The 5 Biggest Factors Affecting Metabolism

If you've been reading about my 6 Pack Pursuit, you know that to lose weight, I first had to calculate  my basal metabolic rate (BMR) to figure out how many calories I could consume.

Let's define what I mean by BMR. I mean the amount of calories that a person's body uses for everyday functions like pumping blood, breathing, digesting, sitting, standing, walking, typing, and surfing the internet for pictures of fat Charles Barkley and skinny Charles Barkley. This excludes energy used for exercise like playing co-ed flag football, weight lifting, or running. So think of a "wake-up-go-to-work-come-home-go-to-bed" type of day. What factors come into play? Here are the big 5:

1) Age: Sorry Charlie, you get older and fatter for a reason. Metabolism slows down. Unless you have  more time to work out or slowly start to dislike delicious foods, you're screwed. Or, you know, if you get old AND stop playing professional basketball, you'll probably gain weight like Sir Charles here.

2) Weight: Moving more weight takes more energy, obvi. You'll hear about pretty overweight people losing 30lbs in a couple of months or enormous people losing 200lbs in a year without running hundreds of miles or hitting the weight room for 2 hours/day. When you weigh over 200 or in some cases 300lbs, getting up from the sofa or taking the stairs is no easy task. The obese have built up muscles to move that much weight so they're burning more calories by living normal lives. Consuming less than 3000 calories/day is more frequently the real challenge.

Tons of calories being burned here.

3) Gender: Women are much better at storing energy (aka fat) than men. Lower muscle mass, higher fat percentage. In fact, dudes shouldn't drop below 2-5% body fat while dudettes healthily bottom out at 10-12%. I'd bet Madonna was cruising below 10% in the picture of her in my previous post. Pretty manly looking ain't it? At least gals can carry extra weight and still look good.

Kim Kardashian, looking alright
with 25%+ body fat. 

4) Activity level: The hardest variable to gauge. How active are you? Do you sit at the same desk writing code all day or shuttle back and forth between the kitchen and tables of TGI Friday's? Are you an Apache warrior who hunts deer with a knife every day or a programmer writing code? Do you sit in a comfortable, boring, office chair or do you sit on a core-engaging fitness orb?  Chances are that the waiter, Apache warrior, and fitness orb sitter are burning more calories.

The squaws often teased
Geronimo for getting doughy
once he switched to hunting
with rifles. 

5) Height: If all other factors are the same, it takes more calories to move a lanky body just because of the distance blood has to travel and the mechanical disadvantage of moving long limbs. Don't get it? Compare torso rotations with a 25lb plate held to your chest and a 25lb barbell on your shoulders. You'll find the barbell to be more difficult. The length makes it tougher.

Manute. Bro. I'm telling you,
a gallon of milk and a dozen eggs
PER DAY. You gotta EARN
quads like these.

Stay tuned for the next post. Talkin' 'bout how to calculate your BMR.
LSF