Q: I really want to get back into running but is it true that an increase in exercise will decrease my milk production?
A: This is a very common concern of moms as they begin to resume their old exercise routine or try to initiate a new one. Sadly very little research has been done on the subject. One very small study conducted by Lovelady et al compared the milk production of 8 sedentary women against that of 8 highly trained women. The exercising women exercised an average of 88 minutes per day, burning an extra 700 calories a day. The results of the study indicated that the exercising women had a higher milk volume and milk energy output than those who were sedentary.
So what made this possible? The women who exercised also ate an extra 600 calories per day to make-up for the caloric deficit created by the exercise. Most of us do not find ourselves working out for 1.5 hours per day, we are lucky if we can squeeze in 30 minutes, 3 days per week. We also are hoping to lose some weight, all while maintaining a healthy milk supply. To accomplish this we need to ensure that our nutrition is fantastic - including plenty of protein and healthy fats - and that our fluid intake is even better.
The Institute of Medicine recommends that breastfeeding women (who are not exercising) eat at least 1800 calories per day to ensure proper nutrient intake. Calories burned through exercise may need to be compensated for with additional food intake. Current recommendations state that breastfeeding moms should lose no more than 5 pounds per month, any more than that and milk production may be affected. Look to your baby for signs that they are not getting enough milk and feed often to encourage your body to produce more milk.
