Maintaining an exercise regime throughout pregnancy is becoming increasingly important for Mothers to be. Despite the willingness to engage in physical activity, Women often report confusion regarding clear guidelines for exercise prescription, duration, and parameters throughout the duration of their pregnancy. As Physiotherapists we work closely with Women throughout their antenatal and postnatal journey from a musculoskeletal and pelvic health perspective. Throughout these timeframes, ensuring appropriate prescription is vital for safety and to instil the confidence needed to participate in a training program.
Exercise Guidelines
The following guidelines have been extrapolated from the Royal Australian and New Zealand College of Obstetricians and Gynaecologists and Sports Medicine Australia 2020 recommendations.
- Those without contraindications for exercise should participate in regular aerobic and strength conditioning exercise during pregnancy
- There is no evidence that regular exercise during an uncomplicated pregnancy is detrimental to mother or foetus
- Assessment of medical and obstetric risks should be undertaken to identify potential contraindications to exercise for the pregnant woman prior to commencing an exercise program
- Exercise prescription must accommodate for the physiological adaptations to pregnancy and consider the gestation at which it is prescribed
What type of training and how often?
In the absence of contraindications to exercise, women should be engaging in 150-300 minutes of activity each week. This equates to 30-60 minutes of moderate intensity exercise most days of the week. Women who are overweight/obese or previously sedentary may be advised to start with modified activity durations.
So how does one determine what moderate intensity exercise is? There are a number of different measures to utilise dependent on the setting. For independent tracking, the rating of perceived exertion scale as shown can be a great gauge. Here the activity would be reported as ‘somewhat hard’ or being able to maintain conversation throughout.
Your treating clinician may also utilise a heart rate monitor for a measure consistent with the guideline of 60-80% of maximal aerobic capacity.
The type of exercise should include an aerobic and strength conditioning component. Aerobic training should be guided by preference and includes activities such as walking, running, swimming, stationary bike or cycling. These utilise large groups and maintain a sustained elevation in heart rate. Strength training should occur twice per week with bodyweight, resistance bands or weights. Parameters around sets and repetitions of exercise will vary dependent on previous activity levels and should be discussed with your treating team. It is important to note that lying flat on the back for strength training should not occur beyond the first trimester. In regard to aerobic exercise, women should avoid lying on the back for prolonged periods of time during the second and third trimester.
The type and intensity of the exercise are clearly outlined to ensure that there is no risk to thermoregulatory capacity. The core temperature should not be greater than 39 degrees nor should there be a rapid increase in core temperature by 1.5 degrees from baseline. Consideration should therefore be taken with the environment as below:
- 25 degrees with 45% humidity for 35mins of land-based activity
- Water immersion at <33.4 degrees for 45mins
- Sitting in hot bath 40 degrees for 20mins
Exercises to avoid
- Exercises with high abdominal pressure eg. Weightlifting
- Contact sports
- Sports with projectiles or striking
- Sports with risk of falling or demands of extreme balance
- Hight intensity training at altitudes or with significant changes in pressure
- Exercises in a supine position
Contraindications to exercise participation
Your Physiotherapist, Obstetrician/Gynaecologist, GP, and Midwife all play a role in screening for potential and absolute contraindications to exercise participation during pregnancy.
Conditions including but not exclusive to:
- Incomplete cervix
- Placenta praevia after 28 weeks
- Recurrent pregnancy loss or previous spontaneous abortion
- Growth restricted foetus
- High multiples
- Ruptured membranes
- Signs of premature labour
- Hypertensive disorders
- Anaemia
- Pre-eclampsia
- Persistent bleeding
Will be cleared prior to engagement in exercise. Some of these conditions listed however are potential contraindications only which may not restrict all activity level at the discretion of the treating team.
Benefits
The maintenance of an exercise regime throughout pregnancy has significant benefits for both mother and foetus. These include reduction in Gestational Diabetes Mellitus, Gestational Hypertension and Pre-Eclampsia risk by 38, 39 and 41 % respectively. This not only reduces the likelihood of cardiovascular health implications with the mother post-partum but also adverse health outcomes for the child. The benefits also extend beyond cardiovascular disease and include a reduced risk of excessive maternal weight gain, depressive symptoms, and poor body image perception.
