Training Considerations During Pregnancy: Part 1 Introduction & Safety Considerations

Whilst pregnancy can be a fantastic and rewarding experience for many mothers as they prepare to bring a new life into the world, the potential for danger and complications cannot be disregarded. This is especially true when the mother is undertaking an exercise regime as discomfort, loss of function, injury and complications involving both the mother and the foetus can arise if the training is not carefully controlled.

In this series of articles, we examine four major aspects that a trainer should consider when dealing with a pregnant mother. These considerations should all be taken into account in order to achieve the best possible outcome.

1. Exercise Programming Considerations
2. Common Anatomical Considerations
3. Medical and Physiological Considerations
4. Exercise Selection Considerations

Whilst exploring these considerations, the following factors should form the basis for any decisions made as all will impact on the mother’s ability and safety:

Stage of Pregnancy
The stage of the pregnancy will have a profound effect on the type of exercise selected as well as the intensity and duration of the program. The stage of pregnancy affects multiple factors for exercise considerations – for example, balance, hormonal issues and safety of mother and child.

Potential for Injury
Whilst devising a program and supervising the mother the trainer should be aware that there are many factors specific to the pregnant mother that have the potential to cause injury. Changes in the centre of mass of the mother, potential changes in force application and the absorption capacities of the mother’s joints, neural factors and the hormonal impact on the mother’s ligaments are all crucial to consider.

Exercise Experience of the Mother
As with any client, experience is a primary factor in determining the approach the trainer should take. The type of exercises selected and the intensity of these exercises will clearly depend on how long and how well the mother has trained prior to pregnancy.

Expectations of the Mother
Again, as with any client, the trainer must establish what the goals of the mother are and take these into account in order to devise individualised programs. It is important that the trainer designs a program that allows the mother to achieve her goals whilst minimising any potential harm to her or her baby.

Level of Comfort During Exercise for the Mother
Each woman is different and thus will respond differently to the pregnancy and to any exercise. The trainer must establish the limit at which the mother can comfortably complete any exercise, and likewise, ensure these limits are not exceeded to ensure the continued safety of the mother and her unborn child.

As a trainer develops a program for an expectant mother it is also important to consider certain physiological issues impacted by pregnancy:

Heart Rate May Not Be an Accurate Indicator of Intensity
When writing any exercise program for pregnant mothers, cardiovascular endurance is a priority. As such, it is essential that the trainer can monitor the client’s intensity to ensure optimal stimulus to the system is applied to allow development without risk. As a result it is important to note that, unlike with most clients participating in cardiovascular endurance programs, heart rate is not an appropriate measurement of intensity for a pregnant woman. This is due in part to increases in sub-maximal heart rate and the possible blunting of the nervous system to exercise in late gestation. As a result it is advisable to utilise RPE as a measure instead.

Exercise May Add to the Feeling of Fatigue
This is largely due to dilutional anaemia, which is caused by an increase of blood volume and a limited increase in haemoglobin. This hypoglycemic effect of pregnancy normally occurs during prolonged or intense exercise or prolonged fasting and thus may increase feelings of fatigue. Prolonged exercise may cause increases in maternal temperature and may reverse gradient.

Additional Factors
There additional factors are to be considered when developing a program for a pregnant woman. These are generally incidental or secondary effects caused by primary exercise selections:
• Increase in maternal temperature
• Circulating stress hormones
• Ensuring adequate caloric expenditure
• Biomechanical stress
• Effects on the foetus such as hyperthermia, trauma and decreased nutritional availability

Take a read of the second part of the series: Exercise program considerations while pregnant