People are often unaware just how beneficial exercise and physical activity can be when it comes to specific conditions, and pregnancy is definitely no exception!
Mothers who are normally very active before getting pregnant want to continue this lifestyle, and for those who are normally less active, exercising could help in numerous ways and even contribute to a faster and easier delivery.
While safety precautions should of course be addressed, exercising is a viable option and should be encouraged for any pregnant woman without absolute contraindications.
What are the safety considerations of pregnancy and exercise?
Unless you are already an active person who has been cleared for exercise, permission from your physician should be obtained before venturing into a physical program, especially while pregnant.
While programming an exercise routine for pregnancy, intensity is the name of the game. Moderate intensity should be the end goal for most pregnancies. While fitness may increase during an exercise program while pregnant, the main thought should be slowing down the negative effects of the inactivity compared to pre-pregnancy.
Previously sedentary women are encouraged to start exercise, as long as it is a slow, gradual progression into a program. Women who are already active should not exceed pre-pregnancy intensity, but continue with activities that are familiar to them, which is a key point in understanding the variances of programs and activities from person to person.
Some exercises may be acceptable for one person but are a risk for another. This concept would encourage hands-on training that completely involves a qualified individual. Another resource that can be used is the Physical Activity Readiness Medical Examination form (PARmed-X) for pregnancy. This can be used as a screening tool to ascertain the risk of an individual starting a program.
Absolute contraindications. These are certain conditions that need to be resolved if possible before it becomes safe to exercise. These include any significant hemodynamic heart or restrictive lung disease, pregnancy specific conditions such as incompetent cervix or cerclage, placenta previa past 26 weeks of gestation, being pregnant with twins, triplets, etc., pregnancy induced hypertension, premature labor, second and third trimester bleeding, or ruptured membranes.
Relative contraindications. These will need to be monitored during exercise duration and discussed to make sure they do not become a serious issue. They do not necessarily mean that exercise cannot be an option.
Relative contraindications include: poorly controlled weight (underweight or obesity), hypertension, bronchitis, severe anaemia, history of sedentary lifestyle or any orthopaedic issues. Additionally, exercise should be terminated if shortness of breath (dyspnea) before exercise is observed, or if you experience chest pain, vaginal bleeding, decreased fetal movement or calf pain and swelling which could be indicative of thrombophlebitis or swelling of a vein due to a clot.
With exercise, certain movements should also be avoided, specifically the Valsalva manoeuvre, or holding your breath to create intra-abdominal pressure during a movement, which acutely spikes blood pressure.
After 16 weeks, The American College of Sports Medicine (ACSM) also recommends eliminating activity in the supine, or any position on the back, as this could cause venous obstruction and decreased blood flow, as well as isometric contractions3.
It can be debated however, that a low intensity isometric contraction may not affect every pregnant woman the same way due to differences in fitness levels. As previously stated, unless an activity involving an isometric contraction specifically alerts you to any contraindication, you can continue to perform activities that are familiar to your exercise routine.
Isometrics and Pregnancy
The underlying issue with isometrics is that during any muscular contraction, blood flow is interrupted and causes a buildup of pressure through the circulatory system. As isometric contractions are held for a time period, this gradual build-up could cause a temporary, yet significant, spike in blood pressure which should be avoided in pregnant women.
If you have any history of hypertensive tendencies, it’s better to be safe than compromise any aspect of your pregnancy and therefore to avoid this type of contraction. In saying this, under the supervision of a qualified health professional, modified isometric exercises such as planks, wall sits or partial squats may be effective and safe.
Start with short contraction times, perhaps 10-15 seconds and make a conscious effort to breathe deeply and evenly throughout the length of exercise. A personal recommendation would be to not progress past 30 seconds, but rather increase the sets, or times the exercise is performed if greater difficulty is needed and no adverse side effects observed.
Remember, you know your body better than any health professional. If ANY exercise or movement causes more than slight muscular discomfort or alerts you to anything related to the above mentioned contraindications, make your voice heard and the training can be adjusted accordingly.
As long as these guidelines are followed and safety is used, exercise positively impacts pregnancy in a number of ways.
Many Benefits Including Faster Labor!
A study published in the Journal of Strength and Conditioning Research stated that exercise decreased the risk of excess weight gain, gestational diabetes, hypertension and therefore pre-eclampsia in pregnant women and showed that an exercise program strengthening the muscles of the core, back and around the pelvis specifically (using an exercise ball), decreased labor times and increased outcomes.
Focusing on the rhomboids, latissimus dorsi, posterior deltoid, trapezius and other posterior muscles based around the cervical and thoracic region may aid in compensating for the increased abdomen and chest size during pregnancy1. Additionally, focusing on the muscles around the femoral acetabular joint (hamstrings, quadriceps, adductors, abductors, glutes, etc.) may also assist in easing the labor as all of these muscles play a role during birth1.
So what does this mean?
Basically, stronger muscles and better cardiorespiratory fitness (CRF) may relate to a more efficient labor and ease the pregnancy. Additionally, as previously stated, exercise has been shown to decrease some of both relative and absolute contraindications which therefore would decrease the risk of the overall pregnancy.
The goal for working out when pregnant is starting slow, and gradually increasing time rather than intensity.
General recommendations according to ACSM are three to four days per week for a total of 150 minutes of moderate intensity exercise4. Aerobic activities that use the whole body, and that are catered to any discomforts, can be used to increase CRF, which has been linked to a lower risk of low back pain which is common to see with pregnant women3.
Activities such as varying speeds of walking, stationary biking or stair climbing can be used to increase muscular endurance and CRF. Swimming is also a valuable option as it decreases stress on the joints and back, but also allows for a way to train muscular endurance and CRF while negating the risk of falling due to balance issues caused by a shift in one’s center of gravity due to increased abdomen size.
As heat regulation can also be an issue for women who are pregnant, swimming effectively eliminates that risk as well1.
For resistance training, bands or weight machines are preferred, as instability is caused by both increased joint laxity due to hormonal changes and, once again, changes in one’s center of gravity. High repetition (12-15 reps) with a moderately intense resistance can be worked up to in two to three sets.
Flexibility is a component that should be in every well-rounded exercise program and pregnancy is no exception.
Stretching should be incorporated after a workout, during the cool down. Take care to not stretch past the point of mild discomfort and focus on major muscle groups that may aid in decreasing back pain or other discomforts. Due to the increased joint laxity, is important to stretch only to a point of mild discomfort and no more3.
In Part 2 we will look at a variety of specific exercises and a sample workout.
Connect here with WatchFit Expert Jon Kilian
Martens, D., Hernandez, B., Strickland, G., & Boatwright, D. (2006). Pregnancy and Exercise: Physiological Changes and Effects on the Mother and Fetus. Strength and Conditioning Journal, 78-82.
Wing, C., & Stannard, A. (2016). Pregnancy and Exercise Guidelines: Fifty Years Makes a Difference. ACSM’s Health & Fitness Journal(March/April), 4-6. doi:10.1249/FIT.0000000000000183
Bushman, B. (2012). Wouldn’t You Like to Know: Pregnancy and Exercise. ACSM’s Health and Fitness Journal, 16(3), 4-6. doi:10.1249/01.FIT.0000414744.03074.f8
ACSM’s Guidelines for Exercise Testing and Prescription. (2014). Baltimore: Lippincott Williams & Wilkins.
Fournier, D., Feeney, G., & Mathieu, M.-E. (2017). Outcomes of Exercise Training Following the Use of a Birthing Ball During Pregnancy and Delivery. The Journal of Strength & Conditioning Research, 1941-1947. doi:10.1519/JSC.0000000000001672