How does lifting weights and running influnce my Atkins?

I'm going to a gym 3 times a week, for 20 years now (and yes, during those years I've gained all my weight - but, I didnt gave up on "my" gym ) for the last 2 years Im running outside, for an hour or two, 5 times a week. During the running , I lost 35 pounds. then someone told me about Atkins, I got his book and doing it for 5 weeks.
On my first 2 weeks, I felt totally out of shape and out of energy, but finally, it started to come back and I can run more and my egergy is back.
I cant see any "new" numbers only the "old" ones, up and down between
195-190....
Any advise or explanation ?....I thank you all a lot!!!