Like others have said, 1200 is a guideline. Everyone is different and it's based on things like activity level, body composition, gender, age, etc...

If you know your BMR (basal metabolic rate - what your body needs to just perform the basic functions), you can add activty to that to figure out your needs. But even then, it's only an estimate and it can change with the different types of activity, different types of food, different days in your cycle, etc. There are a ton of factors, so in may ways it's best to experiment, track and learn. If you try to figure it out down to the last calorie eaten or burned, you'll drive yourself nuts. Not only are the calculations a pain, but when the body doesn't react like it's 'supposed' to...it's frustrating (and it rarely does what we expect it to do when it comes to weight loss!!).


Another factor to consider is that most HR monitors over report calorie burn for women. I don't know if that's how you figured the 9500 calories burned, but that's something else to consider. In my case, 120 miles a week and my weight training puts me at a calorie burn of about 5000 calories a week according to my HRM, but I know that's not 100% accurate. I consider it a guideline and do my best not to try and eat all those extra calories (or at least, that's my story! ). I try to use that number, my BMR, my energy levels, my experience with my own body and my hunger as a guide for what I am eating. When I keep all these things in balance (and I avoid the call of my inner 'Fat Girl'), I do all right.