Weight training during pregnancy

Now that women are weight training seriously in ever-greater numbers, it is inevitable that many will become pregnant and worry about how best to adapt their training to its demands. The general good news is that active women with normal, low-risk pregnancies do not have to give up their beloved weight training in order to keep themselves and baby healthy.

Early guidelines about training during pregnancy were largely based on speculation and expectations about middle-class women’s roles, rather than on clinical research and demonstrated results in a particular population. Luckily these guidelines have been updated and now reflect women’s experiences more realistically. The 1994 bulletin of the American College of Obstetricians and Gynecologists indicates that “[t]here are no data in humans to indicate that pregnant women should limit exercise intensity and lower target heart rates because of potential adverse effects.”

Similarly, the 2001 Canadian guidelines indicate that regular exercise has a number of benefits and few drawbacks for women. And yet, a recent study shows that in the United States, “Half of obstetricians do not routinely discuss exercise. The majority is hesitant to advise sedentary gravidae to start exercise and is conservative with respect to exercise intensity. Action may be needed to convince more Obs to routinely recommend exercise to all healthy patients.” (Entin, Pauline and Kelly Munhall. “Recommendations Regarding Exercise During Pregnancy Made by Private/Small Group Practice Obstetricians in the USA.” Journal of Sports Science and Medicine 5 (2006): 449 – 458. Full text)

Ideally women should be fit and active before getting pregnant, so if you are thinking of conceiving, begin an exercise program now (but of course, if you’re reading this, you’re probably already exercising!).

One of the important truisms about activity during pregnancy is that pregnancy is not the time to begin a strenuous exercise program. In fact, pregnancy is not the time to make any drastic physical changes.

However, women who are already accustomed to regular activity and exercise generally find pregnancy no disruption to their normal routine, and previously sedentary women can safely begin a moderate exercise program as late as the second trimester.

For ideas, check out Lauren Brooks’ new DVD, Baby Bells. Lauren (see photo to the right) is a certified kettlebell coach who’s written an article elsewhere on this site. She trained with kettlebells throughout her pregnancy.

general concerns

There is a bit of folk wisdom which suggests that women should not engage in exercise after having had a baby. There are dire predictions about souring the milk and so forth, having your uterus fall out, or heaven knows what. This is as realistic as the tooth fairy. Studies have shown no increase in acidity of breast milk after mom’s exercise. Regular postnatal exercise reduces or eliminates most of the unpleasant postpartum symptoms of physical and mental stress, depression, and so forth, as well as promoting a faster recovery. Postpartum exercise appears to help promote insulin sensitivity.

Furthermore, children of moms who exercised before, during, and after pregnancy were shown to be relatively leaner themselves five years later.

While exercise during pregnancy has clear benefits, many women tend to cease doing it. The two primary reasons for quitting exercise are significant weight gain and interestingly, the demands of care for other children.

This points to the importance of support systems (such as child care) for pregnant women in order to enable them to continue to exercise during pregnancy.

“Muscle conditioning” exercise (i.e. weight trainng) is considered low-risk and safe. Self-monitoring of training is essential during this period, however, using tools such as the rate of perceived exertion (RPE).

This is a good time to keep a journal that records eating, training, workout reports, notes on how you feel, heart rate, recovery, etc. Here are some general concerns for training during pregnancy.

joint laxity

This is a crucial issue for weight trainers. The body “softens” connective tissue in order to prepare for delivery. Great for pelvic expansion during the crucial moments, not so great for folks trying to keep their kneecaps stuck to their legs during training. On the plus side, strong muscles help to hold things together and improve overall stability, so strength training will be helpful as long as care is exercised.

overheating

Another significant issue for weight trainers. Dress to stay cool, drink lots of fluids (even though you’ll feel like you have to pee every ten minutes), get a fan on you if possible, and monitor the situation during your training sessions. If you need a break to cool down, take one. Oxygen will be less available to you, and you will find that in later months of pregnancy, the baby presses upwards on your diaphragm, making it harder to breathe deeply.

nutrition

Good nutrition is essential during pregnancy, but hey, you knew that didn’t you? It is often difficult for female athletes to accept the inevitable weight gain that occurs during pregnancy, but this isn’t a time to diet or be nutritionally stingy. You may notice wild fluctuations in blood sugar (leading to a feeling of “I have to eat NOW!!”), so try to eat at regular intervals and not go more than a couple of hours without a small meal. In the first trimester you may be limited in what you can tolerate, and formerly appealing things may make you feel sick, but this is usually restricted to the first three or four months. You may experience an increase in appetite, including nearly uncontrollable cravings for carbohydrates (mmmm donuts). This does not signify weakness or gluttony on your part; let the hormones do their work and get a balanced diet as best you can. Due diligence requires me to tell you to take in at least 300 kcal over maintenance each day, but if the pregnant women I’ve known are any indication, you’ll be chowing down like someone who just wandered out of the wilderness into a hot-dog-eating contest.

supplementation

Don’t take any supplements during pregnancy or breastfeeding other than a good-quality whey protein and a multivitamin (your doctor may recommend additional vitamin or mineral supplementation). Aside from the lack of knowledge about the safety of creatine during pregnancy, the last thing you want is more water retention. Given the issues with overheating and heart rate, thermogenics and stimulants are contraindicated (this includes caffeine, so cut down on this as much as you can; my experience indicates that the smell of coffee makes many pregnant women sick anyway). Obviously, use of any hormonally-based substances, including prohormones, is a huge no-no at this time. Fish oil has been suggested as desirable supplement for pregnant women, but the research suggests that more study needs to be done before this is a given.

medical supervision and ongoing monitoring

As part of your regular medical checkups, have your doctor advise you on possible changes to your body (e.g. cervical dilation, threatened miscarriage, hypertension etc.) that may require you to modify your program. Ensure that you keep your doctor up-to-date on what kinds of activities you’re engaging in, and whether you notice any worrisome symptoms such as persistent bleeding.

exercise choice

As the pregnancy progresses, avoid exercises which involve lying on the back, or pressing against the stomach (such as chest-supported rows). You may find that you need to modify or eliminate exercises which involve excessive head movement, such as stiff-legged deadlifts, if they cause nausea or dizziness. Avoid prolonged periods of standing. Balance will eventually be a concern, so in the second and third trimester, reduce and eventually eliminate the Olympic lifts and perform demanding overhead lifts while seated (see the section on physioball use below). One of the most typical problems encountered by pregnant women is back pain. Their center of gravity shifts and extra weight is added over nine months. Women tend to slouch the shoulders and arch the lower back to compensate for these changes, which of course leads to discomfort. A strong abdominal column as well as a strong back gained through weight training before pregnancy can alleviate much of this problem, so assistance work geared to this need is helpful. Bodyweight exercises, such as unweighted squats, present a useful alternativeas the pregnancy develops, as do exercises which take some weight off the joints, such as swimming or cycling.

exercising for two

A growing fetus is a greedy little thing (as parents will attest, not much will change in that respect once it’s born, either). The body will adjust its substrate utilization to ensure that the wee tenant gets the best of what you have. Your nutritional needs will change as will your body’s response to exercise. Pregnancy dramatically alters glucose and insulin response to prolonged exercise, as well as blood lipid profiles. These return to normal postpartum. It has been speculated that this represents a glucose conservation mechanism and a protective shunting of energy substrate for fetal use. In other words, physiology dictates that fetus is numero uno when it comes to getting first dibs on the good stuff.

recovery

Be prepared for reduced recovery and adjust your training accordingly. Be aware that some of the modalities you may use for active recovery, such as hot tubs, may be inappropriate during this time. You’ll probably want to do a lot of sleeping anyway.
postpartum urinary incontinenceSorry, squeamish readers, I had to mention this. After giving birth, many women notice problems with mild to moderate urinary incontinence during exertion, such as squatting or deadlifting. Kegel exercises are a must during pregnancy and after delivery. You may find, to your chagrin, that you will occasionally experience some slight laxity in this regard even with careful attention to treatment. Simply plan it into your workouts: avoid caffeine, go to the bathroom before your workout, wear a pad, and remember that there are a lot of other women out there experiencing the same thing. While we’re on the topic of embarrassing things, you may also notice hemorrhoids which are aggravated by lifting. Again, normal and treatable, though unpleasant. Are you starting to comtemplate growing the baby in a jar yet?

training frequency

An interesting finding of recent research on pregnancy is that exercise frequency is a determinant of birth weight (the higher the birth weight, in general, the healthier the baby), and that too much exercise can be as detrimental as too little. Women who exercised more than 5 times weekly and fewer than 2 times weekly were both at risk for having lower birth weight babies (interestingly, intensity did not appear to be as significant a factor as frequency). This finding points to a “happy medium” of 3-4 weekly sessions of structured exercise for pregnant women. In this case I mean 3-4 weekly sessions of training, rather than general activity. Daily activity and movement, in some form, is the ideal.

Other research suggests that a lower volume of exercise in the second and third trimester is associated with better fetoplacental growth (although the mother demonstrates more fat gain rather than lean body mass gain relative to a higher volume of exercise). The more recent ACOG document (2002) argues that daily or near-daily moderate exercise of 30-minute sessions is recommended.

It seems evident that total workload should be reduced as the pregnancy progresses. For most women this is intuitive, since the demands of a growing fetus tend to reduce their desire to go all-out in the gym. Few women have the urge to do a maximal lift while eight months pregnant; the idea of a nice nap is likely more appealing.

However, some athletes feel that they cannot tolerate a reduction in training volume or intensity. For these women, the research gives a clear caution which must be heeded.

whither weight trainers?

A difficulty encountered with the research on pregnancy and exercise is that the majority of studies look at cardiovascular exercise, and will often use endurance athletes as a population or sample,perhaps comparing them to sedentary women. While we can make inferences from this work, we cannot expect that all elements will apply precisely to women who weight train.

Guidelines on weight training are sparse, and hint at using lower intensities by defining appropriate rep ranges (between 15 and 25 reps per set). This appears to indicate a lack of familiarity with structuring weight training programs, as well as the needs of experienced weight trainers for whom such a low intensity may be inadequate. Thus we need to begin to theorize about how best to develop a strength training program based on the evidence we have.

Given concerns about joint laxity, heart rate, oxygen consumption, and overheating, it seems inappropriate to suggest that weight trainers build their program around long sets of lower intensity. Rather, I would think it sensible to take an approach which uses shorter sets combined with a lower intensity, resulting in a similar overall volume. So, for example, let us say that our pregnant trainee normally performs 3 sets of 10 reps in the squat, using a weight which is somewhere around 65-70% of her 1RM. For an experienced trainer this is a relatively low intensity to be using, so we assume that she can continue to use it as long as she is comfortable with it.

However, we might modify her program so that she is performing something like 6 sets of 5 reps each, or even 10 sets of 3 reps, for the same total volume, but changing the demands of each set to reflect the increased need for rest and moderation.

Eventually you might also substitute some machines for certain free weight exercises to reflect challenges to balance (though bear in mind the challenge of joint laxity, and choose machines wisely, avoiding those which require you to exert the most force in the weakest position, such as pec decks).

For example, the bent-over position assumed during a one-arm dumbbell row might produce dizziness and back pain, so an intelligent substitute might be seated cable rows, or even a modification to the free weight exercise which includes a higher support and so less of a forward lean.

Many of these considerations do not come into play until the second or third trimester. Many women have successfully met significant athletic challenges while in their first trimester. In the firsttrimester, the primary concern is usually nausea, dizziness, and blood sugar swings. Attention to hydration and nourishment should = help; sipping at a carb drink (if you can tolerate it) during the = workout can be useful. Training can be mostly normal during this = period. However you should begin to consider decreasing intensity and volume from the fourth or fifth month onwards.
physioball phunA nifty piece of gym equipment which is beginning to be used as a pregnancy accoutrement as well as equipment for labouring women is the swiss ball, aka the physioball, aka the giant vinyl beach ball thingy that “core stability” devotees seem to be into these days. Since these are relatively cheap, it’s not a bad idea to pick one up.

In later months of pregnancy, many women experience significant pelvic pain as the weight of the baby presses down and ligaments stretch. One undignified but useful position which appears to alleviate this pain is getting down on hands and knees and hugging the ball, resting the weight of the upper body on it, and rocking back and
forth if desired.

Bridging exercises with the physioball can help relieve back pain and strengthen torso and hip extensors.

Pregnant women may also find it more comfortable to use the ball in place of a chair or bench while sitting during normal activities (such as desk work or watching TV), as well as during exercise. The squishiness of the ball provides cushioning for increased weight, and the instability of the ball helps with torso mobility and awareness.

Women in later stages of pregnancy can use the ball to help modify common exercises, such as squats. Wall squats with the ball are performed by placing the ball between your back and the wall, and rolling down the wall with it into a squatting position.

Finally, women in labour may find some relief from sitting on the ball during contractions, and rocking back and forth.

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sources

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