Activity levels during pregnancy....

Why is it fine for women to be doing insane hardcore workouts there whole pregnancy, literally gain not an ounce of weight besides that of the actual baby itself....but everyone else is told to limit activities like lifting, laundry, vacuuming and dishes, things ive been doing since before i concieved, at like the third trimester?! Lol. It annoys the crap out of me when people see me doing physical activity or lifting and freak out because my husband should be doing it all and I need to relax. Eyeroll. I'll give them relax, this shit isn't getting done by itself ya know! Lol. Rant over.