Exercising during your pregnancy has great benefits – it can help prepare you for labor and childbirth and lift your spirits – but you need to approach working out with extra caution. Whether you're a regular exerciser looking to continue your regimen during pregnancy or a former couch potato looking to get moving, follow these 13 rules to keep you and your baby safe.

1. Check with your healthcare provider first

 
Inside pregnancy: Weeks 15 to 20
A 3D animated look at a baby in the second trimester of pregnancy.
If you exercised regularly before getting pregnant and your pregnancy is uncomplicated, you can most likely continue working out as before, with modifications as noted below. In some cases it's not okay to exercise during pregnancy, though, so talk to your doctor or midwife about your fitness routine to make sure your activities don't put you or your baby at risk.
If you didn't work out much before conceiving, see our pregnancy exercise guide for beginners, and talk to your healthcare provider.

2. Take in extra calories

Exercise burns calories, so make sure to eat well to help nourish and strengthen your body. While you're pregnant, you'll naturally gain weight as your baby grows. The amount you'll need to gain will vary based on your pre-pregnancy weight.
If your body mass index (BMI) is in a healthy range (between 18.5 and 24.9), you'll need to eat 300 or so more calories a day than before you were pregnant – and probably more than that if you're exercising. If you're underweight or overweight you may need to gain a little more or a little less than someone with a healthy BMI and adjust your calories accordingly.
Your doctor will monitor your weight as your pregnancy progresses and can help you figure out how to keep your weight gain on track through diet and exercise.

3. Steer clear of dangerous sports 

Avoid contact sports, as well as activities that might throw you off balance, such as horseback riding, downhill skiing, or mountain biking. Regular cycling early in your pregnancy should be okay if you're comfortable on a bike, but it's probably best to stick to stationary or recumbent bikes later in pregnancy.
Even if you're normally graceful, keep in mind that during pregnancy the increased levels of the hormone relaxin, which relaxes pelvic joints in preparation for childbirth, loosen all ligaments and joints, making you more susceptible to sprains and injury from falls.  See our list of the best kinds of exercise for pregnancy.

4. Wear the right clothes

Wear loose-fitting, breathable clothing. Dress in layers so it's easy to peel off a layer or two after you've warmed up or if you feel too hot. Make sure your maternity bra offers enough support, and choose athletic shoes that fit your feet properly and offer good support. If your shoe size has changed because of mild swelling, stash away your pre-pregnancy sneakers and buy a new pair.

5. Warm up

Warm-ups prepare your muscles and joints for exercise and build your heart rate up slowly. If you skip the warm-up and jump into strenuous activity before your body is ready, you could strain your muscles and ligaments and experience increased postworkout aches and pains.

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