This time of yr they should be fit as fleas anyway. Good grub goes without saying , Decent bed, And work will have them with all the mucsle they need..
So dont get that heavey mucsel look mostly sighthound types with a lot of Gh, Whip, Bull seem too be heavey with mucsle. I wouldnt worrie about it i dont really like heavey mucseled dogs anyway just somthing with pleanty of flow about it