|
Science Library: The Physics of Weight Loss
Increasing Metabolism
By The Weight Watchers Research Dept. | 1/1/2005
 
When it comes to weight loss, it's all about calories. Burning more calories than the body takes in results in weight loss
and taking in more calories than are burned means a weight gain.
Metabolism is the number of calories the body burns and is made up of three components: resting metabolic rate, physical
activity and a small amount needed for food digestion. Increasing the body's metabolism has the potential to enhance weight
management because the number of calories needed each day would be higher (and so the amount of food needed to fuel that need
would be greater).
While many popular publications would lead you to believe otherwise, metabolism can only be boosted in two ways: increasing
the body's muscle mass and increasing the body's heart rate.
Muscle Mass
Losing some muscle mass is considered to be an expected part of weight loss because a
smaller body needs less muscle to move the body's weight around. Resistance (i.e., weight) training as part of a comprehensive
exercise plan can increase lean muscle mass in weight-stable individuals and minimize loss of lean tissue during weight loss.
While a few studies have demonstrated otherwise, most studies show that it is not feasible to decrease body weight and simultaneously
increase lean muscle tissue.1
A popular theory concerning weight loss, increased metabolism and exercise states that it is feasible to create a sustained
increase in metabolism through regular aerobic workouts. The studies that have evaluated this theory for scientific merit
have shown very mixed results. The general finding for studies done in humans is that, if this phenomenon exists, the impact
on overall metabolism is very small.2 Further, there are no studies that have directly linked the "after effects"
of exercise with significant weight loss.
Heart Rate's Impact
A person's heart rate has an impact on metabolism – the higher the heart
rate, the more calories burned. Stimulants, whether from a prescribed medication, dietary supplement, or a caffeine-containing
beverage, all work to increase the heart rate and fire up the nervous system.
In a controlled study that looked at giving stimulants, including amphetamines or a placebo, weight loss was greater with
the stimulant because heart rate and blood pressure were raised and food intake was decreased as a side effect of being "hyper."3
Most dietary supplements and herbal compounds that are sold over the counter to promote weight loss contain stimulants,
though at a lesser strength than that found in amphetamines. These products are often marketed as having "fat burning" properties,
which are achieved because they increase heart rate and blood pressure and decrease appetite. They can work, but they do so
at a cost to the body. Negative side effects include insomnia, nervousness, anxiety and, in extreme cases, death.
Increasingly, some of these products (including the ones that were most effective, like fen-phen and ephedra) have been
banned because of their negative side effects.
Ways to Boost Your Metabolism
- Eat Regularly - Eating 5-6 small meals throughout the day will give you energy throughout the day--helping
you to burn calories. Whereas, calories eaten during larger meals tend to get stored as fat.
- Maintain a Balanced Diet - Not only how often you eat is important, but your food choices are equally as important.
Nurture you body with the appropriate balance of protein and carbs.
Eating whole foods rather than processed food gives your digestive system a workout that burns calories.
For example: choose an apple over apple juice.
- Workout with Weights - Building muscle mass will replace stored fat. As you build muscle tissue your metabolism
increases.
- Don't Forget Cardio - You need to get that heart rate up and breathe a little heavier. Twenty to thirty minutes
of cardiovascular activity 5 days a week is recommended. Brisk walking or swimming are good. Or utilize exercise equipment
(exercise bike, treadmill, or elliptical trainer).
Making The Most Of Your Metabolism
Most of us have heard or read about the word metabolism. In literature, on the news and in many other
media outlets, metabolism has been described as slow, fast, idle, resting and active. As a result, all these descriptions
can become overwhelming, confusing and even seem contradictory. Hopefully, this article will help put some perspective on
what metabolism really means and how you can make the most of your metabolism.
Let?s start with the actual physiological
definition of metabolism. The textbook, Human Anatomy and Physiology by Elaine N. Marieb defines metabolism as the ?sum total
of all the chemical reactions occurring in body cells and reactions that transform substances into energy or materials the
body can use or store by means of anabolism (when the body uses food for energy) or catabolism (when the body uses food to
build or repair cells).? In other words, metabolism is the total amount of energy your body uses to maintain the processes
necessary for life, such as breathing, heart rate, body temperature and cell function.
When focusing on weight management,
metabolism becomes an extremely important factor. We all have a resting metabolic rate or RMR. RMR is the rate at which your
body uses energy (burns calories) when at rest, but aware. For instance, when watching TV, playing cards or talking on the
phone. The International College of Applied Kinesiology (ICAK) reports that in our resting state, we can potentially burn
up to 73% of our daily intake of calories. Your active metabolic rate is the rate in which your body is burning energy during
physical activity. During activity your body demands more energy, therefore your metabolism is temporarily increased in order
to meet your body?s energy demands.
The faster your metabolism during both activity and rest, the faster you will
burn calories. The faster you burn calories, the easier it is to maintain and lose weight. Seems pretty simple, however there
are some factors that come into play that unfortunately we are unable control.
- Genetics. Genetics plays a huge part in the speed of your metabolism. If your immediate family maintains a healthy
body weight easily, you are in luck. If they do not, you may have inherited a slower metabolism and may need to work a little
harder to sustain and/or lose weight.
- Age. Your metabolism naturally slows as you age mainly due to a loss in lean muscle mass. Most studies report that
between the ages of 25 and 30 your metabolism biologically begins to decrease.
- Gender. The very unfair, but true reality is that men naturally have a higher metabolism than women. Since women
are biologically built to bear children, their body fat percentage is higher to meet the demands of pregnancy. Therefore,
women usually have less lean mass, hence keeping a women?s metabolism at a lower rate.
However, there is
hope. The tips below can help you maintain and even raise both your resting and active metabolism rates.
- Participate in physical activity. As stated above, when engaging in physical activity, your body requires more
energy, temporarily increasing metabolism. Therefore, during that time you will be burning more calories than at rest. Physical
activity helps burn approximately 12% of your daily calories (ICAK). In addition, the European Journal of Applied Physiology
shows that metabolism remains elevated for several hours following physical activity, adding to the amount of calories burned.
- Increase lean muscle mass. Increasing your percentage of lean muscle mass is most likely the best way to permanently
increase your basal metabolic rate. The best way to increase lean muscle mass is by strength training. Lean muscle mass is
?energy-hungry?, meaning that muscle requires a lot of energy to be maintained, even at rest. One study found that one pound
per body fat uses an estimated five calories of energy per day compared to a pound of lean muscle mass that can burn up to
50 calories per day. Therefore, many journals, including the Journal of Applied Physiology have reconfirmed that strength
training boosts metabolism and increases lean muscle mass. As a side note, muscle weighs three times more than fat. Therefore,
if you are trying to lose weight and strength training, you may not see a big dip in how much you weigh. Do not focus too
much on the number on the scale. If your clothes are loose, chances are that you are decreasing body fat, increasing muscle
mass and losing inches.
- Always eat breakfast. Breakfast literally means breaking the fast. From the time of your last meal in the evening
to the time you eat breakfast the next morning may be 10-12 hours. When asleep, your body does not require much energy and
your metabolism is in an idle state. Eating breakfast or consuming energy helps jump-start your metabolism for the day. Research
actually shows that a good majority of individuals who do not eat breakfast are heavier and have slower metabolisms in comparison
to breakfast eaters. In addition, studies show that non-breakfast eaters consume more empty calories throughout the day leading
to potential weight gain.
- Eat five to six smaller meals per day. Eating five to six smaller meals a day as opposed to a big breakfast, lunch
and dinner will help your metabolism remain in constant working mode. It will also help maintain energy and insulin levels
throughout the day.
- Do not dramatically cut calories, crash diet or fast. Want to bring your metabolism to a screeching halt? If so,
skip meals, fast and try a crash diet or two. As a personal trainer, I have listened to many stories on how clients began
eating more and seemed to lose weight. This can be a reality. When you eat, your body uses the nutrients from the food as
energy to live. When you greatly restrict calories, your body will want to conserve energy and therefore slow down your metabolism.
This is why many crash dieters will see initial weight loss, but may quickly regain the original weight and potentially more.
In summary, being aware of your metabolic rate will help you start a weight management plan, try to lose
those last few pounds and/or maintain a healthy weight throughout life. Living a healthy life with a good eating plan, a smart
exercise program and trying a few tips from a fitness professional can help you maintain and/or raise your metabolism.
|
