Lie on a bench under a Smith machine bar and grasp it with a reverse (underhand) grip at about shoulder width. Unrack the bar and lower it in a controlled motion toward your chest, then press it back up by extending your arms while keeping your elbows tucked and core engaged. This grip shifts emphasis toward the chest and triceps.
Log your smith reverse grip press sets in 1RM.fit and watch your estimated 1RM update automatically as you get stronger.