Sunday, October 25, 2009

A Discussion on Calories

When I started my blog a week ago, my thought was to only talk about my experiences as a competitor. But, my life involves so much more than that! So, I need to discuss this topic because it's so important for my clients and myself to understand....calories!! For the purpose of this entry, I'm going to refer to the average American who has a desk job, and does exercise 3 days a week at a light to moderate intensity.

I get this question all the time. "How many calories do I need a day to lose weight??"

Okay, so your body burns a certain amount of calories per day, regardless of how active you are. You can be lying on your sofa and do nothing else but breath and blink your eyes, and you are burning calories. The calories you burn here is your "basal metabolic rate" (BMR). Everybody's BMR is different depending on several factors like your size, and the amount of lean body mass you have. For example, a person who is 200lbs with 7% body fat is going to have a higher BMR than a person who is of the same weight and has 20% body fat. Just by having more muscle, a person's BMR is higher.

There are a lot of ways to calculate your BMR. You could go to an exercise physiology lab and have it measured. There are also calculations that exist where you can determine your BMR based on your lean body mass, and others that calculate it based on weight, height, and age. Finding out your lean body mass is really important in determining your BMR...age, height, and weight alone will be inaccurate for most elite athletes or those holding a high level of muscle mass. A good calculation for the general public to determine BMR is:

Women:
BMR = 655 + (4.35 x weight in lbs) + (4.7 x height in inches) - (4.7 x age in years)

Men:
BMR = 66 + (6.23 x weight in lbs) + (12.7 x height in inches) - (6.8 x age in years)

So, once you've determined your BMR, you have to factor in how active you are. This includes your job, sports, recreation, etc. This will add additional calories onto your BMR value.

The simple fact is that if you consume more calories than you burn, you will gain weight. If you consume less than you burn, you will lose weight. You will lose or gain muscle weight and fat. Lets talk about over consumption first...

If you consume more calories than you burn, you will gain weight. For the average American, usually this is not the goal. But for someone who is underweight, training for a bodybuilding competition, or in the off season for their sport, one may want to do this. However, one has to be careful that they are maximizing muscle gain and minimizing fat gain (both will happen, you can't have one without the other). Exercise that includes resistance training, overloading the muscle, will maximize muscle gain. Now remember, the more muscle you have, the higher your BMR. You will have to adjust your diet accordingly. Food that you'll need to eat are high protein, low fat foods such as chicken, egg whites, fish, complex carbs, etc. There will come a time when you've reached your goal with your weight or your lean body mass, and you'll need to maintain it or reverse it and cut down a bit like at the start of your season, or in prep for a bodybuilding/fitness/figure competition....

If you consume less calories than you burn, you will lose weight. Now this is usually the goal of most Americans. But, again, one has to be careful. If a person drops their calories below their BMR, or drops too low for too long, their metabolism will slow down. This is because they will likely lose a good amount of muscle mass, their BMR will slow down, and they will have to keep lowering their calorie intake. Now, you have a very low BMR, and your sick of "dieting" so, you decide..."the hell with it, I want to go to the cheesecake factory" and you proceed to have a meal that is 2500 calories if not more. The problem is is that your BMR is so low, it has no need for all those calories, so will store most of it as fat. Now, if your BMR wasn't so low...you would use more if it for energy and less fat would be stored. Make sense???

Moral of the story, DON'T drop your calories below your BMR...you may lose weight initially, but research does show that keeping your intake above your BMR will result in more permanent fat loss.

Thanks for reading!!

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