The push-up hold is an isometric (held) type of exercise that will improve your chest strength and definition and will also work your core, shoulders, and arms. This exercise has another benefit apart from making you physically strong, it will definitely make you mentally “tougher”.
This is because you need to hold the push-up position (lowered down) for as much as you can. So if you think that doing push-ups is tough, think how tough this is. The main key here is to believe that you can do it and to push your limits.