So I emailed several acquaintances and asked for blog post ideas.  A former client suggested I discuss exercise considerations for the pregnant athlete.  Seemed like a good idea to me.  Being that I’m a man and I and my wife have no kids on the horizon, I don’t give much thought to pregnancy but perhaps I should.

Like a lot of our general fitness information, much of the popular information for the pregnant athlete falls on the very conservative side.  On some issues though there is not a consensus.  On other issues there is very little research. It seems possible though that healthy, active mothers-to-be can safely exercise beyond these conservative limits.  Most of my information came from an article titled the Pregnant Athlete from the IDEA Health & Fitness Association.  It’s a very complete and well researched article.  I suggest you read it if you’d like more information on this topic.  Meanwhile, here are a few things to consider for pregnant athletes.

Currently Exercising vs. Starting New Exercise

There is a solid consensus that it is safe for athletes to continue exercising once pregnant.  There also is a consensus that women unaccustomed to exercise should not start exercising when pregnant.

Sport and Exercise Selection

First and foremost it seems like a good idea to choose an exercise modality that’s safe.  At any stage of pregnancy, a strong enough jolt or impact to the abdomen can severely damage the fetus.  Therefore choosing low-risk sports and activities is vital.  Martial arts, downhill skiing, mountain biking (perhaps road biking too), and skating (roller and ice) are a few examples of sports in which NOT to engage while pregnant.  Running is safe for many pregnant women.  Swimming, walking, cross-country skiing and strength training may be very good ideas.

Heart Rate Recommendations

Physicians commonly recommend pregnant athletes keep their heart rate at 140 beats per minute (bpm).  Anyone who exercises knows that 140 bpm is fairly low.  The 140 bpm recommendation was put forward in 1985 by the American College of Obstetricians and Gynecologists.  The ACOG has since left that recommendation behind in favor of using the Rate of Perceived Exertion Scale or RPE.  Women should pay attention to how they feel when they exercise.  If everything feels OK then good.  Don’t exercise to blithering exhaustion though.

Heat

One concern about vigorous exercise or exercise in the heat is hyperthermia or a high body temperature and possible overheating of the fetus that could lead to birth defects.  Research however has yet to show any higher rate of birth defects among women who exercise at high intensities.  To the contrary, women who exercise can more effectively dissipate heat.  The following paragraph comes from the article, the Pregnant Athlete:

“It is during the first trimester that the fetus cannot regulate its own body temperature and is most susceptible to the mother’s.  In this period, pregnant athletes should be cautious about exercising in hot conditions and for long durations.  They should wear light-colored, breathable fabrics to keep cool and should drink water throughout the day and during exercise bouts; their urine should be diluted to the point that it is virtually clear in color.  Some experts recommend that pregnant athletes take their temperature either vaginally or rectally (orally is less accurate) immediately before their longest weekly workout and again immediately after, before the body cools down. Clapp recommends a temperature increase of no more than 1.6 degrees Celsius (3 degrees Fahrenheit [F]) and a postexercise temperature no higher than 102 degrees F (Clapp 2002).”

Strength Training

There’s not much research on strength training and the pregnant athlete.  The ACOG guidelines recommend a single set consisting of at least 12 to 15 repetitions without undue fatigue for each resistance exercise.  My guess is that pregnant women can probably lift a little heavier but looking for your PR on the deadlift probably isn’t wise during this time.  Moderate exertion sounds fine.

(I’d be quite interested to see what sort of levels of exertion we might see in pregnant women in 3rd world countries; places where avoidance of taxing physical labor isn’t an option.)

Flexibility Work

Relaxin is a hormone that increases joint mobility.  Production of relaxin goes up during pregnancy so as to soften and relax the pelvic structure in preparation for birth.  Because of this increased flexibility, it’s generally recommended that pregnant women should not seek to increase their flexibility.

(I personally don’t recommend static isolated stretching for anyone [look here, and here].  Active or dynamic flexibility work is the way to go for several reasons.)

Further Information

The National Forum on Pregnancy and Sport was conducted in Sydney, Australia, in 2001.  What follows is a summary of the medical advice presented:

• 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.

Stories of Pregnant Athletes

Finally, if you’re interested, Pregnant athletes don’t have to sit out is a story from ESPN.  Several amateur and professional athletes are profiled as they balanced their lives as competitors and mothers-to-be.

References:

Clapp, J. 2002. Exercising Through Your Pregnancy. Champaign, Il: Human Kinetics.