one flowing rep that smokes arms and shoulders.

Keep the neutral grip the whole way, don't rotate your wrists during the press.
The neutral-grip curl loads the biceps and forearms on the way up, and flowing straight into an overhead press means there is no rest at the top, just more work. Sitting on the bench strips out the leg drive and body english that standing combos invite, so the arms own every phase. It is a dense arm-and-upper-body builder for short sessions, one pair of dumbbells, zero downtime.
The curl, for almost everyone. Pick dumbbells you can hammer curl strictly, and the press portion will feel manageable. Choosing a pressing weight and cheating the curls up defeats the pairing.
Consistency and comfort. The neutral grip flows naturally from curl to press without a wrist rotation mid-rep, and pressing with palms facing in is a friendly shoulder position for most lifters. Rotating grips halfway adds a fumble, not a benefit.
The bench removes leg drive and torso sway, so the curl stays a curl and the press stays a press. Standing versions drift into push-press territory the moment the set gets hard, which cheats exactly the muscles you picked this to train.




