Articles
Metabolism
Metabolism is your body's idle energy use. That is, the energy that is used just to stay alive. It is the constant and continual energy consumption that maintains every living cell in our body. Our cells are using oxygen to aid in the energy producing process with one of the by-products being carbon dioxide. By analysing the ratio of oxygen use to carbon dioxide produced, we can determine what fuel the cells use to generate the energy, whether it is carbohydrate or fat.
Order of Energy Usage
First we burn the kilojoules in alcohol. Then we burn the carbohydrate and if there is a high intake of alcohol or carbohydrate, excess energy will be stored. Next we burn protein and finally we burn fat. It is very easy to store fat if the intake of alcohol and or carbohydrate has been high. As well there is the added problem that alcohol and fat are more concentrated sources of energy.
Limiting total kilojoules and looking for a balance will ensure that with a reasonable level of physical activity weight loss can be achieved.
Low Kilojoule Diets
One must remember that over thousands of years of evolution, we have become excellent at storing fat. If we cut intake too much the body will feel a need to conserve energy from fat for future needs and will burn protein. Protein will be obtained from muscle. Less muscle will mean a slower metabolism. Crash dieting is not a good solution.
Fat Verus Carbohydrate in Weight Control
Fat was the bad word in the 80's and recently carbohydrate has been given bad press. It is true that carbohydrates are readily stored as fat if they are not used by the body. The problem is as food products have decreased in fat, they have increased in carbohydrate (sugar and starch). In fact, many low fat meals and drinks are carbohydrate saturated to compensate for the loss in taste that is associated with removing fat. In many cases, the total kilojoules can be similar to the full fat version. This means we should always look at the total kilojoule content and compare it to a like product when trying to lose weight. Eating more kilojoules than you are burning, regardless of source, will cause weight gain not loss.
Measuring Metabolism
A metabolism test can be performed by a specialist but may be very expensive without giving too much additional information. The resting metabolism accounts for 60-65% of your total energy requirement for the day. Digestion and movement and exercise make up the rest. It is thenpossible to determine how much you need to burn in additional activity and exercise in order to see a fat loss without a muscle loss. The assumption being that with increased exercise comes muscle growth. Losing muscle is very detrimental, as it will lower the resting metabolic rate. You should not lose more that .5 to .9 kg per week.
Can We Increase The Resting Metabolic Rate?
The best way is to increase metabolism is by increasing the number of cells that use higher energy. Heart and brain cells use the most energy but we can't change these. We can increase the muscle cells though and thereby increase the overall energy quota. By increasing their mass, the total energy used increases and an increase in metabolism will follow.
The percent muscle to fat can be measured using a DEXA machine or Dual energy X-ray absorptiometry although this is expensive. Knowing where you are starting with %muscle and fat can then assist with being able to measure an improvement at a later stage. It can also guard against loss of muscle through inappropriate low kilojoule dieting that will lower metabolism.
Increasing Muscle Mass Through Resistance Or Weight Training.
Resistance training or 'lifting weights' has been shown to improve muscle growth and increase the muscle cells energy requirement at rest, however it has been shown that undertaking this regime may not show measurable changes in metabolism until approximately 10 weeks of participation. This mode of exercise combined with regular aerobic training (which maintains cardiovascular fitness) has been shown to generate the best weight loss scenario. BUT it must be coupled with balanced eatling.
The Final Weight Loss
To lose weight in the end, input must be less than output. A slow metabolic rate means that more exercise may need to be done to achieve the desired results. Don't be discouraged as their is a formula that will work for you of a level of kilojoules to eexercise. It is best to see a dietitian to determine this.
Added to site on : Friday, 30 July 2004