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Counting Calories for Weight Loss


Undoubtedly, anyone who has attempted a fitness program with the purpose of losing weight has felt frustrated because the volume of work put in never seems to equal the amount of weight lost. There is a very simple explaination for this phenomenon: It all comes down to physics. There is a principle of physics called the law of thermodynamics. This basically states that energy (calories) can be stored or used. However, the calories that are put in will be of the same value when they are used or burned through exercise. Essentially, this is how weight gain and loss occurs. If more calories are taken in through the diet than are burned, weight is gained. Conversely, if more calories are burned than are taken in, weight is lost. Weight is maintained when the two are equal.

Practically speaking, this seems oversimplified. The problem is that it tends to be far easier to take in calories than it is to burn them. For example, one M&M candy holds the same number of calories that it takes the average person to walk the length of a football field. This means that about 17 M&Ms would demand walking one mile! To help you put this into perspective, we will help you do some math to more accurately estimate the difference between what you take in and what you burn. It will also help you create more realistic goals and expectations for your weight loss efforts through exercise.

It takes 3,500 calories burned to lose one pound of fat. This seems like a relatively large number, but it should be doable considering how hard exercise is, right? Wrong. Unfortunately, our bodies do not burn calories that fast. Below is a list of some common exercises and their net calorie values. Keep in mind that net calories burned means it is above and beyond the calories you would burn just sitting there thinking about exercising instead of actually doing it. The good news is that if you are doing weight-bearing exercise like walking or running, the more you weigh the more calories you will burn. This is due to the fact that you are moving your entire body weight against gravity. Activities like biking or swimming do not require moving the body weight against gravity, so the values are about the same regardless of a person’s weight. The flip side of this is that as you lose weight, it will take more effort and exercise to burn the same number of calories through walking and running. However, it should be a little easier since you will not be toting around as much weight.

To help you, we've provided a calculator for you to specifically determine your net calories burned for running or walking. As you calculate your net calorie burn, do not be discouraged. According to the law of thermodynamics mentioned above, if you burn 100 calories per mile walked, you would have to walk 35 miles to lose 1 pound of fat. Broken down this would be seven miles per day for five days. This does not imply that you should push yourself to crank out that many miles. It simply means that you should be patient and consistent with your program. Keep in mind that the math equation for weight loss takes both the caloric intake and the output into account. To get that difference of 3,500 calories, you can take in less while burning more. If you reduce calorie intake by 250 calories per day (about one bottle of cola) and burn 1,750 calories (walking about 3 miles, 6 days a week) you could lose one pound of fat in one week. In the course of a year, that would equal about 50 pounds! Smart and steady wins the race.

Net Calorie Burn for Common Exercises

  • Running: about 700 calories per hour (for a 150-pound person)
  • Walking (moderate pace): about 350 calories per hour (for a 150-pound person)
  • Biking: about 281 calories per hour at 10 miles per hour
  • Swimming (moderate pace): about 560 calories per hour
  • Stair climber: about 450 calories per hour
  • Weight lifting: about 250 calories per hour
  • Elliptical trainer: about 770 calories per hour (for a 150-pound person)

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