Calories Eaten Versus Calories Burned

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Whether you are trying to bulk up or slim down, understanding the relationship between calories eaten and calories burned is crucial, but figuring it out can be a challenge. A number of factors can impact that relationship, plus people burn calories at different rates, even while doing the same activities. If you want to master your weight, knowing the basics of how calorie consumption and calorie burning works is a must.

Calories Defined

A calorie is a unit of heat measurement. One calorie is the amount of heat needed to increase the temperature of a kilogram of water a single degree. In nutritional terms, calories are used to express the potential of food to create heat energy.


Calories and Weight

Your body uses a certain number of the calories in the food you consume for energy. Even while sitting still, you are burning calories to maintain normal body functions. When you move, you burn more calories, giving you the energy to complete the activity. If you eat the same number of calories that your body burns, then your weight will be stationary. If you consume fewer calories, you will lose weight, and if you eat more calories than your body needs, it stores those excess calories as extra weight.

Energy Storage

Excess calories are stored in fat cells as a reserve supply of energy. Fat is the most effective energy storage unit your body has. According to Dr. Linda Kennedy of Healthy New Age, every gram of fat holds nine calories (or nine units of energy). When you continue to eat more calories than you burn, your cells continue to build up those energy reserves in fat, and you will see the numbers on the scale creep up.


Burning Calories

Eating fewer calories than you need forces your body to turn to those energy reserves of excess calories to get by. Dr. Kennedy suggests that exercise is the best way to burn calories. Both aerobic and non-aerobic exercises such as weight training cause the body to burn more calories. When you exercise, your metabolism increases to compensate for the exertion. The body uses calories to support that metabolic increase and to repair muscle wear and tear caused during periods of exertion. The increased calorie burn extends past the immediate workout period. In fact, building up your muscles will increase the base demand for calories, since muscles require more energy even in rest.


Determining Your Needs

If you want to gain or lose weight, it is important to know how many calories your body requires. Unfortunately, there is no set rule to apply. Your caloric needs fluctuate depending on your activity level, age, current weight, gender and any number of medical conditions and treatments. You can, however, get an approximation of your caloric needs using online calorie calculators. These tools give you an idea of your caloric needs based on height, weight, age and activity level. Your doctor can also help you understand how any medical condition you have impacts your calorie burn rate. Once you know your base number, track your calorie consumption and adjust it to get the desired weight gain/loss effect.