Have you ever had to put anything overhead that was a tad heavier than say the light dumbbells you strict press. Try to toss a increasingly growing child up into the air for fun. Because this actually is a game that kids love, just watch the height, as I can’t condone flinging a small child 20 feet into the air, asking for a amateur cheerleading fail. Either way overhead is a challenge for a lot of people, especially when you add some weight.
Enter the push press. Finding a stable position and then using your hip to propel the bar upwards via the shelf that you created with your shoulders, is a very efficient way to send a weight to overhead. Take the bar out of the rack, with your hands just outside your shoulders, and the bar in the palm of your hand. Depending on flexibility, this will determine if the bar is in your finger tips or the palm of your hand. A huge leg up here is to have the bar sitting on your shoulder. Keeping your elbows down beneath the bar is advantageous as well since this movement ends with a press. While driving your shoulders up to create a shelf for the bar, and keeping a tall chest, dip down 2 inches with a vertical torso, and then explode upwards much like the beginning of a jump. In this version your feet stay on the ground. When your hips extend your next push comes from your shoulders, sending the bar off of your body, then the final press comes from your arms. This movement consists of a controlled down and an explosive up. There is no down to follow. Once your legs extend, they stay straight. Bending them again makes this something else, and that is not what we are doing. (see push jerk)
Either way, generating force from your hips to move a load with your shoulder is next level. More work efficiently is the game. When you have kids, everyone is tired. Efficiency of movement should be paramount. Next time you need to go overhead, keep your whole foot on the ground and use your legs. It sure makes it a whole lot easier.