Pregnancy & An Introduction to Exercise Considerations
With education, training, and life experiences I have learned that pregnancy is a period in a woman’s life that is characterized by an extreme amount of physical, mental, and emotional stress. The female body is incredible and resilient, and this holds true during this time when there are physiological changes happening in every system in the female body. With our training on the human body and review of the research of the pregnant and postpartum woman, physical therapists are able to help throughout each trimester and even into what is known as the “fourth trimester”.
Changes that occur throughout the body
Cardiovascular system:
- Increase in blood volume
- Increase in resting heart rate, cardiac output
- Increase in blood flow to uterus, kidneys, and skin
What this means for Physical Therapy and exercise?
Monitoring your heart rate during exercises, using the talk test or the Borg Perceived Exertion test to stay at a moderate level instead of using heart rate targets for training. Heart rate will spike at the beginning of exercise, so intensity needs to change and be monitored.
This also means in the second trimester we should avoid laying the back for exercises as the baby places stress and pressure on the descending venous and arterial blood flow.
Respiratory system:
- Increase in oxygen, around 30%
- Increase in edema in the upper respiratory tract
- Hormones progesterone and relaxin cause the ligaments around the sternum to relax and then the diaphragm elevates
What this means for Physical Therapy and exercise?
Deeps breaths are harder, chest widens, and we need to encourage diaphragmatic breathing
Endocrine system:
- Growth Hormone is replaced with placenta growth hormone
- Decrease in TSH and increase in HCG in the 1st Trimester
- Enter a state of hypercortisolism, 3 times the amount
What this means for Physical Therapy and exercise?
Pregnancy is a stressful situation and exercise is more stress on the body, however, good stress as our body adapts to this stress. 10-20% drop in fasting glucose due to increase in glucose utilization (but can be exact opposite with gestational diabetes.)
Nutritional system:
- First Trimester: No changes in need
- Second Trimester: 240 extra calories needed*
- Third Trimester: 450 extra calories needed*
** May be different if energy expenditure changes
Gastrointestinal system:
- Delayed gastric transit times and emptying
- Nausea and vomiting
- Heartburn in the 2nd and 3rd Trimester
Haematological system:
- Increase in plasma by 30-50%
- Increase in red blood cells 18-25%
- Hematocrit decreases
- Blood volume increases by week 7 and peaks at 30-34 weeks
Musculoskeletal system:
- Increase in body mass
- Abdominal muscles lengthen
- Increase in lumbar lordosis
- Increase in pelvic width
- Center of gravity shifts anteriorly
What this means for Physical Therapy and exercise?
This means a lot! We will help to screen you during your pregnancy to assess what exercises are best for you to continue doing as your pregnancy progresses. We will work with you to teach you proper movement mechanics, exercise modifications, and help you proper breathing mechanics with core stabilization that is safe to continue throughout pregnancy and into the postpartum period.
Virtually all women experience some sort of discomfort and 25% of woman have discomfort so severe it is at least temporarily disabling.
All women without absolute contraindications should be active during their pregnancy, even those who are current inactive and those who have gestational diabetes.
Pregnancy is not a disability, but it should be treated like an injury with proper modifications.
Don’t worry, we will consistently communicate with you and your other health care providers and always refer back to our education and research to make sure you are safe to exercise.
Here is a quick reference of what we consider contraindications and precautions:
There are many benefits of exercise during pregnancy:
- Decrease in maternal weight gain
- Decrease in gestational diabetes and high blood pressure
- Decrease in postpartum depression
- Decrease in time during 1st and 2nd stages of labor
- Stronger core and pelvic floor muscles
One of the more commonly known and talked about musculoskeletal impairments that can happen during pregnancy is diastasis recti. Diastasis recti occurs when there is an opening at the level of, above, or below the umbilicus. This is a tearing or separation of your abdominal muscles along the linea alba, which is where 3 of your abdominal muscles come together. This is actually NORMAL into the late 2nd and 3rd trimesters. A Physical Therapist can assess your abdominal muscles to see if you have any separation. After delivery we can help work to close this separation.