Mom’s in Motion: Water fitness during pregnancy.

The aquatic environment offers the pregnant exerciser so many reasons to jump in! One study examined 44 pregnant women who participated in two, 45-minute aquatic exercise sessions per week for six weeks. The researchers reported that “regular engagement in aquatic exercise is associated with improvements in positive feeling states and reductions in negative feeling states and fatigue for women during pregnancy.”

The aquatic environment offers freedom from most of the general discomforts of land based exercise during pregnancy, including increased body temperature, impact to joints and irritation to the low back and spine. Exercise professionals should utilize the available research and take advantage of the opportunity to use the water to have a positive influence on the exercising lives of women before, during and after pregnancy.

Weight Gain during Pregnancy

• If you are normal weight before pregnancy, gain 25 to 35 pounds during pregnancy.
• If you are overweight before pregnancy, gain 15 to 25 pounds during pregnancy.
• If you are underweight before pregnancy, gain 28 to 40 pounds during pregnancy (depending on your pre-pregnancy weight).

However, research has demonstrated that this additional weight is frequently not lost in the postpartum period. Even as little as 8 to 10 additional pounds of unnecessary weight can put a woman at increased risk for degenerative diseases, including coronary artery disease, diabetes, obesity and depression. As a result, there exists a damaging impact on a woman’s overall health.

Cardiovascular Exercise Recommendations During Pregnancy
In January 2002, medical experts from the esteemed American College of Obstetricians and Gynecologists (ACOG), published recommendations that healthy pregnant women who have no obstetric or medical problems should engage in at least 30-minutes of moderate-intensity exercise on most, if not all days of the week during pregnancy. The benefits to exercise during pregnancy are significant and include;

1) reductions in the risk of developing gestational diabetes (especially in women with a BMI of 33 or higher)
2) a reduction in the risk of developing pregnancy induced hypertension, also known as PIH
3) fewer obstetric interventions
4) a reduction in the active stage of labor (the time from 4 cm -10 cm. dilation)
5), the need to perform C-Sections may be lower in women who exercise during their pregnancies.

Exercise during pregnancy is also associated with a reduction in common complaints inherent during a healthy pregnancy. Pregnant exercisers experience increased energy, improved sleep, and an enhanced self image. Exercising during pregnancy will also offer the opportunity for a quicker return to pre-pregnancy weight, with the likelihood of continuing exercise post-partum. There are also benefits to the unborn infants. Babies born to exercising mothers have lower body fat levels at birth, which may possibly decrease their cardiovascular risk profile as adults. They are also less cranky, have a lower incidence of infant colic and demonstrate greater scores in oral language and motor areas.

The right exercise intensity
Therefore, in order to promote positive, long-term lifestyle changes in pregnant women, cardiovascular exercise should be the foundation of the exercise program. The frequency should be daily, and the duration 30-minutes of moderate-intensity, but how best to monitor that intensity?

Early and late in pregnancy there is an increase in resting heart rate. Therefore using heart rate formulas adopted from the non-pregnant population is inappropriate in the pregnant population. The often quoted 1984 ACOG Guidelines that recommend keeping the heart rate below 140 beats per minute is still an unfortunate but consistent piece of advice some pregnant women hear and abide by. Although not the current recommendation, it is still a frequently quoted statement by health care professionals. The revised 1994 ACOG guidelines are the most current to date regarding intensity recommendations, and suggest modifying the intensity of exercise using “maternal symptoms” as the guide. This may be the equivalent of using the rating of perceived exertion (RPE). For example, on a 10 point scale, one being rest and 10 extreme exhaustion, she might find exercise between the levels 3 – 5 allow for full cardiovascular benefit at an intensity that corresponds with moderate-intensity exercise.

Get in the Water
In addition to the general benefits of cardiovascular exercise, the aquatic environment offers its own unique benefits to pregnant exercisers. While water and land workouts are quite similar with respect to caloric expenditure and fat burning, the pregnant participant will maintain a lower heart rate in the water. She will also stay cooler and experience a wonderful, floating feeling due to the property of water called buoyancy. The buoyancy effect of the water aids pregnant exercisers by gently lifting the weight of the body upward, thus relieving the stress on the spine, hips and other joints. This is a welcome benefit because this “lift” effect feels very freeing, allowing for a comfortable workout. Buoyancy also reduces the impact shock to the body during exercise, again creating feelings of effortlessness and simplicity during exercise.

Additionally, the water is a terrific conductor of heat and continually cools the body during exercise. Typically, water exercise temperature is generally comfortable between 80 and 88 degrees Fahrenheit. Because this temperature is lower than the body’s normal core temperature, water exercise offers the pregnant participant an opportunity to maintain a lower core body temperature as compared to land, which can be a concern for pregnant participants.

The water also offers exercisers another wonderful tool, and that’s constant resistance. Instead of gravity as resistance, water exercisers have the dynamic resistive force of water. Being in the pool is like being in a giant, liquid weight room. As the participant pushes against the water, the water pushes back. This requires her to apply more force to the water in order to move it, as opposed to the same movement out of the water.

In addition to the water’s resistance, hydrostatic pressure aids the pregnant exerciser by reducing gravitational pull of blood to the lower extremities. The hydrostatic pressure reduces swelling - a wonderful benefit for pregnant women who experience edema. Aquatic exercise has the comparable effect of wearing support hose while exercising on a treadmill. Both the water’s pressure and the muscle contractions associated with exercise help to decrease a pregnant participant’s incidence of varicose veins and hemorrhoids.

Safety First
It is critical that ALL prenatal populations obtain a clearance from their physician prior to beginning any exercise program. Postnatal participants also should obtain a physician’s clearance prior to starting back up with their fitness programming after a pregnancy. A physician’s clearance is required to rule out absolute contraindications to exercise during pregnancy. Prenatal exercisers should be familiar with the absolute and relative contraindications associated with exercise during pregnancy, as recommended by ACOG. A complete list of these contraindications can be found on the ACOG web site.

Hydration is also extremely important for pregnant exercisers. Instructors cannot overemphasize the importance of hydration, both to cool core body temperature and to reduce the risk of dehydration-related complications.

The water invites pregnant exercisers of all age groups, fitness and skill levels to participate in aerobic activity, taking advantage of the benefits that it offers. All it takes is a quality, support bathing suit, appropriate footwear for water exercise, a physician’s clearance, and a willing participant. So jump in – the water’s great!

References
1. “ACOG releases new guidelines on exercise: 30 minutes per day in pregnancy.” Goldman, E.L. Ob/Gyn News; Jan 15, 2002 2. “Changes in Feeling States Following Aquatic Exercise During Pregnancy.” Lox C.L.,Treasure, D.C. Journal of Applied Social Psychology; Vol. 30 pp 518. March 2000. 3. “The Pregnant Exerciser: An argument for Exercise as a Means to Support Pregnancy.” Jeffreys, R. ACSM’s Certified News. Vol. 15; Issue 4. July/August/September, 2005. 5. Mom’s In Motion Pre/Post Natal Exercise Specialty Certification manual. Kooperman, S., Casey, J. SCW Fitness Education, 2005.