Spindoc Heartrate Monitor Training Guidebook

Transcription

1 Spindoc Heartrate Monitor Training Guidebook Edited by: Chandler Rhinehart THE PHYSIOLOGY (A SIMPLIFIED TAKE) Notes from Lactate Threshold Training by Len Kravitz, Ph.D. and Lance Dallack, Ph.D. Notes from Stephen Seiler s Dissertation, pub. 1996, revised 2005 Notes from Thoughts on Recovery by Vern Gambetta and his ongoing blog at Notes from The Lactic Acid Myths by Matt Fitzgerald Notes from The Heart Rate Monitor Guidebook To Heart Zones Training Sally Edwards Notes from Cycling Performance Tips by Mike Mitchell (online at Notes from Body Recomposition by Lyle McDonald About Your Heart... S. Seiler: The beating frequency (heart rate) is controlled by the balance of stimulation coming from the sympathetic (fight or flight) and parasympathetic (rest and recover) branches of the autonomic nervous system. The average untrained person has a resting heart rate of approx. 70 bpm as a result of some constant sympathetic stimulation. With training, the balance between parasympathetic and sympathetic stimulation tends to shift in favor of the parasympathetic, resulting in a lower resting heart rate. Elite endurance athletes may have a resting heart rate of 35 to 40. As we get older, maximum heart rate decreases. This is contrary to prior thinking and accepted wisdom. In addition, there is no strong evidence to suggest that training influences the decline in maximum heart rate. This reduction appears to be due to alterations in the cardiac electrical conduction system as well as down regulation of beta- 1 receptors. While research continues regarding the volume of blood ejected from the left ventricle in each beat (stroke) in aging athletes, it appears that if middle aged and older athletes continue to train 1

2 intensely, stroke volume is well maintained. Compliant vessel walls stretch when blood is pumped through them, lowering the resistance that the heart must overcome to eject its volume of blood each beat. As we age our arteries are not as compliant and flexible as they were. Consequently, resting blood pressure and blood pressure during exercise slowly increase as we age. Continued training appears to reduce this aging effect, but does not eliminate it. The major difference in the endurance-trained heart is a bigger stroke volume. The trained heart gets bigger and pumps more blood with each beat. So, that small reduction in maximal heart rate is more than compensated for by an increase in stroke volume. The distinction between the athlete s heart and the sedentary heart is the larger stroke volume of the trained heart. The heart can metabolize fat, lactate and blood glucose with equal effectiveness. The quantity of work that can be performed by the skeletal muscles over an extended period of time is critically dependent on the volume of blood that can be delivered by the heart. A body supplied more oxygen by a bigger pump has the potential to sustain work at a greater maximal density. Maximal cardiac output = maximal heart rate x stroke volume. Endurance training impacts myocardial function (1) at rest; (2) during sub-maximal exercise; and (3) during maximal exercise. While a lower resting rate is a typical feature of the endurance-trained hart, there is substantial variability in the resting heart rate and its response to training. Recent studies have demonstrated a substantial genetic variability in the responsiveness to training. So some people will respond more dramatically to the same training stimulus than others. When we begin to exercise at any given intensity, more oxygen must be delivered to the working muscle. If an individual starts training, after three months some changes will have already taken place. Cardiac output will be the same, but the heart will deliver more blood with each beat. Therefore, with continued training, heart rate at this any sub-maximal exercise intensity will be reduced. Remember max heart rate does not increase with training, but maximal stroke volume does increase. This is the primary reason for the increase in VO2 max. Another important change is an increase in blood volume, helping you take advantage of the increased filling capacity of the heart and increased stroke volume. S. Edwards: Fit women with the same body size have higher heart rates for the same work load as fit men. This is due to women s smaller left ventricle and lower blood volume, the result of males having more testosterone and its effects on all muscles of the body. S. Seiler: With regular exercise the body actually grows new blood vessels and increases the size of existing blood vessels. This increases efficiency of blood flow, which means increased 2

3 efficiency of oxygen transport to working muscles. The total number of capillaries per muscle in endurance-trained athletes is about 40% higher than in untrained persons. Maximal Oxygen Consumption VO2 Max S. Seiler: VO2 Max is defined as the maximum volume of oxygen that the body can consume during intense, whole-body exercise, while breathing air at sea level. VO2 Max is a quantitative measurement expressed in milliliters of oxygen consumed per kilogram of body weight, per minute (ml x kf-1 x min-1). Because oxygen consumption is linearly related to energy expenditure, when we measure oxygen consumption we are indirectly measuring an individual s maximal capacity to do work aerobically. (Image from Prof. Frank Katch) When you are exercising, your oxygen uptake increases as you increase your efforts. With each increase in speed or resistance, more muscle mass will be employed at a greater intensity. Oxygen consumption will increase linearly with increasing workload. However, at some point an increase in intensity will not result in an appropriate increase in oxygen consumption. The oxygen consumption will completely flatten out despite ever-increasing workload. This is the true indicator of achieving VO2 max. Every cell consumes oxygen in order to convert food energy to usable ATP for cellular work. It is muscle that has the greatest range in oxygen consumption. At rest, muscle uses little 3

4 energy. However, muscle cells that are contracting have high demands for ATP. So it follows that they will consume more oxygen during exercise. To receive this oxygen and use it to make ATP for muscle contraction, our muscle fibers are absolutely dependent on two things: (1) an external delivery system to bring oxygen from the atmosphere to the working muscle cells; and (2) mitochondria to carry out the process of aerobic energy transfer. Several experiments support the concept that, in trained individuals, it is oxygen delivery, not oxygen utilization that limits VO2 max. The capacity of skeletal muscle to use oxygen exceeds the heart s capacity for delivery. This limitation as analogous to turning on all the faucets in your house while trying to take a shower; the shower pressure will be inadequate because there is not enough driving pressure. So the bigger the pumping capacity of the heart, the more muscle can be perfused while maintaining all-important blood pressure. As further evidence of delivery limitation, long-term endurance training can result in a 300% increase in muscle oxidative capacity, but only about a 15-25% increase in VO2 max. Stroke volume, in contrast, is linearly related to VO2 max. Training results in an increase in stroke volume and therefore, an increase in maximal cardiac output. Greater capacity for oxygen delivery is the result. More muscle can be supplied with oxygen simultaneously while still maintaining blood pressure levels. There is a significant genetic component to most of the underlying physical qualities that limit what we can achieve with training. Olympic champions are born with unique genetic potential that is transformed into performance capacity with years of hard training. Recent studies focusing on the genetics of exercise adaptation have also demonstrated that not only is our starting point genetically determined, but our adaptability to training (how much we improve) is also quite variable and genetically influenced. What is Lactate? The Lactate Threshold L. Kravitz: Lactic acid and lactate are not the same thing, although they are often erroneously used interchangeably. Lactic acid is an acid; it is not produced in the body. The body does produce lactate, which is lactic acid minus one proton, and is the product of a side reaction in glycolysis. M. Fitzgerald: We now know that lactate is an intermediate link between anaerobic and aerobic muscle metabolism that serves as both a direct and indirect fuel for muscle contraction and delays fatigue in a couple of different ways. S. Seiler: Originally lactate buildup (increased acidity or acidosis) in muscles was blamed for muscle fatigue in endurance athletes. M. Fitzgerald: [Now scientists know] the muscles never reach a level of acidity that would directly cause dysfunction (or fatigue) of the muscle fibers. What s more, research conducted 4

5 within the past decade has shown that lactate counteracts another cause of muscle fatigue at high exercise intensities: namely, depolarization. It s a very lengthy and complicated bit of science (which includes sodium and potassium molecules trading places back and forth from inside and outside the muscles cells) to understand depolarization, but suffice to say there is a resulting buildup of potassium outside the muscle cells causing weaker and less efficient muscle contractions. M. Fitzgerald: It is now widely recognized by researchers in this area that muscle cell depolarization is a much more significant cause of muscle fatigue than muscular acidosis. Also, high levels of lactate partially restore muscle cell function in a depolarized state. Hence, if your muscles did not produce large amounts of lactate during high-intensity exercise, your muscles would actually fatigue a lot sooner. In a nutshell: According to the classical theory of lactate, one of the highest priorities of training was to reduce the amount of lactate the body produces at higher exercise intensities so that the athlete can race faster without fatiguing due to high lactate levels. According to the new theory of lactate, one of the highest priorities of training is to increase the body s capacity to use lactate during high- intensity exercise so that the athlete can race faster. M. Fitzgerald: In the new scientific understanding of lactate, arguably the most important role of lactate during exercise is not to delay fatigue caused by muscular acidosis or muscle cell depolarization [by acting as a buffer] but is rather to serve as a direct and indirect fuel for muscle contractions. The body has two fuel conversion systems. One utilizes oxygen as a necessary component, and is therefore dubbed aerobic metabolism. Burning fat is aerobic metabolism. The other energy system does not use oxygen, and is termed anaerobic metabolism. As the workload increases and VO2 max is reached and surpassed, more anaerobic metabolism is utilized for energy. Conversion of Carbohydrate to Fuel S. Seiler: Carbohydrates you consume are converted from the various sugar molecules into glucose, which is either used immediately or stored in the form of glycogen. During exercise, glycogen is broken back down into glucose which then goes through a sequence of enzymatic reactions. This happens fairy rapidly and yields some energy for muscle work in the process. Every single glucose molecule goes through this sequence to have useful energy extracted and converted to ATP (the energy molecule that fuels muscle contraction and all other cellular energy-dependent functions). Glucose has now been converted to a molecule called pyruvate, which can either be shuttled into the mitochondria (via an enzyme) or converted to lactate (via a different enzyme). If the pyruvate enters the mitochondria it is further broken down via enzymes and oxidation, and 5

6 yields ATP. It is the conditions in the muscle tissue that determine whether pyruvate yields ATP or becomes lactate. In a single contracting muscle fiber, the frequency and duration of contractions will determine ATP demand. ATP demand will be met by breaking down a combination of two energy sources, fatty acids and glucose molecules. As ATP demand continues to increase, the rate of glucose flux increases. If the muscle tissue is packed with mitochondria the pyruvate will tend to be converted into ATP, with relatively little lactate production. If and when lactate is produced from glucose breakdown, it will tend to be transported from the area of high concentration inside the muscle cell to lower concentration out of the muscle fiber, into extracellular fluid, and then into the capillaries. This is how the circulatory system removes the lactate from the muscle tissue. L. McDonald: When you start exercising, [before long] the body can t make ATP quickly enough and you get an increase in something called ADP, which is further metabolized to AMP. This shift in the ATP/AMP ratio is what turns on AMPk (a cellular energy sensor which reacts to changes in the energy state of the muscle cell). The cell senses that its energy levels have been disrupted so it turns on other stuff to try and combat that; AMPk activation is a big part of what happens. And when you activate AMPk along with doing a bunch of other stuff you get an adaptation. Mitochondria proliferate, aerobic enzymes increase; endurance improves. Conversion of Fat to Fuel S. Edwards: Fat is stored in fat cells as triglycerides, large molecules that cannot pass through the cell wall and into the bloodstream. When energy is needed, the fat cells are stimulated by enzymes to divide the fat molecules into smaller pieces (fatty acids), which are then released into the bloodstream and then into the muscle tissue. Once in the bloodstream in sufficient concentration, the fatty acids are drawn into the muscle tissue where more enzymes prepare them for the mitochondria to convert the chemical energy to ATP. Oxygen is a necessary part of the process. Once workload starts to tip the oxygen threshold and oxygen intake is reduced the body turns to burning more carbohydrate than fat. More lactate is released which begins to block the enzymes that break down the fat molecules leaving them trapped inside the cells. Fatty acid metabolism will account for a higher percentage of ATP need. Fat metabolism does not produce lactate. S. Edwards: Training teaches the metabolic process how to preferentially pick burning fat over sugar. The body increases the activity of the fat burning enzymes, more fatty acids are released, blood flow increases to move the fatty acids to the mitochondria, and the body increases the size and the number of mitochondria. Research has shown that mitochondria get about 35% bigger with exercise while there can be as much as a 15% increase in the 6

7 quantity of mitochondria. The mitochondrial enzymes activity is increased, upping the efficiency of the muscles to utilize oxygen. The body stores more fat reserves than carbohydrate reserves. You store a limited supply of carbs in the muscles, blood and liver in the form of glycogen. That is why the endurance athlete trains to expand the range of his aerobic workload; with a larger amount of fat cells to burn, he does not want to roll over into the anaerobic or carb-burning zone. He will use up his carb-based energy and bonk. In addition, the amount of carbs stored in the body is largely dependent on diet. A low-carb diet will provide less carb stores. Overview S. Seiler: The muscle at work: At a low workload, glycolytic flux is slow (fatty acid breakdown is relatively high at low intensities) and the pyruvate produced is primarily shuttled into the mitochondria for breakdown utilizing oxygen. Since the intensity is low, primarily slow twitch muscle fibers are at work; they have a high mitochondrial volume. As workload increases, ATP demand increases resulting in higher pyruvic acid production. A greater proportion of this production is converted to lactate rather than entering the mitochondria. Meanwhile, some fast twitch motor units are starting to be recruited. This will add to the lactate produced in and transported out of the working muscle due to the lower mitochondrial volume of the fast twitch fibers. The rate of lactate appearance in the blood stream increases. The body at work: The body is not just producing lactate, but also consuming it. The heart, liver, kidneys, and inactive muscles are all locations where lactate can be taken up from the blood and either converted back to pyruvic acid and metabolized in the mitochondria or used as a building block to resynthesize glucose in the liver. But when the rate of lactate production exceeds the rate of uptake, lactate accumulates in the blood volume: the traditional lactate threshold. Lactate itself is not the cause of the burn (acidosis) felt in muscles in a very hard effort. Instead, fast- twitch muscles have been recruited (which have relatively fewer mitochondria than slow twitch and therefore uptake fewer protons). It is the greater accumulation of the stray protons produced in the body that cause the burn. S. Seiler: Below is a diagram depicting the current thinking regarding lactate threshold: two thresholds, labeled LT1 and LT2. (see also Lactate Threshold Based Training, below). The left hand zone represents an exercise intensity range where lactate production is low and lactate removal easily matches production. The middle zone represents a range of intensity where we see a marked increase in blood lactate production, but lactate removal also increases so that a new stable blood lactate concentration is achieved. Finally, the right hand zone represents intensities where lactate production now exceeds the maximal rate of blood lactate removal. Exercise in this intensity range results in accumulation of lactate and fatigue, now thought to be caused by deporalization and to a lesser degree acidosis. 7

8 The bottom line is that exercise intensities about the LT2 point can only be sustained for a few minutes to perhaps one hour depending on how high the workload is above the intensity at which lactate production exceeds maximal rates of removal. It is important to know that the lactate threshold is highly specific to the exercise task. A cyclist who jumps on a rowing machine will quickly become fatigued. Rowing employs different muscles and neuromuscular patterns that he is not trained for. This is specifically important to understand when using heart rate as a guide in cross training or for the multi-event athlete. Summary: Training results in a decrease in lactate production at any given exercise intensity. The lactate thresholds are both responsive to training and influenced by genetics. Time Overview of Training Adaptations S. Seiler: The three elements of endurance performance: 1 Maximal oxygen consumption. This is an oxygen delivery issue. A high maximal capacity for blood delivery means higher oxygen delivery and the potential for more muscle to be active simultaneously during exercise. VO2 max is primarily limited by the maximum pumping capacity of the heart, and the specific arterial development to the active muscles. 2 Lactate threshold. This is an oxygen utilization issue. The greater the intensity of work we can achieve prior to the point when we begin to accumulate inhibiting acidity, the faster sustained pace we can tolerate. The limiting adaptations are the capillary density, fatty acid breakdown, enzyme level and mitochondrial density in the specific skeletal muscles used in your sport. Combining elements (1) and (2) gives us the sustainable power output of your performance engine. 3 Efficiency. This links sustainable power to performance velocity. The better the efficiency, the greater the achieved velocity at a given level of energy output. Since, ultimately, we have 8

9 a limited engine size, improvements in efficiency are critical to additional improvements in performance time. In a previously untrained person, VO2 max is increased significantly after only one week of training. [However,] after about 3-4 months of regular exercise, the improvement in maximal oxygen consumption begins to level off. After another 6 months of training, it will have increased little more, if any. As VO2 max builds, so does lactate threshold. After 6 months of training, lactate threshold can improve by as much as 25%. If you continue to train and increase intensity appropriately, lactate threshold will continue to improve slowly for a longer period, and not plateau for probably several years. It is important to remember that the lactate threshold is even more specific to the mode of exercise than the VO2 max. So if you are a runner and decide to add swimming and cycling to your training and compete in triathlons, you will immediately recognize that your running fitness does not immediately transfer to the bike, and of course not to the water. The third element of the endurance adaptations is efficiency. Efficiency is defined as mechanical work/metabolic work. We can divide efficiency factors in to two categories: internal and external. By internal, we mean the difference in muscle characteristics. Slow twitch fibers are more metabolically efficient than fast twitch. Athletes with a high percentage of slow twitch fibers tend to use less oxygen at a given power output than athletes with a higher percentage of fast twitch fibers. The external differences have to do with how effectively we transfer force to movement. In sports like swimming, rowing, and cross country skiing, there is massive potential for improvement. More effective force application, less wasted motion, and lower movement frequencies (with higher force per stroke ) are all characteristics of efficient technique. Elite cyclists sustain higher power outputs despite similar physiological values in part by learning to distribute the pedaling force over a larger muscle mass. In a nutshell, two of the three performance variables reach their peaks as you train. VO2 max peaks and plateaus after about 1 year of training; lactate threshold peaks and plateaus after 3-4 years of training. The only variable one can continue to improve is efficiency. Therefore, you must construct your training program with more and more care to continue making progress in those adaptations that have room to improve while maintaining the levels of those that have plateaued or are beginning to. This will often mean finding the right distribution of a limited amount of training time among a variety of workout types. 9

10 YOUR FITNESS PLAN M. Mitchell: Create your own plan based on your goals. Start at whatever fitness level you are on and consider your personal goals, whether simply gaining and maintaining basic fitness or training for an event. How much time can you train each week? Be realistic here because [being overzealous] can and probably will have a negative impact on achieving goals. S. Seiler: You will want to design a training program that will result in muscular development suited to the combination of strength and endurance that your sport requires. Are you planning on sprint-type sports events or endurance events? On average, we have about 50% slow and 50% fast twitch fibers in most locomotory muscles, with substantial intra-individual (and muscle-to-muscle) variations. The exact composition of each muscle is genetically determined. Gram for gram, the two types are not different in the amount of force they produce, only their rate of force production. There is no compelling evidence to show that human skeletal muscle switches fiber types from fast to slow due to training. So why do you try to develop fast and/or slow twitch? Slow twitch muscle has a higher density of mitochondria. With intense training, fast fiber types can develop more mitochondria and surrounding capillaries. So can the slow fibers. Training improves your existing fiber distribution s ability to cope with the exercise stress you create for it. In addition, fiber type alone is a poor predictor of performance. In fact, there is evidence to suggest that a mixed fiber composition is ideal for success in an event like the mile run, or if good performances are to be possible in a range of sporting events. For the pure endurance athlete, more slow-twitch fibers are advantageous. These fibers give up lightening contraction and relaxation velocity for fatigue resistance. Lots of mitochondria and more capillaries surrounding each fiber make them more adept at using oxygen to generate ATP without lactate accumulation and fuel repeated contractions. After finishing a workout, you are actually physically weaker, not stronger. The cells always seek to maintain homeostasis, or the status quo, so the cellular and systemic stress of exercise elicits not just a repair to former levels, but an adjustment, or build-up, of the stressed system that serves to minimize the future impact of the stressor. If the stress is too small in either intensity or duration, little or no adaptation growth is stimulated. On the other hand, if the stress is too severe, growth is delayed or even prevented. The optimal training program would be one that maximally stimulated these positive adaptations, while minimizing the cellular and systemic stress thrown at the body in order to trigger the changes. Finally, your overall training program would have to recognize that some cellular adaptations have a faster response time than others. What we are faced with as we continue training is a diminishing return on our training investment. The better adapted we are to exercise the more difficult it is to induce further positive changes. Emerging from this fact is the use of periodization in training. 10

11 For more on periodization, see SpinDoc s Periodized Training document, available on our website at Thoughts on Cross- Training S. Seiler: Your chosen sport requires a very specific pattern of joint and muscle coordination and will place high metabolic demands on a very specific group of muscles. A high endurance capacity in a specific sport requires both (1) high oxygen delivery (cardiac output) and (2) high local blood flow and mitochondrial density in the precise muscles used. The only way to optimally develop the second component of endurance is to train those exact muscles by doing your sport. Does that mean you should not cross-train? You definitely should. But you need to understand what the limited purpose and value of the alternate exercise modes are (unless you are a multi-sport athlete). Seiler trains skaters. He added cycling to maintain their training volume, using the cycling hours as their low intensity and recovery workouts. For himself, a rower, he cross-trains by running or cycling. A little bit of cross-training helps maintain a general aerobic base while allowing you to mentally and physically recharge for your chosen sport. Another reason to cross-train is to avoid injury and maintain muscular balance during a period of intense sport-specific training not just in the off-season. Cross-training should always be limited to those activities that allow you to do your event-specific training workouts with greater enthusiasm and intensity and/or less risk of injury. Both exercise level and creative mental activity as potential modulators of health and performance should be part of your training program. When you build a training program, you have to consider the brain as well as the body. Seiler had a great story about a marginal soccer team making it all the way to the playoffs. Their coach discovered, while registering unimpressive performances, they spent their recovery time sitting in front of the TV. He started taking them to museums, got them to start learning foreign languages, and even started them on hand- crafts. Their sports performance skyrocketed. While this doesn t prove the brain/body sports connection, it indicates there is one. Your resting metabolic rate is increased as muscle mass increases: the more muscle mass you have, the more calories you burn just sitting still. Based on volume, muscle weighs more than fat. Components of a Training Plan M. Mitchell: Athletes usually modify their training program for one of two reasons: they want to go further or they want to go faster. If you are training for distance with the goal of going further and your current speed is fine, you will simply concentrate on slowly adding distance 11

12 (10% of your current distance per week). If you want to go at a faster average speed or increase your top speed, you will need to increase your lactate threshold. This means incorporating maximal steady-state and interval training to your weekly workouts. If you want to improve both speed and time, you will need a combination of intervals, max steadystate, and longer distances in your weekly workouts. A good training program will be designed to include both aerobic and anaerobic workouts. It is the art of finding the balance of types of exercise (aerobic vs. anaerobic; interval training; steady- state training; and fartlek training) in your overall program, which will determine its effectiveness for the competitive event for which you are training, or simply for maintaining high fitness. If you are beginning a training season, LSD (long- slow- distance) training is important while developing a base and in preparation for very long endurance events. (For more, see SpinDoc s Periodized Training document.) M. Mitchell: A suggested outline for a weekly program might look like: 3 days of high level cardiovascular work, 1-2 of which are intervals 1 day training at the duration and close to intensity of the upcoming event 1 day of LSD work 2 days of recovery, or one can be a short, easy loosen up effort This suggested workout assumes you have developed an aerobic based beforehand. S. Seiler: Cardiac performance is a primary determinant of the VO2 max, and interval training enhances maximal cardiac performance, and therefore, presumably, VO2 max. Intermittent high intensity training (interval training) results in enhanced maximal cardiac performance; it is also a powerful stimulus for increasing blood volume, which is a critical adaptation that contributes significantly to improved maximal cardiac output and VO2 max. However, your training plan should not be predominantly interval workouts. While intervals are effective at producing the adaptations that improve VO2 max, these adaptations will plateau. Therefore, the site of adaptation needs to move from the cardiovascular system to the skeletal muscles. The most powerful stimulus for change in skeletal muscle aerobic capacity is different from the most powerful stimulus for cardiac functions changes. Instead, you must put in the hours of continuous constant intensity exercise to maximize these adaptations. This will range from steady state efforts at 65-75% of VO2 max lasting 45 to 120 minutes to repeated anaerobic threshold work at 80-90% of VO2 max for 15 to 30 minutes. L Kravitz: Traditionally, VO2 max has been viewed as the key component to success in prolonged exercise activities. However, more recently scientists have reported that the lactate threshold is the most consistent predictor of performance in endurance events. At rest and under steady-state exercise conditions, there is a balance between blood lactate production and blood lactate removal; the lactate threshold refers to the intensity of exercise at which there is an abrupt increase in blood lactate levels. 12

13 Although the optimal training for lactate threshold improvement has yet to be fully identified by researchers, there are still some excellent guidelines you can follow in generating training programs and workouts in order to optimize endurance performance. Research has indicated that training programs that are a combination of high volume, maximal steadystate [also LSD, or long-slow-distance], and interval workouts have the most pronounced effect on lactate threshold improvement. S. Seiler: On busy days when you only have 30 minutes to train, a brief warm-up and one hard 20-minute steady state workout is more beneficial than resorting to a series of very short intervals. Short, very high intensity interval training has only a small niche in the endurance athlete s training program. It has limited value in building the performance engine. The focus must be on longer bouts of exercise as the foundation of the training program. It is the consistency and volume of exercise at 70-90% of VO2 max in your training program that is going to have the single biggest long-term impact on your progress. Last, good athletes develop breathing rhythms that tune in to the rhythms of their movements. This probably promotes efficiency. When you feel yourself performing at your physiological redline, your breathing may be a place to turn your attention. If you are a runner or cyclist, focus on the diaghram and the abdominal muscles for moving the air in and out, instead of the intercostals attached to the chest. Heaving the chest more than necessary costs extra energy. Belly breathing makes sense. Tie your breathing in with your pace and focus on its efficiency. Rest and Recovery M. Mitchell: Sometimes your body won t follow your prescribed workout schedule. It is important to listen to it. This is a good guideline for determining if you need an extra day off. When you are working out, determine if any of these combinations exist: 1. Heart rate is higher than normal and legs feel tired 2. Heart rate is normal and legs feel tired 3. Heart rate is higher than normal and legs feel good 4. Heart rate is normal and legs feel good In the first situation, your recovery isn t close to what it should be; take the day off. In the second and third scenarios, recovery is incomplete but keep the workout light and short. In the fourth case, you are right on schedule have at it! One must schedule and adhere to rest as an essential part of the training program. Rest is the most important part of training. Rest means different things to different people. For most it is either no riding or very little activity. For others it may consist of minutes of exercise at very low heart rate. 13

14 V. Gambetta: Recovery is a key factor in performance. It is during the recovery that adaptation to training occurs. Recovery is the process over time needed to repair damage to the body caused by either training or competition. [Often] it is not thought of as part of the training process. To insure the highest quality training and to prevent overtraining, recovery must be planned as part of the training process. The key to all of this is the necessity to assess the athlete s recoverability, which is how well they are able to recover from the different workloads. Do this both subjectively and objectively. No two athletes recover and adapt from the same workout the same way. The means of assessment of recoverability is to closely monitor training and the response to training. Restoration is an active process; it is the means used to bring the athlete back to baseline. This is an actual planned training unit to help the body recover from training and to return to previous performance levels through removal of mental and physical fatigue due to training and competition efforts. Rest is time off with no training at all. For the athlete this is a poor alternative. The body is accustomed to a certain level of activity. When that is taken away it is a shock to the body. It interferes with appetite, sleep and general mood state. Complete rest makes the return to training more difficult. Rather than restoring the body the athlete coming off a day or longer of complete rest is flat. A much more viable alternative is active rest wherein muscles work, nerves rest. It is time off from the regular activities of training. Active refers to other sports activities. For example a swimmer may go for a bike ride, [a cyclist may go for a walk.] The global objectives of recovery/regeneration and the general strategies to address them are: 1. Restore glycogen levels. In order to be effective, carbohydrate should be taken within a 2 hour window after exercise. The guidelines for replenishment are 1 grams carbohydrate per kilogram of body weight for the first 2 hours post-exercise, and 1.2 grams per kilogram of body weight per hour in minute intervals for up to 4 hours post exercise. 2. Minimize the breakdown of muscle. This is a cumulative process; it is seldom that one workout will cause this. In order to recover the body must repair this damaged tissue by shifting to an anabolic state. Follow the protocal for carbohydrate but use 1:4 protein to carb. Research has shown that six grams of protein will accelerate protein synthesis after exercise. 3. Restore depleted electrolytes. This is an ongoing process throughout and after the workout. Replace essential electrolytes such as sodium, magnesium, potassium, chloride and calcium. 4. Hydrate and rehydrate. 14

15 5. Reduce inflammation. The stress of training produces micro tears and swelling in muscle tissue. There must be balance between allowing the body s natural inflammatory response to take place and minimize swelling that could inhibit training. 6. Reduce muscle soreness. A systematic cooldown that stimulates blood flow to the targeted muscles, gentle rhythmic exercise and static stretching help reduce onset of soreness. Gentle exercise in a swimming pool is very effective. 7. Boost the immune system. Systematic high level training will severely stress the body s immune system. This must be addressed by moderating lifestyle and through proper nutrition. 8. Proper sleep. 9. Proper recovery time between training sessions. Your Training and Recovery Management Log V. Gambetta: The key to management of the recovery process is a sound system of monitoring training to accurately assess the stress of training. The simplest [means] is just recording the results of the workout. In training there is an immediate residual and cumulative training effect; the ultimate goal of training is the long-term adaptation or the cumulative training effect. Monitor each of these effects in order to assess the program of training. Monitoring training will allow control of the training process and ensure a proactive adaptive response. Monitoring does not always provide immediate feedback; it takes times for patterns to emerge, so be patient. Planning the training and implementing the training are only two parts of the three-pronged attack. Monitoring the training is the third. The simplest and most effective means of monitoring training is a detailed training log. The log represents the athlete s personal training monitoring tool. The log should monitor factors outside of training: sleep, diet and other stressors that all can have an effect on training. This information is: Day/Date Hours of sleep Time of training Weather Duration of the session Energy rating Before workout The actual exercises Sets, Reps, Times Interval 15

16 Intensity Training demand rating scale (post training) Evaluation of planned work vs. work completed Rate your response to the work Breakdown of the time duration of each training component The training demand rating scale is a valuable tool that can be easily adapted to preferences. It can be used to rate training demand on individual components of the workout or the workout as a whole. For simplicity, use a 10-point scale. Training Demand Rating Scale 1 = Easy; no effort required 2 = Extremely light 3 = Very light 4 = Moderately light 5 = Light 6 = A little hard 7 = hard 8 = Very hard 9 = Extremely hard 10 = Maximal effort Rate and record the effort at the conclusion of the workout. Develop your own verbal descriptors for the various points on the scale. The personalization will make the information that much more meaningful. HEART RATE MONITORS AND THEIR USE CAVEAT: A heart rate monitor is a very useful measure of your current fitness level and an excellent training tool. However, it is just one of many tools available to you as you explore fitness, and should not be the final word in anyone s training. Factors such as drift, interference from other monitors, programming mishaps, and the delay between your actual heart rate and the rate appearing on your monitor, among other factors - - all can skew your heart rate monitor numbers, leading you to misconceptions about your workout or fitness level. Heart rate can vary also due to hydration status, environmental conditions and other physical factors. On the flip side of this coin, training based solely on Rate of Perceived Exertion doesn t work for everyone. Some athletes will push themselves way too far without a heart rate monitor to keep them in line. Others are uncomfortable pushing themselves, and will think they are working much harder than they are. Perhaps the best suggestion is compromise. Use a heart rate monitor in addition to perceived exertion, a well- balanced diet, a well- balanced multiple- disciplinary training program, and adequate rest, and you will maximize your benefits from this tool. 16

17 PROS and CONS OF USING A HEART RATE MONITOR M. Mitchell: The PROS: - as a motivational tool, like having a coach; it brings objectivity to a training program - to teach beginners to read their bodies and avoid anaerobic overtaining - to aid in doling out energy during a heavy effort, saving some energy for the end - to analyze race efforts and design a personalized training program - to indicate overtraining The CONS: - the lack of scientific support there is no evidence training with a monitor improves competitive performance - temperature and humidity greatly influence heart rate. When working out at high heat, blood flow is diverted to the skin to enhance heat dissipation disbursing the blood flow while cardiac output remains the same. In addition, it is theorized that sweating itself and the resulting decrease in body fluid causes the heart rate to rise as again there is less cardiac output. - too much data with little agreement on how to use the information to the best training advantage - the lag time in heart rate response and change in exertion - incompatibility with group training - riding on the road, it can distract from hazardous road conditions - its inconsistency at the same heart rate you re not always putting out the same effort day to day - the nature of heart rate monitors to drift (see glossary) Max Heart Rate vs. Lactate Threshold Edwards first training program was based on setting zones as calculated on max heart rate. However, many athletes now use other anchor points/physiological points to train by, such as lactate threshold. Edwards lists four biomarkers upon which a training plan can be based: Lactate threshold: lactate concentrations in millimoles of blood lactate. Lactate is one of the products of anaerobic carbohydrate metabolism in the cells; Ventilatory threshold: ventilatory changes with changes in the ratio of oxygen to carbon dioxide to total inspired and expired air; VO2 max: The maximum volume of oxygen that the body can consume during intense, whole- body exercise, while breathing air at sea level; and Max heart rate: Maximum heart rate is the fastest rate your heart can beat at highest intensity exercise, and increasing the workload does not increase the heart rate. 17

18 L. Kravitz: Traditionally, VO2 max has been viewed as the key component to success in prolonged exercise activities. However, more recently scientists have reported that the lactate threshold is the most consistent predictor of performance in endurance events. Heart Rate Monitors vs. Perceived Exertion M. Mitchell: In addition, there are ongoing debates between the value of heart rate monitor training v. perceived exertion as your training guide. How hard are you working? Are you getting the most from your training efforts? Heart rate monitors were touted as the only accurate measure, but perceived exertion is increasingly found to be an accurate measure. Allen Lim, Ph.D. analyzed data from power meters used by pro riders in races and training. Based on his research, he recommends a middle ground: training by feel and then analyzing the results by scientific means. I am going to write about Perceived Exertion Rate based training first; then Max Heart Rate based training, then about Lactate Threshold Training as an alternative approach to Max Heart Rate. PERCEIVED EXERTION TRAINING M. Mitchell: For some, perceived exertion (known in the industry as Rate of Perceived Exertion, or RPE) is the best way to train. According to Mitchell, there is no question that I feel different in training from day to day what I ate, time of day, an extra cup of coffee, and even the effects of my ride the day before. I worked through this quandary for myself a number of years ago and decided that perceived exertion, not using [heart rate] numbers avoided the focus on the monitor and in my mind made the most sense to maximize my training benefits and keep cycling enjoyable. The key to improving when using perceived exertion is to work at an effort you can barely sustain. Push beyond this and you ll accumulate too much fatigue and slow down. Go easier and you won t be riding at your best for your current fitness level. This maximum sustainable rate is around your lactate threshold; you can use a heart rate monitor to pinpoint the highest heart rate you can maintain for minutes, but if you listen to your body you can constantly monitor your sense of perceived exertion. Pay attention to your lungs and your legs. Your lungs: when your breathing is steady and regular, it means you re at or below your lactate threshold. Start to pant, and you ve gone over it. Back it off just a little. Your legs: if your quads are just uncomfortable, you are fine. If they start to burn, you have crossed the threshold and need to back off. 18

19 RPE Scale The RPE scale ranges from 6 to 20 and includes a literal description for each level of exercise intensity. It was designed so that adding a 0 to the level of exertion would give a rough estimate of your heart rate. For example at a resting rate (a 6 on the RPE scale), adding a 0 would estimate your heart rate at 60. Research has demonstrated an amazingly high correlation for any individual from day to day. Familiarize yourself with the levels. Then, when exercising, rate your level of exertion before checking your heart rate monitor or manually taking your pulse. With a little practice you will find that you can be pretty accurate in predicting your heart rate. Then you can use your own RPE instead of a heart rate monitor to determine your exertion rate. RPE Scale 6 Resting 7 Very, very light load 9 Very light load 11 Fairly light 13 Somewhat hard 15 Hard 17 Very hard 19 Very, very hard 20 Maximum effort RPE will change as fitness improves and with factors such as hydration, fatigue, carbohydrate status and ambient temperature. If athletes are in tune with themselves and quite experienced at perceiving effort, then what they perceive as hard can be used consistently as a reference point for training-induced adaptations and for determining training pace. MAX HEART RATE BASED TRAINING S. Edwards: Working in multiple zones brings multiple benefits. One of the wonders of the human body is its uncanny ability to adapt to whatever stresses we throw at it. This is, of course, a two-edged sword. If we expose the muscular system to resistance training, it adapts into this stronger model. This is why we believe strongly in cross-training, including cycling within different zones, to mix it up for the body and enable adaptation in different disciplines. Within each training zone, different physiological activities different stimuli to the body occur. These physiological and psycho-biological benefits including the metabolizing of different fuels (i.e. burning fat and carbohydrates), strengthening sport specific muscles, cardiovascularly conditioning different oxygen delivery systems, and training kinesthetic pacing skills. Using a heart rate monitor enables you to measure and monitor progress in a definitive manner. You can do this training without a monitor using perceived exertion rates (RPE) but it is obviously more subjective and less accurate. There is a slight delay as data is 19

20 relayed from the heart to the strap and then to the watch. In timed interval and other workouts, remember not to judge your effort by the initial figures displayed on the watch. Sally Edwards Training Zone Chart This chart is based on your estimated maximum heart rate. Zone Number Zone Name % of Max HR Benefit Z1 Healthy Heart Zone 50-60% Getting Fit Z2 Temperate Zone 60-70% Staying Fit Z3 Aerobic Zone 70-80%^ Getting Fitter Z4 Threshold Zone 84-90% Getting More Fit Z5 Red Line (Anaerobic) Zone % Fittest ^ I have added this modification to Sally Edwards chart. From roughly 80-84% is referred as the No Zone or no man s land. This is NOT a good place to train. It is too fast to be beneficial as aerobic base building, but is not hard enough to push the body into the strength adaptations that a heavy workload causes. The result is not a productive work effort and possibly leads to overtraining. (T. Shere; M. Mitchell) For suggestions on max heart rate self- tests, see the section at the end of this document entitled Self Tests. Max HR Formulas Debunked S. Edwards: There is no formula accurate enough to calculate your maximum heart rate. Period. According to Carl Foster, Ph.D., The formula like 220 minus age is useless. There is no scientific validation for it it was fabricated. Maximum heart rate is the fastest rate your heart can beat at highest intensity exercise, and increasing the work load does not increase the heart rate. Most researchers believe this genetically determined point is your body s way of protecting itself. Max HR cannot be increased by training. Max HR is affected by drugs. A higher or lower max HR does not predict a better athlete. Max HR varies among people of the same age as it is genetically determined. Children s Max HRs can be over 200, and don t settle into their final number until fully grown. Max HR does not vary from day to day. The peak heart rate you can achieve will vary depending on the form of activity. For example, say my max HR is 194. My peak heart rate running is 194; for cycling it s 183; and for swimming it s 170 bpm (beats per minute). Remember this is not max heart rate, which is always the same, genetically determined number. You have different peak heart rates that are specific per exercise mode due to the fact that some are fully weight bearing (running), some are partially weight bearing (cycling), and some use more large muscle mass than others. Body position differs between an indoor spin bike and your road bike, so even in this instance your peak heart rate will be different due to body position (probably more forward over the handlebars than on a spin bike). Peak heart rates should 20