Indianapolis [email protected]

Exercising Through the Third Trimester

Exercising Through the Third Trimester

Share this Post

If you have been following along, we’ve made it to the third trimester! I hope you have enjoyed these posts and have found them educational. This post covers the third trimester which is defined by week 28 to birth. The third trimester is an exciting time, yet it poses some of its own unique challenges for the mother. At this point in the pregnancy, the mother is in the “home stretch.” New discomfort and trouble sleeping for the mother might be experienced as the baby continues to grow. Low back pain, joint pain, and swelling are all factors that might cause the mother to want to stop working out at this point in the pregnancy. While it might be uncomfortable, it is important to continue to push through and work out during this time because there are many benefits that translate directly into the delivery room and ease the overall process of the delivery. Additionally, other stressors like the last-minute finalization of the nursery and getting everything in order at work before maternity leave might pose other reasons why mothers might not want to keep working out. However, it is so important to make exercise a priority during this time not only for the physical benefits but also for the mental benefits and the relief of stress it can provide. 

Benefits of Exercise on Labor

Studies have revealed that women who exercised during their pregnancy experience easier and faster deliveries (sometimes an average of two hours less!) than mothers who did not exercise. Additionally, studies have shown that 24% of exercising pregnant women had fewer c-sections and less complications than mothers who did not exercise (Clapp, 2012). Women who exercised had shorter hospital stays, needed less operative intervention during labor, and returned to their pre-pregnancy shape quicker than the women who did not exercise (Clapp, 2012). Interestingly, Clapp’s studies reveal that expecting mothers who have worked out the duration of their pregnancy but then stop during the third trimester might have a more challenging birth than those who did not exercise at all (Clapp, 2012). Thus, consistency and commitment to exercise is key! 

Physiological Changes

Skeletal and Posture Changes

At this point in the pregnancy, the mother’s posture has been significantly affected due to the increased weight of the growing baby. Low back pain is present as the growing belly is pulling the body forward. The “duck waddle” begins to occur as the baby is positioned down and pressure is put on the pubic bone. To assuage this discomfort, the feet and legs will want to naturally turn outward. As a result, this new gait will cause tightness and cramping in the glutes and hamstrings due to the constant external rotation of the hips. To combat this, it is important to engage the abdominal muscles to “draw the baby up and in” and be mindful of correct posture. 

Shortness of Breath

Did you know that during pregnancy, the uterus will become 1,000 times its original size?! No wonder it is often hard for women to breathe during this point in their pregnancy. The uterus is pushing against the diaphragm which, in turn, provides less space for the lungs to expand during breathing, causing shortness of breath. However, research has shown that women who exercised during the duration of their pregnancy had an easier time breathing at this point in their pregnancy compared to those who did not exercise. However, even for exercising pregnant mothers, shortness of breath is common, and it is important to take several water breaks during a workout. Be mindful of your breathing and remember to pace yourself to maintain normal breathing patterns.  


Sciatic nerve pain can be experienced during the third trimester. The sciatic nerve starts from the lower back and travels down the legs all the way to the feet. Sciatica brings about a shooting pain or feeling of numbness in the lower back, glutes, and down through the hamstrings. Because the baby is growing, this pain is likely a result of poor alignment, the uterus pressing on the sciatic nerve, external rotation of the hips, or an entrapment of the nerve by the piriformis muscle. Unfortunately, not much can be done to relieve this pain due to the positioning of the baby at this point in the third trimester. When it comes to exercising, to alleviate some of this pain, certain leg exercises that completely stretch the nerve should be avoided. However, there is some good news. Continuous exercise during the first and second trimester of pregnancy, along with healthy eating habits, might help pregnant mothers to avoid sciatica completely or help to lessen the pain in the third trimester! 

Abdominal Separation

Another issue that occurs during the third trimester is abdominal separation (diastatis recti). While the baby continues to grow, it is pushing the abdominal muscles further and further out. If the baby still needs to grow, the abdominal wall will eventually separate once the rectus abdominus has reached its limit of elasticity. This separation generally occurs right down the middle of the abdominals (the linea alba) and the belly button (the umbilicus). While this phenomenon sounds very frightening, it is actually quite common, and exercise can decrease the occurrence and the severity of it. Abdominal exercises focusing on the transverse abdominis (the innermost abdominal muscle) and the pelvic floor muscles will significantly help to assuage the severity of the abdominal separation. However, abdominal exercises that focus on the obliques that have repetitive twisting (i.e. bicycles and Russian twists) should be avoided. Once the baby is born, most abdominal separations will begin to heal on their own. 

Goals of Exercise During the Third Trimester

As you can see, there is a lot going on during the third trimester of pregnancy as the baby is getting closer and closer to its arrival. The main focuses of exercise during this trimester are to work on proper positioning and posture, to continue core strengthening, and to work on balance. In addition, pelvic floor exercises and Kegels should still be incorporated into workouts. If you need a refresher on what these exercises are, refer back to my first blog post found here. Focusing on these key areas during this point in the pregnancy will help the mother to feel more comfortable and stronger which will ultimately help with the delivery of the baby. 

If you would like to learn more about the specific exercises we recommend during the third trimester, please reach out and let’s work together!

Yours in Wellness,



Exercising Through Your Pregnancy

Oh Baby! Fitness Prenatal and Postpartum Training