Help w/ sentence

Well, it really doesn't make any sense even when I fix it, but anyway, I have underlined the problem area:

I'm not motivated but it's different with exercising for me.

I'm not motivated but it's different when it comes to exercising for me?

Is there a shorter way of saying the above?

The way you had it written really did mean anything that make sense.

Perhap, you mean this: I am usually not very motivated but it's differnt when it comes to excercising.

For me- is not needed in this sentence because the bold part already covered the meaning.

I suppose that it is intended to mean 'Only exercise motivates me'.

Do you wish to say: I'm not motivated to do much of anything, but it's a different matter when it comes to exercising. = I don't have any real interests except for exercising.