My 3 yr old female EB seems stiff when she gets up from napping. She is a rescue and i've only had her about 3 months, she's been vetted and is on a good dog food now. We walk twice a day the distance depends on the outside temp. We walk at her pace, she seems fine while she's up and moving. When we come home from the walk and she realized the a/c is on she either sits or lays on the vent, which i'm sure doesn't help her stiffness. She always lays on the same side and the stiffness seems to be in her rear/hips, after a few steps she seems to be loosened up again. My question should i give her a supplement? Any suggestions on what would help?