Jen Curtis
Breastfeeding and Exercise Q&A: Can I make a diastasis or damage my joints if I exercise while b
Q: Hi Jen, I'm looking for some advice... My post natal yoga teacher said that whilst breast feeding the pregnancy hormones remain in your system and as a result if you push yourself too hard you can still end up with diastasis recti and joint problems even if you didn't have them after the birth. Because of this I've only been doing gentle-ish exercise but I really want to get stronger, I have noticed my knees ache if I run for over 12km but don't know if that's the hormones or lack of strength! I don't have a gym membership so I'm thinking just quick workouts I can do at home like HIIT training or something. My little boy is nearly 1 so my body is very much recovered from childbirth/pregnancy but it's the breastfeeding thing that I just can't find any advice on... Do you reckon I can just go for it? (building up according to my ability)
Hi Anna - great question, I get asked this a lot, and you're right, the advice about exercise while breastfeeding is pretty lacking... and a lot of it is total garbage.
Your yoga teacher isn't totally wrong, but she's definitely gone a bit OTT with her message.
Remember, we have to hit a good balance when we advice women about exercise postpartum (or anyone really)... we don't want to throw the baby out with the bathwater and just do anything we want to do, or go straight back into what we were doing before, but on the other hand, there is such a thing as being TOO cautious. This can be just as bad as throwing caution to the wind and going bonkers because we can make women so fearful of doing any exercise that they just don't. Exercise is good for us - it's good for joint health, cardiovascular health, longevity, it prevents osteoporosis, diabetes, heart disease, obesity and depression. If our message is too restrictive or too cautious, we stop women from getting all these health benefits.
In addition, while there is a ton of information out there on the effects of exercise on breastfeeding; not many people are talking about the inverse relationship: the effects of breastfeeding on exercise.
What we do know is that breastfeeding affects your hormones. Estrogen and progesterone levels are high during pregnancy, and they plummet after giving birth and will only start to rise again when the ovaries start producing them once more.
In breastfeeding women, levels of estrogen and progesterone will remain low until they stop.

There's not an awful lot written about how breastfeeding affects exercise, but it is thought that breastfeeding affects our connective tissues and joints, making us a bit weaker and more prone to injury.
(On a side note, it often makes fat loss really hard, but that's a separate blog post).
HOWEVER, there is little proof to back this up. Anecdotally, I often work with breastfeeding women who have DR or pelvic floor complaints who find that it's really very stubborn. As soon as they stop breastfeeding, things start to get better very quickly. The same is true of fat loss. But this is not true for every breastfeeding woman, nor is it the same as research.
If we presume this to be true, what that would mean is that we might be a little more prone to "the big 3" of pre- and postnatal complaints:
Pelvic floor dysfunction
Diastasis Recti
Muscluloskeletal complaints i.e. back pain, hip or knee pain etc.
HOWEVER, let's talk specifically about your situation
You are a year postpartum, don't have and haven't had any pelvic floor dysfunction or diastasis recti. You've been exercising for a while now doing yoga and running. You are experiencing some knee pain after running longer distances. You feel ready to up the intensity of your exercise, but are concerned about causing damage.