Updated: Dec 13, 2021
For women of varying levels of activity from an elite athlete to a hobby jogger or weekend warrior, there are a lot of adaptations to the female body when going through a pregnancy that they should be aware of.
There are many things to consider when participating in sports to protect the child and the mother. You would be advised to quit high-risk sports like basketball, soccer, pole vaulting, or equestrian. Sports where there is a greater risk of collisions falls, or quick decelerations can affect the health of the mother or child. On the other hand, with sports like running or golf, the athlete is at a lower risk of injury because contact and falling are not as common. Exercise is encouraged early in the pregnancy to keep a healthy lifestyle, improve posture, decrease discomfort, and is known to help prevent gestational diabetes.
A physiological adaptation with pregnancy is that the expanding uterus and enlarging breasts change the center of gravity. This causes the athlete to compensate for the change in their posture and gait (step length, step width, and support time) as well as a greater lordotic curve of the lumbar spine and anterior rotation of the pelvis, which slowly adapts to be able to deliver the child at the end of the 9 months. Most of these changes affect the athlete after the first trimester.
A Cardiovascular adaptation with pregnancies affects the heart and the lungs. To be able to deliver blood and nutrients to the child through the placenta the heart has to work overtime. The pregnant woman’s resting heart rate will increase 15-20 beats per minute. The dimensions of the ventricles of the heart increase in diameter, which causes the stroke volume (amount of blood ejected from the left ventricle to the body) to increase by 10% at the end of the first trimester. This ensures that the mother is getting adequate oxygen and nutrients to her child as well as the rest of her body.
The women can also experience Increases in respiratory sensitivity to carbon dioxide while in the early stages of the pregnancy. This will protect the child from rising levels of carbon dioxide with activity. Respiratory distress is more common later in pregnancy, at rest, and with exertion. The change in resting oxygen uptake is due to change in body mass causing a decline in oxygen uptake with each trimester. Because of this adaptation, the women’s perception of respiratory effort is reduced because of adaptations that reduce airway resistance, preserve breathing mechanics and minimize efforts of ventilation.
It would also be encouraged not to do any exercises on your back or spend a lot of time on your back. This is because the weight of the uterus can compress on a vital vessel called the Inferior Vena Cava. This is responsible for bringing blood back to your heart and can lead to hypotension in 10-20% of women.
Another thing to consider with a pregnant athlete is the core body temperature and environmental factors. Strenuous activities like running a marathon or exercising in high temperatures can be a risk factor for fetal abnormalities. Keeping the body core temperature below 103 degrees is crucial. Exercise at 60-70% of your VO2 max in a controlled environment for less than an hour is advised as it is not enough to raise your core body temperature.
Preconception care is important to consider by making sure that you are able to care for both you and your child in the best way and prevent any adverse effects. Make sure if you are pregnant to speak to your doctor to monitor training, nutrition, resistance training, and symptoms.
For pregnant athletes, it is important to stay hydrated. As your body works to cool you and your baby, you’ll likely start sweating earlier and faster. This means you’ll lose fluids more quickly, leading to dehydration. Pregnant runners should drink half of their body weight per day in ounces. A 160-pound athlete should drink 80 ounces. It is recommended to drink before and after exercise and eat frequently. Drink something high in electrolytes like a REZ. It is all-natural, plant-based, immune-supporting, and filled with vitamins and minerals to keep your body strong and healthy.