Got Milk? Running and Breastfeeding

Breastfeeding symbol
Boobs: not just for being smushed by sports bras. (Photo credit: Wikipedia)


Boobs. It’s one of our favorite topics around here and, surprisingly, one of the top Google searches that leads readers to our site. Well, not readers like you; rather, dudes looking for women runners with bouncing boobs (true story!). Here’s the post they get. Anyway, this isn’t that kind of boob post. Today we’re talking about boobs doing their job. You know, breastfeeding.

Most research on breastfeeding and exercise focuses on the effect of exercise on the quality and quantity of milk. It’s really nice to know that moms who exercise generally produce the same quantity and quality of milk than our non-exercising counterparts – Hooray! However, little research has been done on breastfeeding’s effect on athletic performance and a woman’s ability to train at a high-level while nursing. As a result there are not a whole lot of useful running and breastfeeding resources for serious runners.

That is, until now!

First, let me tell you I am not a doctor, lactation consultant, healthcare professional of any kind or any kind of expert. This post is a combination of my personal experiences and information from my health care providers as interpreted by me. If you have any doubts about the impact of running on your own health or that of your child consult your doctor or lactation consultant! Also, if you think I’ve made a mistake, missed something or just want to share your own experience, the comment section is for you!

Anyway, as of this writing I have been pregnant and/or nursing continuously since March of 2008. Yes. That’s 5.5 years of nourishing the sweetest little parasites on earth. I love my kids and breastfeeding them is important to me. Even though in my experience it has impacted my ability to train and race, and even though my running is way important to me, running will never dictate how I feed my children. I breastfed my kids for two years to the extent I could and so far I have been able to continue even while pregnant with the subsequent kid, so I expect I’ll be able to do it this third time (because I am not ever going to be pregnant again! WOO!) Even so, this doesn’t make me an expert (see previous paragraph) but I do have quite a bit of experience training or attempting to train while being a nursing mom.

At first, nursing boobs are big and ouchy, but this gets better. Trust me!

A mother breast feeding—a process that facilit...
This post is about breastfeeding and running, which is not to be done at the same time. (Photo credit: Wikipedia)

First let’s discuss the stages of breastfeeding. Things are way different during month 1 than month 6, 7, 8 or 18. During that first month of breastfeeding, your boobs will be at their hugest, but luckily this corresponds with the weeks you’ll be recovering from birth anyway. Your milk will come in sometime between 24 and 72 hours after delivery and this is the absolute worst you will feel. Your boobs will be gigantic, full of milk and probably painful. I am not a big fan of this moment! But it doesn’t last long and your boobs will adjust to the demands of your baby quickly. Even so, they will still likely be a lot bigger than usual for a while and when you start back running you might consider “double-bagging,” or wearing 2 sports bras at the same time, for extra support.

Most breastfeeding moms these days feed their babies only breast milk for the first 6 months. Over this time, breastfeeding takes a lot out of you. As the baby gets bigger she eats more, which means your body needs to make more milk. The more milk you make, the more energy your body diverts from other things (like running) to making milk. After you start incorporating solid foods into baby’s diet, her demand for milk will slowly decrease as will milk production’s demands on your body. Your boobs will start shrinking back to normal size and still do a mighty good job of feeding her. It often shocks me what my little boobs can do!

Once my kids got to 12 months they started on cow’s milk and over this next year, I slowly cut back on nursing to where I only nursed before naps and bedtime by the last few months. I’ve never nursed the last few months without also being pregnant though, so I’m not sure how only nursing a couple of times a day impacts training. If anyone has that experience, please share!

You can train for a marathon while breastfeeding, but have reasonable expectations. 

Especially when exclusively nursing for those first 6 months, your body knows its first job is to sustain your baby and second job is to sustain you. Running is extra. This is not the time to expect to train for and race big PRs. That’s not to say it’s not possible, because it certainly is! Several of my PRs were run while nursing my second child, but it’s not something any breastfeeding mom should expect to do. Be open-minded about breastfeeding’s demand on your body. You might feel ok, but hard training may impact your milk supply if you’re losing weight too quickly or become too lean. More often than not, if you are training too hard for your breastfeeding body, you will break down before your milk supply is affected as your body has a system to deal with your shenanigans to protect your milk supply.

Just in case though, there are red flag warning signs that hard training may be affecting your milk supply.  If baby doesn’t seem like he’s satisfied after nursing or his wet diapers become less frequent it’s time consult your doctor, lactation consultant or pediatrician, and you may need to take the training down a notch.  It’s important to keep an eye out for those warnings.

Personally, I found running about 80% of my normal training volume and no really hard workouts for the first few months worked fine and helped get me back into shape fairly quickly. By 6-9 months, after the introduction of solid foods, I have usually been good to go with training. However, this last time has not been so easy, which is likely more a cumulative effect from three pregnancies and nursing babies in a relatively short period of time. I’m almost 11 months postpartum, still nursing 6-7 times a day and still not ready to hit it hard yet. Soon though, we’ll be starting whole cow’s milk, so I suspect as I cut back on nursing sessions I’ll start feeling stronger.

A 1872 nursing chemise shows a movable flap th...
I find sports bras and t-shirts offer adequate easy access to the goods. (Photo credit: Wikipedia)

Hydration: you don’t need to go nuts, but be sure to drink to thirst.

Breastmilk is made up mostly of water, so you need enough water in your body to make enough for baby. When we run, we sweat and lose water, so it’s extra important that we runners hydrate. But you don’t have to go crazy. Drink to thirst. This might mean you have to drink a little more than normal (on average nursing moms drink about a liter more than non-nursing women per day), but your body will give you cues for what you need. If you experience constipation or have dark urine, you’re definitely not drinking enough, whether nursing or not. I know I need to drink more when the tips of my fingers and palms feel dry. I try to drink a glass of water after nursing and two after running. This works well for me.

Even after super hard runs, that milk is delicious!

Not that I know. After all this breastfeeding, I’ve never actually tasted it. Actually, never in my life since I was born in the formula-heavy mid-70’s. However, my kids slurp that stuff right up no matter what. I’ve jumped off the treadmill drenched in sweat to the point that I’ve soaked them and they haven’t blinked. I have one friend who said one of her kids refused to nurse unless she wiped the sweat of her boobs with a wash cloth after running, but even the scientific studies show there is no effect on the taste of your milk caused by exercise.

Recovery takes a back seat to churning out the milk.

Remember, when you’re nursing your body’s number one priority is not to turn itself into a world-class athlete, but to maintain its milk supply. This might mean that you do not recover from hard workouts and high mileage as fast as you would if you aren’t nursing. As for you, the demands of breastfeeding may mean it takes longer for your body to recover from hard workouts. With energy diverted to churning out the liquid gold, there’s less to go around for “extras” like fixing that tweaked hammie posthaste. I’ve definitely noticed a diminished capacity to recover this time around.

Relaxin turns you into injury-prone Elastigirl.

When you were pregnant, a hormone called relaxin loosened your ligaments so that the baby could pass through your pelvis. If you nurse, this hormone remains in your body after birth until you stop nursing, which means you might be more susceptible to injury.  This might also impede your body’s ability to heal those little niggles we all get from hard training. Grrrreat.

You will never ever sleep again. (At least it will seem that way for a while.)

Breastfed babies tend to wake-up more during the night in their infancy, than non-breastfed babies. (The dark circles under my eyes can attest to that!) That means as a breastfeeding mom you are going to be tired from both lack of sleep and from the energy your body uses to keep up the milk supply. It’s definitely not an insurmountable problem and you will adjust to the broken sleep and the shorter spans of REM, but you still need to factor in the lower quality Zs when determining how hard to push your training. Not getting adequate sleep further inhibits recovery, so be sure to factor that in when determining how many hard workouts you want to squeeze in your training weeks.

The Booby Bonk.

Their insatiable appetite for breastmilk might put a damper on your training, but it’s temporary and they’re pretty darn cute. (Photo credit: Wikipedia)

I admittedly don’t have a ton of marathoning experience. I ran three before having babies and two since. I never ever had problems with bonking (running out of glycogen to burn) either in training or racing before I became a nursing mom, but I have many times since. I couldn’t find a study on this, but I can’t help but wonder if a nursing mom’s body is not real keen on burning fat for fuel to the extent necessary to train for and especially to race a marathon. This is pure speculation, but something to consider if you plan to race marathons while nursing.

Once again, I’m not a doctor, not a midwife, and not an expert on lactation, just a woman who’s breastfed three kids and kept running nearly the whole time.  All this is my conjectures based on my experiences.  But as someone who’s often wished there was more information out there, I’m excited to share my experiences with you and I’d love to hear about yours!

Got questions? Got advice for other breastfeeding running moms? Please share! 

Salty Running boss and mother of 3 little ones with PRs of 3:10:15 (26.2), 1:25:59 (13.1) and 18:15 (5k). I love to write about running culture, mental training, and fitting in a serious running habit with the rest of a busy life.

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  1. Dang, I can’t imagine breastfeeding while marathon training. It’s hard enough without the extra energy required to make milk! Huge props to you for doing both!

  2. Thank you for this post! Even though I’m still ~14 weeks from birth day, I’m already considering post-baby goals and have even had a few friends inquire. I am definitely planning to breastfeed but had no idea how that will affect me. Definitely bookmarking this post!

    1. Definitely let me know how it affects your training! As I recall, I got back to “normal” pretty quick after my first. Now I wouldn’t know what normal felt like 🙂

  3. Yay! Perfectly timed post for me! I’m at 30 weeks prego (and still running 25-30 miles per week!! Yay!!) and I hadn’t even considered that breastfeeding would hinder my running… Duh! This is a great reality check for me and my marathon PR at 4 months postpartum dreams 🙂 I’m a little anxious to get back to the fast miles without 25 lbs of boobs and belly… But I guess I need to remember it’s not going to happen overnight -especially with a newborn breastfeeding all the time. Thanks for sharing your experiences here – very helpful!! I think I might push my PR dreams back a bit now. My future bonking self thanks you!!

    1. Congrats! First, i definitely don’t mean to discourage you! If that’s your dream, go for it just be open minded about it – your body might not go along with the program and you might need to adjust the goal is all. As i said, I know some people who trained hard and ran great while nursing even within the first few months. Don’t expect to be one of them, but be open to the possibility that you could be. Postpartum time is a time to balance your goals and type-a-ness with cutting yourself some slack and really listening extra close to your body. I hope that makes senses good luck with everything!

  4. My girls are retired, but I’m still glad to see this. I was able to start running at 2 weeks postpartum with my first, and it didn’t interfere with breastfeeding. Neither of my girls ever seemed bothered by post-run milk – or sweat, for that matter. I don’t think I ever got up over 30 mpw or 10 miles while breastfeeding, though. But running definitely didn’t interfere with milk production, I had plenty of that to go around.

  5. Thanks for such a great post! I have a 7 1/2 month old (my first) and have been training for the Richmond Marathon on 11/16. It’s my third marathon. I definitely noticed that training took more out of me while exclusively breastfeeding, especially over the summer in the heat and humidity. I took it pretty easy the first couple of months, and increased my mileage more gradually than I normally would have. I’m still hoping for a PR, but no matter what my time ends up being, I’m definitely just happy to have gotten through training for a marathon with a baby so young. I’d say the things that have helped me the most have been a supportive husband, staying well hydrated, and eating a lot!

    1. Hi Kim, so you ran a marathon while breastfeeding an 8 month old? I’m currently training for the NY Marathon in November and my little boy will be 6.5 months old then. Were you exclusively breastfeeding up until the race? I guess I’m just wondering how you managed the day of the race – being away from your little one for so long and not being able to give your breasts some relief… Any advice would be appreciated! J

  6. Awesome post!! I can definitely relate – I nursed my now almost 26 month old until he was 20 1/2 months! I ran several half marathons during that time and one marathon! I *almost* nursed him while running – about as close as you can get. I ran a 10K with him in the jogging stroller when he was 4 1/2 months old and wouldn’t you know, a mile and a half in he decided he was hungry. So I parked the stroller on the side of the road, took him out and sat down on the curb and nursed him!! Got compliments from an older woman who ran by while I was nursing him, too!

  7. Great post! I’m 8 1/2 months into nursing baby number 2. This was really a good reminder about how draining training while nursing can be. I have completed 2 marathons and 2 half marathons since she was born in August and have noticed the drain on my body and slow recoveries. However still feeding baby girl- my number one goal- and she’s thriving. I do have to pay attention to hydrating and eating enough as some runs I’ve noticed my supply taking a hit. I do want to second that it’s important to have realistic expectations whole also dreaming big if you can. I PRed in the marathon last month after 20 of them –
    and had in the half last weekend. So it’s possible. I find that with two little kids I don’t have have much time and try to make my workouts count without a lot of miles in the bank.
    Recovery takes longer and it’s important to be kind to yourself! I do eat a lot and find it’s almost too easy to lose weight nursing and running long distance.
    So all you running mamas- it’s possible- just respect the body and it’s limits and snuggle those babes all sweaty after a run!!

  8. Wonderful post, I’m just trying to get back into running post baby and will be training for a half. No time goals, just completion! Need to remember to be kind to myself while training, stay nourished for both performance and recovery… All of which will allow me to provide for my little ones, milk and otherwise!

  9. I started running for the first time in my life at age 26, while I was breastfeeding my now-3 year old son. I completed two marathons and two ultra marathons between October 2012 – December 2013, all while still breastfeeding.

    I’m now 5 months pregnant with my second son, and continued to breastfeed and run into month 3. I run once a week now, but no races as I’m recovering from a foot injury and needing to heal and focus on pregnancy.

    Because I’ve never run when I WASN’T breastfeeding or pregnant, I simply have no comparison!? I felt pretty invincible out there, though. My milk supply never slacked or suffered, not even when I was training intensely and doing track workouts, racing monthly, and still managing to put in 50-hour work weeks as an agency manager.

    I breastfed my first son to age 3 years 1 month (just weaned him 2 months ago and I miss it!!! It was our bonding time.). I dearly want to do the same for our second boy, too!

    And I also want to run a 100-miler.

    Ask me in a year or two how it goes! 😀

    1. I hear you! I’m on year 7 of being pregnant and/nursing and at this point I wouldn’t know what it feels like to train win my body all to myself 🙂 I’m kinda hoping for a nice little fitness bump when I wean in a few months, but even if not it was well worth it. I cherish this time with my kiddos! Congrats on all your accomplishments!

  10. I am an ultrarunner and have run ultramarathons for 3+ years (50K-100 milers). I have asthma and when I’m pregnant (currently babe #5) asthma is not well controlled due to the medications risks (so I use less effective “safe” meds), which means I can’t run without major wheezing. Hence walking which does not feed my soul like those longy long runs do. Nonetheless, with babe #4 I started running at 2 months post partum but not more than 1/2 mary distance as my milk kept taking a hit. Now as an entire year has gone by without me running a 100 mi(my LOVE), as I think about the toll nursing has taken on me in the past with my four prior kids, I’m not so sure a 100 can be in the books for me in 2015. I realize it’s a small price to pay in the grand scheme of things… I’m due 10/2014. I’ve struggled a lot with body image this time because I haven’t been able to run and I think it’s affecting my self esteem. I know that having a body that “knows” what to do and can nurse a babe for a year plus is a big gift and I’m trying to stay focused on that. This was an unexpected baby (I’m almost 39 yrs old) and so I’m grappling at all info about nursing and training that I can. Thanks for this post!!!

  11. I am about to start taining for my first half marathon and I am a mother of 2 (2.5 y/o and 8month old) I am still nursing the 8 month old. I have been running about 15-20 miles/week since he was 3 months old and just wondering how many calories a day you ladies are eating to nurse and train successfully?

    1. I never really tracked my calories. I never seemed to have a supply issue, so I was never worried about that. As for performance, I’ve found that I need to time eating so I don’t become hypoglycemic/bonk and I bring gels with me when I never would before just in case. For some runs, I need them (or an alternative) or I can’t perform – e.g. evening track workouts, morning long runs, etc (take one with about 6-7 miles to go). I was never a big gel fan, but they’ve saved many a workout for me lately and I’m not currently training for a full marathon so training my fat burning system is not a top priority. As for timing of eating, I need to make sure I eat within 2 hours of a run. If I run early in the morning without something I can expect to be slow slow slow and struggle after 50 minutes or so! I’ve only noticed this being a “thing” for me since my 3rd, although I had a couple of bonking incidents after my first and second too. Anyway, I think this is something pretty unique to each woman. If anyone has a better answer feel free to chime in 🙂

  12. I’m so glad I found this post! I’m training for my first half, and am nursing my 15 month old. I think I experienced my first “bonk” on a recent run. Only thing is that it was not a long run, but I pushed my girls in the double stroller so it was a hard run. And I felt fine until about an hour post run. I ended up with a major headache, felt generally awful and even had some blurred vision in one eye for a few minutes. I’m pretty sure it was due to inadequate post run fueling, although I did eat some after the run. In your experience, can bonking happen an hour or more after a run? Do you have any tips on how to prevent that from happening?

    1. THat sounds like a migraine. Was it hot/humid? In my experience bonking happens during the run – you feel hungry and then … WHAM! You feel dizzy, heavy and can’t go. I have felt hypoglycemic as a nursing mom when not running. It’s similar to the bonk, except I get really cranky or emotional along with the hunger and light-headedness. I would consider talking to your doctor about what you described above just in case. Good luck with the half! Keep us posted on everything!!!

  13. Thxs for this post! Its crazy that there isn’t more out there on this. My daughter is 9 months and I am 2 months out from the Chicago Marathon. Its my 6th marathon…and I’m an older 1st time mom…43…so I cant tell if my slow recovery is from post pregnancy stuff, age, and or nursing. Its probably all three, but glad to know I am not alone!

  14. This was great, thank you! I have been feeling the same, like I just don’t have that oomph to kick it up when I want to. I had 2 in two years and am still nursing and no amount of determination seems to overcome the sluggish swagger to my run which I wholeheartedly attribute to breastfeeding. It’s so frustrating watching my non-mummy friends improving while I stay stuck, and there’s probably going to be a #3. I’ll be watching your blog for your take on weening and whether you feel you fully bounce back!

  15. Great post, I wish I had read this before I started training. I’m running the NYC marathon and have been nursing my 10 month old while training. It’s my first marathon & I’m wondering how you managed to relieve engorgement while running? We have to leave 5 hrs before the race actually begins so I’m imaging I will be away from my son for at least 10hrs!! Any advice would be appreciated!!!! Thank you!

    1. A friend of mine told me that you can hand express milk. Check out or google hand expressing. Alternatively, maybe a small hand pump in your gear check bag?

      1. Danielle, I think I read somewhere that the NYC marathon is putting together a pumping station at the start line. Check the website or email them.
        Otherwise, like Salty said, hand expressing is a good option. I’m a big fan of my medela manual pump as well.

  16. my third baby is 4 months old, i didn’t start running till my second was 9 months old. I “ran” right up to the end of this third pregnancy and managed to get back into it, casually, 4 weeks post emergency c-section. I have found that running leaves me soooo hungry and thirsty. And tired. Agree with everything in the original post, slower recovery etc. Looking forward to starting training for my first marathon. And I’ll hopefully still be nursing 🙂

  17. I’m on my third child since 2010. I’ve been pregnant in every year since 2009 and breastfeeding for over 4 years straight with the exception of a 2-3 month break when my oldest weaned himself before my second was born. I even nursed the second and third together for about 5 months. I recently told a friend I would help him train for a marathon. I’ve done three pre-baby and I’m an average to decent runner. I’ve religiously run and weight trained through my pregnancies and subsequent recovery periods. We really started upping the milage about a month ago though (my son is 8 months) and my supply has TANKED. The baby is never satisfied, I’m getting less and less when I pump, he wakes up at night desperate when he used to be satisfied. I just called into the Dr for a Rx after trying everything that I could think of; tea, oatmeal, fenugreek, water, water and more water. I’m very frustrated but after my 8 on Friday and 17 on Sat I had a REALLY hard time with milk production. Everything you read says that’s not the issue, but I can’t help but think the studies aren’t targeting high milage runners. I was glad to read your post. It kills me to cut back milage, but after reading your post it makes me think I’m not completely crazy and maybe backing off (keeping it under 10) will help. I guess we’ll see. I think a combo of ramping milage up too fast and loosing body fat too quickly because of the running has done me in. Just hoping the Rx can bump it back to normal before we have to try the formula route. Thanks!

    1. We have very similar pregnancy/nursing stories! It’s probably just a rough patch. You’re so close to the year mark! Do you read I always found super helpful bf’ing info there. I hope you figure everything out. Keep us posted!

  18. Thanks! I’ve started reading around. I’ve always been so lucky to not have issues until now and I have a large group of family and friends who nurse so I’ve never had to research it on the internet much. I’m getting a crash course these days. It’s funny how the baby’s frustration at the lack of milk causes an immediate physical (heart rate spike) and emotional (anxiety) response. Ironically enough my outlet for anxiety is usually running…talk about a catch 22. ;p

  19. Thanks for the post! I am just 4 weeks post partum, so I am still waiting for the thumbs up from my Dr. to start working out. I signed up to run my first half marathon in May 2015. I am so excited! This post answered so many questions that I have or have had.

  20. I just gave birth to my 3rd child in April and was curious if running will ever effect my breast milk. I plan on breastfeeding my child hopefully for a year. But I do want to get back in shape again to train for a half marathon in October that I usually do once a year. reading your article gives me great insight and hope that it is somewhat possible to still have enough breastmilk and have healthy children. Thank you!

    1. I personally had no problem but I was home with my last baby not working and pumping. I started up running again as soon as I could (within a week so it was more like glorified shuffle walking for less than 2 miles). Until about 4 months I ran 5 miles at most. Baby didn’t notice any change in taste and I didn’t notice any change in supply unless I felt particularly dehydrated at which point I would drink a bunch and continue nursing and everything returned to normal within a few hours. That’s my only advice, hydrate well so you can both sweat and lactate. Best of luck!

  21. Thanks, this post is really useful. I have a 10 week old son who I am exclusively breast feeding. I’m also training for the NY Marathon this coming November. My son will be 6.5 months by then. I’m really nervous that my supply is going to dry up, and I love breast feeding my son (way more than I thought I would!), and want to continue to do it for as long as I can. I am going to see a lactation consultant and get some advice… but would you mind telling me how you cope on race-day when breastfeeding? What I mean is, It’s likely to be 8 hours or so that I’ll need to go without feeding my son. He will be fine as he can have pumped milk, but what about me? Running with engorged breasts will be horrible! I’ve just finished weaning him off night time feeds and every morning my breasts are so engorged it’s just awful. There’s no way I could run a marathon in that condition…

  22. I have never run before in my life but I would like to start. Signed up for the Disney Half in Feb. I am currently nursing 2 10 month olds. (My boobs are massive) Any advice for starting to run? How many calories to add? How much more water to drink? I already have to eat about 3000 cals a day and 120oz of water to feed these little ones. Anything less then that I notice a drop. Thank you for your help and the article was wonderful!

  23. Love this post!! I’m finding that I really bonk on any run longer than 8 miles. I don’t know if it’s because I’m out of shape from pregnancy (haven’t run over 8 miles since 32ish weeks pregnant), or from breast feeding, or both. I’ve found that I need to eat after about 6 miles, then I can tolerate a longer run. But usually I can run an entire marathon on just a few sports beans, so this is a real change for me!! Does this get better? (My baby is 9 weeks old now), or does it persist the whole time while breastfeeding?

  24. This was super helpful! I have totally noticed a slow down in recovery while nursing. I haven’t noticed the bonking problem yet, but my longest run has been 12 miles so it may still happen 🙂

  25. I’m 22 weeks pregnant now and am already thinking about post partum goals now. This is my first baby so I don’t really know what to expect of my body! Do your boobs hurt while you run of you’re breast feeding? Do they leak a lot? Things to look forward to haha. I usually train for 12k to half marathon distance and before I was pregnant I could hold a 6:45 pace. Can’t wait to run fast again.

  26. Thanks for posting this. I am curious about the part where you said relaxin stays in our bodies until we wean. I started running when my baby was 3 months old, and that was in January. I am training for my first marathon but I have had FOUR injuries this year! Two ankle sprains, and then a stress fracture in my left hip, and now my right hip feels just like the other did when it had a stress fracture. I’m so frustrated but I am wondering if breastfeeding has caused my body to be more injury prone. My baby just turned one and we are still nursing. Any feedback would be appreciated!

    1. Hi Kim, I think this is one of those things that is a bit different for everyone. I started running after my second baby had weaned. I finished my first marathon a few months ago and i was still nursing my 3rd baby fairly frequently. I didn’t suffer any injuries, just a couple of tension spots. From my understanding injuries tend to have a lot to do with genetics. Find a great physiotherapist. Take up pilates. Do strength work. These are my suggestions. Good luck 🙂

  27. I ran my third marathon when my second child was 7 MO old. Completing a marathon is an accomplishment to be proud of, but it was extremely difficult. All the things Salty listed happened, difficulty recovering between runs, difficulty performing with decreased sleep and one would think I’d be super fit, but I really wasn’t. In general, I would say marathon training and nursing are not compatible, particularly when the baby is mostly just nursing. I had some blood work done prior to the race, and my hemoglobin and hematocrit were very low. Since my body’s priority was to make milk, internally I was depleted, which dramatically affected my performance (in a negative way), despite the fact I trained just as hard. Which brings me to my question. Can I compete well in a race like Hood to Coast with an 11 MO old who is nursing (my fourth baby). Also, the relaxin hormone stays in your body for six months to a year even after your done nursing, which can negatively impact one’s exercise and athletic goals.

  28. Hi Salty,

    Very nice And well written post. Thanks for sharing this information.
    I am 5 months postpartum and starting to run. However, I can barely run probably due to lose ligaments (or increased weight).
    I wanted to know your strategy about starting running postpartum.

  29. Just wanted to add my experience for anyone who has had a rough time like me…

    I was running 25-30 miles/week pre-pregnancy. I would run 2-3 short runs & 1 “long” run per week.

    Unfortunately, I had a really bad tear and subsequently longer healing time. I got back at it approximately 12 weeks postpartum. I could never make it past 3 miles without pretty bad cramping & pressure. After visiting my OB, he mentioned the fact that some women don’t heal properly and are more prone to injury due to the relaxin you mentioned. He suggested that I put running on the back burner until I was done nursing. Sad day.

    I continued to run for a while, but the pain was too much. I had to decide what was more important to me. I decided to keep breastfeeding. My baby is now 13 months old and I almost have him weaned. I am nervous to get back out there but am hopeful that I can bounce back!!

    Thanks for the article!!

  30. Just came across this post, thanks for the share of it. I’m BF’ing my 9 month and training for a half. I completed a few halfs and a full prior to pregnancy and then a half 3 months post-partum. Your article hit the nail on the head. I couldn’t figure out why my body wasn’t reacting the same. This is great info and I appreciate that reminder that my body is FEEDING another human being and I have to be patient with myself and grateful I am able to produce milk.

  31. Thank you for this post. Very informative. My daughter is 17 months old now and I just got back into running. I’ve completed a handful of halfs and a full marathon prior to pregnancy. I want to start training this month for my first postpartum half marathon come june but I just cant leave my ebf daughter in the morning. She is still into night time feeding and I find it hard to train in the morning due to the demand. Any advice on how we could adjust and prepare her for my morning trainings? How did you handle yours?

    1. My daughter (now 3) ebf until she was 2 (she still night-nursed 2-5 times/night until the bitter end), I trained to race my first post-partum marathon when she was around 10 months, then trained/ran two more while nursing. I nursed her right before I left on my long run, left her with a sippy cup and snacks/food, and nursed as soon as I got back, I also drank mass quantities of water all the time, and carried/drank much more during my long runs. It was tough but doable. I got down to about 8 pounds under my normal weight from the demand so I was really good with eating a lot and continued to take my pre-natal vitamins and calcium, but when I stopped nursing my weight thankfully evened back out to normal. You can do it!!

  32. Well, this is what I typed into Google “pregnant nursing and training for a half marathon”. And your article came up! I am very newly pregnant, nursing my almost 12 month old, and plan to run the half I’ve been training for 4 months for (in about 5 weeks). Needless to say, I’ll probably throw my half PR out the window. If I can cross the finish line injury-free without puking, I’ll be a happy camper 🙂 After this half, I will have run three halfs while pregnant with each of my kiddos. I’m really thankful to be able to keep running.. But my body sure has changed over time. Thanks for the helpful info!

  33. Great article. Very happy I found this. My baby is now 16 weeks and I’ve been wondering why I am not recovering from my workouts. I am a very active person. Go to the gym on a daily basis and teach a cardio kickboxing class. Lately I’ve been waking up feeling terrible. Many of my questions were answered in this article. Thanks 🙂

  34. As others have stated, great article! My LO is 10 months old and I ran my first marathon PP this past weekend. I missed my goal by a whole 30 minutes and it really got me thinking about the effects of nursing on the body. Not to mention motherhood and how exhausting that can be! I also feel that my diet isn’t what I would like it to be right now because I just can’t find the time to eat like I would normally. Thank yo for sharing your experience!

  35. Thank you for the info! I’m almost at my 6 week post c section date and I can’t wait to get back into working out. I’m concerned though because my girls are so sensitive and the little bit of running I’ve done post partum has really hurt. The bouncing is so uncomfortable. I mentioned to my husband that maybe I need to wrap my chest in ace bandages.

  36. I don’t know why I didn’t come here first! This was my go-to site for all things running while I was pregnant, I totally spaced once I was nursing. great article, I am almost 6 mo PP and have noticed that after longer races (half marathon and up) my milk supply dips for about 2 days -I can tell because the volume I pump at work goes down a few oz, and my little man doesn’t seem to sleep as well and is always HUNGRY. Thanks for the information

  37. Thank you for the great article! I am 3 weeks pp with my first baby. I am exclusively breastfeeding and needed some info with training. I’m a 4 time boston marathoner (this will be the first year I haven’t ran boston since 2013). I am running a marathon in September and wanted to know what yo expect for training. Thank you!!!

  38. I just read our comment and have a question for you. I am one month post c-section, exclusively breast feeding and have signed up for a marathon overseas in October. I am currently producing a lot of milk so I’m able to freeze quit a bit. Looking back, if you I I I am 1 mo post cs and have a lot of milk reserve. In my situation, would you have considered ending breast feeding from the tap (as my husband puts it :)) prior to running your marathon? I am signed up for a marathon in October and wonder if I should just grow my supply so that I can quit nursing before race day. Thanks!

  39. I just used this article to help me understand and maintain my milk supply for my 1 year old as we are about to hike the Appalachian Trail together- hiking about 12 miles a day! Your post had some great info that will be really helpful while we are on the trail- thanks!

  40. Hi would just like to ask if you were affected by relaxin hormones as you ran while nursing?

    I am 9months PP and just returned to running marathons. Not sure if it’s the extra pounds that I am holding on to, or the hormones, but my knees and hips feel somewhat more wonky compared to before pregnancy.. is it true that while nursing, one still has a fair bit of pregnancy hormones?

  41. Great read! Have you noticed a difference in your heart rate while running? My heart rate seems much higher than normal and curious if I can chalk some of that up to nursing. This my third child and nurse each kid for 2 years.