A common myth and reason why many new mombods don't exercise is the idea that exercise will lower or change their milk supply. Let's bust this myth together!
Part I: Milk Composition. Here's the gist of one study completed by Lovelady (amazing name, right?) in 2013 - breast milk samples were taken before, 10 minutes after and 1 hour after 30 minutes of aerobic exercise. These samples were compared to a sedentary group of breastfeeding moms. Samples were analyzed for immunoglobulin A (IgA), lactoferrin (a protein with antibacterial effects for infants) and lysozyme (an antimicrobial enzyme that's part of our immune system) concentrations. The result? There were no significant differences between the exercise and rest groups. Additionally, there were no significant differences in breast milk composition before and after exercise.
Part II: Milk Supply. In 2012, Daley et al. completed a meta-analysis of RCTs (randomized controlled trials) - fyi, this is the gold standard in the research world - and found that mothers can exercise and breastfeed without any detriment to the growth of their babies. They compared four studies and consistently saw that maternal exercise does not significantly impact infant growth. We are only concerned about milk supply if the baby isn't adequately gaining weight.
Research shows that mothers who participate in a moderate-intensity exercise program had improved cardiovascular fitness and saw no significant changes in amount or composition in their breast milk.
A few tips for safe exercise:
Feeling a little lost on where to start? Let's talk!