Getting Plenty of Exercise

When you snore,
My imagination awakens.
No longer do I sit...
Disturbed by the sounds,
Coming from your unshut lips.

I now have learned to use this.
With added rhythms,
I dance to it.
And getting plenty of exercise,
While you unconsciously sleep...
While providing,
'My' physical fitness.

With no expense to me at all.
And you,
Are left with no clue...
Just how involved you are.