Eat better, move more and keep an eye on your body composition to rev your metabolism and achieve the gains you so desire. Photo/FILE
By RAYMOND AKEYEE firstname.lastname@example.org Posted Tuesday, April 3 2012 at 00:00
Metabolism is one of the raging buzzwords on the fitness scene these days. Everyone has something to say about it, but not many of us actually understand how it works or the ways in which we can modify our eating and exercise behaviour in order to influence it.
Simply put, metabolism is the entire range of chemical reactions through which living organisms, such as ourselves, create the energy we need to sustain life from the food we consume.
There at least three important things that we need to keep in mind when discussing the subject of metabolism.
Basal metabolic rate (BMR)
This is the minimum energy requirement necessary to sustain life in a resting individual. It is the amount of energy your body would consume if you simply lay in bed all day, without any form of exercise or movement.
Experts estimate the average the average BMR for a healthy adult is about 2200 calories a day; the energy you need to simply stay alive. And this is where body composition comes into play.
Body composition is the term used to describe the different components that when taken together, make up your body weight.
Your body is composed of a variety of different tissue, including lean tissues — muscle, bone and internal organs — all of which are metabolically active, and fat or adipose tissue which is inert and needs no energy at all to sustain it.
One can easily determine his or her body composition in a gym setting through the use of a bioelectrical impedance machine, which works by sending a mild, imperceptible electrical current through your body.
Muscle readily conducts electricity while fat, being an insulator, resists it. The machine can thus use these differing properties of fat and muscle to determine your body composition.
One of the ways to ensure that you speed up your metabolism in order to lose weight is by working to influence your body composition through a combination of strength training and cardiovascular exercise, which we will look at more closely in a short while.
The recommended healthy range of body fat for men is between 15 to 18 per cent, while for women it is 22 to 25 per cent.
Unrestricted physical activity
This is the amount of exercise you expend though physical activity. Running, walking, attending aerobics classes and such other activities speed up your metabolism by increasing your energy consumption. It is important to note that a single kilogramme of body fat contains slightly over 7000 calories.
This is exactly why your body uses fat as a form of energy storage; it is an extremely effective form of energy storage. Well, this is great if you need to survive a famine, but it can be a problem if you are looking to shed a few pounds, unless you systematically increase your levels of unrestricted physical activity.
The mathematics is simple; all you really need to do is burn an extra 500 calories every day over and above your BMR. In one week this will amount to 3500 calories or at least half a kilogramme of weight loss.
Working with this method, it is also possible to set realistic and achievable weight loss targets. Based on your body composition analysis you can project how long it will take you to achieve your weight loss goals.
Thermal effect of food
The human body is essentially a biological machine, which converts the potential energy in our food into kinetic energy that enables physical work and movement.
Like all machines, however, a lot of the potential energy is lost through heat. In fact some experts estimate that out of every 100 calories we consume, only 20 calories are converted into work, meaning about 80 calories are lost though heat and other metabolic processes.
One of the ways in which you can use the thermal effect of food to enhance your metabolism is by paying attention to a scale known as the glycaemic index (GI), which measures how fast a food is likely to raise your blood sugar.
Low glycaemic carbohydrates are the ones that are digested slowly, releasing a consistent flow of energy into the blood stream. These sorts of carbs also require more energy to digest and process due to their high fibre content and are therefore best suited for weight management efforts.
High glycaemic carbs, on the other hand, are composed of simple sugars that are rapidly absorbed into the blood stream, precipitating a spike in your insulin levels, which in turn affects the body in a number of ways.
The moment your insulin levels are elevated as a result of ingesting high GI foods, your body stops metabolising fat and turns its attention to this excess blood sugar, which it mops up by encouraging its conversion into fat that ends up around your hips and waistline.
It also leads to energy imbalances where energy highs are followed by dips as your body mops up the excess blood sugar, in turn promoting cravings for more simple sugars.
This precipitates a vicious cycle that can ultimately contribute to the development of metabolic conditions such as type 2 diabetes.
Eat better, move more and keep an eye on your body composition to rev your metabolism and achieve the gains you so desire.
Raymond is a fitness consultant. To join the conversation on Facebook, search raymondonyango.com.