As a fitness specialist, I’m often asked about how exercise effects breastfeeding, from milk production and babies’ weight gain to whether the baby will accept the breast. There’s been a lot of research done on this topic, and I’ve provided the answers to some of the most common questions I’ve received here:
Does exercise affect milk supply or nutrient content?
No. The majority of studies have shown no difference in the volume or composition of the milk or babies’ weight gain. Although there was one study that showed a slight increase in milk supply for women who exercised regularly, there were too few participants for the results to be considered valid.
Does lactic acid increase in breastmilk after exercise?
If you are exercising at a moderate level of intensity, research has not shown any noticeable increase in lactic acid build-up. It’s important to note that if you are exercising at maximum intensity, also known as exhaustive exercise, then the lactic acid levels in the breast milk will increase somewhat. The lactic acid will remain in the milk for up to 90 minutes post-exercise. However, there are no known risks or harmful effects of babies consuming lactic acid.
Will baby refuse the breast after mom exercises?
Most studies have found no difference in whether the baby will accept the breast, even after maximum intensity exercises. In fact, Dr. Ruth Lawrence, who writes the breastfeeding guide for the medical profession, says that there is no reason to wait to nurse after exercising.
Here are some exercise guidelines for breastfeeding mothers:
- For your own comfort, you may wish to nurse before exercising and wear a good, supportive bra (especially during strenuous exercises such as running or jumping).
- Some babies don’t like nursing when the mom has been sweating (due to the salt on mom’s skin) so you may want to rinse your breasts or take a shower before nursing.
- If you regularly lift weights or do other exercises involving repetitive arm movement, and you develop plugged ducts, cut back and start again more slowly.
- Make sure to keep yourself hydrated throughout the workout!