Exercise During Pregnancy


The American College of Obstetricians and Gynecologists give pregnant women very conservative recommendations for exercise during pregnancy. The general impression is that exercise can be dangerous. Many researchers, however, including Dr. James Clapp, a renowned researcher in the field of exercise during pregnancy, says that a pregnant woman’s body is very similar to an athlete’s and is well prepared for the demands of strenuous exercise.

A pregnant woman has expanded blood volume, larger heart chambers, greater blood volume per heartbeat, and faster transfer of oxygen to tissues. Athletes also exhibit these differences. Fit women are able to adjust to pregnancy faster than women who don’t exercise because their bodies are already half way there.

Pregnancy Exercise Myths

  • Exercise should not cause the heart rate to exceed 140 beats per minute.
  • Pregnant women should refrain from any supine exercise (lying on the back) after the first trimester.
  • Running and bouncing exercises are not safe for the fetus due to the jarring impact.
  • Bouncing exercises can weaken the pelvic floor.
  • Exercising longer than 20 minutes at a time will overheat the baby and take needed oxygen and nutrients away from the placenta.
  • Abdominal exercises of any kind should be avoided after the first trimester.

Benefits to the Mother and Baby

  • Reduces aches and pains – Exercise improves posture by strengthening the back and abs. These muscles are absolutely requisite for carrying a 12 + pound tummy comfortably.
  • Improves circulation – Improved circulation confers several benefits to a pregnant woman. It can help prevent constipation and prevent cramps common in pregnancy. The improved blood flow can also help to reduce swelling in the legs and the resulting varicose veins.
  • Prevents wear and tear on the joints – Exercise helps to stabilize the joints and offset the effect of the pregnancy hormone relaxin which relaxes the ligaments that support the joints.
  • Boosts immune system – Dr. Clapp’s research team observed that the incidence of colds, flus, sinusitis, and bronchitis is lower in the pregnant women who exercise.
  • Lowers gestational diabetes risk by 27% – Exercise helps to keep blood sugar even.
  • Helps your body snap back quicker – Maintaining a high level of fitness helps moms get back to a regular exercise routine faster than non-exercising moms, hence staying toned, and keeping weight in check.
  • Reduces mood swings and stress – Exercise boosts serotonin and endorphins which makes us feel happier.
  • Reduces fatigue – Pregnant women often feel tired. While sometimes it seems hard to get moving, exercise actually gives the pregnant woman an energy boost. Exercising pregnant women have more energy in general and are more able to tolerate the stresses of pregnancy and care of an infant.
  • Improves sleep – Active, pregnant women often report better sleep. However, it is best not to exercise too near to bed time as it can contribute to insomnia.
  • Reduces morning sickness – While feeling nauseous can make it difficult to get moving, many women report that they feel less queasy after a workout.
  • Keeps weight in check – Cr. Clapp showed that women who exercise all the way through till the end of their pregnancy gain on average 8 lbs less than their sedentary counterparts.
  • Improves body image – Being fit helps a woman feel better about herself, especially when her big belly is making her feel a little less than sexy.
  • Faster and easier delivery – Having a baby requires strength and stamina. What better way to prepare for this than by being strong and fit. Studies have also shown that pregnant women who exercise need fewer pain killers, probably because their endorphins, which are natural pain killers, are higher.
  • Become a better athlete – Clapp found that women who train all the way through their pregnancies “increase their maximum aerobic capacity by 5 to 10 percent.” This is true despite the fact that their pregnancy training levels were actually lower during pregnancy than before pregnancy.
  • Smaller babies to birth – Babies of exercising moms are less fat but still as long and robust as heavier babies born to moms who don’t exercise.
  • Leaner children – These leaner babies will be leaner all the way up to, at least, their fifth birthday.
  • Stronger fetal cardiovascular system – Researchers from the Kansas City University of Medicine and Biosciences found that the fetus is more than just a passive observer of mother’s exercise routine. Fetuses of mothers who exercise have stronger hearts much like the exerciser herself does.
  • Improved tolerance to the stress of delivery – Studies have shown that babies born to exercising moms experience less stress at the time of delivery.
  • Fewer infant problems – The newborns of exercising mothers are reported to have less colic, sleep through the night earlier, and are easier to care for in general.
  • The placenta grows faster – This means more nutrients and oxygen for the baby. If no other reason gets you moving, I would think this one should!

There is a whole lot more about exercise in my book!

« »


  1. As I learned about my pregnancy with my daughter when I was already 8 weeks along I had raced in early pregnancy (very tough cross country running). Actually, I took the pregnancy test because my results didn´t match my expectations :-). It didn´t hurt the baby and she turned out to be strong and healthy! I slowed down consideraby and siwtched to the elliptical, weight training on machines, fitness classes because I wanted to be safe. I probably would stick more to my current routine if I was pregnant again because I know it won´t harm the baby. However, staying active has helped me to recover extremely fast from my c-section and be at pre-pregnancy weight right after delivery (okay, as soon as I considered stepping on a scale, my be a week or so after :-)). Since then, my routine has changed considerably and I do a lot more weight lifting and I´d try to continue if I was pregnant again! Do you feel safer using machines? I think squats would be great for pregnant women (with or without weights). Did you check Cassandra Forsythe`s fir pregnancy interview series? It is definitely the best stuff you can find on the internet! Keep on working out! I wish you all the best!

    • When I was pregnant with Evelyn I was alternating fast sprints with distance (still hadn’t heard of over exercising back then). But before I even knew I was pregnant I just kind of quit. I thought it was pretty weird that I didn’t feel like running all of a sudden. I had run for years, but I took it as a cue that my body needed something else so I started taking long day walks and hikes. I cracked up when I found out I was pregnant! Anyway, I never did stop exercising, but I sure did change my routine.

      I started using machines because the gym at the property has them. I’m liking it. It feels safe. I can lift heavy and not have to worry about dropping anything or my alignment.

  2. Fatigue has slowed down how much intense interval training I do but I am still able to walk consistently and lift weights 3x’s a week. I really am enjoying weight training. I lift heavy and then sit down and rest between sets. It’s perfect. I cannot imagine just stopping all my exercise. It’s helping me so much to deal with (ironically) the fatigue and the nausea. It just feels good to move and be active. I have backed up a little on weights for things like back squats and I always use the squat rack as a safety, lunging using dumbbells instead of a bar. So there are modifications I have to make as I feel my center of gravity shift but nothing too big. I intend to keep training all throughout and as I feel my energy come back, add back in interval training and running.

    • Lifting weights seems to be the ideal pregnant workout for me. Well, that and yoga. I do the same. I do a heavy set and sit down often.

  3. I’m 13 weeks pregnant with my second child. I work out 5 days a week and swear it’s what has kept the fatigue away. I kickbox on Mondays, 1.5 hr tota body weight training class followed by yoga on Tuesday, semi-private martial arts class on Wednesday, spin on Friday and swim Sunday. I kickboxed up to 8 months pregnant with my first and plan on going until my body tells me to stop. I just need that time for myself. And I think the general recommendations for exercising that you covered are totally misleading and love that you called out the facts and fiction.

    • Ali,

      I wish I had that much time for exercise! Of course the business of my schedule goes up and down but lately it’s just been crazy. This week I’ve managed to make it to three yoga classes. I’d be really happy if I could do 1 or 2 hours a day. That’s probably not going to happen until the book is finished though…

      Anyway, hats off to you! I’m sure all that exercise is helping you to feel great and give you energy even though it might be a little hard to get moving at times.

  4. I am so passionate about exercising while pregnant!!! I had lost about 20lbs prior to getting pregnant with my DD so putting on weight was very hard emotionally for me. Being proud of what my body could still accomplish helped a lot with that. I ran 3-4 miles a few times a week up to 36w with my DD and to delivery with my son. I also did aerobics (body pump), weight lifting and pilates. I remember jumping rope the day before my daughter was born – the people in the gym were dying! My trainer says she uses that story to goad clients on all the time.

    I choose to have c-sections (long story, but right choice for me) – and still I was backing working out and running at less than 3w pp. I recovered faster than most of my friends who had natural deliveries. I gained 31lbs with each pregnancy and lost it within a few weeks (Breastfeeding helps a lot with that too!).

    My kids are both super healthy and active as well. I really want them to have a legacy of good health (so NOT the norm in my family!) and it begins in the womb!

    • That’s awesome Sarah! I had a c-section too and recovered so fast it was shocking. I’m sure that has everything to do with being fit (and eating well of course). I couldn’t imagine not exercising while pregnant.

  5. Hi Peggy,

    Sorry this is not very relevant to this topic, but I couldn’t find where to post it. I started eating a primal type diet just before I found out I was pregnant. I’m only 7 weeks, but am experiencing difficult & sometimes painful bowel movements since eliminating grains (despite trying to stay hydrated, eat veggies & fats). Jack Kruse suggested magnesium supplements, but I’m not sure if they are safe during pregnancy. My OB doesn’t know. What do you suggest to counter this? I’m afraid it will only get worse as the baby grows.

    Thank you so much for all your great info!

    • Magnesium supplements are probably fine. I take one actually. I take magnesium glyncinate or chelated magnesium. This is easier on the digestion. If you are constipated, magnesium can help – it can help with a lot of things, however, there may be a cause beyond magnesium deficiency. Bowel problems of all kinds can cause constipation. Look into your diet and see if you can pinpoint intollerances. If you’re haven’t already, eliminate packaged foods and try to eat mostly fresh foods and lightly cooked meats. Fermented foods also often help with this as well.

  6. At my studio I’ve seen pregnant women with big bellies doing intermediate/advanced Vinyasa yoga with just a few modifications. I remember seeing one of those women in my class, and just a couple weeks later she came to the studio with her newborn!

    I know a lot of health bloggers have written about doing yoga while pregnant – healthereatsalmondbutter is one.

  7. I had a very fit (lifting heavy 3x week all the way to 42 weeks!) pregnancy with my first and am a big advocate of pregnancy fitness, but I will say that in my anecdotal research, labor is actually much harder when you are fit than when you aren’t! With my second, all of the demands in life were too much and fitness fell of the plate, and my labor was so much easier! This has been true for almost all of my friends, too, regardless of whether they’d had a previous baby or not. None of my friends are generally unhealthy, but not all are actively fit.

    My midwife said to give up squats in the last month to let that area loosen up a bit…so I’ll pass that rec on.

    • All that lifting right up until delivery may have made you overly fatigued. As you get closer to delivery it’s a good idea to start conserving energy. You’re not going to lose any of your fitness by taking it easy for a couple of weeks. Also, second labors usually are easier in general! Once the body has opened up, it will open up again much easier.

  8. I worked retail throughout my entire pregnancy, so five days a week I did brisk non-stop walking for 8-9 hours a day (ok, not totally non-stop, but pretty dang close), and up and down stairs (our store was on 3 levels). I felt great and didn’t have any problems at all until about 35 weeks when I had to slow down. At that point , even though I didn’t gain much weight, it got really hard to lug around all that belly. Never had a touch of swelling at any point. I also did prenatal yoga, although somewhere around 25 weeks I started being unable to lie on my back. I’d get dizzy and nauseated after 30 seconds or so. No bueno!

  9. I had another thought for women who want to run or do high intensity workouts later in pregnancy. At about 26w with my 1st pregnancy I started to have discomfort when I ran. I purchased a post-partum support band (nice and wide, probably 8in wide – the pregnancy ones I found were only 2-3in wide) and wore it when I ran. It gave me just enough stability during my runs to help everything feel secure. I think I started wearing it a bit earlier the 2nd time around maybe 20-22w – whenever I felt my stomach changing my center of gravity. I didn’t really need it when I was weight lifting or doing short intervals, but on long runs and walks it was great.

  10. I’m 25 weeks pregnant and still keeping up a pretty decent exercise routine, combining endurance sports and lifting/strength training. The strength training feels best. Baby is sitting really low so running has been uncomfortable (need to pee every 10 minutes!) However, last week I cross-country skied the 50k American Birkebeiner race in Wisconsin. I wasn’t 100% prepared for it, but I took it slow, ate and drank plenty on the course, and recovered just fine! It’s nice to know I can still keep my athletic identity while pregnant :).

    • That sounds like so much fun! Slow or not. This weekend I think I’m going to go snowshoeing. I’m not too thrilled about the scarcity of bathrooms out in the woods though. I’ve had to pee a lot too during this pregnancy too. It’s crazy. My midwife suggested buying one of those gadgets that allows girls to pee standing up. :D

    • Steph – in hopes that you receive this, I’d like to chat with you about skiing the Birkie while pregnant. Like you last year, this is something I don’t want to give up this year during my own pregnancy and would like to hear your thoughts/experience. Thank you so much for your time!

  11. I worked out throughout my first, second and third pregnancy, alternating between bodyweight HIIT routines and kettlebell workout.The first 3 months were a bit hard in motivating myself but otherwise i felt great all the way. I gained the minimum required weight, my babies were small but fit and very healthy, and my labors were fast and easy (even though that may sound weird). It took me with all 3 under 4 hours, i didn’t tear or anything, didn’t use any medications and recovered really fast after. Babies all slept through the night at 5 weeks pp and I started exercising again about 3 weeks after (modified) Baby nr 3 is 9 months now and i feel, and look as if i’ve never been pregnant, lol.. I would recommend every woman to continue if able, it is so worth it!!!! Good luck on your journey :o)

  12. First and foremost, congratulations on your new baby girl, Peggy! I found your website right around the time my husband and I were TTC our first child. We had spent the last 5 years modifying our lifestyle to be more healthy, fit and organic and after finding your site a Primal way of life seemed like the next logical step. It has been such an incredible source for me throughout my pregnancy, I’m totally looking forward to your book release!! We got pregnant right away and I’m now 24 weeks along with a healthy baby boy! My pregnancy has been uneventful and completely enjoyable so far. I haven’t experienced a single “traditional” pregnancy symptom -no nausea, no fatigue, no mood swings, no aches or pains, no heartburn, no headaches, no cravings, no aversions, no sleeplessness, no swelling, no rapid weight gain, no loss of muscle, etc. I attribute this to my *mostly* primal diet (still working out a few kinks) and having continued the same levels of exercise throughout. My pregnancy workouts have not changed since pre-pregnancy and I always look forward to them. To answer your question about exercise, a typical week for me looks like this: Monday – Full body weight routine (squats, bicep curls, pushups -standard and triceps-, shoulder press, calf raises, dead lifts), Tuesday – 45 minute hike at a local trail near my home (about 3-4 miles with at least half being uphill), Wednesday – Rest, Thursday – same full body weight routine as Monday, Friday – 1.5 Hours of hiking at a local mountain (1250 ft) and trail (same as Tuesday) by my house. About 6-7 miles total, Saturday – 30 minutes of yoga at home and Sunday – Same 1.5 hour hike & trail walk as Friday. If weather does not permit me to be outside, which is always my preference, I will usually substitute a 30 minute aerobics DVD at home. I plan to keep up my current schedule until my body lets me know it’s too much and then I will modify. I have full intentions of staying active throughout my entire pregnancy, even if it just ends up being a daily walk near the end. Thank you again for your “against the grain” approach that makes so much more sense to me than the conventional advice I’ve read and been given from my doctor. It’s refreshing!
    Be well and all the best to you and yours!

    • Thank you Bethany. Congratulations on your pregnancy and keep up the good work!

  13. I only went snowboarding up until I was 3 months pregnant and I didn’t go super fast and I didn’t do any tight trees and I didn’t jump. So actually it was kind of boring but it was nice to be up in the mountains and to breath the air and all that. But mainly I think I was keeping my boyfriend company. :)

    I wasn’t looking for an ok from a doctor or midwife. There is so much prevailing nonsense out there. So I tend to do my own research on things like that and make informed decisions, rather than believe what someone else heard and decided to believe.

    After 3 months there is a chance of injury to the abdomen which could affect the child so that’s when I, and other authors, thought it would be smart to quit. Plus my snowboarding pants weren’t fitting as well anymore. ;)

    • Thanks! I am not pregnant yet but trying and it can sometimes be difficult to separate fact from fiction. IT’S SOO FRUSTRATING!!!! I can spend hours researching a question I have and find nothing but conventional wisdom. I really appreciate your blog!! Having done my undergrad work in Anthropology I know that pregnant women living in traditional societies would have had a MUCH more physical lifestyle than any of us do today and yet the earth is populated to near capacity so something must have gone alright;) Are there particular sources concerning pregnancy myths that you might recommend I further my reading with? Oh, and I am so excited about your book! Can’t wait to get a copy!

  14. Wow, you went snowboarding while pregnant!?!?! That’s AWESOME! I’ve been lead to believe its not ok AT ALL. But when you live in the great state of CO;) where there is so much awesome riding to be had its so hard to think about giving up especially now that winter is approaching! Did you just decide to do it or was it ok’ed at any point in time? I guess what I mean is…how did you know it would be safe?

  15. You said one myth is: “Abdominal exercises of any kind should be avoided after the first trimester.” There is not a lot of information online as to which abdominal exercises are okay. I’m doing a boot camp 3x a week and while everyone else does crunches I’ve been doing side crunches. I’m 18 weeks and I’ve been comfortable so far with that. What else can I do? Can I do side crunches in my 3rd trimester. Any advice on abs would be appreciated!!!

  16. Hi, I have just found out I’m pregnant again after a miscarriage two months ago. I have been practising ashtanga yoga for years but have been told to stop by my teacher, and even the pilates instructor at my gym turned me away until I’m 12 weeks. Now I am feeling a mixture of worry for the things I’ve already done in the last month (jump backs and twists in yoga) and frustration that I am supposed to sit it out for so long! I’m keen to carry on doing something as I don’t think it’s good to just stop and then take it all up again if 2 months… any advice anyone has I’d be very happy to hear! thanks

    • Honestly, it sounds more like they’re trying to protect themselves from any perhaps undue blame for allowing you to continue to practice there if you do miscarry early on in this pregnancy. I really don’t think it has anything to do with yoga being dangerous for pregnancy at any time.

      • Good call! I really can’t imagine why anyone would tell you not to do yoga or any other reasonable exercise early in your pregnancy, unless you were ill to begin with, but even then, yoga can be very gentle.

        I did yoga while I was pregnant and it was great. When you get tired, rest. Drink lots of water and avoid most twisting poses. Your body will usually tell you when you should quit inversions.

        • Thanks Michelle and Peggy, I have done some research and designed myself a yoga practice to do at home for now. I’m keeping crucifix twist in as it feels open at this early stage. I do think the response of my gym is down to the teachers protecting themselves which I have to respect, but I will look forward to getting back to classes after 12 weeks!

Leave a Reply

Required fields are marked *.