Its also post baby - my pregnancy was very tough and did a number on my body. I had to be put on a high calorie high protein diet to help with SIUGR and TTTS (check out fetalhope.org) along with being on modified bed rest that caused me to gain a BUNCH of weigh, but did help my little girl to grow a bit better so it was worth it. I think my body has been ready for me to start working out for a while.