A big concern for women hoping to return to the gym is how her workouts may impact breastfeeding. The old school way of thinking was that if a woman exercised, the lactic acid that built up would result in a sour tasting milk.
In his chapter on breastfeeding and exercising in “Exercising Through Your Pregnancy,” Dr. James F. Clapp writes, “The concern that regular exercise during lactation alters the quality and quantity of the breast milk had its origins in the dairy science literature, which indicated that even modest increases in physical activity decreased milk production in cows.”
Because breastfeeding moms are equivalent to cows.
Other medical studies from the early 1990s reinforced this theory, however, Clapp writes, the findings were misconstrued and spin-off studies conducted by nutritionists found that “frequent, sustained, moderate- to high-intensity running during lactation did not impair the quantity or quality of human breast milk.”
Breastfeeding USA writers Jennifer Palmer and Sharon Knorr second these findings.
“A couple of small studies found no difference in immunologic factors after moderate exercise, but they showed a decrease in immune boosting proteins after exhaustive exercise,” they write. “Levels return to normal within an hour, and the impact on baby is unlikely to be significant.”
Losing weight while breastfeeding
Another concern for breastfeeding women anxious to return to the gym is whether losing weight will affect her supply.
Clapp, again, comes to the rescue. In his research, he found that women who continued to consume 1,500 calories or more per day were able to lose weight and continue meeting their infant’s milk needs.
Of course, every woman’s caloric needs are different and 1,500 calories is just an approximation. But Clapp’s research found that women who consumed fewer than 1,500 calories experienced a decrease in production and infant weight gain decreased as well.
“The threshold for this effect is when calories in are about 20 to 25 percent below calories out,” Clapp writes, adding that frequency and duration of feedings may also impact supply.
Assuming a breastfeeding woman consumes the minimum number of calories to keep up her supply, she may be curious as to which foods are the best to assure she and her baby are getting the appropriate nutrients.
In a BirthFit blog post, coaches encourage a postpartum woman to eat protein before working out and consume a carbohydrate, such as sweet potatoes, within 30-90 minutes after completing a workout.
It’s also important for a breastfeeding woman to continue taking prenatal supplements as well as iron, calcium, and a quality fish oil.
Disclaimer: Andrea Signor is a writer. She does not have any medical background or fitness certifications. She is a former journalist with an interest in weightlifting. Any woman interested in exercising and lifting in her pregnancy should consult with her medical team and fitness coaches.
Want more? Read part three of our series: Do’s and Dont’s for postpartum fitness
Missed Part One? Check out our tips for postpartum weightlifting here.