erm not that i can think of, i think the best exercise is just whenever you have a few minutes free pick up your guitar and just take a bit of time to position your fingures strum a few times then change chord, it does start off quite difficult but it will get quicker and easier sorry to repeat myself.
Time and practice is what makes you feel so good when you can finally do it.
try some simple chord patterns like G D Em C, G C D.