Aerobics Frequently Asked Questions Welcome to the text version of the Aerobics FAQ. The full version (and latest update) is available in HTML format at: http://www.turnstep.com/Faq/index.html Please do not use this in any form without prior contact. Send all comments and questions to: Greg Mullane (aerobics@turnstep.com) Enjoy! ---------------------------------------------------------------------- Sections: Disclaimer What is misc.fitness.aerobics? Aerobic Exercise What is aerobic exercise? Aerobic Training What factors affect aerobic training? How often should I train? How hard? For how long? Workout Intensity How do I determine my target heartrate? What are some other methods for determining my workout intensity? Spot Reduction I do lots of outer thigh (tummy, buns, etc..) - Will that part of my body slim down first? Fat Burning How do I know when I'm exercising hard enough to burn fat? Exercise Duration Is it better to break my exercise sessions, or exercise for a longer period? Weight How much should I weigh? What's the best way to determine bodyfat percentage? Muscle Training Should I train my muscles as well as do aerobic activity? Which is better for muscle training: weights or Exertube (Dynaband)? Warm up and cool down What is a warm up, and how important is it to aerobic activity? What is a cool down, and how important is it to aerobic activity? Heat after working out Should I use steam, a sauna, or a hot tub right after a workout? How to begin a workout program I never exercised before? How do I begin? Step Aerobics What is step aerobics? What are the proper stepping techniques? How high should my step be? How can I increase my intensity? How fast should the music be? Exercise gadgets How good is (insert your favorite exer-gadget from tv here)? Exercise Injuries, reactions, and environment What should I do for an acute injury? What should I do for a chronic injury? What are some common exercise injuries? What are some common exercise reactions? What are some common environment concerns? Exercise and eating How long should I wait after eating to exercise? What is best to eat before an aerobic workout? What is best to eat after an areobic workout? Best time to exercise What is the best time of day to exercise? Certification How can I get certified as an aerobics instructor? (in the United States) How can I get certified as an aerobics instructor? (in the United Kingdom) Contacts What are some aerobics-related phone numbers? ---------------------------------------------------------------------- Disclaimer The questions and answers in the aerobics FAQ represent our best effort to provide general information. They are not to be read as gospel. Individual people have different needs and abilities, and all exercise routines suggested should be adjusted to suit the specific situation. It is best to consult a doctor before beginning any lifestyle change involving exercise, particularly if you have been sedentary, are very overweight or overfat, or have or suspect any sort of medical condition which might be exacerbated by exercise. ---------------------------------------------------------------------- What is aerobic exercise? The word aerobic literally means "with oxygen" or "in the presence of oxygen." Aerobic exercise is any activity that uses large muscle groups, can be maintained continuously for a long period of time and is rhythmic in nature. Aerobic activity trains the heart, lungs and cardiovascular system to process and deliver oxygen more quickly and efficiently to every part of the body. As the heart muscle becomes stronger and more efficient, a larger amount of blood can be pumped with each stroke. Fewer strokes are then required to rapidly transport oxygen to all parts of the body. An aerobically fit individual can work longer, more vigorously and achieve a quicker recovery at the end of the aerobic session. ---------------------------------------------------------------------- What factors affect aerobic training? Frequency, duration and intensity. Frequency refers to how often you perform aerobic activity, duration refers to the time spent at each session, and intensity refers to the percentage of your maximum heartrate or heartate reserve at which you work. ---------------------------------------------------------------------- How often should I train? How hard? For how long? Most experts believe that 3-5 times per week for a duration of 20-60 minutes at 60-90% of age-specific maximal heartrate or 50-85% of VO2max (heart rate reserve). ---------------------------------------------------------------------- How do I determine my target heartrate? The general formula for the average person is 220-age times 60% and times 90% of HRmax. For example, a 30-year old would calculate his target zone using the above formula: 220-30=190. 190x.60=114 and 190x.90=171. This individual would try to keep his heartrate between 114 (low end) and 171 (high end) beats per minute. The Karvonen Formula calculates your heartrate reserve range. To calculate it, take your pulse for one minute on three successive mornings upon waking up. (We will be using the case of a 30-year old male whose resting pulse was 69,70 and 71 for an average of 70 over the 3 days.) Calculate target heartrate by subtracting your age from 220 (220-30=190). Subtract your average resting heart rate from target heartrate (190-70=120). The lower boundary of the percentage range is 50% of this plus your resting heart rate [(120 x .5) + 70 = 130]. The higher boundary is 85% plus your RHR [(120 x .85) + 70 =178]. Using the Karvonen Formula for percentage of heartrate reserve, this 30-year old man should be working between 130 and 178 BPM. Like the maximum heartrate formula, the Karvonen formula can vary from individual to individual. Not every individual is "average", and there can be large differences among people. Therefore heartrate alone may not be the best indicator of how hard or how well you are working. It is important to note that the deviation in both the age-specific formula and the Karvonen formula is due to the estimation of HRmax. If you have an actual HRmax from a graded exercise test, it will be more accurate. ACSM lists two formulas for estimating HRmax, each one with a standard deviation of +/- 10-12 BPM: HRmax = 220 - age (low estimate) HRmax = 210 - (0.5 * age) (high estimate) HR = exercise intensity * HRmax * 1.15 Source: ACSM's Guidelines for Exercise Testing and Prescription, 5th Edition, p. 274, Williams and Wilkins ---------------------------------------------------------------------- What are some other methods for judging my workout intensity? The Borg scale of perceived exertion is another way of determining how hard you are working. Using your own subjective Rate of Perceived Exertion (RPE) on a scale of 6-20 or a scale of O-10, you determine how hard you *feel* you are working. A rating of 12-16 ("somewhat hard" to "hard" on the 12-20 scale) or a rating of 4-6 ("somewhat strong" to "very strong") on the 0-10 scale reflects a heartrate of 60-90% of maximum and should be the target area for which to strive. Original Scale Revised Scale 6 0 Nothing at all 7 Very, very light 0.5 Very, very weak 8 1 Very weak 9 Very light 2 Weak 10 3 Moderate 11 Fairly light 4 Somewhat strong 12 5 Strong 13 Somewhat hard 6 14 7 Very strong 15 Hard 8 16 9 17 Very hard 10 Very, very strong 18 * Maximal 19 Very, very hard 20 Source: ACSM's Guidelines for Exercise Testing and Prescription, 5th Edition, p. 68, Williams and Wilkins The talk test is another measure of intensity. You should be able to talk without gasping for air while working at optimal intensity. If you cannot, you should scale down. On the other hand, if you can sing an aria from Madame Butterfly, then you need to work harder. ---------------------------------------------------------------------- I do lots of outer thigh (tummy, buns, etc.) work. Will that part of my body slim down first? No. When we're working a muscle or group of muscles to burn fat, we have no control over what part of the body we burn fat from. There is no such thing as "spot reducing". Fat generally is used up in pretty much the reverse order it was put on, (LIFO - Last In First Out). When you are exercising, the blood is carrying fat from all over the body to provide the energy. The muscles which are being worked will improve, of course, so when the layers of fat finally do get worked off, you'll have some nice lean tissue to show for all your efforts. Another aspect to this question is the fact that muscle growth underneath a fat deposit can give the appearance of spot reduction. This is because the overlying fat is stretched over a greater surface and appears thinner, although the total amount of fat is the same. A good analogy is with a balloon. As the air is increased, the skin on the balloon gets thinner, but the amount of balloon material stays the same. I think that this may be how the spot reduction myth originated. By working the muscles below the fat, people think they are actually making the fat go away. ---------------------------------------------------------------------- How do I know when I'm exercising hard enough to burn fat? Actually, you're almost always burning fat at one rate or another, but you burn most when your body is in its aerobic range. A good rule of thumb is that after 20 minutes in your aerobic zone, you will be burning more fat than carbos. Covert Bailey, in Smart Exercise, states that you will be burning fat after only twelve minutes of aerobic exercise. If you can increase your aerobic activity to 30 minutes or longer, you will be burning a larger percentage of calories from fat. There is still some disagreement as to which is better - longer duration at lower intensity, or shorter duration at higher intensity. If you are limited in time, then the higher intensity will maximize your aerobic benefits in a shorter amount of time. If you can work for a longer duration at a lower intensity, you will decrease your chance of injury. The object is to burn more calories than you take in. 3,500 calories equals l pound of fat. Your muscles will continue to burn fat after both aerobic and anaerobic (muscle training) exercise. This is perhaps the most common question raised by individuals exercising for the purpose of either weight loss or simply weight control. This stems from the recognition that aerobic exercise is a significant adjunct to any weight loss program, that is diet plus aerobic exercise produces more weight loss than diet alone. In addition, the weight lost with exercise tends to be a higher percentage of fat. Exercise can be grouped into three broad levels of intensity, mild, moderate, and high. Mild intensity is a comfortable walking pace and can be sustained almost indefinitely, moderate intensity is equal to an average cardiovascular conditioning workout (able to talk, but not sing) and can be sustained (in a trained individual) for upwards of 3 - 4 hours, and high intensity is not able to talk and can only be sustained for 30 - 45 minutes. Based on recent and very detailed research studies, in terms of absolute fat burning, a moderate intensity workout burns the most fat. At a heart rate equal to about 75% of max, fat burning will approach 0.5 grams - 1.0 grams of fat per minute. There is a weight dependence with the lower end referring to a 100 pound individual and the upper end to a 200 pound person. As the duration continues (greater than 1 hour), fat burning can increase slightly (another 10%). At a mild intensity, the majority of calories expended (85 - 90%) are fat calories, but the absolute level is only about 60% of the moderate intensity. At high intensity levels, fat burning declines to a level of about 65% of the moderate pace, as sugar burning supplies the rest. The high rate of sugar burning exhausts the limited sugar supply in muscles and causes muscular failure. The only caveats for the above burn rates are that these numbers are derived from individuals who were already aerobically trained and were conducted in the AM before breakfast. Less fit individuals are known to burn less fat and more sugar (part of aerobic conditioning is greater reliance on fat burning for energy). Exercising after a meal will tend to promote more sugar burning. Consumption of sugar during an exercise session will also tend to retard fat burning in favor of the sugar. These numbers were derived from cycling and so the absolute numbers can be increased if exercises that involve more muscle groups are utilized (running, rowing, etc.). From peak energy production rates for various exercises, rowers might reach about 40% higher. ---------------------------------------------------------------------- Is it better to break my exercise sessions up, or exercise for a longer period? There are TWO distinct thoughts on this issue: Both present fairly reasonable arguments. First, It takes 15-20 minutes to get your metabolism into the fat burning zone many people desire for an aerobic workout. Once you have reached this level, your body tends to obtain more of its energy from fat than carbohydrates. Using this argument, a single 90-minute workout will allow you to exercise in this "fat burning" zone for at least 70 minutes while two 45-minute sessions would allow you to be in this zone for at least 50 minutes (2 x 25). This logic supports a single, longer workout. Second, For 6 or so hours after a workout your body remains in "afterburn" mode, burning more calories at rest than it would have if you had not worked out. Using this logic, two sessions would produce two afterburn periods and result in more fat being burned than would be for a single workout session. The real bottom line is that if you exercise for 90 minutes a day, you're interested in more than just fitness(don't get me wrong, this is perfectly OK). To stay in reasonable cardiovascular shape, you need to perform aerobically for 20-30 minutes at least 3 times a week. If you wish to be in better than "the minimum acceptable" shape, remember that the returns are not geometric (you won't be in twice as good shape if you workout for twice as long). Therefore, if you're going to workout for 90 minutes a day, splitting the time between one or two sessions probably doesn't make a significant fitness-level difference. ---------------------------------------------------------------------- How much should I weigh? What you weigh is not as important as the percentage of bodyfat to lean tissue. You can be overweight without being overfat and vice versa. Since muscle weighs more per volume than fat, and you want to have firm muscles throughout your body, you may weigh more than you thought was average for your height and build. There is still much controversy over what is "ideal" bodyweight. While some body fat is essential to sustain life, it is generally thought that a healthy bodyfat percentage for males is 8-20% and for females is 13-25%. Source: ACE Instructor Manual, 1993, p.178 ---------------------------------------------------------------------- What's the best way to determine Body Fat Percentage? Weighing in water (hydrostatic) is generally considered the best method. But, the real answer is that a single measurement, no matter how accurate, doesn't tell you much. What's really important is, are you gaining or losing fat? The best way to answer this question is to take a reading every few weeks and graph the results. The absolute accuracy of these readings isn't really important as long as you use consistent technique so that the error is about the same every time. The two methods that work best for at-home measurements are skin-fold calipers and biceps IR units. Treat the numbers not as "body fat percentage" but as a "body fat index." If, after several readings, your body fat index is clearly trending up, you may want to reconsider your diet and exercise programs. It's like the gas gauge in your car - it doesn't tell you how many gallons you have, but it gives you a relative indication.