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Sasha is my 10 year old JRT we moved 6 years ago from somewhere with a lovely walk to an area where there is only a playing field for her to have her exercise. She doesn't want to play for any longer than she wants to play and I am worried that this may not be long enough anymore. I can no longer, due to illness, get on the floor and play with her with a ball like I used to. Do JRT's go off exercise for too long when they are 10 and over?