My doctor and Pilates instructors both told me that you can continue any exercise that you had been doing prior to your pregnancy. I can't imagine they would say not to start anything at all, but I would be weary of launching into any hard core program your body isn't used to! Walking is great exercise, swimming, as is yoga (& of course I am partial to Pilates
). In your first tri you can pretty much do it all, but once you start to get that belly, avoid anything involving laying on your back (which you see a lot of Pilates/yoga). I go to a studio and do reformer classes, they have these wedges that the pregnant ladies use while we're on our backs.
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