During pregnancy, the body undergoes amazing adaptations essential for childbirth. During this time there are considerable health and wellbeing benefits to being physically active during and after pregnancy. This is true for people who are already active, and those taking their first steps too.

Exercising in water provides a low-impact but high-reward opportunity to be active, that overcomes many of the barriers that may be experienced during pregnancy. Exercising in water can take many forms, such as swimming, aquatic exercise and ai chi (aqua tai chi) and take place in many aquatic spaces (swimming pools, swim spas, lakes and more). Over the last decade, research into aquatic activity during pregnancy has demonstrated its multiple benefits which will be referenced in this article.

Why Water?

Buoyancy

The buoyancy of water creates an experience of weightlessness, especially when submerged in waist-deep water or deeper. This can make aqua exercise easier and more relaxing for pregnant women, particularly if they are experiencing joint or pelvic pain. The buoyancy of water also supports the bump, reducing the weight they carry and strain on your back. Together this means most people can exercise for longer, more frequently and with lower risk of injury in water than on land.

Hydrostatic Pressure

The weight of water pushing against the ribcage encourages deeper and fuller breathing and increases oxygen uptake for both mother and baby. Many pregnant women experience swelling in the feet and ankles, particularly in the last trimester. The pressure of water reduces swelling through naturally increasing blood flow back to the heart.

Viscosity and turbulence

Unlike exercise on land, aqua exercise is low impact and less likely to lead to sore muscles after a session. However, low impact doesn’t mean low intensity: The harder you push in water, the harder water ‘pushes back’, creating self-regulating resistance exercise.

Thermal

Both warm and cool water have been demonstrated to have a therapeutic impact on the body. Warmer waters can soothe aching muscles and have a relaxing effect on mood, while cooler can reduce inflammation and could improve immunity.

The Science of Antenatal Aquatic Activity

The largest and most recent systematic review on aqua exercise (Cancela-Carral et al, 2022) included 17 clinical trials evaluating the impact of aqua exercise on pregnant women. The author concluded that aqua exercise has the positive effect of:

Reduced excessive weight gain

Improved birth weight of new-born

Cognitive benefits: reduced rates of depression, improved sleep, improved overall quality of life, improved body image

Physical benefits: reduced back and pelvic pain, physical fitness, and mobility

Most of the studies included in the review involved aquatic activity 3 times per week for 45-60 minutes per session.

Another systematic review including five studies on the functional effects of aqua exercise in pregnant woman (Santos et al, 2021) also reported that aquatic activity during pregnancy also improves blood pressure in addition to confirming the positive effects on sleep quality, weight control and joint pain. An earlier review (Parker & Smith 2003) also identified the benefits to the fetus as a result of aqua exercise.

Where to exercise in water?

Indoor Swimming Pools – Find thousands of public pools in the UK on Swim England’s Pool Finder.

Outdoor Lidos – are often open between spring to early Autumn at venues across the UK. Take a look at the Swim England Pool Finder or google search for swimming pools near you.

Swim Spas – Swim Spas an ‘infinity pools’ have risen in popularity in since the pandemic. There are more venues will smaller pools on offer and they are still perfect for exercising during and after pregnancy.

Hotel pools – A growing number of hotels also offer memberships and day passes to access their pool and gym facilities. It’s recommended to google search for local hotels around you and investigate if they have a pool on-site.

The Outdoors: rivers, lakes and the sea – There are many benefits to being in the water outdoors. It’s recommended to check the sea water quality on the Surfers Against Sewage interactive map and river water quality on The Rivers Trust website. Additionally, it’s always recommended to enter outdoor water where there are lifeguards present, you can find your nearest lifeguarded beach here.

H²O Considerations

There may be considerable benefits to aquatic activity, but there are some precautions you should take when working out in the water during and after pregnancy.

Pregnancy complications

For most women, exercise is actively encouraged during pregnancy. If you are concerned, or you experience dizziness, pain, or discomfort before or during exercise, stop and contact your GP, midwife or consultant obstetrician.

Stay Hydrated

Even though you might not feel like you are sweating while exercising in the pool, you are. Be sure to hydrate by drinking plenty of water during your workout and throughout the day. You should stop exercising if you feel dizziness, clamminess, or other signs of overheating.

Check in on your temperature

Avoid being in water which drops or raises your core body temperature, like particularly hot thermal waters or extended periods of cold-water exposure. Aquatic exercise in water less than 33 degrees for 45 minutes is accessible and safe (Ravanelli et al, 2018).

Wear Sunscreen

Always wear sunscreen (and think about wearing a hat) if using outdoor pools or aquatic spaces when the sun is shining.

Be active with a buddy

It’s always best to be active with someone else, particularly in pools or outdoor spaces where you would otherwise be solo. Make it social and invite a friend. :)

References

Cancela-Carral J, Blanco B, López-Rodríguez A. (2022). Therapeutic Aquatic Exercise in Pregnancy: A Systematic Review and Meta-Analysis. Journal of Clinical Medicine. 19;11(3):501.

Parker K, Smith S. (2003). Aquatic-Aerobic Exercise as a Means of Stress Reduction during Pregnancy. The Journal of perinatal education, 12(1), 6–17.

Ravanelli N, Casasola W, English T, Edwards K, Jay O. (2018). Heat stress and fetal risk. Environmental limits for exercise and passive heat stress during pregnancy: a systematic review with best evidence synthesis. British Journal of Sports Medicine, 53: 799-805.

Santos B, de Souza C, Santos R, Cordeiro A. (2021). Functional effects of aquatic exercise in pregnant women: a systematic review. Clinical & Biomedical Research. 41. 10.22491/2357-9730.106169.