COLLAGEN HELP PLEASE

Hi im a 21 year old male and im doing alot of training for martial arts and also trying to build very strong and toned body. Now i herd alot of hype about collagen and that it is used for rebuilding body tissue like tendons bone muscles and much more, however all i find is recomendations for older people, mostly seniors. So my question is for my age i know my bodys collagen is still prety high however what im wondering is could i use collagen supplement to rebuild my tendons and bones while training or is this not good for me ??  Im kinda lost the health food store didint know anything about the fact if young adults take it to strengthen tendons and to  build a stronger more flexible body, all they could tell me is that seniors usually take this for lack of collagen in there systems due to age and osteoartheritis and things like this.
Any information is very appreciated.

Thanks