Today I also did yoga. Thought it would be an easy break instead of running and weights.....I was wrong. I didn't even do very advanced stuff mostly planks and stretches but as soon as I stood up afterwards my legs were shaking!! It's amazing what a different angle will do.
TIP: Do different exercises. Everyone has their favorite exercise, but switching it up can move your muscles in different ways getting you more tone or out of a rut! When I just want to try something I go to the library and pick up a tape. If I really like an exercise I can buy it, but there's no pressure to start a whole new routine. This works for me since I live across the street from the public library but if you don't see what your friends have and swap. [I've read this in magazines about not getting bored and changing up how muscles move but I can't find a link right now sorry, but I swear the mags have had it!]