Running/exercise groups in Brooklyn?

Hi!  My name is Jennifer and I just moved to Brooklyn from Chicago.  I have let myself go for way too long and am looking to get back into exercise but need some encouragement.  Would love to have a few or even one person that is looking for the same thing.  I enjoy running, yoga and weights and am in my mid thirties.  I feel like I would have more success in reaching my goals if I could work out with someone in a similar situation who lives close by.  Any takers?