Family Health Magazine - ACTIVE LIVING
Exercising During Pregnancy
Give your body and your baby a health boost
A woman’s body changes a great deal during pregnancy to create the best environment for her baby to grow. Once, we feared that exercising while pregnant might harm the fetus (unborn baby). Concerns existed about greater risk of miscarriage, early birth, low birth weight, poor pregnancy outcomes and resulting affects on childhood development. However, studies have not supported these fears. In fact, research shows that light to moderate exercise during an uncomplicated pregnancy benefits a woman’s health during pregnancy (see sidebar on page 23). It may help with birth and recovery. Exercise also maintains fitness, helping women feel good about their bodies. Rest assured that once the baby is born, light to moderate exercise will not affect the composition or production of breast milk.
Exercise during pregnancy
Following simple guidelines will help make exercising during your pregnancy safe and enjoyable.
- Before starting or increasing an exercise program, have a thorough medical evaluation done by your doctor.
- If you were active before pregnancy, continue activity during the first trimester but do not increase it.
- If you were inactive, wait until the second trimester to begin a new exercise program.
- Pregnant women can tolerate mild changes in core body temperature with light to moderate exercise. Core body temperature should not rise 1.5 degrees above resting temperature or above 38.9 C degrees during exercise.
- To avoid becoming overheated, check your temperature, avoid exercising in hot environments, and drink enough fluids. Ten glasses of fluid (water, juice or milk) each day is recommended. Have a drink before, during and after exercise.
- Make certain you are getting the appropriate number of calories and monitor your weight gain. Most women require an increase of 300 calories a day in the first and second trimesters. This may increase to 500 extra calories during the third trimester. Canada’s Food Guide to Healthy Eating provides helpful guidelines.
- Dieting to lose weight is not recommended during pregnancy. Talk to your maternity care provider about appropriate weight gain.
- Select a bra that is supportive and fits well to protect your back and breasts during exercise.
- Check for separation of your abdominal muscles. This can be done by lying on your back and slowly raising your head and shoulders off the ground. Press two fingers into your abdomen just below your belly button. You should feel a soft gap between two hard muscles. Measure the space of the gap using your fingers. If the gap is greater than two finger widths, you may have separated abdominal muscles. If you are unsure consult your maternity care provider. During pregnancy, if you suspect abdominal muscle separation, abdominal exercises should be avoided.
- Choose activities you enjoy. Exercising with a partner or group can help. When deciding whether exercise is appropriate during pregnancy, consider the type, frequency, length and intensity.
Reasons to stay active during pregnancy: studies show that pregnant women who exercise are likely to gain the following benefits:
- Decreased risk of developing gestational diabetes (diabetes during pregnancy), high blood pressure and depression
- Prevention of blood clots and varicose veins
- Improved body image and maintained or improved level of physical fitness
- Reduction and prevention of low back pain and joint injury
- Reduced nausea, vomiting, constipation, heart burn and fluid retention
- Reduced problems with passing urine too often or problems holding urine
- Decreased risk of complications during the birth process, including signs of fetal distress, cord entanglement and abnormal heart rate in the baby
- Women who exercise during pregnancy report easier labour and faster recovery after delivery compared to non-exercising women
- After giving birth, exercising women are more likely to return to their pre-pregnancy weight and are less likely to develop postpartum depression.
Choosing the right type of exercise
Certain activities are not appropriate in any stage of pregnancy. This includes any exercise where blunt or penetrating injury to the abdomen is possible. Avoid exposure to too much pressure (such as during scuba diving), too little oxygen, or too much heat. Activities that are high-impact, excessively stretch joints, or require quick changes in motion are not recommended.
Exercising all major muscle groups is important both during and after pregnancy. Strength exercises may be continued or started after the first four months. Women who have previously been strength training can increase by 10 to 15 per cent during the second trimester. Focus on exercises that strengthen the body core, posture and pelvic area. Weights should not be so heavy that you must hold your breath during an exercise.
Recommended activities (low risk)
Activities to avoid
Stationary cycling or spinning
Light weight training
Yoga and Pilates
Court sports (such as
basketball or tennis)
For aerobic conditioning, low-impact or weight-supported activities are preferred over running or high-impact activities. Good activities include stationary bicycling, water running, water aerobics and swimming. Swimming or water aerobics are a good choice since body weight is supported by the floating effect of water. Cool water temperatures help control body temperature. As well, compared to weight-bearing activity, the effort expended feels less. Brisk walking may be a good substitute for running or jogging as pregnancy progresses.
Avoid exercises that require lying on the back, especially after the first four months. This position could lower blood flow to the uterus (womb) and the baby. As well, during pregnancy, abdominal exercises are not recommended if the abdominal muscles are separated. However, following pregnancy, if abdominal muscle separation persists specific exercises can be done to encourage healing. Consult your maternity care provider prior to starting an exercise program.
Remember to warm up before and cool down after exercise. Include range of motion exercises for all joints, including the neck, shoulder, back, arms, hips, knees and ankles. Stretch all major muscle groups, but take care not to overstretch.
Aerobic and strength training activity should be done regularly, allowing enough time to recover between sessions. If you were exercising before pregnancy, continue your regular routine. However, do not increase the frequency until the second trimester. If you did not exercise regularly before pregnancy, wait until after the fourth month of pregnancy to begin. Begin by exercising three times per week, alternating days. You can then progress to a maximum of four to five times per week.
Start with 15 minutes of exercise, as well as a thorough warm up and cool down (at least 5 minutes each). As the pregnancy progresses, you can gradually increase the amount of time. If you did not exercise before pregnancy, keep sessions in under half and hour. If you are used to regular physical activity, 30 to 40 minutes of exercise is appropriate.
Heart Rate Target Zone
||140 - 155 BPM
|20 - 29
||135 - 150 BPM
|30 - 39
||130 - 145 BPM
|Older than 40
||125 - 145 BPM
During pregnancy, avoid exercise routines requiring maximum effort. Use one of these simple methods of estimating exercise intensity.
- Talk test – an exercising mother-to-be should be able to carry on a conversation comfortably when exercising. For many women, this may be the simplest and easiest method of monitoring exercise intensity.
- Range of heart rate for age, modified for pregnancy – the table above shows the safe range of heart beats per minute (BPM) during exercise, based on the mother’s age.
- Rate of perceived exertion (RPE) scale – this scale can be used to decide how difficult you find an exercise. A range of about 12 to 14 (somewhat hard) is appropriate for most pregnant women. Compare your heart rate to how hard you find an activity. The mid-range of your RPE should be at the low end of your heart rate target zone.
Rate of Perceived Exertion (RPE) Scale
|7 Very, very light
|9 Somewhat light
||17 Very hard
|11 Fairly light
||19 Very, very hard
|13 Somewhat hard
From PARmed-X for Pregnancy
Stop exercising and consult your doctor if you experience:
- bleeding or fluid gush from the vagina (birth canal)
- steady and continuing contractions (more than six to eight per hour)
- unexplained pain in the abdomen
- absence of usual baby movement
- sudden swelling of ankles, hands and face
- unexplained fainting, dizziness, headache, vision problems or chest pain
- swelling, pain and redness in the calf
- little weight gain.
Exercise can benefit you at any time, including pregnancy. Most pregnant women can exercise regularly at light to moderate levels without harming themselves or their baby. When exercising, keep the warning signs in mind. If you do experience them, stop exercising and seek medical attention.
For more information
All the recommendations in this article may be found in more detail from:
PARmed-X for Pregnancy
Canadian Society for Exercise Physiology
Click Publications and look under PAR-Q forms
Position Statement on Exercise and Pregnancy
Canadian Academy of Sport and Exercise Medicine
Click Position Statement link under About CASM
While effort is made to reflect accepted medical knowledge and practice, articles in Family Health Online should not be relied upon for the treatment or management of any specified medical problem or concern and Family Health accepts no liability for reliance on the articles. For proper diagnosis and care, you should always consult your family physician promptly. © Copyright 2019, Family Health Magazine, a special publication of the Edmonton Journal, a division of Postmedia Network Inc., 10006 - 101 Street, Edmonton, AB T5J 0S1 [AL_FHa11]