Could Your Workouts Be Impacting Your Breast Milk?

Have you ever worried about postpartum workouts impacting your breast milk? Will it make your milk too sour? Reduce its nutritional value? Decrease your supply? We hear these worries all the time, and we want to dive into the science behind postpartum exercise and breastmilk production to get you the answers you need to exercise confidently after childbirth.

To clear things up, we busted four outdated myths on exercise and breast milk production (based on research), and then we have a few tips for any breastfeeding mamas who are currently working out or wanting to get started!

4 Reasons Why Exercise Will Not Negatively Impact Your Breast Milk

  1. Exercise will not affect the amount of milk you produce. Working out healthily and safely postpartum can help your body recover from childbirth, and the good news is, it will not affect your breast milk supply. Moderate exercise can help reduce stress levels, which may be elevated as you adjust to life as a new mom. Stress and very strenuous workouts can lower the amount of breast milk produced and potentially lead to issues such as mastitis, an infection in the breast tissue, so that’s why postpartum-specific workouts are so important. Gentle exercises that ease your body into activity and then steady, moderate routines will be your best friend!
  1. Your breast milk is still just as nutritious after a workout. Post-workout hormone changes naturally provide a mood boost and can leave us feeling strong and energized. And you can rest assured knowing that your breast milk has the same nutritional composition even if you workout regularly! Studies show babies grow the same whether fed with breast milk from mothers who exercise regularly or mothers who live a more sedentary lifestyle. Even more, studies like this one from researchers at the University of Leeds in London found regular exercise may encourage people to make healthier food choices, and the maternal diet plays a critical role in breast milk composition.
  1. Exercise while breastfeeding may pass lifelong health benefits along to baby. Although research shows babies develop the same whether or not their mothers stay active during the period they breastfeed, new research shows that maternal exercise might pass along other lifelong benefits through breast milk. A study published last year found that moderate exercise during pregnancy and postpartum increases something called oligosaccharide 3’Sialyllactose (3’SL) in breast milk. The presence of 3’SL can help babies develop immunological effects for fighting off infections. Researchers are looking into this further but currently believe that it may help reduce the risk of lifestyle conditions, such as obesity, type 2 diabetes, and heart disease later in life.
  1. You do not have to worry about the flavor of your milk changing. A common belief about postpartum exercise is that it can make your milk taste sour and cause baby to reject feeding. Previous studies have found the amount of lactic acid in breast milk does increase immediately after strenuous exercise. However, this only happens after strenuous exercise, and safely exercising in your postpartum period should be moderate-to-low intensity exercises that focus on helping the body recover. Low- and moderate-intensity workouts have not shown to increase lactic acid in breast milk. Keeping that in mind, if you want to eliminate any possible concerns, you can wait approximately 90 minutes after exercising to breastfeed. 

In sum, exercising as a new mother will not affect the nutritional composition, flavor, or amount of breast milk you produce (as long as you practice safe exercise habits), and may even pass on lifelong health benefits to baby. Are you convinced to get those postpartum workout routines going yet? Here are a few tips for safe exercise if you are breastfeeding:

5 Exercise Tips for Breastfeeding Women

  • Check with your doctor before starting any new exercise. Your doctor should give you full exercise clearance before you begin any new workouts during or after pregnancy. From there, we recommend starting slowly, introducing exercises gently, listening to how your body responds, and skipping anything that you are not comfortable with or that causes discomfort.  Remember: exercise should feel good. Staying active is part of a healthy lifestyle, but if it does not work at the moment, let your body heal from the incredible work it did and try again later — you are right where you need to be. 
  • Breastfeed or express milk before exercising, if possible. Exercising when breasts are full and tender can make moving around and bending painful, and breastfeeding or expressing before a workout can ease that discomfort. If you are still worried about your milk tasting sour post-workout, you can avoid that with a pre-exercise feeding or pumping session.
  • Keep healthy exercise habits. Proper hydration is a big part of healthy exercise and breast milk production. Try to have a glass of water at least every 20 minutes of active exercise, and continue to drink water throughout the day. Breast milk is about 90% water, and to stay hydrated, you should be drinking an average of 128 fl oz (or 3L) per day. The same rules apply for nutrition, and a healthy, balanced diet will give your body the fuel it needs to both workout and breastfeed (as you burn around 500 calories per day breastfeeding). Lastly, be sure to shower after exercising to clean off any sweat, dirt, or germs possibly on your skin that baby could ingest when you breastfeed later on. 
  • Try low-impact activities for a gentle, full-body workout. Exercise right now is all about helping your body recover, and you do not need to be overdoing it or trying to push the limits of your body. Very strenuous workouts at this time can do more harm than good so sticking with low-impact activities at a moderate-to-low intensity is the aim. Check out the Baby2Body app for workouts catered to your postpartum stage and focused on restoring lost muscle tone and building stamina back over time.
  • Choose the right sports bra for workouts. Finding the right sports bra is surprisingly important! Your breasts have grown more since having a baby, and choosing a bra that provides enough support and is not too restrictive can prevent things like mastitis from occurring. Bras with underwires tend to poke and prod in uncomfortable places, so we recommend trying a nursing bra with a soft cup that provides support with a reasonable amount of snugness. Unsure of what size bra to buy? Many department stores or lingerie shops do fittings for free and can help you understand your bra band and cup size! We also recommend going for cotton or other natural fibers instead of synthetic fabrics — as it will give your breasts some room to breathe and can feel more comfortable if you sweat. 

Do you have any questions on postpartum exercise and breastfeeding? Let us know in the comments below! And be sure to download Baby2Body for daily guidance on your postpartum journey, as well as nutrition and wellbeing coaching to give you the tools you need to do motherhood your way.

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