Physical activity and pregnancy

Despite this, less than 15% of women achieve the minimum recommendation for physical activity during their pregnancy.¹ All women should discuss whether they are suitable to exercise during and after pregnancy with their health care provider.^{1, 2} The following questions will be covered in this blog post:

• What are the benefits of exercise?
• What are the current recommendations?
• What exercise is safe during pregnancy?
• What exercise is unsafe and should be avoided?
• How do I continue exercise through my pregnancy? How do I get started?
• Can all women exercise or are there some conditions which limit what you can do?

The benefits of exercise during pregnancy.

Exercise has positive effects on both mental and physical health. It has been shown to improve self-esteem and general wellbeing.¹ Additionally, it is associated with reduced stress, fatigue, anxiety and depression.^{1, 2, 3} Exercise can improve muscle strength and endurance, as well as cardiovascular function and physical fitness during pregnancy.² It decreases the risk of pregnancy complications including pre-eclampsia, gestational hypertension, gestational diabetes mellitus and newborn complications.^{1, 2, 3} It also helps to reduce the amount of weight put on during pregnancy, and reduces postpartum weight retention.^{1, 2} Exercise results in fewer delivery complications including Caesarean section and instrumental delivery.^{1, 2} Exercise is used as a tool to prevent and manage urinary incontinence and to reduce back and pelvic pain.^{1, 2}

Exercise is not associated with stillbirth, miscarriage, preterm birth, birth defects, neonatal death, induction of labour, birth complications or preterm/prelabour membrane rupture.¹

Physical activity recommendations during and after pregnancy.

For women who are able to participate in exercise, they should accumulate between 150-300 minutes of moderate intensity physical activity each week.^{1, 2} Moderate intensity is often described at an intensity where you are able to talk but not sing.^{1, 2} Exercise should occur over a minimum of three days, but preferably women should be active each day of the week.^{1, 2, 3} The greater the levels of activity, the greater the benefit.^{1, 2} Aerobic exercise is recommended, as well as strength training of major muscle groups twice weekly.^{1, 2} Doing both of these types of training is more beneficial than doing either one or the other.¹ Pelvic floor muscle training is recommended to be performed on a daily basis to reduce the risk of urinary incontinence.^{1, 2, 3} A warm-up and cool-down should be performed.^{1, 2} Particular attention must be placed on maintaining adequate fluid intake and nutrition.^{1, 2}, ³ Additionally, women should exercise in safe environments that are not at the extremes of temperature or that are likely to increase risk of falls.^{1, 2, 3}

Safe options for exercise.

• Aerobic exercise: walking, jogging, cycling, swimming.^{1, 2, 3}
• Strengthening exercise using bodyweight, resistance bands or light weights.^{1, 2, 3}
• Pool-based exercise.²
• Pelvic floor exercises.^{1, 2}
• Pregnancy specific exercise classes eg: yoga, pilates.¹
• Stretching.¹

Physical activity that should be avoided during pregnancy includes:

• Activities involving significant changes in pressure eg: scuba diving, sky diving.^{1, 2}
• Exercise that involves physical contact or increases the risk of falling eg: rugby, horse riding, skiing, gymnastics.^{1, 2, 3}
• Maximal lifting.^{1, 2}
• Exercise at altitudes higher than 2000 metres.² Women may be able to exercise at a moderate intensity between 2000-2500 metres if properly acclimatised.¹
• Specific abdominal strengthening during pregnancy for those with diastasis recti.¹
• Excessive Valsalva manoeuvre (breath-holding) especially if associated with light-headidness.¹
• Physical activity in high humidity/heat.^{1, 2, 3}
• Exercise lying flat on ones back from the second trimester, particularly if causing symptoms such as dizziness and nausea.^{1, 2}
• Avoid rapidly changing between postures from the second trimester.³

How to exercise during pregnancy.

For women who were relatively inactive prior to pregnancy, participating in physical activity is recommended. They should begin gradually at a lower intensity. They can increase the duration and intensity of exercise slowly throughout pregnancy.¹ For active women, exercise can continue throughout pregnancy, until such time where it becomes uncomfortable to do so.¹ Elite athletes should seek advice from an obstetric care provider to discuss the benefits and risks of exercise.^{1, 2} Physical and physiological changes that occur during pregnancy will remain for 4-6 weeks after birth.² Women should seek guidance from their health care provider as to when they can recommence activity. Return to high impact activity or activity that stresses the pelvic floor, should occur gradually.^{1, 2}

Precautions and contraindications to exercise.

Not all women are able to participate in regular exercise. For women who are unable to, they should continue with usual activities of daily living.¹ Women with any of the following contraindications should not participate in strenuous exercise.^{1, 2}

• Ruptured membranes or signs of premature labour
• Unexplained persistent vaginal bleeding
• Placenta previa after 28 weeks
• Pre-eclampsia
• Incompetent cervix
• Intrauterine growth restriction
• High-order multiple pregnancy eg: triplets
• Uncontrolled type 1 diabetes, uncontrolled hypertension or uncontrolled thyroid disease
• Other serious cardiovascular, respiratory or systemic disorder

For some women, discussion needs to be had around the benefits and risks of exercise. Women with the following should have this conversation with their obstetric care provider.^{1, 2, 3}

• Recurrent pregnancy loss
• History of spontaneous preterm birth
• Gestational hypertension
• Symptomatic anaemia
• Malnutrition
• Eating disorder or malnutrition
• Twin pregnancy after the 28^th week
• Mild/moderate cardiovascular or respiratory disease
• Other significant medical conditions
• Extreme overweight/obesity (BMI >30)

Exercise should be stopped if pregnant women experience any of the following symptoms. They should seek advice from a healthcare professional before recommencing activity.^{1, 2, 3}

• Severe chest pain
• Regular and painful uterine contractions
• Vaginal bleeding
• Persistent loss of fluid from the vagina indicating rupture of the membranes
• Persistent dizziness or faintness that does not resolve on rest
• Persistent excessive shortness of breath that does not resolve on rest
• Abdominal pain
• Decreased foetal movements
• Sudden oedematous swelling

It is important that you seek advice from an obstetric care provider before commencing exercise both during and after pregnancy. Physiotherapy can assist in helping choose the right exercise for you, and teach you how to progress exercise appropriately. Here at Advanced Physiotherapy, we run supervised pre and post-natal Pilates classes. Contact us today if you are interested in getting started!

References

1. Mottola MF, Davenport MH, Ruchat S-M et al. Canadian guideline for physical activity throughout pregnancy. BMJ Sports Med. 2018;52:1339-1346.
2. Exercise in pregnancy and the postpartum period. Sports Medicine Australia. 2016.
3. Lewis E. Exercise in pregnancy. Australian Family Physician. 2014;43(8):541-542.