Women's Muay Thai

So my MMA place just started an all women's muay thai class. Today was the first class and we had 13 ladies- one even pregnant! It was a really fun class. Warm up was rough, I'm not going to lie. Coach is hard core on the basics. We jogged, knee slaps, ankle slaps, push ups, and the horrific boat pose- Then we moved on to technique. We practiced our stance and did some moving around, then added a check- which is where you kind of kick. So one, two, check. We did some shadow dancing where we moved with a teammate. Then practiced kicking each other. I have trouble swiveling, but we were able to work around it. I gotta say about 35 minutes in the pain went from eh to numbing. My lower left back was numb to the touch and tight. Sucked. I kept stretching out but man it sucks sometimes. Looking forward to next week's class. I'm hoping the pain lessens as we go on.