A Different Exercise=aches and pains

Oh my goodness! Today I didn't walk and I didn't lift weights but what I did do was play a little tennis, something I haven't done in a very long time. I'm feeling achy already and I'll be lucky to be able to climb out of bed tomorrow morning. What is it about using muscles that are normally sitting dormant. There is a price to be paid that's for sure. Aside from the stiffness and soreness, it was a lot of fun to hit that ball around again. Maybe I'll have to consider taking the sport up again. (I may change my mind about that when I see how I feel in the morning....)