This overhead press variation allows you to monitor your ribcage position with your free hand. It also teaches you to activate your glute and hamstring muscles to stabilize your pelvis as you move your arm overhead.
Hold the weight on the same side as your kneeling leg.
Engage your butt muscles on your kneeling leg WITHOUT tucking your pelvis. This means no "bad dog!" tail.
Ground down strongly into your front foot.
Place your free hand on your lower, front ribs. These ribs should be flush with your abdomen. Your ribcage should not move during the exercise.
As you exhale, press the weight overhead.
Notice: Did you lose the contraction of the butt muscles on your kneeling leg? If so, engage them again.
Notice: Did you lose the position of your ribcage? If so, drop your ribcage down. DO NOT BACK BEND!
I am doing this exercise with a kettlebell in a rack position, but you can also hold it with the heavy side up (this will challenge your arm's steadiness and grip strength) or you can use a dumbbell or a heavy book or a sack of rice ~ anything that feels slightly heavy for you.