You know nothing if you say pushup exercise are for the weak or you think push-up is very easy to do? May be thats is your thought, for it will be very difficult for a week person to do push-ups and do it properly if you think push-up is easy try and do 100 push-up in day let me see if you can continue the next day and you should also know that push-up exercise is not only the exercise that is been done in that thread for you can also add other exercises if chooses and stop referring push-up exercise as a LAME exercise that's is supposed to be done by those that are weak.