Stepping back into it

I did 40 minutes of stepping tonight...not my best effort, but hey, at least I did SOMETHING!  I even did a few sit ups too.  My hips and lower back have been really giving me some trouble lately.  I think it's just that I'm not stretching enough after workouts.  So, I'm trying to make a better effort to stretch and since I'm down there on the floor....a few sit ups will help the front side get stronger.