I agree with the above comment.

Do a simple experiment. Stand with your heals against a wall and place a chair in front of you to place your hands on the seat like they were handlebars. Bend at the waist only and place your hands on the chair. Without the chair as you start to bend you will want to fall forward your feet are your balance point and your center of gravity will be ahead of that point and your hands have no choice but to take the weight. Now move your heals away from the wall and as you bend forward your body will naturally move your butt back to keep you in balance and your knees will be able to bend just a little to also shift some weight back. You will be able to put any or none of your weight on your hands. You will be using core muscles though to some extent that you don’t use in the arm only position. This athletic bend though is what I like to think about when fitting myself on a bike. And in most cases people move their saddle forward hoping to take weight off the hand by thinking they are a little more upright. The problem is the crank is a fixed position and it causes greater forward lean and CG forward.

Here is a photo I found that I added some lines to showing CG and arm position of two riders. And the angle of the arms going into the angle of the fork. Sometimes a picture is worth a 1000 words.



.