Fitness tip: Many people struggle to perform a proper push-up. Here are a few tips that I find extremely helpful, and can improve your form right away. This applies to all types of push-ups, including the hands elevated variety. At the top of the push-up you should:
1) Set your body so it is in a straight line from head to heels. Your eyes should be looking straight down, which would indicate that your neck is in proper alignment. Look at the same spot on the floor the entire time. If you notice that you are suddenly looking back towards you feet, your neck has likely dropped, and if you are suddenly looking up, it means that you are hyperextending your neck, which is not good.
2) Squeeze your glutes. This will stabilize your pelvis and prevent it from dropping or rotating.
3) Gently tuck your ribs towards your hips so you are in a slight hollow body position. This will allow you to engage your anterior core, which in turn will give you the much needed stability around the spine, and will allow you to generate more strength with your upper body. Also, your pelvis can be in a slight posterior tilt. Many people can't perform push-ups because their core muscles (including glutes and scapula stabilizers) aren't strong enough. The push-up is a full body exercise.
4) Take a deep breath into your belly (360 degrees of air around your spine) and brace your core. This will give you the stability around your spine that you need to perform the exercise properly.
5) Lightly press your tongue against the back of your upper teeth. This subtle move will activate the deep neck flexors, which will help keep your neck up, and will prevent the muscles on the lateral and posterior part of your neck from overworking and tightening up. I also find that this strategy helps activate the core muscles.
When you are a beginner, you might need to ''reset'' at the top of each rep you do. After awhile, you should be able to do multiple reps in a row before you need to reset. In this video, I am doing a very advanced form of push-up. I am ''resetting'' at the top of each rep, and am employing all of the tips that I listed. Notice that despite the difficulty of this type of push-up, my alignment remains good the entire time, and there is no rotation occurring in my pelvis or spine.
While all of this information might seem overwhelming at first, keep practicing. Eventually it will become second nature, and you will become unconsciously competent, which is the ultimate goal
Give these tips a try, and see if they make your push-ups feel better.