calories are like gas for your car. nutrients are more like wiper fluid, oil, wipers, drive shafts, steering wheel and column, pistons, spark plugs, tires and that ilk. while you need the nutrients there, if you don't have the energy to make it go then it's not going to perform the function that makes it what it is. vitamin a and fiber aren't a fuel that your body can use to make your heart pump and circulate your blood and all of those other fun things that keeps your body alive and working. while 1200 might be a nutrient minimum, many people need more calories than that to perform those basic body functions. when your body doesn't get the calories it needs, it starts to make cuts. which means that since fat doesn't burn any calories, but muscle does, when there are not enough calories coming in to cover your expenditures [and this is a chronic, over time thing, not a one or two days here or there], you start to burn muscle. the less muscle you have, the fewer the calories you burn. think of your basic monthly expenditures. if you make 4000 a month, having rent of 1000 isn't a big deal. but if you were only bringing in 1500 a month, that 1000 a month would be a bigger burden. and if you suddenly dropped to that 1500 a month and your biggest expense is rent, one of the first things you would look into was finding a place with lower rent. your body does the same. when the intake is so far below the output, the output has to go down. and we really have no idea what corners your body is cutting to reduce the amount of that deficit. now when you have a lot of weight to lose, having a larger deficit between input and output is fine. you have a giant calorie bank in all that stored fat. and the more weight you lose, the less energy you spend hauling it around, so even if you were still eating the same amount as when you started. your calories deficit has decreased. but if you exercise more then that bumps up your output, so you need to eat more so that you maintain that deficit in that sweet spot. because if you cut too many calories, then your body starts doing those funky expenditure saving measures. and at the extreme end of that is that people who have been put on starvation diets tend to put back on all the weight they lost plus about ten percent if they have the opportunity.
Exercise (resistance training) may bring about an increase in protein needs; --most other nutrients would not need to be adjusted above the normal recommendations.
1200 calories could be too few to function on a day to day basis. One begins to feel tired, no energy, excessively hungry--not able to dedicate "full intensity" to the daily workout or just living 24/7. When the person increases calories, they start to burn more calories because they feel so much better. So for some; eating more ends up resulting in a greater weight loss. So cutting out too many calories, for a long time period, can be detrimental to weight loss for some people.
First as Ivylass said, exercise burns calories. Yes, if you are trying to lose weight you want to burn more than you eat. But if you eat too few calories compared to the amount you are burning, your body reacts as if you are starving and to protect your life, slows your metabolism down. The last thing you want to do when you are trying to lose or maintain weight is to slow your metabolism down.
Next, exercise uses more nutrients than calories. Vitamins and minerals are necessary for the function of muscle and all the functions of your body. As you increase your exercise you increase your need for these nutrients.
As you are building muscle with exercise, your protein needs increase a bit.
These are all some of the reasons you need to increase your food intake as you increase your exercise.
Robin VA EST
Pounds lost: 79.6
Fitness Minutes: (35,434)
6,533 11/9/13 6:17 P
I understand that 1200 is the recommended minimum daily calorie intake for an adult woman... because it seems to be a number that gets us all of our nutrients...
But here is my question...
If your body needs a set amount of nutrients that does not change if you exercise, and you reach those nutrient levels... why eat more? It is really nutrients we are after in that 1200 calories, right? If exercising doesn't increase the nutrient needs - why HAVE to eat more? How will your body go into starvation mode if it got all of those nutrients?
Challenges for the rest of 2014 (from 9/1): Burn 3000 calories/week with DDR ST 90min/week 10% body weight lost by 1/1/15 Complete True Beginner, Core, Recover, and Cardio on DailyBurn Exercise at least 10min/day for 100 days this year
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