Weight loss is a combination of many factors. Yet our body's metabolism is the taskmaster, controlling what we take in and how we utilize the energy that is created. Specifically, metabolism is the process by which our bodies combine nutrients with oxygen to produce the energy needed to maintain normal bodily functions. This energy is measured in calories and calories are basically considered the fuel for our bodies. By extension, the more energy we expend, the more calories we burn, and thus the more weight we can lose. Your metabolism is determined by gender, age, amount of muscle you have compared to body fat and the amount of exercise you do on a regular basis. Male's rates are higher than females because of testosterone.
If weight loss is your goal, your efforts will be greatly facilitated by increasing your metabolism. When our main source of energy (glucose) depletes, the process of metabolism turns to fat stores (body fat) for its primary energy source. On the other hand, when our supply of blood sugar is too high, the process of metabolism stores excess "energy" by converting it into body fat causing the weight scale to move in an upward direction.
If you want to increase your metabolism, you should first consider all the factors involved. Sex, age, muscle tissue, weight, activity level, and your current physical condition.
Resting Metabolic Rate (RMR) is the number of calories you would burn if you were to do nothing for 24 hours. RMR is the minimum amount of energy required to maintain normal bodily functions (heart rate, breathing, normal body temperature, brain function, kidney function, and so on). To give you an example, a top notch, physically fit, professional athlete would burn approximately 1800 calories while undergoing normal, everyday activities, while a sanitation worker would burn approximately 1000, and a bed-ridden person would burn approximately 450. Eating at frequent and regular intervals will increase and speed up your metabolism. It is important to never skip a meal or go on any type of starvation diet. You should always eat healthy snacks between meals. The idea is to eat frequently to prevent hunger pangs (and the resulting binging) and to keep your energy levels consistent, which in turn will increase and speed up your metabolism. It is often believed among dieters that the fewer calories consumed, the faster the weight loss. Although this seems to make sense logically, it is actually incorrect as our body strives to store fat when it feels threatened. Efficiently, our bodies were designed with a survival mechanism, which is triggered in cases of deprivation and disaster. This famine mode sends a signal from our brains to conserve and slow down functions, in effect, decreasing metabolic rate. Because of this mechanism, it is easier for the body to store fat. Since muscle tissue burns a higher number of calories, the less muscle we have, the lower our metabolic rate.
To illustrate this point, an experiment was conducted with two brothers who were approximately the same height, weight, and body type. The first was instructed to eat 3 square meals. The other was told to eat the same quantity and type of food, but split up into 17 little snacks. Over the course of a 3-month study, the first brother, who ate normally, maintained his body weight and his elevated blood pressure remained constant. The other brother, who consumed his nutrition as regular little snacks, lost weight, slept more soundly, experienced a positive mood change, and had the added benefit of decreased blood pressure. The practical application of this study is to maintain a proper balance between frequency and portion.
In an effort to increase metabolism, eat several smaller meals throughout the day, and enjoy a few healthy, low calorie snacks in between. If you monitor the calories of the food consumed, this method of eating not only promotes weight loss, it increases your chances of prolonged success as you will feel more satisfied, both physically and emotionally, as you are maintaining your blood sugar levels.
Remember: in order to lose weight, you must reduce both the size and calories of your meals to compensate for the additional calories of the snacks. In an effort to lose weight rapidly, many people choose to severely reduce their caloric intake. This is a common mistake, which has several negative consequences, including a reduced rate of metabolism, and an imbalance of the thyroid and hormonal functions. When this occurs, weight loss becomes very difficult.
After proper food consumption, exercise is the key. When we exercise, our bodies require more energy (utilizing more calories) and our metabolism increases in order to supply it. However, most of the time, we are not all that active, thus an increase in metabolism would greatly aid us in our weight lose endeavor. The goal for many is to simply increase resting metabolism so we can burn more calories while we are working or resting as it is very unusual in today's society to have the opportunity to exercise throughout the day (those who do, rarely need to diet).
Metabolism is strictly defined by the Dictionary of Sport and Exercise Sciences as the "chemical changes that utilize energy and result in tissue and compound building (anabolism) or breakdown of substrates and release of energy (catabolism)." From this definition, we can explore how exercise and strength training can influence metabolism. There are three ways strength training can increase metabolism.
- the workout session itself
- the post-training oxygen consumption following exercise
- the addition of lean muscle mass.
If you are interested in body composition changes such as weight loss, you should train at 60 to 80 percent of your one rep max weight. The metabolic rate is higher at increased loads, thus causing a greater number of calories utilized. It has been proven time and time again that properly performed high intensity strength training stimulates the development of muscle mass, which in turn will alter metabolism in two different ways.
As mentioned earlier, resting metabolic rate is increased when one gains muscle mass. While the energy expenditure per pound of lean body mass does not change, the addition of more muscle mass means higher energy expenditure or increased metabolism at rest. Second, the more muscle mass an individual has the greater the post exercise oxygen consumption. When strength trained individuals were compared to non-trained individuals, there was no difference in post exercise oxygen consumption per pound of muscle. However, since the strength training individuals have more muscle mass, they burn more calories during the post exercise period.
There are several factors that influence the excess post exercise oxygen consumption (resynthesis of creatine phosphate in muscle, lactate removal, restoration of muscle and blood oxygen stores, elevated body temperature, post exercise elevation of heart rate and breathing, elevated hormones). In one study researchers examined the post-exercise oxygen consumption of strength training exercise to increase metabolism. Metabolic rate was measured for nine subjects after 40 minutes of cycling (80 percent of maximal heart rate), 40 minutes of circuit training (50% of individuals' 1 RM x 15 repetitions for 4 sets), 40 minutes of heavy resistance lifting (80-90% of 1 RM x 3-8 repetitions x 3 sets), and a control interval. All forms of exercise increased the metabolic rate immediately after exertion. For circuit training and heavy resistance lifting, the metabolism increase was also significant 30 minutes after exertion. The absolute total increment in caloric use after exertion was comparable among circuit training, heavy lifting, and cycling. However, cycling alone was far less than both forms of weight training. In any case when one actually examines the energy cost or calories burned during the post-exercise period it is relatively small. Some researchers have commented that the post-exercise effect is sufficiently small and that it does not have a major role in the control of weight loss by itself. However, if you combine the entire exercise session with proper diet, weight loss and an increase in metabolism can be substantial.
The other factor to consider with the post-exercise is the fuel that is utilized. Strength training exercise tends to burn/utilize carbohydrate during the actual training session. However, after a workout more fat is burned to meet the energy demands of your body. The more carbohydrate burned during an exercise period, the more fat burned after exercise. The higher the exercise intensity, proportionately more fat will be burned during the recovery (resting) phase. Recent research at Colorado State University examined the effect of a resistance training session on post-exercise energy expenditure and resting metabolic rate, concluding that strenuous strength training can elevate metabolic rate for extended periods, and that this increased metabolism is due to the oxidation of body fat. Strength training increases energy expenditure during a training session. The high intensity or anaerobic nature of strength training indicates a higher utilization of carbohydrates during a training session. During the post-exercise recovery period, energy expenditure is elevated for a period ranging from two to fifteen hours. The increased energy demands are obtained by burning more calories, and a good portion of those calories are coming from stored fat. The addition of muscle mass on an individual will cause an increase in the number of calories that are utilized at rest.
So it is comforting to know while one is exerting themselves through a high intensity workout, that the hard work will result in an increase in metabolism that continues to burn calories hours after a workout.