I was exercising practically everyday during pregnancy, including right up until the day before my water broke. My dr told me to wait 2 weeks PP before exercising again, which is tomorrow. I feel ready to work out but don't want to overdo it. I plan to start out with a PP workout that came on a pregnancy workout DVD I bought, but really I want to get right back into running.
If you are working out, how long did you wait?
Married Since 09/2006, TTC Since 09/2010
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Re: Are you working out yet?
Iris born Halloween 2013! 6 lbs, 1 oz, 18 inches long
Either way Tues will be my 4w PP mark, and I have to wait until 6w to start building back any diet or exercise over rocking, carrying or feeding DD.
DD - Juliana Joan - Born October 27, 2010 - My Little Princess

BFP 1/14/13 - M/C 1/22/13 @ 5 weeks
BFP 3/20/13 - EDD 11/11/13
Hard to keep up roller derby and competitive dressage at the same time, too. But since it's winter and we don't have an indoor riding arena...maybe I'll dig out my Riedells and get going...
If you are making 25 oz of milk (the range is 19-30 oz) and breastmilk is avg 22 calories per oz (the range is 15-40+ calories per oz) you need to take in an average of 550 calories more when breastfeeding to make breastmilk. The range is 285 to 1200 extra calories per day if you do the math.
I would aim for 600 additional calories per day. The 300 extra is on top of the 300 extra you'd be taking in for pregancy, so 600 over your usual intake.
Realize that in the immediate post partum time period your body is completely redoing your whole blood supply, rebuilding your immune system (esp if breastfeeding) and rebuilding most of the abdominal muscles, uterus, and vaginal walls. You also have a scab on the iside of your uterus that must heal. A lot of exercise immediately post partum can cause a delay in that healing, like you keep picking the scab off. (yuck!).
So be very careful with post partum exercise before 6 weeks as it can delay your healing process. Also be very careful with abdominal work, if you have a separation between the abdominal muscles, too early or the wrong kind of ab work can actually make them separate further necessitating surgical repair.