Metabolism and Nutrition

Metabolism is a complex science and without a scientific background most of us are unable to understand it fully. However, if you want to build muscle you should have at least some knowledge of the subject in order to appreciate the importance of good nutrition.

Metabolism is the term used to describe all of the biochemical reactions and processes that take place in the body. There are many scientific explanations but put simply metabolism is the rate at which you burn energy or calories.

There are many different elements that affect your metabolism:

Age – metabolism slows 5% per decade over 40 years old, meaning you need to eat less or workout more to stop putting on weight.
Sex – men burn more calories at rest than women.

Lean body mass – the more muscle you have the higher the metabolic rate tends to be.
Stress – stress can lead to a slow metabolism, plus people tend to over eat when stressed.
Activity level – more active people tend to have a higher metabolic rate.
Hydration – not having enough water in your body can slow down your bodies processes.
Genetics – some people just have slower metabolisms than others.

Speeding Up Your Metabolism

If you have ever in the past blamed your weight on your metabolism then today is your lucky day. Because it is possible to speed up your metabolic rate and improve your fat burning capabilities.
The main method is by exercising. You should undertake both aerobic and weightlifting. The aerobic exercise burns calories in the short term while weightlifting increases muscle mass to boost your metabolism in the long run. Metabolism can be increased for as long as 48 hours after a bout of intense exercise.
Also it has been shown that 1lb of muscle mass burns 35-50 calories per day while 1lb of fat burns as little as 2 calories per day. Therefore you see how a little change in your body composition can magnify changes in your diet by burning more and more calories.
The second way to speed up your metabolism is by eating more often. By eating smaller more frequent meals throughout the day you can have your metabolism running in high gear through the entire day.

Calculating Your Metabolism

There are two main methods for calculating your metabolism. They are RMR – resting metabolic rate and BMR- basal metabolic rate. These are essentially one and the same and are interchangeable. The only difference is that your BMR should be calculated under much more controlled and stringent circumstances. The result of both will give you the basic amount of calories your body needs just to function throughout the day. For example just to keep your heart beating and lungs breathing and your body functioning properly.

Harris-Benedict equation for BMR

Men (13.75 x w) + (5 x h) – (6.76 x a) + 66
Women (9.56 x w) + (1.85 x h) – (4.68 x a) + 655
Mufflin equation for RMR
Men (10 x w) + (6.25 x h) – (5 x a) + 5
Women (10 x w) + (6.25 x h) – (5 x a) -161
W=weight in kg
H= height in cm
A=age

You can use either of the equations, however I prefer the BMR.

In order to work out how many calories you need for your activity level you need to take the figure you worked out above and multiply by activity factor.

Exercise 1-2 times per week BMR x 1.2
Exercise 2-4 times per week BMR x 1.4
Exercise 4-6 times per week BMR x 1.6

The final figure is then the amount of calories you should consume in a day. If you want to lose weight you should eat fewer calories than this number. If you want to gain weight you need to eat more calories than this number.

Nutrition and Metabolism

Good nutrition plays a vital role in maintaining metabolism at optimum levels. The body needs a wide range of nutrients to function optimally and even a slight deficiency of one vitamin or mineral can slow down metabolism and cause chaos throughout the body.

Maintaining a fully functioning metabolism is therefore critical for the athlete or strength trainer. Adhering to the principles of the food pyramid is a great start in achieving the correct balance.