10/08/2018 by By Jennifer Earnest, PT, MPT, B.Sc. (Hons) Kin., Registered Physiotherapist
Exercise & Pregnancy
If you’ve been into Bayshore Physical Therapy over the past few months, I’m sure you’ve noticed that I am pregnant with my first child! I consider myself to be a fairly active person, and made it my goal to try to keep up with being active throughout my pregnancy as much as possible. I thought I would take my own knowledge and research I have performed to use for my own personal pregnancy exercise routine and share it with everybody. I will also provide some anecdotal stories about my pregnancy exercise routine throughout this blog!
Doctors previously used more caution in encouraging exercise during pregnancy, but more and more research is supporting the clear benefits for both mom and baby. The American College of Obstetricians and Gynecologists promotes regular exercise for its overall health benefits when pregnant. Specifically, research has found the following benefits to exercise during pregnancy:
- Babies born to active moms have healthier hearts and are less likely to become obese themselves
- Moms-to-be who exercise may have an easier birth and faster recovery afterwards
- Exercising when pregnant may help control weight gain, prevent depression, boost the cardiovascular system, improve circulation and posture, increase muscular strength, relieve muscle aches and cramps, reduce digestive problems like constipation, and prevent urinary incontinence
- There is suggestion for a possible role of exercise in the prevention and management of gestational diabetes
From my personal experience, (especially in the first trimester when I was feeling a bit nauseous), I found that even if I was able to get on my treadmill and go for a brisk 20 minute walk, I felt much more energized and less sick to my stomach afterwards! That being said, I definitely had days where I felt either way too tired or just too nauseous to do any activity. My general conclusion was let your body be your guide to exercise, and respect what it is telling you.
***It is extremely important that the overall health, obstetric, and medical risks are reviewed with your family doctor or midwife before beginning an exercise program when you are pregnant.
The American College of Obstetricians and Gynecologists suggest the following are ABSOLUTE CONTRAINDITIONS to aerobic exercise during pregnancy:
- Heamodynamically significant heart disease
- Restrictive lung disease
- Incompetent cervix
- Multiple gestation (twins, triplets, etc) at risk for premature labour
- Persistent 2nd or 3rd trimester bleeding
- Placenta previa after 26 weeks gestation
- Premature labour with current pregnancy
- Ruptured membranes
- Pregnancy-induced hypertension
Additionally, the following are considered RELATIVE CONTRAINDICATIONS:
- Severe anemia (decreased red blood cells)
- Unevaluated maternal cardiac arrhythmia
- Chronic bronchitis
- Poorly controlled type 1 diabetes
- Extreme morbid obesity or extreme underweight (BMI < 12)
- History of extreme sedentary lifestyle
- Intrauterine growth restrictions in current pregnancy
- Poorly controlled hypertension/pre-eclampsia
- Orthopedic limitations
- Poorly controlled seizure disorder
- Poorly controlled thyroid disease
- Heavy smoker
If certain symptoms or conditions develop during pregnancy, exercising needs to be stopped immediately until medically cleared. Stop and call your doctor or midwife immediately if any of the following occur, as these symptoms are possible medical emergencies:
- Vaginal bleeding
- Shortness of breath before exertion, or increased shortness of breath during exercise
- Dizziness or a sensation of feeling faint
- Chest pain
- Muscle weakness
- Calf pain or swelling
- Uterine contractions
- Decreased fetal movement
- Amniotic fluid leakage
Suggested (Basic) Exercise Prescription
Type of Exercise
Aerobic exercise can include any activity that uses large muscle groups in a continuous rhythm. This can include walking, jogging, dancing, swimming, cycling, rowing, and skipping. It is important to be aware that some activities carry more risk than others. This includes activities that increase the risk of falls or those that cause excessive joint stress, or any type of contact sports. Additionally, after the first trimester, it is recommended that exercises performed on your back are avoided as much as possible, as this position may decrease blood flow to the uterus. Moms-to-be should avoid exercising in hot, humid environments, whether indoors or outdoors, and it is important to stay hydrated whenever exercising.
Resistance training, including weightlifting and flexibility exercises, such as yoga and pilates are also encouraged. Keeping muscles strong throughout pregnancy may help to ease typical aches and pains experienced during pregnancy. If engaging in weightlifting, be sure not to lift heavy – stick with weight that you can lift comfortably for 10-15 repetitions, for 3 sets. Also, avoid any jerky movements – pregnancy loosens ligaments that support joints, which makes them more prone to injury.
My personal exercise program throughout my pregnancy has involved a combination of aerobic exercise on my treadmill, and moderate weightlifting. For my cardio, initially in my first trimester and part of my second trimester, I was able to continue jogging/running at a slightly slower pace than prior to becoming pregnant. As my belly started to grow, I personally found running became uncomfortable, so I substituted running for brisk uphill walking on my treadmill instead. Regarding my strength training, initially I was able to continue with my typical weightlifting exercises, which involved all major muscle groups, performing 3 sets of all exercises for 12-15 repetitions. As my pregnancy has progressed, the weights I am lifting have decreased slightly, and I find I am doing more resistance exercises that simply involve my body weight only.
There are several suggested ways to monitor exercise intensity when pregnancy. In short – don’t overdo it! – keep the intensity to a moderate level, especially in the first trimester. Overexertion can be dangerous to both mom and baby.
- You can monitor your heart-rate. Suggested pregnancy-adjusted target heart rate zones for women aged 20-29=135-155 bpm, women aged 30-39=125-145 bpm. You can wear a heart rate monitor or check your heart rate regularly during exercise.
- Rate of perceived exertion – this is a good alternative to heart rate monitoring. For moderate exercise, RPE should be 12-14 (somewhat hard) on a scale of 6-20.
- Subjectively, you can consider moderate intensity exercise to be at a pace where you can maintain a conversation without feeling overly winded (talk test).
Note that there is no established safe upper level of exercise intensity. However, women who were regular exercisers prior to pregnancy and who have uncomplicated, healthy pregnancies, should be able to engage in moderate-to-high intensity exercise programs (e.g. running, aerobics) without any adverse effects.
While I do have a heart-rate monitor at home, I find the RPE scale or talk test are the easiest ways to monitor my exercise intensity. Again, I have found as my pregnancy progressed, the overall intensity of my exercise has declined slightly (e.g. walking with a little less incline on the treadmill or reducing my walking speed a little bit as required). Again, this also varies day-to-day. On days where I feel more fatigued, my exercise intensity is reduced overall compared to days where I don’t feel tired.
Current recommendations for non-pregnant women for exercise frequency are an accumulation of 30 mins/day on most, if not all, days of the week. In the absence of any medial or obstetric complications, pregnant women are typically able to continue with these same recommendations.
It is important to note that pregnancy is not the time to significantly increase physical fitness. Even women who have had a high level of fitness prior to becoming pregnant need to use caution when engaging in higher levels of fitness activities. Additionally, all women should expect their overall fitness level to decline somewhat as their pregnancy progresses.
My goal throughout my pregnancy has been to perform some type of exercise 3-4 days per week. I will be the first to admit that I definitely have weeks where I’m not as diligent with working out as I would like. Like I mentioned before, in the first trimester I had days where I just didn’t feel well enough to do any activity, and of course there are days that are just too busy where I couldn’t fit in a workout. On average, I have maintained an exercise program 3-4 days per week, involving anywhere from 25-30 minutes of aerobic exercise, and 15-30 minutes of resistance exercise.
- Pregnancy isn’t and should not be a state of confinement! Pregnant women with uncomplicated pregnancies should be encouraged to continue and engage in regular, moderate intensity physical activity.
- The overall health, obstetric, and medical risks should be assessed before a pregnant woman is prescribed an exercise program.
- Regardless of previous fitness level, there are some contraindications that may develop in pregnant women that preclude them from continuing to exercise safely during pregnancy.
- All active pregnant women should be examined periodically to assess the effects of their exercise programs on the developing baby, so adjustments can be made if necessary.
- Despite the fact that pregnancy is associated with profound anatomical and physiological changes, exercise has minimal risks and multiple confirmed benefits for most women.
Artal R and O’Toole M. Guidelines of the American College of Obstetrics and Gynecologists for exercise during pregnancy and the postpartum period. British Journal of Sports Medicine, 2003, 37: 6-12.
Nascimento, Simony L, et. al. Physical exercise during pregnancy: a systematic review. Current Opinion in Obstetrics and Gynecology, 2012, 24(6): 387-394.