Yoga (modified so that you are not flat on your back and no inversions/headstands) - walking, water aerobics and swimming are all excellent in late pregnancy. Light jogging if you are accustomed to the exercise. The second half of pregnancy is not the time to start a strenuous exercise regimen because your placenta was formed based to accommodate the amount of exercise you were doing in the first half of pregnancy (oversimplified but that's the best I can do! LOL)
But any activity that you are used to, or low impact exercises like swimming, are fine during the last months. It is vital that you don't overstretch (joints are too loose!) Don't become overheated, and pay close attention throughout any activity to make sure that you are feeling fine. Sports with lots of twisting or sudden moves (tennis) are usually not recommended either. You want to get the blood flowing, keep the joints supple, etc - not train for competition.
at 11:17 PM on Jun. 5, 2009