What is Metabolism (and how do we get a better one)?


This word “metabolism” is thrown around a lot when discussing exercise and nutrition.

You know that if yours is too slow you might lack energy and gain weight.  But what exactly does this all mean?

Well technically “metabolism” is the word to describe all of the biochemical reactions in your body.  It’s how you take in nutrients and oxygen and use them to fuel every cell in your body to do what they do.

Your body has an incredible ability to grow, heal, and generally stay alive.  And without this amazing biochemistry you would not be possible.

Metabolism includes how the cells in your body:

  • Perform activities you control (physical activity and movement)

  • Carry out activities you can’t control (heart beat, healing, processing food and toxins)

  • Allow storage of excess energy for use later

As all of these processes work together as part of your metabolism you can imagine that they can work too quickly, too slowly, or just right. . . which is what is referred to as “metabolic rate”.

This is how fast your metabolism works and is measured by energy (otherwise known as calories) used or stored.

The calories you eat can go to either work (exercise and activity), heat (for biochemical reactions) or storage (the leftovers stored as fat). Ideally the amount of energy you consume will be the amount of energy that your body uses for activities and as heat.

There are a couple of different ways to measure metabolic rate.  One is the “resting metabolic rate” (RMR) which is how much energy your body uses when you’re not being physically active. The other is the “total daily energy expenditure” (TDEE) which measures both the resting metabolic rate as well as the energy used for “work” (e.g. exercise) throughout a 24-hour period.

What affects your metabolic rate?

Well . . . a lot of things!

The first thing you may think of is your thyroid.  This gland at the front of your throat releases hormones to tell your body to “speed up” your metabolism.  Of course, the more thyroid hormone there is the faster things will work and the more calories you’ll burn. But this isn’t always a good thing. Those with an over active thyroid will have symptoms including weight loss and anxiety because their body is on overdrive.

But that’s not the only thing that affects your metabolic rate. Your size matters in this equation too.

Larger people have higher metabolic rates, because you are moving more body weight around in a day. What your body composition – if you are made up of more fat tissue or muscle tissue – is crucial also.

As you can imagine muscles that actively move and do work need more energy than fat does.  So the more lean muscle mass you have the more energy your body will burn and the higher your metabolic rate will be.  Even when you’re asleep in bed at night.

This is exactly why weight training is often recommended as a part of a weight management program.  Because you want muscles to be burning those calories for you. Aerobic exercise also temporarily increases your metabolic rate, because you are burning fuel to move. This affect isn’t as long lasting though.

The thing is, when people lose weight their metabolic rate often slows down which you don’t want to happen.  So you definitely want to offset that with more muscle mass.

What you put in your body matters too – the type of food you eat affects your metabolic rate. Your body actually burns calories to absorb, digest, and metabolize your food.  This is called the “thermic effect of food” (TEF). You can use it to your advantage when you understand how your body metabolizes foods differently.

Fats, for example increase your TEF by 0-3%; carbs increase it by 5-10%, and protein increases it by 15-30%.  By trading some of your fat or carbs for protein you can slightly increase your metabolic rate. Another bonus of protein is that your muscles need it to grow.  By working them out and feeding them what they need they will help you to lose weight and keep it off.

And when talking about metabolism, we can’t neglect the mind-body connection. There is a lot of research that shows the influence that stress, sleep and outlook on life have on metabolic rate.

This is just the tip of the iceberg when it comes to metabolism and how so many different things can work to increase (or decrease) your metabolic rate.

If you feel like you are struggling with energy, injury healing, or weight management due to a sluggish metabolism there is much more individualized tips we can offer. Our Wellness Coach can help you get a clear perspective on where you are, a vision for where you want to be and a plan to get you there. Education, accountability and encouragement go a long way in cracking the metabolism code. Learn more by clicking the link below.