Pregnancy and Sports Participation
By: Margaret Hofmann, MEd, ACE Certified Personal Trainer

Before we discuss exercise, athletic competition and pregnancy, let me first say congratulations if you are a pregnant athlete reading this article. I hope you will take the utmost care of yourself and your baby and adhere strictly to the guidelines we are presenting here. It is important to maintain your current level of fitness, eat healthy, don’t smoke, don’t drink alcohol, get lots of rest and keep all scheduled appointments with your obstetrician. You, as a competitive athlete may require closer obstetric supervision than the routine prenatal care. Let me also state that the information in this article applies only to female athletes who are very fit and have participated regularly in sports before becoming pregnant. The information does not apply to women who are new to exercise or have not participated in high intensity exercise prior to pregnancy. Starting high intensity activity for the first time while pregnant can be dangerous to both the woman and the fetus. All pregnant women whether fit or sedentary, should obtain a doctor’s written permission before starting any exercise program.

Athletes, no matter how fit you are, this period of gestation is not the time to try new intense activities, push yourself harder than normal or try to lose weight. It can not be overstated that you should view your pregnancy as a maintenance period; a time to maintain your current level of fitness. According to the American College of Sports Medicine (ACSM), pregnant women can continue to exercise at high intensity levels as long as they do not exceed their pre-pregnancy intensity levels (ACSM 2000). The American College of Obstetricians and Gynecologists (ACOG) also advises against exercising to exhaustion, regardless of fitness level.

The guideline listed above by the ACSM reflects a welcomed change for athletes from previous held views in the scientific community regarding pregnant women and exercise. Considering in 1985 the (ACOG) published general exercise guidelines for prenatal exercise for all women, cautioning women not to exceed a maximum heart rate of 140 bpm during cardiovascular work. The ACOG also cautioned women to not perform any exercise in the supine position after the first trimester. To a competitive athlete, these guidelines seemed too conservative and confining. So, in 1994, ACOG revised its guidelines, making them less restrictive but still failed to address the upper limits of exercise. One researcher in particular, Physician James Clapp, MD, renowned for his prenatal and postpartum research, was one of the first medical experts to challenge the more conservative guidelines set at that time by the ACOG. He took the position that athletes are more efficient at handling the stresses of exercise during pregnancy and can safely exercise beyond the ACOG guidelines if properly trained and monitored. His book, Exercising Through Your Pregnancy (2002), is an excellent resource for athletes or any fitness professional or coach associated with training a pregnant athlete. If you are not already familiar with the ACOG guidelines for exercise in pregnancy and postpartum, please visit their web site at www.acog.org.

Women, understand that if you have any of the following problems you may not be able to exercise during your pregnancy:

• Heart disease


• Lung disease


• Obesity


• Severe diabetes


• Thyroid disease


• Seizure disorder


• Persistent bleeding in the second or third trimester


• Complications with past pregnancies


• Premature labor


• Pregnancy related high blood pressure
  

(Healthy Pregnancy, NWHIC, retrieved September 30, 2007, http://www.4woman.gov/pregnancy/pregnancy/fit.cfm)

Some of the other topics covered in this article include: Changes in an athlete’s body that will decrease performance level, how much is too much exercise for the pregnant athlete? What sports should they avoid during pregnancy? What are the effects of exercise on the fetus? What are the effects of exercise on the mother? When to start exercising after delivery? We will examine these issues and present the latest research on training protocols and practices for the pregnant athlete.

Women, if you experience any of the following symptoms while exercising; you should immediately stop the activity and/or exercise and call your physician.

1. Increased uterine contractions
2. Vaginal bleeding
3. Amniotic fluid leakage
4. Dizziness or faintness
5. Shortness of breath
6. Palpitations
7. Persistent nausea or vomiting
8. Back or hip pain
9. Difficulty walking
10. General swelling or edema
11. Numbness anywhere in your body

(Exercise and Pregnancy, ACE Fit Facts, 2001, www.acefitness.org)

Changes that occur that will prevent an athlete from attaining the same performance levels as before pregnancy:

1. Weight gain, by itself and in the presence of laxity of joints and ligaments and change in the centre of gravity, will cause unavoidable limitations in most sporting activities.


2. The ability to stop and start or to change direction will progressively decrease. Any attempts to substitute compensatory movements for finely tuned skill movements result in inefficient movement, decrease in competitive ability, and increase in the risk of injury.


3. Performance in sports in which endurance is important may be adversely affected by the physiological anemia commonly associated with the increased blood volume of pregnancy.

(Artal, R., O’Toole, M. (2003) New guidelines for exercise in pregnancy and postpartum have been published by the American College of Obstetricians and Gynecologists (BJSM) Online, retrieved January 15, 2007 from www.bjsm.com)

How much is too much exercise?

Pregnant athletes should exercise at a level that feels comfortable, using rating of perceived exertion (RPE) as a guide. You can view the scale on our web site in this section under “The Pregnant Athlete.” A general rule of thumb is that if it feels good, it probably is good; if, however, it feels bad, it’s probably not good. Athletes are typically very tuned in to their bodies. Most recognize the signs indicating that exercise intensity levels are too high, and they adjust their workouts accordingly. Regardless of fitness level, pregnant athletes should never exercise to exhaustion.

It is recommended that the RPE scale be used to determine the intensity of cardiovascular exercise because blood volume increases dramatically during pregnancy and while vasodilation increases to accommodate this blood flow, blood pressure can be inconsistent during the first two trimesters. As a result, heart rate is a poor indicator of exercise intensity during pregnancy.

Use caution when performing any exercise on your back after the first trimester. Lying in a supine position after the first trimester can put too much pressure on the inferior vena cava (the vein that returns blood to the heart from the torso and legs), owing to the weight of the enlarged uterus. This pressure can lead to supine hypotensive syndrome, characterized by a decrease in cardiac output, blood pressure and fetal blood supply. If you experience nausea, dizziness or breathing difficulties when supine, you are most likely a victim of this condition and should immediately discontinue lying in this position. This condition only affects 10% of pregnant women. If you have no problem exercising in the supine position after the first trimester, still proceed with caution and consider limiting the time you would normally spend in this position to just a few minutes each workout. Be aware that if you continue to do supine abdominal crunches for instance after the first trimester you have the potential for diastasis, a condition in which the rectus abdominis muscle separates at the linea alba.

In regards to strength training, pregnant athletes can continue strength training throughout their pregnancy. Never hold your breath (as during a Valsalva’s maneuver) this can reduce oxygen delivery to the placenta. Avoid maximal lifts and heavy resistances, especially when increasing amounts of the hormone relaxin are present. The purpose of relaxin is to provide increased movement in the pelvis to accommodate the growing baby and allow for an easier birth. It helps the abdominal muscles stretch during pregnancy and the pelvic floor muscles stretch during delivery. Relaxin concentrations are greatest in the first trimester, drop after the fourth month and then reach a second peak prior to labor. Relaxin is no longer manufactured by the body in the postnatal period, however its effects on the ligaments and joints linger on until about 5 months after delivery. ACOG guidelines recommend a single set of resistance exercise consisting of at least 12 to 15 repetitions (without undue fatigue,) most pregnant athletes can safely perform up to four sets of eight to 10 reps (again, without undue fatigue).

The effects of relaxin on the joints will cause an athlete to alter her flexibility program. Experts generally advise that all pregnant exercisers, regardless of fitness level, avoid stretching to maximal tension. To be on the safe side, ballistic stretching is definitely not recommended during pregnancy, to avoid the potential for muscle tears.

What sports to avoid

Experts in the fields of medicine, law, insurance and ethics presented current research, statistics and information relating to this topic at the National Forum on Pregnancy and Sport conducted in Sydney, Australia, in 2001. The following is a brief summary of the key points made by the medical presenters (SMA 2001):

• Medical evidence suggests that healthy pregnant women (with normal pregnancies) can participate in sports without affecting the course or outcome of the pregnancy, (The Panel did make some provisos in terms of type, intensity, duration and frequency of exercise.)


• Pregnant athletes should avoid maximal-intensity exercise, have a thorough cool-down period of gentle exercise, avoid excessive stretching and jerky ballistic movements, ensure adequate fluid intake and pay attention to core body temperature.


• The fetus is extremely well protected from blows to the abdomen during the first trimester (first 3 months) of pregnancy.


• The risk of abdominal injuries during sports (for both men and women) is extremely low. Current research indicates that fewer than 2 percent of all injuries, including those that occur during contact sports, involve the abdomen or chest area.


• The pregnant woman, herself, is best placed to know (generally from discomfort and lack of coordination) when to stop participating.


• Pregnant women should seek advice from medical professionals and, if appropriate, seek a second opinion.


• No medical evidence has linked adverse outcomes for the fetus (including miscarriage) to sporting injuries. Statistics and research on adverse outcomes following severe or catastrophic trauma to pregnant women relate almost exclusively to road trauma and domestic violence.

At any stage of pregnancy, an extreme blow to (or fall onto) the abdomen can damage the placenta. Later in pregnancy, as the fetus moves higher in the womb and is unprotected by the pelvis, there is greater risk of damage to the fetus itself by direct impact during sports. If there is some potential for injury, it is ultimately up to each woman and her physician to decide which sports are safe to play during pregnancy. According to the ACOG, many different types of exercise can be safe for most pregnant women. They do recommend following these guidelines when choosing a pregnancy exercise plan:

1. Avoid activities in which you can get hit in the abdomen like kickboxing, soccer, basketball or ice hockey.


2. Steer clear of activities in which you can fall like horseback riding, downhill skiing, and gymnastics.


3. So not scuba dive during pregnancy. Scuba diving can create gas bubbles in your baby’s blood that can cause many health problems.
   

(What type of exercise is best during pregnancy? HWHIC, retrieved September 30, 2007

from http://www.4woman.gov/pregnancy/pregnancy/fit.cfm)

Note: Please discuss with your physician any other sports, extreme sports or recreational pursuits that you participate in that are not listed above.

For those of you who are runners, you can continue to train safely and successfully throughout your pregnancy. Most pregnant runners report cutting back on their intensity levels by 30 to 40 percent. If you feel pelvic pressure when running, owing to the weight of your belly, you may wish to try a maternity support belt, which has been shown to alleviate some of this discomfort. Or, discontinue running for the time being if it is too uncomfortable.

Effect of exercise on the fetus

When it comes to the effect of exercise on the fetus, the three areas of concern are hyperthermia, sports injuries and oxygen deficit. The most common concern for the fetus during high intensity exercise is hyperthermia, a higher-than-normal body temperature. Exercise increases body temperature and the fetus can take on the mother’s heat, possibly leading to birth defects. It is during the first trimester that the fetus cannot regulate its own body temperature and is most susceptible to the mother’s. Mother’s should be cautious about exercising in hot conditions for long periods of time. When exercising, stay cool, wear breathable cloths and drink lots of water throughout the day and during exercise bouts. Your urine should be diluted to the point that it is virtually clear in color. One should have no more of an increase in temperature of 1.6 degrees Celsius (3 degrees Fahrenheit [F]) and a post-exercise temperature no higher than 102 degrees F. Some experts recommend that pregnant athletes take their temperature either vaginally or rectally immediately before their longest weekly workout and again immediately after, before the body cools down.

Sports injuries are very much a concern for the pregnant athlete. See the above section for more details related to sports injuries and sports to avoid.

The third area of concern for the fetus during exercise is oxygen deficit. The concern arises when a woman performs extreme levels of exercise on an inconsistent basis: then, the effect can be detrimental to the fetus. Studies have shown that when unfit women exercise at very high intensity levels, uterine blood flow decreases to the point where the fetus experiences a serious oxygen deficit. This rarely occurs when the mother is fit or an athlete. To prevent this condition, it is essential that your exercise program contain a thorough cool down period comprising of gentle exercise. Also, pay close attention to fetal movements in the hours immediately following a workout. Like us, babies stop moving when they are not getting enough oxygen.

Effect of exercise on the mother

The three major concerns for pregnant athletes in training are dehydration, hyperthermia and hypoglycemia.

It is recommended that pregnant athletes drink a sufficient amount of water throughout the day and especially when training to help combat dehydration. Blood volume decreases during the early stages of pregnancy, therefore pregnant athletes should drink 6 to 8 ounces of water for every 15 minutes they exercise. Do not exercise when you are dehydrated. One way to tell if you are dehydrated is to check the color of your urine, it should almost be clear if you are well hydrated.

Hyperthermia was addressed in the previous section. As a reminder, pregnant athletes should take their temperature weekly (vaginally or rectally) immediately before and after their longest workout (before they cool down).

Blood sugars can rapidly fall during pre-natal training sessions. It is recommended that pregnant athletes monitor their blood sugar levels weekly (using one of the over-the-counter devices that diabetics use). The goal is to maintain a level above 55 to 60 milligrams per deciliter.

When to start exercising after delivery.

We cannot overstate the importance of discussing any postpartum exercise plans with your doctor. Your pregnancy, delivery and recovery process will determine how and when you can resume an exercise program. So, get the o.k. to start exercising from your doctor and discuss with him/her your exercise plans and protocols.

The ACOG states that pre-pregnancy exercise routines should be resumed gradually, based on a woman’s physical capabilities. However, because of wide variances among women, these guidelines are not specific on when new moms may begin exercising and what types of exercises they may perform. James Clapp, MD, renowned for his prenatal and postpartum research, now recommends that a new mom start exercising early and increase her exercise slowly. Clapp has found that women usually resume some type of exercise without complications within 2 weeks after giving birth. He states in his book, “We have drawn the conclusion that, if [postpartum exercise] doesn’t hurt or cause the woman to bleed heavily, it’s ok.”

Benefits of exercising within 6 weeks after giving birth:

• Opportunity for weight loss increases.


• Urinary incontinence decreases.


• Diastasis recti shrinks to stabilize abdomen.


• Favorite activities can be resumed more quickly.


• Low back pain is reduced or eliminated.


• Energy level improves significantly.


• Anxiety, depression and other mood disturbances decrease significantly.
  

( Sources: Sampselle et al. 1999; Richardson 1998; Koltyn & Schultes 1997; Clapp 1998; Creager 2001)

Core strengthening exercises can be started early after delivery (with your doctor’s permission) sometimes within 24 hours after giving birth vaginally or by cesarean section. Core exercises focus on the working relationship of the abdominal, back, diaphragm and pelvic floor muscles. The key core muscles include the transverse abdominis, the innermost abdominal muscle, which stabilizes the abdomen; the multifidus, a muscle deep in the back that works synergistically with the transverse abdominis to stabilize the back; the pelvic floor muscles; and the diaphragm, the primary breathing muscle, which works in unison with each of the aforementioned muscles. For all people, the core muscles provide support and stability for basic daily activities, but a new mother relies on strong core muscles for new daily activities, all of which include lifting and balancing her baby. By strengthening the core, a new mom can prevent low back pain and incontinence, improve posture, strengthen weak abdominal muscles and reduce the occurrence of a diastasis recti, (when the rectus abdominis muscle separates at the linea alba).

The core exercises that can be started early within 24 hours after delivery are: Diaphragmatic breathing, pelvic tilt, hip lifts, supine transverse abdominis exercise, multifidus exercise, kegels, log rolling and walking. One should progress from the proximal muscles (the deeper pelvic floor muscles and transverse abdominis) to the distal muscles (the rectus abdominis). Usually postpartum exercise programs are divided into three main phases: Phase 1 exercises are within 24 hours after giving birth. Phase 2a exercises are 4 to 6 weeks postpartum or once a woman can complete Phase 1. Phase 2b exercises are 6 or more weeks postpartum or once a woman can complete Phase 2a. Phase 3 exercises are 3 or more months postpartum or once a woman can complete Phase 2b. A list of these exercises can be provided by your physician.

To see illustrations of the abdominal muscles, go to www.bodysmart.com.

Most common exercise mistake

One mistake that women make after giving birth is to try immediately to regain abdominal tone by performing hundreds of sit-ups. Sit-ups do strengthen the rectus abdominis, the most superficial layer of the abdominals. However, performing sit-ups with a weak transverse abdominis impairs its ability to “corset” and stabilize the abdomen, possibly exacerbating a diastasis recti.

Note: Learn how to exercise the transverse abdominis before and during pregnancy, this may shorten your time in labor. The transverse abdominis muscle assists with pushing out the baby in the delivery process.

EXERCISE PRECAUTIONS

1. Until the gap is reduced, a woman with a diastasis recti of more than two finger-widths should avoid doing strenuous activities such as sit-ups, crunches, double-leg lifts, leg-lowering exercises and jackknife positions; sitting straight up from a supine position; and lifting objects heavier than her newborn baby. When lifting her baby, she should tighten her abdominal muscles by pulling the navel toward the spine. She can perform the exercises listed above in (when to start exercising after delivery) within 24 hours after giving birth.
2. If a mother delivered her baby vaginally, she should wait at least 4 weeks before performing the quadruped transverse abdominis raise to limit the possibility of fatal air emboli traveling into her uterus.
3. If you experience vaginal bleeding, bright-red bleeding, pain, weakness or dizziness during exercise, stop immediately. You may need to reduce the intensity, frequency, duration and/or type of exercise in your next training session. If any of these symptoms persist, contact your obstetrician.
4. Avoid bouncing motions on a stability ball until 4 weeks after the birth or until the bouncing motion does not cause any discomfort in the pelvic floor, abdomen or back. Bouncing on the ball should be performed only if you are continent of urine.
5. Six weeks after having a baby, a woman may gradually resume her pre-pregnancy exercise routine and pace herself to accommodate her current physical capabilities (ACOG 1994).
6. Women should drink a minimum of 10 glasses of water every day after delivery; if they exercise and breastfeed, they should drink more. James Clapp, MD, author of Exercising Through Your Pregnancy, recommends that women monitor their urine color to determine whether or not they are drinking enough water. If your urine color is dark, you should drink more water; if it is light-colored, you are probably drinking enough (Clapp 1998).
7. A woman who has or is at risk of chronic health problems such as heart disease, diabetes or obesity should consult a physician before beginning a new physical activity program after a vaginal or cesarean delivery (U.S. Department of Health and Human Services 1996).
8. If you have a breast, vaginal or incision-site (episiotomy or cesarean) infection, you should consult your obstetrician before initiating or resuming your exercise regimen.
9. Exercise in the early postpartum stages can be beneficial, but if you do not feel ready to exercise or would rather rest than exercise, then resting may be the better choice for you.

In closing, let me reiterate the importance of discussing all exercises or training protocols with your physician during pregnancy and postpartum. Your exercise plan will be unique to your health condition. Always pay attention to how you feel and make adjustments accordingly. Stay well hydrated and don’t exercise to exhaustion or in extreme weather conditions. Use caution with exercises in the supine position after the first trimester. Maintain your current level of fitness and in the later stages of pregnancy don’t be surprised if you have to slow or discontinue certain activities or training regimes. If you are unsure about anything, call your physician for help. We want you to be safe and healthy as you prepare for the arrival of your baby. Good Luck.

RESOURCES

Books

Exercising Through Your Pregnancy by James F.Clapp, Addicus Books 2002
Pre- and Post-Natal Fitness by Lenita Anthony, ACE 2002
Exercise During Pregnancy (IDEA Resource Book), IDEA 2001

Articles
“The Core of Postpartum Training” by Caroline C. Creager, IDEA Personal Trainer, November-December 2002
“Breast-Feeding for the Active New Mom” by Janet Weller, IDEA Health and Fitness Source, June 2002
“The Pregnant Athlete” by Lisa Druxman, IDEA Health and Fitness Source, June 2003, 43-49

REFERENCES

American Council on Exercise (ACE). 2001. Fit Facts on Exercise and Pregnancy, www.acefitness.org.
American College of Sports Medicine (ACSM). 2000. ACSM’s Guidelines for Exercise Testing and Prescription (6^th ed.). Philadelphia: Lippincott, Williams & Wilkins.
American College of Obstetricians and Gynecologists (ACOG). 1985. Exercise During Pregnancy and the Postpartum Period. Technical Bulletin #8. Washington, D.C.: American College of Obstetricians and Gynecologists.
American College of Obstetricians and Gynecologists (ACOG). 1994. Exercise during pregnancy and the postpartum period. ACOG Technical Bulleting Number 189---February 1994. International Journal of Gynaecology and Obstetrics, 45(1), 65-70.
ACOG Committee. Opinion no. 267: exercise during pregnancy and the postpartum period. Obstet Gynecol 2002;99:171-3.
Artal, R., O’Toole, M. 2003. New guidelines for exercise in pregnancy and postpartum have been published by the American College of Obstetricians and Gynecologists. Br J Sports Med; 37:6-12.Retrieved January 15, 2007 from http:bjsm.bmj.com/cgi/content/full/37/1/6/.
Clapp, J.F. 1998. Exercising Through Your Pregnancy. Champaign, IL: Human Kinetics.
Creager, C.C. 2001. Bounce Back Into Shape After Baby. Berthoud, CO: Executive Physical Therapy.
Koltyn, K.F., & Schultes, S.S. 1997. Psychological effects of an aerobic exercise session and a rest session following pregnancy. Journal of Sports Medicine and Physical Fitness, 37(4), 287-91.
National Women’s Health Information Center (NWHIC). Healthy Pregnancy. Retrieved September 30, 2007 from http://www.4woman.gov/pregnancy/pregnancy/fit.cfm.
Richardson, C. 1998. Therapeutic Exercise for Spinal Segmental Stabilization in Low Back Pain: Scientific Basis and Clinical Approach. London: Churchill Livingstone.
Sampselle, C. M., et al. 1999. Physical activity and postpartum well-being. Journal of Obstetric, Gynecologic and Neonatal Nursing, 28(1), 41-9.
Sports Medicine Australia (SMA). 2001. Participation of the Pregnant Athlete in Contact and Collision Sports. Fact sheet obtainable through Sports Medicine Australia Web site (www.sma.org.au).
U.S. Department of Health and Human Services. 1996. Physical Activity and Health: A Report of the Surgeon General. Atlanta, GA: U.S. Department of Health and Human Services, Centers for Disease Control and Prevention, National Center for Chronic Disease Prevention and Health Promotion.