Exercise is an important part of good health and when women become pregnant, regular fitness routines should not automatically be abandoned. Pregnant women and their babies both benefit greatly when mom engages in regular moderate exercise. Women who are considered at low risk for complications and are in good physical health can continue to exercise throughout pregnancy as long as they modify their exercise routines to compensate for their changing physiques. Women who are not regular exercisers can begin a walking program, swim, ride a stationary bicycle or participate in structured prenatal fitness programs.

Exercise during pregnancy is a controversial subject. Many people believe that pregnant women should not exert themselves as they may cause harm to themselves or their unborn babies. In the African American community, an old wives tale has been perpetuated that it’s dangerous for African American pregnant women to be physically active during pregnancy. The myth grew out of the fact that so many African American babies were lost during slavery (when African American women were forced to perform strenuous, laborious tasks).

While extreme exercise is not recommended, African American women, like all other pregnant women, greatly benefit from regular moderate exercise during pregnancy. In fact, many of the diseases that are common in our culture are positively affected by exercise such as diabetes, hypertension and obesity.

James F. Clapp, III, M.D. has done extensive research on the effects of exercise on pregnant women and their fetuses. His findings are presented in His book “Exercising Through Your Pregnancy”, and are the foundation for most of what is known about the effects of exercise on pregnant women. He proved exercise is beneficial not only to the pregnant woman, but also to her unborn child.

Benefits of Prenatal Exercise for Pregnant Women

Dr. Clapp and others have found that women who engage in regular, moderate exercise (defined as 13-15 on a scale of 1-20) for at least 20 minutes 3-5 days a week tend to:

• Have shorter and less complicated labors and less need for medical intervention.
• Have more energy during their pregnancies and recover faster after delivery.
• Return to their pre-pregnancy weight sooner than less active women.
• Gain less weight during pregnancy.
• Experience an improved body image, enhanced self-esteem and a general sense of wellbeing.
  
• Experience less tension, anxiety and fatigue than less active women
• Experience a decrease in the common discomforts of pregnancy.
• Maintain cardiovascular fitness.
• Increase muscular strength.
• Experience fewer colds and other respiratory viruses.

Benefits of Prenatal Exercise for Babies

Dr. Clapp also noted that babies born to women who maintained a regular fitness regimen during pregnancy are:

• Better able to adapt to changes the changes that occur during labor and delivery
• Less fat. Babies born to exercising mothers had less overall body fat but were no more likely to be born at “low birth weight” and were fully developed compared to their counterparts born to non-exercising moms.
• More adaptive to their external surroundings. These babies tend to be alert and less startled by their environment, and able to settle and soothe themselves requiring less comforting.
• Normal in growth and development. Clapp tested children in his studies at one year and again at five years and found no stunting of growth or development.

Dr. Clapp’s work has changed how physicians and midwives prescribe exercise during pregnancy and how women should approach physical fitness during pregnancy. In 2002, the American College of Obstetricians and Gynecologists (ACOG) in conjunction with the American College of Sports Medicine issued the most recent guidelines for exercise during pregnancy.

ACOG Guidelines for Exercise during Pregnancy (Released 2002)

• Women with uncomplicated pregnancies can remain active during pregnancy and should modify their exercise routines as physically and medically indicated. Supervised exercise is recommended although not required.
• Previously inactive women and those with previous medical or obstetric complications should be evaluated before recommendations for physical activities are made.
• Active women with a history of or risk for preterm labor (labor prior to 35 weeks gestation) or decreased fetal growth should reduce activity in the second and third trimesters.

The American Diabetes Association recommends exercise as a helpful additional therapy for gestational diabetes when blood sugar levels are not controlled by diet alone. They note that prenatal exercise may be beneficial to help prevent gestational diabetes, especially in obese pregnant women.

Even with its benefits, there are times when pregnant women should not exercise or should proceed with caution when exercising.

According to ACOG, Pregnant women should not exercise if they have:

• Significant heart disease
• Restrictive lung disease
• Incompetent cervix/cerclage
  
• Multiple gestation at risk for premature labor
• Persistent second or third trimester bleeding
• Placenta previa after 26 weeks gestation
• Premature labor during the current pregnancy
• Ruptured membranes
• Pregnancy induced hypertension

Exercise with Caution

Pregnant women should exercise with caution and only with their physician’s consent and supervision if they have the following conditions:

• Severe anemia
• Uncontrolled irregular maternal heart rhythm
• Chronic bronchitis
• Poorly controlled type I diabetes
  
• Extreme obesity
  
• Extreme underweight (body mass index <12)
  
• History of extremely sedentary lifestyle
  
• Intrauterine growth retardation in current pregnancy
• Poorly controlled hypertension/pre-eclampsia
• Orthopedic limitations
• Poorly controlled seizure disorder
• Poorly controlled thyroid disease
• Heavy smoker

Pregnant women who are not at risk for complications and who have their physician’s or midwife’s consent to exercise must use care not to over do. While exercise can relieve many of the aches and discomforts of pregnancy, it should not hurt or cause any sort of physical distress. Pregnant women should feel comfortable and at ease as they exercise.

Dos and Don’ts for Prenatal Exercise.

1. Do engage in regular, moderate exercise for at least 20 minutes per session, at least 3 times per week. Maximum benefit is obtained by exercising for 40minutes 5 times per week.
2. Do continue to exercise throughout the duration of pregnancy. Clapp found that women who stopped exercising midway through pregnancy lost the benefits of exercise, and their babies did not receive the short or long-term benefits from maternal exercise.
3. Do stay well hydrated. Drink lots of water before, during and after workouts.
4. Do eat a well balanced diet. Eat healthy snacks prior to exercise sessions and have a small snack prepared for post exercise consumption.
5. Do consider the exercise environment. If the environment is warm or humid, or if there is poor ventilation, alter the exercise session by decreasing the intensity or duration as necessary to prevent overheating.
6. Do wear comfortable clothes that allow for air circulation, heat expression and adequate support of the pregnant physique. (Especially the belly, breasts, back, hips and feet)
7. Do not exercise if there is injury, disease, pain or bleeding.
8. Do not exercise to the point of fatigue.
9. Do not engage in activities that could involve changes in air pressure such as scuba diving or high altitude hiking or climbing.
10. Do not engage in activities where risk of abdominal injury is increased. (For example, roller-skating, skiing, contact sports.)

References:
James F. Clapp, III, M.D. 2002 Exercising Through Your Pregnancy, Omaha, Addicus Books, Inc.

American College of Obstetricians and Gynecologists (ACOG), Guidelines for Exercise during Pregnancy (Released 2002)
Retrieved January 2, 2008, from http://bjsm.bmj.com/cgi/content/full/37/1/6

Author: Darline Turner-Lee
Physician Assistant, ACSM Exercise Specialist
Next Step Fitness, Inc.