1) unless your arm is skinny as hell and u wanna work out till it looks like a cannon .. then yes ... not trying to offend u but just using logic wise its like drawing on a piece of elastic paper then u stretch it ... yes it will defect the tattoo ... but if u just stretch it a little bit ... it won't affect the design much ... so it actually depends on how 'far' u are going to work out ur arm

2) can't remember off the top of my head but should be minimum 1 week for the skin to have the dry skin and scabs then by the 2nd week it will start peeling annd 3rd week onwards should be smooth and u wear long sleeve it's fine i don't think it'll affect much but just remember not to press against it if not ur shirt will get dirty and it is kinda permanent ... as long as u don't wear skin tight shirts which will press against ur skin so much that there's no air for it to breathe then yes it will delay the healing process. i would suggest extra care during the first 2 weeks ... that's one of the areas that will define the end product most of the time

1.if u grow, so does tattoo, if you shrink, so does tattoo

2. 3weeks with 3times lotion care daily, expose heal faster, covered slower