Musculoskeletal changes during pregnancy

34 weeks pregnant :-) Not too much longer until nenem will be here!! Since my last blog I have cut my mileage down a little and am now doing around 60 miles per week. However this past week I have been feeling some discomfort in my right sacroiliac (SI) joint. The same place I had a lot of trouble with when running after Lucas was born. I went to see my chiropractor Dr Lance McClintock as I soon as I noticed and have been getting rehab done. I do not feel anything walking or running but when standing from sitting I have some discomfort over the SI joint. Even though it is not sore during running I have switched to the pool until I feel no pain just in case running was causing my SI joints to get out of place. I may just stick to the pool until after the baby is born just to be safe. I need to be very cautious with the SI joint as I don't want to get an injury from this or something that will affect my running after the baby comes. Also I have found swimming and aqua running to be great and I can work a little harder as I don't feel the weight of the baby.

In this post I will share my research on the musculoskeletal changes that occur during pregnancy. Definitely all these changes are leading to my discomfort in the SI joint. But with treatment from Dr McClintock the SI joint is getting better each day.

Musculoskeletal changes
During pregnancy changes occur that have an effect on the musculoskeletal system. These are outlined below:

1) Weight gain
The weight gained during pregnancy can dramatically increase the amount of stress placed across joints like the hips and knees by as much as 100% during running and other weight bearing activities. These forces in turn might be the reason for joints that become painful or are at risk of injury. (Artal and O'Tolle 2003, Br J Sports Med 37:6-12).

2) Postural Changes
The changing pregnant woman's body and increase in weight cause big changes in posture shown in the image below. Abdominal distention causes the pelvis to tip forward (anterior pelvic tilt), and a decrease in abdominal strength as the muscles are so stretched. These two factors combined with the increase in weight requires a realignment of the curvature in the spine.  The woman's center of gravity moves forward which can cause lumbar lordosis (increase in the normal lumbosacral curve). To compensate this realignment the upper back and neck (cervicodorsal region) also change in curvature to allow balance to be maintained. This can cause back pain and a higher risk of losing balance or falling.
(Lowdermilk D, Perry S 2006, Maternity Nursing, Ch 8: Anatomy and physiology of pregnancy, pdf file).

3) Muscular imbalances
To compensate for the changes in posture during pregnancy, some muscle groups are required to work
more in order to keep the body in an upright position and some less. This causes muscular imbalances. As the pregnancy progresses the muscles working too hard will shorten and become very tight. The opposing muscles are required to work less and in turn become weaker and loose. See table below:

Muscles that tighten		Muscles that weaken and overstretch
Hip flexors		Buttocks (gluteals)
Front of thighs (rectus femoris)		Back of thighs (hamstrings)
Chest muscles (pectorals)		Abdominal muscles
Internal Rotators and elevators of shoulders: rhomboids, levator scapulae and upper fibers of trapezius		Mid and lower fibers of the trapezius in the upper back
		Pelvic floor muscles
		External rotators of shoulders
		Ribcage muscles

 (http://www.befitmom.com/physiological_adaptations.html)

In order to help prevent or reduce the impact of these muscle imbalances you should stretch the muscles that are tight, and strengthen the muscles that are weaker and looser.

4) Laxity of Ligaments
The laxity of the ligaments is thought to be occur because of increasing levels of the hormones relaxin and oestrogen needed during pregnancy and childbirth. Relaxin is released in order to relax the muscles, ligaments and joints to allow space for the baby and during delivery. Most of the effects caused by relaxin are prevalent in the pelvic area. Because the joints become more relaxed it can lead to a decrease in stability and or pain in the area (Artal and O'Tolle 2003, Br J Sports Med 37:6-12).
To help maintain pelvic stability I am seeing my chiropractor Dr McClintock, stretching the area, rolling my hips and surrounding areas on a foam roller and doing hip exercises.

I will finish this post with my updated weight gain chart and a few photos from the past few weeks and the growing baby bump :-)

Weight gain chart 

Enjoying the aquarium

Park time - 32 weeks pregnant

33 weeks pregnant :-)

Tio Henrique and Tia Mariana came to visit from Brasil :-)

Exploring trails at Houston arboretum and nature centre

Park time with Tio Henrique

Lucas in training :-)

               Better watch out Bolt!! Lucas has been training :-)

HAPPY RUNNING EVERYONE!!

Below are some references and articles I found interesting while researching this topic:

1) R Artal, M O'Toole 2003. Guidelines of the American College of Obstetrics and Gynaecologists for exercise during pregnancy and the postpartum period, Br J Sports Med 37:6-12

Link to this paper: http://bjsm.bmj.com/content/37/1/6.long

2) Lowdermilk D, Perry S 2006, Maternity Nurinsg ed 7, ch 8 Anatomy and physiology of pregnancy, Elsevier Heath Sciences, pdf file

Link to this book: http://www.coursewareobjects.com/objects/evolve/E2/book_pages/lowdermilk/pdfs/208-230_CH08_Lowdermilk.qxd.pdf

6 months pregnant!!! Question and Answer time

6 months pregnant!!!! Where have the months gone? The second pregnancy seems to be going by so much faster than it did with Lucas. I guess having a 2 year old to run after does not give you the time to think about the pregnancy as much. I meant to write more posts along the way and post some photos of the growing bump. I will do so from now on :-)

During the pregnancy but more so in the last couple of weeks I have been asked a lot about my running during pregnancy. Some of these questions are below:
Are you still running?
How many miles are you running?
Why do you continue to run?
Did your doctor approve running/exercise while pregnant and have you done research on the topic?
Do you monitor your heart rate while running?
Do you have any guidelines that you follow while running?
Should I also run while pregnant?

I thought it would be nice to answer these questions in my blog.

Are you still running?
I am still running and hopefully if all goes well I can run until the end. With Lucas I decided to stop running about 2 weeks before delivery because I was getting pain in my foot. I swtiched to the pool and did swimming and aqua jogging after this point.

How many miles are you running?
Currently around 70 miles (112km) per week. Some days I run twice and on others run once in the morning and then swim in the afternoon. All of my running is just jogging now. For the first 5 months I was adding in some short tempos and interval work but over the last month have cut these out as it started to feel uncomfortable going at a faster pace.

Why do you continue to run?
There are so many reasons why I am still running.
* Maintain fitness and retain muscle tone. Hopefully this will help with a quicker return to competitive running.
* Prevent excessive weight gain.
* Combat fatigue and stress. Sounds strange but after running I always feel more energized and less stressed.
* Boost my mood. Whenever I don't run I am never myself. My husband will tell you that when I cant exercise my mood is not always the best.
* Looking at the research helps strengthen my decision to run through pregnancy. It is well documented that exercise positively affects pregnancy, labor, and possibly pregnancy outcome. Exercise improves cardiovascular fitness and overall well-being. It can help to reduce the occurrence of gestational diabetes. Some research has shown that moderate intense exercise throughout pregnancy can lessen the time of delivery and complications. Also the fetus of the exercising mother seems to tolerate the stresses of labor better than the non-exercising mother (Sterfield B. Physical activity and pregnancy outcome: Review and recommendations. Sports Medicine 23:33-47, 1997)

Did your doctor approve running/exercise while pregnant and have you done research on the topic?
Yes and yes. My Dr. not only supported my decision to keep running but encouraged it. Her rationale was that before getting pregnanat I ran around 100-110 miles per week. My body is used to the miles and the movement. I have been doing a lot of reading on the subject of running and exercising while pregnant. There is not a whole lot on just running exclusively but a good amount of studies on exercise in general. One article I particularly liked titled 'Physical Activity During Pregnancy' was published in the Journal of Pregnancy and outlines how society has changed on their views of exercise and pregnancy. A summary of this article is below. Plus at the end of this blog I have put all of the references and links that I used so you can refer to them if interested.

Opinions on pregnancy and physical activity have changed dramatically over the years. For a long time physical activity was seen as harmful and detrimental to a healthy pregnancy and not supported by society or medical professionals. It was thought that exercise could harm the fetus and lead to a preterm baby or restrict the growth of the fetus and cause infants that were too small. In 1985, the American College of Obstetricians and Gynaecologists (ACOG) published the first recommendations for exercising while pregnant. These included the following:

a) Maternal heart rate should not exceed 140 beats per minute

b) Maternal core temperature should not exceed 100.4 degrees F (38 degrees C)

c) Strenuous activities should not exceed 15 minutes in duration
d) Women who did not exercise before pregnancy were advised not to start physical activity while pregnant.
A lot of research was done on the topic between 1980 and 1990 that supported the need for the recommendations to be updated as many studies proved the safety of exercise while pregnant. This lead to the ACOG changing their guidelines. In 1994 they removed the restriction on exercise duration and heart rate. Physical activity could be performed but not to exhaustion. Then in 2002 the ACOG started to promote physical activity showing the numerous health benefits for all women, not only those who performed physical activity before pregnancy (as long as given approval from the doctor). The most recent ACOG guidelines (published in 2002 and reaffirmed again in 2009) recommend 30 minutes or more of moderate exercise on most, if not all days of the week. In 2008 the United States Department of Health and Human Services (DHHS) published the first ever Physical Activity Guidelines for Pregnant woman. This publication stated that all pregnant woman are recommended to perform at least 150 minutes of physical activity done at moderate intensity (with doctors approval) (Smith K, Campbell C, Hindawi Publishing Corporation, Journal of Pregnancy, 2012, Physical Activity During Pregnancy: Impact of Applying Different Physical Activity Guidelines,Volume 2013, Article ID 165617, 9 pages)

Do you monitor your heart rate while running?

No. My doctor believes (and I agree with her) that how you feel before, during and after a workout is a far more effective way to assess the health, safety and quality of the workout than the heart rate response. My doctor and many other health professionals are recommending pregnant woman follow the Borg Rating of Perceived Exertion (RPE) to monitor the effort of exercise during pregnancy. RPE is an effective way to measure the intensity level of the physical activity you are performing. The scale is based on how hard you feel your body is working. This basis comes from the feelings you experience during exercise including an increase in breathing, sweating, muscle tiredness and heart rate. Even though it is a subjective evaluation, it has been shown that the exertion rating that a person gives is a good indicator of the actual heart rate during exercise. Pregnant women are normally advised to stay within the 12-14 range on the borg scale. (Borg, 1998 as referenced by the Centres for Disease Control and Prevention - Perceived exertion). A table showing the borg scale is below:

Do you follow any guidelines while running and pregnant?
Yes. After reading many scholarly articles related to this issue and talking with my doctor I do stick to some guidelines.

1) Listen to your body.
There are days when I feel great and I will go a little further and faster and then there are days I feel really bad and only make it 30 minutes with walking in between. I do not monitor my heart rate as explained above but use the Borg scale. I am never running to the point of exhaustion or where I am too much out of breath. Pushing yourself to the limit forces your body to use up oxygen that should be going to your baby.

2) Avoid overheating and dehydration.
When summer hits here in Houston (which will be soon) I will have to be even more careful about running and monitoring how I am feeling. It gets so hot here even early in the morning that I may have to do some on the treadmill. This is because if your core temperature gets too high it could cause problems with the baby like spina bifida. Also the risk of dehydration becomes much greater in the high humidity which can lead to premature contractions (netdoctor.co.uk).

3) Run without a watch sometimes
I do not run with my Garmin watch anymore and sometimes without a watch altogeher. I just run how I feel each day. After having such an intense and structured programme leading up to world champs it has been nice just to run how I feel and when I want. However with the spring marathon season and track season starting up I can feel the urge to want to train and compete coming back :-) Which is a good thing. I will be that much more hungry and determined when I come back after the birth (hoping everything goes smoothly).

4) Watch for any signs signalling I should stop running:
Warning sins to terminate exercise while pregnant:
* Vaginal bleeding
* Dizziness
* Headache
* Chest pain
* Muscle weakness
* Major calf pain or swelling
* Preterm labour
* Decreased fetal movement
* Amniotic fluid leakage
Source: Artal and O'Tolle 2003, Br J Sports Med 37:6-12

Should I also run while pregnant?
This depends on a lot of variables:
1) Did you run before you got pregnant? I would definitley not encourage someone to start running while pregnant if they have not run much in the past. Your body would not be used to the motion and impact. Instead I would recommend starting with walking or swimming or other forms of low impact exercise.  The American College of Sports Medicine have suggested that pregnant woman par take in physical activity on most days of the week if not all. They recommend at least 30 minutes of physical activity performed at a moderate intensity. For those hoping to maintain higher levels of fitness there research has shown that this will occur by doing 20-60 minutes of higher intensity exercise sessions on 3-5 days a week (Artal and O'Tolle 2003, Br J Sports Med 37:6-12). 


2) Do you have any conditions that would put the baby at risk by running or exercising? There are some conditions during pregnancy that may limit the amount of exercise you can safely do. The best advice is to talk with your doctor before starting any new exercise while pregnant. Some of the health factors are poorly controlled Type 1 diabetes, a history of two or more miscarriages, carrying twins, persistent heavy bleeding, heavy smoking and history of extremely sedentary lifestyle. Other reasons are a background of premature labour, anemia, heart disease, restrictive lung disease, morbid obesity, extremely underweight (BMI under 12) and chronic bronchitis (Artal and O'Tolle 2003, Br J Sports Med 37:6-12). 

Sorry that this blog got long. I hope that you enjoyed reading. I will finish with some photos of the growing baby bump and my weight chart. The weight gain chart is comparing my first pregnancy with this pregnancy. With this pregnancy I decided to track my weight before getting pregnant as I was advised by my doctor that I needed to put on some weight in order to get my menstrual cycle back to make getting pregnant easier. It seems for me this always happens when I am between 115lb-120lb. 

Weight chart comparing my first and second pregnancy

5 month baby bump :-) Lucas is very excited!!!

6 month baby bump :-)

Soon to be big brother giving a hug :-)

Next blog I will write about how the body changes during pregnancy and what issues this can cause related to running.

Below is a list of articles and links that I found interesting while researching this topic.

1) R Artal, M O'Toole 2003, Guidelines of the American College of Obstetrics and Gynaecologists for exercise during pregnancy and the postpartum period, Br J Sports Med 37:6-12. 
Link to this paper: http://bjsm.bmj.com/content/37/1/6.long

2) Borg Scale of perceived exertion:
http://www.cdc.gov/physicalactivity/everyone/measuring/exertion.html

3) History of physical activity guidelines for pregnant woman:
Smith K, Campbell C 2012, Physical Activity During Pregnancy: Impact of Applying Different Physical Activity Guidelines, Journal of Pregnancy 2013; 165617
Link to this paper: http://www.hindawi.com/journals/jp/2013/165617/

4) Benefits of exercise while pregnant:
Sterfield B 1997. Physical activity and pregnancy outcome: Review and recommendations, Sports Medicine 23:33-47


Happy Running Everyone!!!