running - will it affect milk supply?

[motomoto]

dd is 6 months and I want to start doing some serious running, 15-20 miles a week eventually. will this amount affect my milk supply?

It won't affect you at all! You have to be doing Olympic-type training for exercise to have any effect, and then you just get some lactic acid in your milk which baby might not like the taste of.

Get out there and go for a run! Just remember a very supportive sports bra!

Nooooooooo, I started running 4 weeks after birth and bf for 12 months. It did make me more tired mind and I've only got properly back into serious traning after finishing bf. I could manage 60 min steady runs but found it impossible to do hills or hard runs as I just didn't have the energy and blamed it on bf (but it couls have been laziness)

Trained for and did a half marathon when DS 7.5 months, no affect on supply, but needed to wear 2 sports bras! And needed to time runs for immediately after feeds. Wasn't possible to do this on the race day and felt my milk come in 15 mins into the race!!
Have fun