Simply perform the military-press movement while sitting on a ball, taking extra care not to let your back arch too much.
Start: Grip the bar as you would for a military press, but hold it behind your head, just above the base of your neck.
Finish: Press the bar up, pause, then slowly lower it to the starting position without letting it drift backward.
Grab the bar with a shoulder-width, underhand grip. This targets your front delts and triceps.
Do this exercise while sitting, without a back support.
Start: Grip the bar as you would for a military press, but hold it behind your head, just above the base of your neck.
Finish: Press the bar up, pause, then slowly lower it to the starting position without letting it drift backward.
Begin holding a barbell just above your upper chest with your knees bent ad back straight. Press the weight up until it just clears the top of your head and then immediately lower it behind you toward the base of your neck. Once there, press it back over to the front and repeat.