Firstly, marines' pressups are so damn hard! I can only do a couple at a time, i was doing ok with my pressups, now i have to start from sqaure one!!! I need clarification and justification!, I only know of royal presssups the bits of info i've picked up on other posts, please someone give me a full and proper account of how to do them eg. are the arms allowed to come out from the body at all, cause i can hardly keep them in!
Also, can someone please tell me why they do these pressups as opposed to the ones done by the army, are they better?, how?, and why the hell are they so damn HARD!!!!

Nothing worth doing is ever easy.