Wednesday, April 08, 2009

Calorie Deficit

I'm going to try to keep track of my calorie deficits to see what's going on with my weight loss. I'm holding steady at having lost 2 whole pounds since starting South Beach. The last couple of times I did Phase 1, I lost about 6 pounds in the first week. I have a feeling the stagnation may be because I'm working out as well and possibly not eating enough.

According to the calculators, my Basal Metabolic Rate is 1641 calories. Basically that's how many calories I need to eat each day in order to stay alive and maintain my weight.

Figure in 45 minutes of swimming, at about 50 yards per minute, which burns 571 calories (not, unfortunately, the 740 calories SparkPeople says it does. That would be nice.)

So my calorie expenditure for today is 2212. To maintain my weight, I should eat 2212 calories.

Right now, with the food I've figured for the day, I'm going to eat 1497 calories.

Deficit = 715 calories.

I have a feeling that's too big of a deficit.


Rachel said...

a) I think you rock-- very impressed by your swim-a-thon success. :)

b) The rule of thumb I learned for a good calorie deficit to aim for (unless you're morbidly obese, which you clearly are nowhere near) is 85% of your caloric need. So it looks like you probably are a little low-- perhaps you'll feel better and stop plateauing on ~1880 calories instead of 1400.

Kelly said...

Rachel, thanks for the insight. You are my food guru. (By the way, according to BMI, I'm "obese". I don't think I look obese, but maybe I'm just deluding myself...If so, let me keep doing that. It's a happier place.)

K said...

Hi Kelly! I was procrastinating and remembered that you have a blog, so here I am. I just wanted to let you know that we are taught to take 500kcal off BMR for 1lb/wk wt loss or 1000kcal for 2 lb (although this is used less). That would put you at around 1600-1700kcal, basically where you are without counting the swimming. I don't know what "activity factor" your calculator used or if you used your actual wt or ideal wt which would also affect things. Also, BMI is/should be taken with a large grain of salt (or maybe a salt-free substitute) and is not a good indicator of health, fitness etc. (which you probably already know)