Weight Loss Program, Part 3: Exercise & Metabolism
Read the following pages/chapters in your text, Dieting For Dummies this week: Chapter 12, pages 143-153
It's important to understand that you're not "stuck" with the metabolism you were born with. In fact, you can change and control many things to increase metabolism. One of the main ways is through exercise. But, boosting your metabolism isn't the only benefit of exercise in a weight loss program - you'll quickly become acquainted with the other beneficial side effects of getting fit. You'll discover how to begin a balanced program of physical fitness, and the importance of fitting in aerobic activity, strength training, and stretching each week.
Topic outline for Part Three:
What are metabolism and metabolic rate?
Your body requires a minimum number of calories each day to maintain its vital functions such as breathing, maintaining your heartbeat, and keeping your brain working properly. This minimum number of calories simply to maintain your life is called basal metabolic rate, or BMR. The total number of calories you burn each day is likely to be much greater than your basal metabolic rate, however, unless you spend your entire day lying in bed without moving. Your BMR accounts for about 60-70% of your total daily caloric requirement. Several factors influence your basal metabolism, including:
- Age – BMR decreases with age
- Height – BMR is higher in those who are taller
- Gender – BMR is higher in men
- Body composition – BMR is higher in those with more muscle
- Environmental temperature – BMR is higher in extreme heat or cold
- Dieting – BMR is lower in chronic dieters on very low calorie diets
- Stress – BMR is higher under stress
Exercise also affects the total amount of calories you burn each day. The goal in any weight loss program is to keep your metabolism elevated through any of the factors that you can control. The bottom line is that people with a high metabolic rate burn more calories throughout the day compared to those with a low metabolic rate. And of course, to lose weight, you must burn more calories than you eat, so a high metabolic rate is in your favor!
Metabolic factors you can't control or change:
- Age - As we advance in age we gradually lose muscle mass, so our metabolic rate decreases. You can anticipate about a 2% decline in your metabolic rate every decade after age 20.
- Sex - Men naturally have more muscle mass than women, therefore they generally have a higher metabolic rate. You can't change your sex, but you can change your muscle mass.
- Height - Because tall people have a greater amount of body surface area to maintain, they have higher caloric needs, and thus, a higher metabolic rate.
Metabolic factors that you can control, but are difficult to change:
- Outside temperature - If you live in an area with an extreme environment that is bitter cold or intensely hot, you require more calories per day to keep your own body temperature normalized. That is, if you expose yourself to the elements frequently. If you stay inside in a temperature controlled environment, then it doesn't apply to you. However, don't spend the winter outside at the North Pole simply to lose weight!
- Stress - Don't add more mental and emotional stress to your life, although it does burn some extra calories. Physical stress on the body, such as pregnancy and growth, also increases your metabolic rate.
- Fidgeting - Although it sounds silly, recent studies show that individuals with higher levels of "spontaneous physical activity," or fidgeting, burn significantly more calories than non-fidgeters. These types of people tend to have trouble sitting still, do a lot of pacing and tap their feet and bounce their knees when sitting. Fidgeting can burn as many as 800 calories each day! That's another good reason to get your body moving as often as possible!
Metabolism influences you can control
Low-calorie dieting - A "quick weight loss diet" will significantly decrease your metabolism in 3 ways:
- Eating increases metabolism due to the energy required for digestion and absorption of the food. Skipping meals causes a decrease in your metabolic rate until you eat something. Skipping breakfast and lunch and eating a large dinner means missing out on two important chances to increase your metabolism and boost the number of calories you burn.
- Significantly reducing calories lowers the body's metabolism. Your body treats any reduction in food intake as an impending starvation situation and prepares itself by slowing your metabolism to conserve calories. The more drastically you cut calories, the more your metabolic rate drops.
- Losing weight through dieting alone without adding exercise depletes your muscle tissue stores. Muscle requires many calories each day to maintain itself. The faster you lose weight through dieting alone, the more muscle tissue you lose. Exercise prevents muscle tissue loss and adds muscle!
- Eating - The calories required to digest, absorb, transport, and metabolize the food that you eat can cause a 10% increase in your caloric expenditure each day. Every time you eat, your body's metabolism gets a temporary boost. So, one way to increase metabolic rate is to eat smaller, more frequent meals and snacks when you are hungry!
- Body Composition - You hear it over and over again, but the more muscle you have and the less fat you have, the more calories you burn each day. Every pound of muscle in your body requires 50 calories a day for maintenance. By contrast, every pound of fat only requires 2 calories per day to maintain. To lose body fat, devote a good portion of your exercise time to strength training. By gaining 10 pounds of muscle, you could burn 500 additional calories each day!
- Exercise - Exercise increases metabolic rate in two ways. The first is the actual number of calories you burn while doing the exercise. For example, a 5-mile run might burn 500 calories during the time you are actually running. A second elevation in metabolic rate occurs even after you have stopped exercising. Your metabolic rate could take as long as 12 or more hours to come back to your normal level after exercise. Higher intensity exercises that use large muscle groups such as your thighs and buttocks will result in a longer elevation in metabolism after you stop exercising.
To sum it all up, the best way to keep your metabolism elevated, and to burn more calories, even at rest, is to:
- Avoid rapid weight loss diets
- Eat frequent small meals or snacks throughout the day when you're hungry
- Add more muscle to your body through strength training
- Burn more calories through aerobic activity
1. Aerobic activity
What it is: Exercising aerobically means training with air or oxygen. It involves a moderate pace, and the goal is to increase your endurance gradually, and to work within your target heart rate range, but not to fatigue your muscles. Aerobic activity does not involve short spurts of energy. It is typically a long, moderately paced activity. If you gasp for air, chances are you are probably working anaerobically, or without a sufficient oxygen supply to the muscles. Examples of anaerobic types of activities are sprinting, football, weight lifting, and other "stop and start" types of exercises. The following list contains aerobic activities:
Types of aerobic activity
- Cross-country skiing
- Aerobic or "step" classes
Why aerobic activity is important for health and weight loss:
- After 20 to 30 minutes of sustained aerobic activity, your body begins to burn your fat stores for energy.
- Strengthens your heart
- Reduces blood pressure
- You can maintain a continued increase in metabolism even several hours after you stop
- Improves your athletic endurance
- Releases “feel good” hormones like endorphins and can reduce depression and improve overall psyche
How much aerobic acitivty should you do?
To develop aerobic fitness, you must work out for a minimum of 20 to 60 minutes three to five days a week. Remember that if you do not exercise regularly, start out at the low end of these numbers and gradually increase the time and number of days you spend exercising. Choose an activity you enjoy that uses your large muscle groups, such as your thighs and buttocks.
During your session, work within your training heart rate:
Training Heart Rate = (220 - your age) x (.55 to .85)
Example for a 30 year old: (220-30)= 190 190 x (.55-.85) = 105-160 beats/minute
2. Strength training
What it is: Strength-training, also known as resistance training, is an anaerobic activity that is quite different from an aerobic activity. With aerobic activity, your goal is to keep a moderated pace and increase your athletic endurance. With this anaerobic activity, your goal is to cause fatigue to your muscles with harder but shorter bursts of energy in order to cause a continual increase in muscle mass and muscle strength. Strength training involves overloading or placing a stress (through weights or resistance) on the muscle until it can no longer lift the resistance using proper form. The muscle eventually adapts to greater levels of stress, and you must continually increase the amount of resistance you use when the a strength training workout is no longer difficult.
Types of strength training:
Why strength-training is important for health and weight loss:
- Muscle strength enhances most athletic activities, such as running, cycling, climbing, swimming and team sports.
- It reduces the risk of injury to joints and ligaments by providing them with extra support.
- The more muscle you have, the more calories you burn everyday, even at rest.
- Reduces risk of osteoporosis.
- Helps you look lean and toned. Have you ever watched a running event such as a 10K, and noticed all the flabby thighs jiggling around? While these runners may have great cardiovascular and aerobic endurance, they're probably not spending much time in the weight room to keep their muscles strong and toned.
(Note to women: You will not get huge like a man from lifting weights unless you take steroids or testosterone. You don't have the hormones in your body that cause such changes, but you will get toned and look lean.)
How much strength training should you do?
The American College of Sports Medicine recommends strength-training two to three days a week. Work up to two to three sets of 8 to 12 repetitions for each major muscle group:
- The biceps (front of the arm)
- The triceps (back of the arm)
- The shoulders
- The chest
- The abdomen
- The upper and lower back
- The quadriceps (front of the thigh)
- The buttocks
- The hamstrings (back of the thigh)
Allow at least 48 hours of rest between sessions to let your muscles recover. If you're new to strength training, consider hiring a certified personal trainer for at least the first couple sessions so you can learn proper technique and reduce your risk of injury. Some of the better-trained personal trainers have certifications from The American Council on Exercise (ACE) and The American College of Sports Medicine (ACSM).
Important: Include a warm-up to get your muscles warm and ready before any type of exercise. You can warm up by walking or light jogging in place for five minutes. Be sure your warm-up is moderate and does not exert you too much.
3. Flexibility and stretching
What it is: Stretching to improve your flexibility is important to improve your range of motion for the various activities you do. It will also decrease your risk for exercise-related injuries such as muscle strains and back and knee problems. It also helps relieve stress, improves circulation, and enhances muscle tone. The American College of Sports Medicine recommends that you stretch each of your major muscle groups a minimum of two to three days a week. Be sure to hold each stretch without bouncing for 10 to 30 seconds. The best time to stretch is after your warm-up when your muscles are loose, warm, and limber.
Try the following complete exercise plan:
- 5 minutes of warm-up (walking or light jogging in place)
- 5 minutes of stretching
- Aerobic or strength training exercise itself
- 5 minutes of cool down (similar to your warm-up, but even less intensity)
- 5 minutes of stretching
If you're still skeptical, review further why exercise is a critical component in weight loss:
- Increases Calorie Burning - Both aerobic activity and strength training increase the number of calories you burn both during and after exercise.
- Strength-training is especially important in increasing the calories you burn at rest by adding more muscle to your body.
- Protects Against Muscle Loss and Adds Muscle - Some studies show that the weight you lose from dieting alone is 75% fat and 25% muscle. You want to lose as little muscle as possible to keep your metabolism elevated. Exercising regularly with strength training can prevent the muscle loss associated with dieting and can keep that metabolism running strong!
- Helps You Eat Less - Exercise slows digestion and keeps you feeling full longer. It also helps maintain normalized blood glucose levels so you feel less hungry.
- Improves Self-Esteem- When you start feeling better about yourself and notice the positive psychological and physiological benefits exercise brings, it becomes easier and easier to stick with a weight-loss program.
- Helps Maintain Lost Weight - Research shows that the most critical factor in determining whether a person maintains lost weight is whether he or she continues to exercise regularly.
Important final note: Have your body fat tested before you start your diet and exercise program. Using the scale as a guide for your success can be very misleading. Muscle tissue weighs much more than fat, but it is denser, leaner, and smaller than fat pound for pound.
For example, an experienced body builder who weighs 230 pounds and is 5'11" looks a lot different than a guy with the same measurements who's a couch potato. The first guy has more lean body mass and less fat. So, he's leaner and healthier, and visually, his proportions appear just fine even though his weight is the same as guy number two. As you increase your exercise and your muscle mass, you might actually gain some weight, but you will probably decrease your body fat percentage and become leaner and thinner. The scale can be a very ineffective tool for measuring your success. Be sure to pay attention to how you feel and how your clothes fit.