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Start exercising before you become pregnant. Stick with safe exercises while pregnant. Aim for 30 minutes per day.
Exercising before and during pregnancy can help protect you from developing gestational diabetes.    Research has shown that women who were physically active for 4 hours a week or 30 minutes a day, before and during pregnancy can reduce their risk of GDM by about 70%.  Always ask your doctor about how much and what type of physical activity are right for you. Safe exercises to participate in during pregnancy typically include low impact exercises, such as walking and swimming. Avoid doing any type of exercise that is high impact or that has a higher potential for injuries, such as contact sports. Parking your car at the far end of the parking lot as you run your daily errands is one way to squeeze in extra activity. Most doctors will approve of 30 minutes or more of moderate exercise per day, for most or several days a week, for pregnant women.  You can incorporate several short exercise activities into your day to keep the stress on your body low while still reaping the same benefits as 30-minutes of straight activity. Make sure to monitor your heart rate while exercising and never exceed the recommended target heart rate for your age and weight.