I lost two pounds since last week's weigh in, but I also gained two inches overall? My exercise has been purely aerobic, not muscle building. What gives?

Where did you gain those inches?

It could be bloatig due to water retention form hormones, salt intake, stress or a number of things. There is also a great thread on here about how we lose fat and the fact water rushes into the empty cells to hold a place for the fat before the cells are flushed.

You can build muscle through arobic exercise. Remember you are supporting 166 pounds on your frame as you exercise. You migh be also getting adiquet protien whereas before you might of had too little (especially if you were on low fat). That added protien could be used to rebuild muscle damag4e from past diets.

Typically when you build muscle though you don't lose weight, you lose inches. This is because a pound of muscle is far more dense then a pound of fat. You might try adding some resistance exercise to help build lean mass. The improved density makes for better circulation. With a higher lean mass metabolism is higher, more carbs can be processed from exercise, and cellulite is decreased.

Thanks for explaining and advising.

I wasn't on any kind of diet prior to starting atkins. i gained tons of weight during my pregnacy (license to eat, or so i thought) and just haven't lost it. i weighed 145 when i got preggers but that was about 15 pounds more than i weighed the year before. (gained the freshman 15 during my first year of marriage.) i want to get back to my fightin' weight of 130, which happens to be the weight where i can fit into my large and pricey wardrobe. (it's economic too.) but my biggest reason for wanting to loose is health. my BP shoots up several times a day, due to parenting my high needs toddler. my heart rate is waaaay too fast too. (it was clocked at 184 bpm while on the elispser today.) i need to build endurance and strength before i can ramp up my exercise routine to truly have major health benefits.

to answer your question, i gained inches in my thighs and waist. waist may very well be water retention and "fecal" retention. (TMI!) thighs are probably from swimming laps using flippers.

thanks again.