If you find the 3/4 push-up still too much to begin with you can press from a four point kneeling position.
This exercise will work your entire core, but the primary muscles used are the chest muscles (pectoralis Major), back of the arms (triceps) and the front of your shoulders (anterior deltoid muscles)
Tips:
Breathe out on exertion (the push-up phrase) and in on the lowering.
When performing the 3/4 push-up keep the hips lower than the shoulders.
Draw the elbows back towards the rib cage. This will make the push-up more triceps dominant and place less pressure on the shoulders.
Try to keep the spine in neutral, no dipping or raising the head.
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