My brother is 15 years old and me and him trains a lot and he can only do 45 perfect form push-ups and 60 sit-ups and he want to do 80 push-ups and 80 sit-up and hes wondering if he will be able to do more when he get a little older?

Most likely: Although I can’t give you an exact number of push-ups and sit-ups that a 15 year old can do, most 15 year-old males still haven’t fully developed their muscle potential. As someone goes through the rest of puberty and develops more muscle, as well as continuing to work out on a regular basis and keep up with doing those exercises, one should be able to do that eventually. Stay healthy!