Up until 3 years ago, I exercised 3x per week with a trainer and then cardio for 3 days. I was eating more of a Body for Life program and could not lose those last 15 lbs. I also had a hard time keeping muscle. If I overtrained I would lose muscle and not fat.

I was always a sprinter and at that time beat some RPM times on the bike of Olympians who trained at the same gym (I was 38 and they were 25!!!) During that time, I never had stamina. 30 minutes of running would kill me. I dreaded the treadmill because of my lack of stamina. My lungs would burn and I would feel like crap after.

Well, I stopped training because of injury and work about 3 years ago. I still skied on the weekends and some very light biking and did some exercise tapes every once in a while.

I decided to start Atkins because I wanted to lose my stubborn weight, but I decided not to exercise to until I got close to 150. I have put on 12 lbs of muscle and lost around 25 lbs of fat.

Today I jumped on the treadmill for the first time in about a year expecting the worst. I ran for 35 minutes at 6.5 mph and felt great after. As a matter of fact, I don't think I think I ever felt this way, even when I was training in highschool....

What in the heck is going on here?Is this too good to be true? I am still eating between 20-35 gms of carb per day and about 1700-2000 calories per day.

Your thoughts are appreciated.