Giratina and Shaymin didnt really have a name change, this Kyurem does have a name change, so why would they do this, this time around?? O and heres the proof that it isnt "Black Kyurem and White Kyurem" like we all think but rather they are getting supposedly their own Seperate Names
To increase mass on your chest just basically eat foods that make you gain more mass. Such as Chicken, Rice, Peanut Butter, Bananas, and so on. Then try some good chest exercises for example: Bench Pressing, Sit Ups, Dumbbell Presses, and of course there is plenty more you can look up.