Place a decline bench underneath the Smith machine. Now place the barbell at a height that you can reach when lying down and your arms are almost fully extended. Using a pronated grip that is wider than shoulder width, unlock the bar from the rack and hold it straight over you with your arms extended. This will be your starting position.
As you inhale, lower the bar under control by allowing the elbows to flex, lightly contacting the torso.
After a brief pause, bring the bar back to the starting position by extending the elbows, exhaling as you do so.
Repeat the movement for the prescribed amount of repetitions.
When the set is complete, lock the bar back in the rack.