Pregnancy and fitness

Planning the best exercise approach pre and post natal is a challenge. Here we try to guide you towards the best fit for you.

These days, the words pregnancy and fitness are far more synonymous than they used to be. For the most part, women who exercise regularly prior to pregnancy, look to carry that fitness through to childbirth. Or, once pregnant, they decide to increase their focus on fitness in preparation for the challenge of looking after children.

Exercise undertaken during the lead up to childbirth can help ease the aches and strains of pregnancy, as well as pave the way for an easier birth. Sustained fitness during pregnancy can also help with a quicker return to pre-pregnancy weight.

For those reasons, and many more, it is important to have an educated, systematic approach to fitness during pregnancy.

Unfortunately, many myths surrounding exercise and pregnancy exist, which can discourage pregnant women from exercising as hard as they would actually like to. This article aims to summarise the changes that pregnant women go through and what effect these changes have on the ability to exercise. It will highlight the benefits of exercise and discuss which type of exercise most pregnant women can carry out with confidence.

First off, what are the risks to exercising during pregnancy?

1. There is an increased risk of injury, which is due to both postural changes resulting from the growing uterus (changing the woman’s centre of gravity) and changes in joint laxity from the release of the hormone relaxin. Studies have shown that these risks can be minimized through good exercise prescription (Heckman & Sassard, 1994, Musculoskeletal considerations in pregnancy. Journal of Bone and Joint Surgery).

2. Due to the increased rate of carbohydrate metabolism, there is a small risk for the mother and foetus of excessively lowering their blood sugar. This risk, however, can be managed easily by ensuring adequate nutrition.

3. There is an increase in heat production during pregnancy and a maternal temperature above 39.2 degrees may lead to the foetus overheating. However, a recent study (Jones 1985, Thermoregulation during aerobic exercise in pregnancy. Obstetrics and Gynaecology) was able to reassure women that the re-direction of blood flow to the skin leads to adequate heat transfer away from the core, as long as women exercised at a self-imposed moderate rate.

4. To avoid general over-exertion some medical professionals recommend for the women’s heart rate to stay below 140 beats per minute. However there is not much evidence available to support this claim. Therefore, the American College of Sport Medicine recommends that exercise should not be monitored via the women’s heart rate but via the perceived rate of exertion. In other words, a pregnant women can get out of breath whilst exercising, as long as she is still able to talk.

Below is a list from Mantle, Haslam & Barton (2004, Physiotherapy in Obstetrics and Gynaecology) on Contra-indications to vigorous exercise during pregnancy. In short, unless a pregnant women suffers from any of these risk factors, she can enjoy the numerous benefits of exercise (Baker, Pregnancy and Fitness, 2013).

Absolute Contraindications to Exercise:

• Cardiovascular Disease; Acute Infection; A history of spontaneous miscarriage; A history of preterm labour; Multiple Pregnancy; Vaginal bleeding; Ruptured Membranes; Pregnancy induced hypertension; Incompetent Cervix; Suspected foetal distress; Pulmonary Embolism or thrombophlebitis; Chronic hypertension, and Uncontrolled diabetes type 1

Relative Contraindications to Exercise:

• Women unused to high levels of exertion; Anaemia or sickle cell disease; Thyroid disease; Diabetes –gentle exercise is recommended!; Extreme obesity or extreme low weight, and Breech in third trimester

What are the benefits of exercise during pregnancy?

The benefits are numerous, and include (but are not limited to):

1. Reduction in back pain

2. Improved posture

3. Reduction in leg cramps, swelling, constipation, varicose veins and haemorrhoids

4. Improved calcium re-absorption and a reduction in risk of osteoporosis

5. Improved sleep

6. Enhanced mental wellbeing and self-confidence

7. Confidence in ability to deal with labour

8. Reduced risk of gestational diabetes

9. Reduced risk of high blood pressure

10. Quicker recovery time after birth

11. Faster return to pre-pregnancy weight

12. Shorter labours

The most important message is: during a normal pregnancy, fit and healthy women can continue almost everything they did pre-pregnancy (apart from the exercises mentioned at the end of this article). Unfit pregnant women can gradually get used to many forms of exercise during pregnancy, as long as they listen to their body and increase the amount of exercise gradually.

Exercises which are good for pregnant women:

1. Core stability exercises such as four-point kneeling, reverse bridges on a ball, sitting on a ball and lifting one leg off the ground

2. Pelvic floor exercises

3. In the gym: treadmill walking or running depending on pre-pregnancy fitness level, stationary bike, rowing machine (depending on size of tummy), stepper, cross-trainer

4. Walking or running outdoors depending on pre-pregnancy fitness levels, avoid uneven ground as ligaments are lax and ankle injuries become more likely

5. Swimming, aqua aerobics

6. Resistance training on machines or with free weights is safe as long as the woman feels comfortable, continues relaxed breathing throughout and maintains good body alignment

7. Body conditioning classes, as long as there is a good teacher who can demonstrate adaptations depending on fitness levels and stage of pregnancy. For example: a pregnant woman may do sit ups in week 0-12, pelvic tilts in week 12-20, all four superman in week 20-28 and all four pin-points in week 28-40.

8. A Pilates class at a normal level is fine until about week 20 (beginners do beginner, advanced women do advanced classes), and then specialised pregnancy Pilates thereafter

9. The same as the above applies to Yoga

In addition to more formal exercise, it is a good idea to start training your deep core and pelvic floor muscles while pregnant to prepare them for the post-natal period. Over the course of the pregnancy the core and pelvic floor muscles are gradually stretched and there is potential for various types of trauma during labour and delivery.

These factors often make it extremely difficult to re-train these muscles after delivery as the neural pathways that link your brain and the muscles have become sluggish. It is therefore a good idea to work on keeping the neural pathways working well by continuing with exercises to work the core and pelvic floor throughout pregnancy – even if your muscles don’t seem to be co-operating!! This should make it much easier to ‘find’ and re-train the muscles after delivery.

Pelvic floor tips:

• Make sure to keep breathing throughout

• Make sure the pelvic floor is working internally and that the gluteal (bottom) muscles are not gripping or sucking in the abdominal muscles therefore cheating

Exercises and sports to avoid during pregnancy

These include:

• Deep-sea diving

• White-water rafting

• Contact sports

• Skiing

• Water skiing

• Sky diving

• Exercise at altitude (if not used to it)

• Surfing

• Gymnastics

• Ice skating (risk of falling)

• Volleyball/ Basketball

• Squash

• Tennis (if vigorous)

• Horse-back riding (due to risk of falling from horse)

• Anything that feels wrong or uncomfortable

Ref: Baker, Pregnancy and Fitness, 2013.

As with any major life and body change, there are many factors to be considered. However, for the most part, continued, appropriate exercise is incredibly beneficial both during pregnancy and after childbirth. Unsubstantiated myths should not deter pregnant women from reaching and maintaining adequate fitness during pregnancy.

Of course, it’s always a good idea to chat to a professional to discuss the relevant benefits and any concerns before embarking on an exercise programme during pregnancy.