Your Third Trimester
The third trimester of your pregnancy brings some significant changes that can be addressed or alleviated by your attention to two specific considerations: postural deviations and mindset.
Postural Deviations
From the beginning of your pregnancy, the hormone relaxin (which causes ligamentous laxity) has been flowing through your body, allowing for essential skeletal shifts that allow for the baby’s growth. The presence of relaxin can also lead to exaggerated shifts as you move through your third trimester. The increased weight will likely cause an anterior pelvic tilt (lordosis), which may lead to prominent low-back pain. The anterior weight shift also occurs at the breasts throughout pregnancy, profoundly more so in the third trimester. This pull adds to increased kyphosis at the cervical and the Kyphosis can pull you out of a neutral spinal position, which may lead to neck and upper-back pain.
Mindset
As your delivery date nears, there's is a tendency to lose focus on your personal health. You must keep in your personal wellbeing is intimately connected to your baby's health.
Continue exercising. It will look and feel different (as you already know) but continued movement and exercise is great. With a naturally reduced venous return during the third trimester, it’s very important for you to keep moving to help stave off edema (commonly found in the ankles). This focus on maintaining movement may also lead to a slightly lower birth weight. “Stopping exercise in late pregnancy tends to produce a larger baby who has more body fat,” explains Dr. Clapp.
Focus on improving core strength. As previously mentioned, most women experience an anterior weight shift during the third trimester, which makes core strength essential for helping to pull the pelvis back into neutral. Focusing on strengthening your core musculature will also help to keep your lumbo-pelvic complex from making shifts, as well. These shifts can lead to pain at the sacroiliac joint and the pubic symphysis.
Reengage the posterior muscular chain. With much of our physical world being anteriorly driven, many of us tend to be over-contracted in our anterior (front side, chest, shoulders) muscular chain. During pregnancy, especially in the third trimester when you are at your largest, this becomes more and more apparent. The muscles of your upper back (mid/lower trapezius and rhomboids) become weakened and elongated, while the muscles of the low back (erector spinae) shorten and tighten in lordosis. Finally, the glutes tend to “shut off,” which means you must rely more heavily on your quadriceps. This disengagement of the glutes also leads to unwanted shifts at the pelvis. Reengaging the posterior chain requires exercises that focus on strengthening the glutes.
Enhance pelvic floor strength (and elasticity). Going into the third trimester, the weight of the baby in utero can drop the pelvic floor up to an inch. Kegel exercises to strengthen the pelvic floor are recommended throughout pregnancy and especially during the third trimester as the pressure is the greatest during this time. Kegel exercises are crucial.
Bottom line, listen to your body. Exercise is recommended BUT if something does not feel right, immediately contact your doctor.
Lastly, balance and coordination is something to always be very aware of during your third trimester. Nearly all of your exercises will be in supported positions.