I'll be delivering on Friday via induction if Rebecca doesn't come on her own before then. I've been exercising regularly throughout my pregnancy. My intensity level has naturally and gradually decreased over the course of my pregnancy, but up until last week I was still doing cardio 2 - 3 times a week ( with a fair amount of high impact ) and lifting weights twice a week, yoga when I could fit it in. I have pregnancy videos, but the only ones I've actually done this pregnancy have been yoga ( because I didn't do any yoga at all prior to becoming pregnant ). I took a week off to recover from a cold, and when I came back to my workouts, the baby had dropped low enough that even power walking was very uncomfortable, so I've decided to stick with yoga for the rest of my pregnancy.
I obviously can't report on my labor/recovery/weight loss yet. I CAN say that out my my 5 pregnancies, this has been by far my most comfortable. I have felt better than in any of my other, less fit pregnancies. This whole fitness thing has been a journey for me, so each pregnancy I have been progressively more fit going in and remained more active throughout. In general I have felt better and better, have had easier labors, and recovered more quickly in terms of energy, regaining ab tone, and weight loss each time, despite the fact that those things are supposed to get more difficult as you age. Obviously I hope that trend will continue after this baby is born.
Have I gained less weight? Yes and no. I gained most with my 1st, least fit pregnancy ( 40 lbs ), but this one is coming in second with a 29 pound gain so far. BUT I feel more comfortable with my weight gain, and haven't had any "How will I ever take it all off?" moments. I'm not worried about it. I've taken it off before. I can do it again. If it had done NOTHING else for me, the exercise was worth every moment for the psychological benefits and stress control.
There actually ARE several scientific studies on the effects of exercise in pregnancy. You can read about them in the book Exercising Through Your Pregnancy by Dr. James Clapp, which I think should be mandatory reading.
Fit preggos have babies who are also fit, and better able to withstand the stresses of labor and delivery. They get "exercised" right along with you when you work out. They have bigger placentas, so baby gets more of what he/she needs, and has more of a buffer in emergency situations. Fit preggos TEND to deliver earlier ( though there are fewer pre-term deliveries ) and have shorter labors, although obviously that varies from woman to woman. The list goes on and on. Like I said, Dr. Clapp's book is stuffed with scientific studies supporting the benefits of exercise before, during, and after pregnancy. There were times when fatigue tempted me to skip a workout. Knowing the benefits to my baby got me moving. How much better I felt once I WAS moving kept me going.
That said, I'm a huge proponent of listening to your body ( at all times, but ESPECIALLY during pregnancy ). The low energy days when I had to force myself to get moving "for the baby," and I DIDN'T feel better after a short time, I stopped. Just because I was doing a fair amount of high impact and squats with a 35 lb barbell at 37 weeks, that doesn't mean that every pregnant woman can OR should. Those activities felt comfortable to me, and I was choosing workouts that I enjoyed. I was able to maintain a Kegal contraction before, during, and after, plus I had no urine leakage problems, so I knew I wasn't unduly stressing my pelvic floor. Any moves that felt uncomfortable, I modified. Any workouts that felt too fast or intense, I stopped doing. I felt GOOD afterward and the next day. When that was no longer the case ( as of last Friday ), I stopped and went to just yoga. If that stops feeling good this week, I'll stop with that too. I have nothing to prove to anyone, and neither does any other pregnant woman. We just need to do the best we can for ourselves and our babies, whatever that translates into for any particular pregnancy & for any particular woman.
Okay, I'll stop my rambling now.
Good luck!!