Why Measure Heart Rate? - Polar Education Zone: Basic Heart Rate
Transcription
Why Measure Heart Rate? - Polar Education Zone: Basic Heart Rate
Welcome to the Polar Education Zone: Basic Heart Rate Training On completion of this course you will have knowledge in the following areas: Knowledge of how and why to use a Polar heart rate monitor. Knowledge of the benefits of heart rate training. Basic knowledge of the heart muscle and how it effects training. Basic knowledge of the energy pathways, fuel sources and metabolism. Knowledge of heart rate training basics (resting heart rate, average heart rate and maximum heart rate). Knowledge of how to determine a maximum heart rate. Knowledge of target heart rate zones for training. Knowledge of the factors that affect heart rate. Knowledge of the principles behind the super compensation curve. Knowledge of overtraining and how to avoid it. Knowledge of different types of training methods. Knowledge of planning sessions for different population groups using heart rate target zones. Knowledge of ways to monitor improvement. For successful completion of this course you must get 80% of the quiz questions correct. You will have only 2 attempts to get each question answered correctly. Therefore please ensure all of the course material in each section is read thoroughly before commencing the quiz. You have up to 3 months to complete the course including all online quiz questions and the feedback form. Once you have successfully completed the course your Certificate of Completion will be immediately available for download.. If you logout midway through the course, you can resume the course at anytime by logging back in. You will be taken to the last completed page. If you have any questions or problems please email education@polartrainingzone.com.au. First Australian Rights Pursuit Performance © 2014 1 Who is Polar? Polar has been leading the way in technological innovations and heart rate monitors since 1977 through expertise in sports, physiology and electronics, coupled with a deep understanding of customer needs. Polar offers a comprehensive product range, along with essential support for all levels of activity and fitness such as improving an athlete's sports performance, helping people enjoy a healthier lifestyle, aiding rehabilitation and assisting in weight management. First Australian Rights Pursuit Performance © 2014 2 Anatomy and Physiology: Understanding the Heart To begin to understand the principles and benefits of heart rate training, we need to first understand the working of the heart as a muscle in the body, and the role that it plays during exercise. The heart is a key component of the body's cardiovascular system. This system is designed to transport oxygen and nutrients to the cells of the body and remove carbon dioxide and metabolic waste products from the body. The cardiovascular system has three components: The heart (cardiac muscle) The blood vessels The blood The heart is the hardest working muscle in the human body. The adult heart is about the size of a closed fist and sits in the thorax on the left side of the chest in front of the lungs. It is responsible for pumping the blood and delivering oxygen throughout the entire body. The heart is surrounded by a double-layered membrane called the pericardium. The outer layer of this sac like membrane surrounds the roots of the heart's major blood vessels and is attached by ligaments to the spinal column, diaphragm, and other parts of the body. The inner layer of the membrane is attached to the heart itself. A coating of fluid separates the two layers of membrane, which allows the heart to move with each beat. The heart is made up of 4 chambers. The upper chambers are called the left and right atria, and the lower chambers are called the left and right ventricles. The left ventricle is the largest and strongest chamber in the heart. The walls are about a half-inch thick and have enough force to push blood through the aortic valve and into the body. The Heart Beat A heartbeat is made up of a two-part pumping action. The first part of this process is called diastole. As blood collects in the left and right atria, the sinus (SA) node sends out an electrical signal that causes the atria to contract. This contraction pushes blood through the valves into the right and left ventricles. The second part of the phase is called systole and begins when the ventricles are full of blood. The electrical signals from the sinus node (SA) travels along a pathway of cells to the ventricles, causing them to contract. As the tricuspid and mitral valves shut tight to prevent a back flow of blood, the pulmonary and aortic valves are pushed open. Blood is then pushed from the right ventricle and into the lungs where it collects oxygen. This oxygen-rich blood then flows from the left ventricle to the heart and other parts of the body. Once the blood has moved into the pulmonary artery and the aorta, the ventricles will relax, and the pulmonary and aortic valves will close. As the pressure lowers in the ventricles, the tricuspid and mitral valves open, and the cycle is then repeated. This series of contractions is repeated over and over again. Each electrical impulse leads to one heartbeat and the heart rate is determined by the number of electrical impulses. Therefore during times of exertion, more electrical signals will be produced, in turn increasing the number of times the heart contracts. The average heart normally beats about 60 to 80 times a minute when you are at rest. However, this can vary with age and level of fitness. Figure 1. The heart and blood circulation. First Australian Rights Pursuit Performance © 2014 3 Cardiovascular Fitness Cardiovascular fitness is the ability of the heart and lungs to supply oxygen-rich blood to the working muscles and the capacity of the muscles to use this oxygen to produce energy for movement. The body's ability to deliver oxygen to the working muscles is affected by many physiological parameters including: Heart Rate: The rate at which the heart beats. Stroke volume: The amount of blood the heart can pump out in one beat. Cardiac output: The amount of blood that is pumped out of the heart from one ventricle in one minute. VO2Max: The maximum capacity of an individual's body to transport and utilise oxygen during incremental exercise, which reflects the physical fitness of the individual. Most of us are aware of the importance of regular cardiovascular exercise and its affect on the heart, lungs and vascular system. Cardiovascular exercise not only allows us to carry out activities more efficiently but it also reduces the risk of many diseases and illnesses, including coronary heart disease, heart attack, cancer, diabetes, stroke and problems associated with ageing. The following slide demonstrates the differences in two clients of varying fitness levels. As you slide the hearts up the scale you will notice the varying speeds of both clients. The client with a higher cardiovascular fitness level will be able to maintain their speed at a desired heart rate for a longer period of time, compared to the unfit person who will become fatigued at a much earlier time during the session. As a client becomes fitter they will be able to run at a greater speed whilst maintaining the same or similar heart rate. For example, a person running a distance of 5 km at 145 bpm, who has increased their fitness by following a well designed exercise program, will be able to increase their speed and cover a distance of 5.5 km whilst still maintaining a heart rate of 145 bpm in the same duration of time. This is due to the heart becoming more efficient at distributing oxygen through the body and to the working muscles. Benefits of Cardiovascular Fitness Undertaking regular cardiovascular fitness can help to: Lower blood pressure. Increase HDL cholesterol (commonly known as 'good' cholesterol). Decrease total cholesterol. Decrease body fat due to utilising fat as energy. Increase heart function and its ability to pump more blood. Decrease stress reactions and anxiety. First Australian Rights Pursuit Performance © 2014 4 Reduce glucose-stimulated insulin. Increase oxygen output to body. Decrease resting heart rate. Increase cardiac output. Increase aerobic work capacity. First Australian Rights Pursuit Performance © 2014 5 Why Measure Heart Rate? Now that we know the importance of Cardiovascular fitness and understand how the heart functions, lets look at the most efficient way to utilise this information during a training program. Like any muscle in the body, the heart needs to be exercised regularly. The condition of the heart varies between people, largely due to influences such as: Intensity of physical activity. Emotions and stress. Onset of an illness. Exposure to heat and altitude. Consumption of stimulants such as coffee or alcohol. Heart rate monitoring is an important component of cardiovascular fitness assessment and it can become a tool for any training program as it is an accurate indicator of the body's physiological adaptation to the intensity of effort. Monitoring your client's heart rate is the safest and easiest way to keep them training at the right intensity; reducing their chance of injury or over training, and ensuring they get the results they desire. Using a Polar heart rate monitor will provide you (and your client) with an accurate gauge of the intensity of their exercise. By constantly monitoring their heart rate you can ensure they are training in a manner that is specific to their particular goal. You will learn to identify when their workouts are effective, when they are over or under training, and even when they may be getting sick or need recovery. 4 Main Reasons to Measure Heart Rate Exercise Safety Provides awareness of what heart rate limits are right for your clients. Prevents beginners from starting out too hard. Provides an early warning of overtraining and illness. Enjoyment Effective exercise does not need to be hard! Using personalised heart rate limits makes the workout more enjoyable. Calorie Burning Provides motivation by knowing how many calories have been burnt during a session. Maximises 'fat burning' training sessions. Assists in reaching weight loss / fat loss goals. Fitness Improvement and Effectiveness Monitors progression and improvement, providing motivation. Enables training at appropriate intensities based on fitness goals. Enables tracking and accurate adjustments to training programs. Exercising at the right intensity will utilise workout time more effectively. Provides awareness of the body's reaction to exercise. Provides immediate feedback, enabling exercise programs to be fine tuned for the best results. Provides the ability to control work and rest ratios during interval training. Helps maintain pacing strategy during competition. First Australian Rights Pursuit Performance © 2014 6 How is Heart Rate Measured? An electrocardiogram (ECG) is a medical test that detects cardiac abnormalities by measuring the electrical activity generated by the heart as it contracts. The machine that records the patient's ECG is called an electrocardiograph. ECGs from normal, healthy hearts have a characteristic shape. Any irregularity in the heart rhythm or damage to the heart muscle due to disease can change the electrical activity of the heart and the shape of the ECG. The ECG records the electrical activity that results when the heart muscle cells in the atria and ventricles contract. This information is demonstrated as a series of graph-like tracings, or waves. Figure 2. Normal Resting ECG, heart rate 60 bpm A typical ECG tracing of a normal heartbeat consists of a P wave, a QRS complex and a T wave. The P wave is the contraction of the right and left atria. Contractions of both the right and left ventricles show as a series of 3 waves, Q-R-S, known as the QRS complex. The third wave in an ECG is the T wave. This reflects the electrical activity produced when the ventricles are recharging for the next contraction. As the exercise intensity increases the time between the peaks ( R ) decreases therefore resulting in an increase in heart rate. Figure 3. Normal Exercising ECG, heart rate 170 bpm The electrical activity produced by the heart is what ECG and Polar heart rate monitors measure. This technology produces heart rate measurements that are continuous and extremely accurate. First Australian Rights Pursuit Performance © 2014 7 Heart Rate Training Basics It is a common misconception for people to confuse heart rate with pulse. It is important as a fitness professional to know the differences between these two terms. Pulse is the rhythmic contraction and expansion of an artery due to the surge of blood from the beat of the heart. It is usually measured to obtain a quick evaluation of a person's health. The pulse can be felt in any place that allows for an artery to be compressed against a bone, such as at the neck (cartoid artery) or the wrist (radial artery) Pulse can be measured manually during or immediately after exercise. This count can be done for 6, 10 or 15 seconds and then converted into beats per minute by multiplying the total by the number 10, 6, or 4 respectively. For Example: 6 second pulse count of 15 beats x 10 = 150 bpm. 10 second pulse count of 30 beats x 6 = 180 bpm. 15 second pulse count of 30 beats x 4 = 120 bpm. Unfortunately there are many problems associated with this method, such as the longer the count (i.e. 15 seconds), the less accurate the total will be as the heart rate will decrease quite rapidly once the individual has stopped exercising. Also, when converting short counting periods (i.e. 6 seconds) to beats per minute at such a high rate, any small unavoidable discrepancies will be magnified. It is important not to confuse pulse meters with heart rate monitors, as they are very different tools. Heart rate monitors measure and record the electrical impulses produced from the heart through the use of a chest transmitter, which provides an extremely simple and accurate way of measuring heart rate. Pulse meters rely on light waves passing through the blood vessels for heart rate detection, such as in the finger tip or earlobe. Pulse meters will generally only produce an accurate measurement when used indoors and seated or at rest. Polar heart rate monitors allow continuous and accurate measurements to be taken throughout all types of activity when manual pulse measurements would be difficult or even impossible to take. A Polar Chest Transmitter What is Average Heart Rate? Average heart rate is the average of heart rates measured during an exercise period. A Polar heart rate monitor will calculate the average by sampling actual heart rate in beats per minute at regular and frequent intervals throughout the duration of an exercise session. What is Resting Heart Rate? Resting heart rate is the number of beats measured in one minute while at complete rest. This number is an indicator of your basic fitness level. When your fitness level is increased, your heart will require less effort and fewer beats per minute to pump blood to the rest of your body. The best time to determine a resting heart rate is immediately after waking (without an alarm) and before getting out of bed. Resting heart rate measurements should be taken for 5 consecutive days for an average to be determined. This average number will reflect your actual resting heart rate. Resting heart rate is dependant on a range of different factors including: quality of sleep, stress, heat, overtraining and eating/drinking habits. First Australian Rights Pursuit Performance © 2014 8 What is the Difference Between Heart Rate in Beats Per Minute (bpm) and Percentage (%) of Maximum? A Polar heart rate monitor can display heart rate in beats per minute or as a percentage of maximum heart rate. Displaying heart rate as % of max HR makes it easier to know immediately which heart rate zone your client is training in. For example, a personal trainer could send a group of clients out for a 6 km jog at a heart rate range of 70-80% of maximum heart rate and each participant will be able to individually train within their personalised heart rate zone but achieve the same benefit. What is Maximum Heart Rate? Maximum Heart Rate (Max HR) is the highest number of times the heart can contract in one minute. Max HR is the most useful tool in determining training intensities, because it can be individually measured or predicted. Factors influencing max heart rate: Type of activity (sport/muscle group specific). Ageing process. Exercise history. Genetics. Determining a Maximum Heart Rate There are three ways to determine a maximum heart rate: VO2max. Sub maximal heart rate test. Age predicted maximum heart rate formula. VO2Max VO2max is the maximum capacity of the body to transport and utilise oxygen during incremental intense exercise. It is measured as millilitres of oxygen used in one minute per kilogram of body weight. Accurately measuring a VO2max involves a physical effort sufficient in duration and intensity to fully tax the aerobic energy system. In general this test is performed on a treadmill or stationary bike in a laboratory or sports institute. The exercise intensity is progressively increased while measuring ventilation, oxygen and carbon dioxide concentration of the inhaled and exhaled air. VO2max is reached when oxygen consumption remains at steady state despite an increase in workload. As a result, this test is extremely strenuous and must be performed under the instruction of an exercise physiologist or doctor. VO2max tests are generally considered the best indicator of an individual's cardiovascular fitness and aerobic endurance. Theoretically, the more oxygen used during high level exercise, the more energy can be produced. First Australian Rights Pursuit Performance © 2014 9 The above diagram demonstrates the differences in an individual with a low level of fitness compared to someone with a high level of fitness. The diagram on the right shows a much higher level of oxygen being produced, transported and utilised by the body which therefore leads to a more efficient cardiovascular system and increased fitness level. Sub Maximal Heart Rate Test A sub maximal test is not as specific as the maximal heart rate test however it is more individual than the age based formula and it can be performed readily in the field. Example 1: Running Ensure the Polar heart rate monitor is set to display heart rate in beats per minute (rather than in % of Max HR). Your client must first perform a 15-20 minute warm up with their heart rate gradually reaching 85% (i.e. age based Max HR x 0.85). Now, on a running track or other open environment, get your client to perform a 2 minute run at maximal effort, recover for 2 minutes (either remain stationary or slow walk) and then perform a second 2 minute run at maximum effort. Take note of the highest heart rate value reached either in the first or second interval and add 5 additional beats to the highest value. This number can now be used as their maximum heart rate. Example 2: Cycling Ensure the Polar heart rate monitor is set to display heart rate in beats per minute (rather than in % of Max HR). Your client must first perform a 15-20 minute warm up with their heart rate gradually reaching 85% (i.e. age based Max HR x 0.85). Now, at the base of a hill which has a steady gradient of approximately 4-5%, get your client to perform a 3-4 minute seated climb at maximal effort, in a gear that allows you to maintain a cadence of 60-70rpm. Take note of the highest heart rate value reached either in the first or second interval and add 5 additional beats to the highest value. This number can now be used as their maximum heart rate. First Australian Rights Pursuit Performance © 2014 10 Age Predicted Maximum Heart Rate Formula The age predicted maximum heart rate formula is a simple way to get an estimate of a maximum heart rate with some accuracy in adults. It is an extremely safe and effective way to establish a training zone for beginners and individuals training for a healthier lifestyle or for recreational sport. The formula used to identify the age predicted maximum heart rate is: 220 - Age = age predicted Max HR Example: The age predicted Max HR for a 26-year-old 220-26 years = 194 bpm (beats per minute). You should remember that there may be some discrepancy when using the age-predicted formula, especially in those who have been fit for many years or older people. The formula will give an estimate to work from, but if you want to know exact measurements, then a maximum heart rate test should be performed under the supervision of an exercise physiologist. First Australian Rights Pursuit Performance © 2014 11 What is a Target Heart Rate Zone? A target zone is a heart rate range that will guide your client through their workout by keeping their intensity level between an upper and lower heart rate limit. There are various recommended target zones that correspond with achieving specific exercise goals. For example, if your client would like to improve their aerobic power and ability to complete longer intensity efforts, then Zone 70-80% of max heart rate should be their main focus. Factors that Affect Heart Rate There are many factors that can affect heart rate. They may include: Personal Age: Maximum heart rate declines with age in sedentary individuals at a greater rate than in fit people. Gender: Generally women have a faster heart rate than men. Genetics: Maximum heart rate is predetermined by genetics. Exercise Fitness level: The fitter the individual, the less often the heart contracts therefore reducing their resting heart rate. Resting heart rate: The fitter the individual, the quicker the heart rate will return to their resting rate after exercise. Situation Exercise type: The type of exercise will greatly determine what maximal heart rate is achievable. The greater the quantity of muscle mass used for the exercise, the higher the training heart rates attained. The highest heart rate numbers are those from sports which use both lower and upper muscle groups simultaneously such as cross country skiing. The lowest are those in which the body is in a horizontal position or in cool temperatures such as swimming. Exercise intensity: The greater the intensity, the higher the heart rate. Body and environmental temperatures: Heat increases heart rate by boosting the metabolic rate of heart cells. Cold temperatures have the opposite affect; they directly decrease heart rate. Exercise environment: Training both indoors and outdoors can affect heart rate. Training indoors provides a much more predictable environment as opposed to outdoors where you may be faced with many factors such as extreme temperatures, wind and terrain changes. All of which can greatly alter heart rate during exercise. Stress Physical/Emotional Stress: Heart rate is affected by external stresses on the body such as heat, humidity, cold, wind, altitude and air quality. Intense emotional stress can also cause a raised heart rate and place tension on arteries, causing damage to them. As the body heals this damage, artery walls scar and thicken, which can reduce the supply of blood and oxygen to the heart. Nutrition: Rapid changes in blood chemistry such as blood sugar levels, and/or reactions to different types of ingested foods can both lower and raise resting and exercising heart rates. Dehydration: Dehydration is an excessive loss of fluid from the body. When there is less fluid, there is less blood. When there is less blood volume, the heart needs to pump faster, therefore increasing heart rate. Medication: Medications can affect the function of the heart in three main ways, they can affect: 1. Force of contraction. 2. Frequency of the heart beat. 3. Regularity of the heart beat. 4. Some medications can decrease heart rate while others will increase it. Smoking/Drinking Habits: Alcohol is a drug that depresses the central nervous system and therefore reduces short term heart rate. Cigarette smoking on the other hand increases heart rate due to the constriction of blood vessels which forces the heart to work harder to deliver oxygen to the rest of the body. First Australian Rights Pursuit Performance © 2014 12 Energy Pathways A basic understanding of how the body uses energy during different forms of exercise is critical when designing an effective exercise program. We will focus on the energy systems and how the body utilises fat, carbohydrate, and protein to produce energy, and how these energy systems are relied upon during different forms of exercise. The amount of each fuel - carbohydrate, fat and protein - used during exercise depends on a wide range of factors: Dietary intake. Fitness level. Type of exercise. Training intensity. Length of workout. Frequency of training sessions. Adenosine Triphosphate (ATP) is a complex chemical compound formed with the energy released from food and stored in all cells, particularly muscles. The body cannot easily store ATP, therefore it is necessary to continually create ATP during exercise. There are two major ways in which the body can do this: 1. Aerobic metabolism (with oxygen). 2. Anaerobic metabolism (without oxygen). Fats and carbohydrates are the major fuel source for aerobic exercise. The balance of the use of these fuels is dependant upon exercise intensity and duration. At a high intensity the main source of energy is carbohydrates and at a low intensity it is fat. As there is a limit to the amount of carbohydrate that can be stored in the muscles, high intensity work can only be sustained for short periods of time. In contrast, we have large stores of fat and so low intensity work can be maintained for long periods of time. The above diagram demonstrates the differences that exercise intensity has on calorie usage from the major fuel sources. With appropriate training these energy systems can adapt and become more efficient to enable greater exercise durations at higher intensities. Anaerobic Metabolism: ATP-PC System Fat, carbohydrates and protein are converted into energy in the form of Adenosine Triphosphate or ATP. The energy released by the breakdown of ATP allows muscle cells to contract. ATP is stored in relatively small amounts in muscle cells; only to last for a few seconds during maximum effort. Because the supply of ATP within muscles is small, metabolic pathways that lead to resynthesis of ATP must be activated to keep up with the demands for continued muscle contraction. Once ATP runs out, the body uses the high energy molecule, phosphocreatine (PC) to resynthesise ATP. After the ATP and PC stores are depleted, the body will move on to either aerobic or anaerobic metabolism (glycolysis) to continue to create ATP to fuel exercise. The ATP-PC energy pathway supplies up to 10 seconds worth of energy and is used for short bursts of exercise such as a 100 meter sprint. First Australian Rights Pursuit Performance © 2014 13 Anaerobic Metabolism: Lactic Acid System / Glycolysis Anaerobic metabolism (glycolysis) creates ATP from carbohydrates, producing lactic acid as a by-product. This anaerobic pathway provides energy by the (partial) breakdown of glucose without the need for oxygen. Anaerobic metabolism produces energy for short, high-intensity bursts of activity (such as sprinting, high jump and hurdling) which will last no more than several minutes before lactic acid begins to build-up reaching the lactate threshold. This build up of lactic acid interferes with the muscles ability to contract and hinders energy production - causing fatigue, muscle pain and poor performance. Aerobic Metabolism Aerobic metabolism fuels most of the energy needed for endurance exercises such as long distance running and cycling. This energy system uses oxygen to convert the main nutrients: carbohydrates and fats into ATP. This system requires the circulatory system to transport oxygen to the working muscles before it creates ATP. During a training session, we often move through all of the energy pathways. As we begin, ATP is produced via anaerobic metabolism. When breathing and heart rate begin to increase, more oxygen will become available enabling aerobic metabolism to begin. This will continue until the lactate threshold is reached. If this threshold is exceeded, the body can not deliver oxygen quickly enough to generate ATP, therefore anaerobic metabolism will again begin. As we have learnt, the lactic acid system only lasts for a short period of time because of a build up of lactic acid in the body. Therefore continuing at this intensity is not sustainable and the individual will need to decrease their intensity to remove the lactic acid from their muscles. Metabolism Metabolism is the process by which the body converts food into energy. Calories from carbohydrates, fats and proteins are combined with oxygen to release the energy the body needs to function. The number of calories the body burns each day is called "total energy expenditure". This calorie requirement is influenced by the following: Basal Metabolic Rate (BMR) BMR is the large amount of calories used as fuel for organs, breathing, circulating blood, adjusting hormone levels, plus growing and repairing cells. Food Processing Requires a small amount of daily calories for digestion, absorption, transportation and storage. Physical Activity Physical activity accounts for the remainder of calories used. It is possible to control the number of calories burned depending on the frequency, duration and intensity of exercise. (Calorie expenditure during exercise can be monitored by all current Polar heart rate monitors) Many factors influence the calorie requirements and expenditure of an individual, including body size and composition, age, and gender. Body size and composition: A larger body requires more energy from calories than a smaller person. Muscle will burn more calories from fat, therefore the higher the muscle mass, the higher the Basal Metabolic Rate (BMR). Age: As we get older, the amount of muscle tends to decrease and fat accounts for more of our weight. This will therefore slow the rate of metabolism and lessen the rate of calorie expenditure during exercise. Gender: In general men will have less body fat and more muscle mass than women of the same age and weight. With more muscle mass, a person will tend to burn calories faster. This is why men generally have a higher basal metabolic rate and burn more calories than women do. First Australian Rights Pursuit Performance © 2014 14 The Secret to Training Success By training to a well designed program, we start to stress or overload the body. With strategic recovery periods between training sessions, the body will be able to adapt and make itself fitter and stronger. The heart and lungs will become stronger and more efficient in delivering oxygen and eliminating waste. The skeletal muscles will become better at extracting oxygen from the blood and within muscle cells. All of these anatomical changes occur over time. In order for these changes to continue to improve, the body must continue to be overloaded through increases in volume, frequency or intensity. The Super Compensation Curve Figure 4: The Super Compensation Curve Figure 4 above demonstrates the stages the body goes through following a training session. Stage 1 on the graph shows the individual at their current level of strength and recovery. Throughout the session the individual becomes increasingly fatigued as the body's systems are placed under stress. Stage 2 demonstrates the recovery period. Throughout this stage it is essential for the individual to rest, recover and regain lost strength in preparation for the next training session. During this stage or the 'super compensation stage', the body increases in size and strength beyond its original starting point. At this optimal point, the body will reflect a maximum level of strength and readiness and be more capable to deal with the demands of the next training session. Stage 3 and 4 demonstrates the next training session and the progression as the cycle starts again. If an individual begins to train again before their body has fully recovered and before they have reached their optimal point of recovery, they may enter a stage of detraining. Figure 5 Figure 5 above demonstrates detraining caused by a lack of adequate recovery between training sessions. Detraining is one of the biggest reasons for poor results, injury and drop out. Figure 6 below demonstrates the stages of an individual who is training in the ideal zone, allowing for adequate recovery. You will notice an improvement in their performance over time. First Australian Rights Pursuit Performance © 2014 15 Figure 6 First Australian Rights Pursuit Performance © 2014 16 Overtraining Overtraining occurs when the individual is exercising too hard, for too long, with insufficient recovery time between training sessions. The body will therefore not have time to repair and regenerate which can lead to ongoing fatigue, poor results, injury, decreased motivation and drop out from exercise programs. The signs and symptoms associated with over training are due to changes in the function of the autonomic nervous system, hormonal status, immunological parameters and other physiological and musculoskeletal changes of the body. Examples of overtraining signs and symptoms: Depression, irritability, bad mood, anxiousness, confusion, excitement, desperation, lack of concentration. Unwillingness to train, feeling of inability to go on training and decreased performance. Sleeping problems and fatigue. Bad appetite. Shaking hands. Abnormal sweating. Palpitations. Nausea. Dizziness. Increased resting and sub-maximal heart rate (resting heart rate can also decrease in overtraining state). Muscle soreness. Decreased maximal heart rate. Menstrual irregularities. Loss of strength and co-ordination. Increased illness and injury frequency. Heart Rate Reactions in Overtrained Athletes Recovery from severe overtraining can take weeks or even months. Therefore it is important to diagnose overtraining early. Measurement of heart rate and heart rate variability (Polar R-R interval measurement) has proven to be the best way to identify the initial state of overtraining. What is Heart Rate Variability? Heart rate variability (HRV) refers to the beat-to-beat differences in heart rate. Under resting conditions, a healthy individual will exhibit periodic variation in R-R intervals. The greater the time difference exhibited between beats, the healthier you are. Maintaining a certain degree of HRV is essential to overall health. The diagram below demonstrates the reduced variation in time between each beat as heart rate is increased. By raising the intensity of the exercise you will notice the differences in variability within the three heart rate examples. The higher the heart rate, the less variability between the beats. First Australian Rights Pursuit Performance © 2014 17 By accurately measuring the time interval between heart beats, the detected variation can be used to measure stress and fatigue on the body during training. Generally, the more relaxed and rested the body is, the more variable the time between heart beats. An overtraining condition must always be taken seriously. It can be difficult to diagnose the cause of an overtraining condition. It may have long term and sometimes even permanent consequences, such as fatigue and continual injury. Some athletes never reach their former peak performance level after an overtraining condition. Training at the wrong intensity or with inadequate recovery may lead to poor progression, staleness, burnout and injury. 5 Ways to Avoid Overtraining 1. Ensure your client knows their body and understands when they have reached the peak of their curve. Recovery time can vary depending on the time and type of training session. Higher intensity and/or more physically challenging sessions require a longer recovery period. These sessions can include: High Intensity Interval Training (HIIT) and Long Slow Distance (LSD). 2. Exercise at lower intensities for shorter periods of time will generally require less recovery time. These sessions may include: 30 minute jog or a game of social touch football. First Australian Rights Pursuit Performance © 2014 18 The above graph demonstrates the recovery time needed and the optimum time for the next training session for light, moderate and hard exercise sessions. 3. It is a good idea to alternate training sessions using the hard / easy principle. This means following a hard training session with an easier or recovery session. For example, after completing a HIIT session of 8 x 1 minute intervals at 85-95% of your maximum heart rate with 1 minute recovery between intervals, the next training session may be an easy jog at an intensity of 60-80% of maximum heart rate for 30 minutes. The hard/easy principle will allow the body to rest and recover between training sessions and prevent overtraining. 4. Encourage your clients to monitor their resting heart rate each morning. Any marked increase from the norm may indicate that the individual is not fully recovered. 5. Document the heart rates of your clients over time during a certain aerobic activity at a specific intensity and speed throughout the training. If their pace starts to slow, and the exercise heart rate increases, they may be heading towards overtraining. First Australian Rights Pursuit Performance © 2014 19 Target Heart Rate Zones Whatever your client's goals are - improving overall health, weight management or winning athletic competitions - it is possible to eliminate guesswork by exercising within a specific target heart rate zone using a Polar heart rate monitor. The secret to exercising effectively and efficiently is to ensure that your client is working in the right heart rate zone for their exercise goals. In each zone their body will experience a different physiological effect and as a general rule, when exercise intensity is increased the duration of the activity or efforts should decrease. How Do You Work Out Your 5 Sports Zone Limits? To work out the 5 sports zones for your clients, you must first determine their maximum heart rate value by using one of the three methods discussed in determining your maximum heart rate. For example: 220-Age = Max HR (bpm) i.e. 220-25 = 195 bpm Once you know the maximum heart rate of your client, you can then determine each of the 5 sports zone using the following formula: Max HR (bpm) x chosen % of Max HR = HR bpm For example: 50% = 195 x 0.5 = 98 bpm. 60% = 195 x 0.6 = 117 bpm. 70% = 196 x 0.7 = 137 bpm. 80% = 195 x 0.8 = 157 bpm. 90% = 195 x 0.9 = 176 bpm. 100% = 195 x 1.0 = 195 bpm. Polar Sports Zones All Polar heart rate monitors have the ability to set a target heart rate zone. The monitors are fitted with a visual warning and audible alarm that activates when your client begins to exercise outside this zone. The Benefits and Effects of the Individual Sports Zones Training heart rate 50-60% of Max HR Good for recovery sessions. Used for warm ups and cool downs. First Australian Rights Pursuit Performance © 2014 20 Training heart rate 60-70% of Max HR Improves the heart's ability to pump blood. Increases the number of small blood vessels in your muscles. Increases the enzymes in the muscles responsible for oxygen metabolism. Increases the strength of muscles, tendons, ligaments and bones. Improves endurance. Burns fat as the body's main energy source at this intensity. Training heart rate 70-80% of Max HR Accustoms the body to a faster pace. Improves endurance. Begins to increase the speed that can be maintained without building up lactic acid. The higher the fitness level, the greater the percentage of fat the body uses as fuel, enabling you to perform longer at this rate while preserving limited stores of glycogen. Training heart rate 80-90% of Max HR At this intensity, the body will begin to work anaerobically and build up lactic acid before reaching anaerobic threshold. Increases fitness level due to an improved anaerobic threshold. This intensity can be maintained for about one hour in competition. Training heart rate 90-100% of Max HR Used during sprint training and racing over short distances (track sprinters, short-distance swimmers etc). Used during High Intensity Interval Training sessions (HIIT). First Australian Rights Pursuit Performance © 2014 21 Planning a Training Program Most people have limited time for training each week but a Polar heart rate monitor allows you to make the most of each training session. You will be able to train more efficiently within a limited time and gain an advantage over those who may have more time available but less knowledge about their body during certain exercise phases. Guidelines For Planning a Training Program Set clear and realistic goals for your clients. Determine how much time they can spend training within a week. Determine how much time they can allocate in order to achieve their particular goals. Determine their maximum heart rate and personalised heart rate zones. Design a clear and concise training program consisting of a variety of work in each sports zone. Consider the following: How often will they need to exercise? (Frequency) How hard will they need to work? (Intensity) How long will each session be? (Time) What type of exercise will they do? (Type) Will the session be continuous, combination or interval? Design a training log so your client can record their progress. Record the session volume and intensity, body weight, heart rates, time trials and tests completed. Be flexible with planning and don't be afraid to make changes if needed. Your client's program should be designed to enhance their lifestyle. Achieve goals and have fun. Structuring a Training Program Adherence to certain basic exercise components is important for developing an effective program. It is important to structure a cardiovascular program to ensure it includes an effective warm up and cool down. Warm up: Complete a 5-15 minute warm up at the beginning of every exercise session. The purpose of the warm up is to increase heart rate, blood pressure, oxygen consumption, elasticity of the muscles, heat produced by the muscles and dilation of the blood vessels. Any aerobic activity done at very low intensity can serve to warm up the muscles, tendons, and ligaments. For example walking, light jogging and cycling in a heart rate zone of 50-70% of Max HR. The intensity of the warm up should begin at a low level and gradually build to the level of intensity required during training. Cool Down: During the cool down phase your clients should slowly decrease the intensity of cardiovascular activity. This will keep the body circulating blood and preventing blood from pooling in the veins. A cool down should last around 5-15 minutes depending on the time and intensity of the training session, generally working at around 50-70% of Max HR. First Australian Rights Pursuit Performance © 2014 22 The Training Method There are four major types of training you can use to help increase your client's cardiovascular conditioning. They are continuous, interval, fartlek and circuit training. Continuous Training Continuous exercise helps to condition the cardiovascular system. This type of exercise may include walking, jogging, cycling, swimming and aerobics. Continuous training should be performed at an intensity between 60-80% of max heart rate. Key Benefit: With this method of training, your client will notice significant fitness improvement and fat loss. Continuous training should be the main focus for individuals with cardiovascular risk factors such as high blood pressure and cholesterol. Interval Training Interval training consists of mixing more intense periods of exercise with less intense periods of exercise within one session. Interval training is a useful training method for improving conditioning and performance levels. Beginner example: A brisk walk at 60-70% of max heart rate for 3 minutes followed by a slow walk at 50-60% of max heart rate for 3 minutes. Repeat 5 times. It is important for beginners to begin slow and gradually increase the intensity and duration of their intervals over time. Intermediate example: Stationary cycling at 70-80% of max heart rate for 3 minutes followed by an easy pace at 60-70% of max heart rate for 3 minutes. Repeat 5 times. Advanced example: Sprinting at 85-95% of max heart rate for 30 seconds followed by 90 seconds of walking at 60-70% of max heart rate. Repeat 10 times. Key Benefit: This repetitive form of training leads to the adaptation response. The body begins to build new capillaries and becomes more efficient in taking in oxygen and delivering it to the working muscles. The muscles will develop a higher tolerance to the build-up of lactic acid and the heart muscle will strengthen. Fartlek Training Fartlek (speed play) training is a form of conditioning at varying speeds and intensities. It places stress on both the aerobic and anaerobic systems. Fartlek training is quite similar to interval training; however the work/rest intervals are not measured to any degree. The great thing about this type of training is that it can be performed by a person of any fitness level. Most fartlek sessions last a minimum of 45 minutes and can vary from aerobic walking to anaerobic sprinting amongst many other kinds of exercise. Example: gentle warm up jog for 5-10 minutes then significantly vary your pace every 5-10 minutes between 60-80% of max heart rate. Key Benefit: Fartlek training can be used by people of all levels of fitness, from complete beginners to advanced Olympic athletes. Fartlek training can be adapted to the training needs of any activity or sport. First Australian Rights Pursuit Performance © 2014 23 Circuit Training Circuit training takes a person through a series of different exercise stations with a short recovery time between the stations, usually around 15-30 seconds. The number of stations is generally between 5-10 and includes exercises such as weight training, aerobic work and body weight exercises. Key Benefit: Circuit training offers a lot of variety, challenges the skills of the participants and keeps them interested from session to session. It also allows them to work their aerobic system while simultaneously working on their strength. First Australian Rights Pursuit Performance © 2014 24 Client Scenarios and Basic Guidelines The following client categories are examples of the common types of clients you may come across in the fitness industry. It is recommended that all individuals visit their doctor prior to the commencement of any exercise program to have their health assessed. The Weight Loss Client Jenny is a 39 year old mother of two. She works full time as a marketing co-ordinator for a small company close to her home. Jenny has struggled with her weight since she had her first child. She is tired of feeling overweight and unfit and wants to lose weight for her 40th birthday in 6 months time. Jenny has not exercised regularly since she was in her early 20's. Fortunately, Jenny has no medical issues that could prevent her from exercising. It is important for Jenny to build a base level of fitness before she undertakes intermediate or advanced training techniques. Therefore, she will need to spend most of her training time doing continuous cardiovascular exercises within a heart rate zone of 60-70% of her maximum heart rate with the occasional session at 70-80%. It is important to get Jenny to exercise almost every day for 30-60 minutes. The types of activities she may do include light to moderate jogging, swimming, walking, cycling and aerobics. After approximately 6-8 weeks of working in this base level zone you may then begin to vary Jenny's program. This variation may include some basic interval and circuit training sessions in a heart rate zone of 70-80%. However the majority of Jenny's training week will still be spent within 60-80% of her maximum heart rate. The Cardiac Rehabilitation Client Adrian is a 50 year old gardener who has recently undergone bypass surgery on his heart. He has been given the all clear from his doctor to begin an exercise program. Adrian is overweight and has high blood pressure. His doctor has insisted that he needs to lose weight and reduce his blood pressure naturally through exercise. Adrian plays a round of golf every now and then but he is quite unaccustomed to cardiovascular exercise. When dealing with this type of client it is essential for the trainer to know their exercise limits, which activities will suit them best and what needs to be avoided all together. This information is best sourced from the client's doctor. It is essential for Adrian to develop a base level of fitness. He needs to strengthen his cardiovascular system through light continuous aerobic work. The intensity of this training should be dictated by Adrian's doctor. This initial level of training will get Adrian working in around 50-70% of his maximum heart rate. He must start with an exercise duration which feels comfortable, such as 10-20 minutes. This duration can be gradually increased over time depending on how Adrian is responding. Adrian's exercise program should run between 3-7 times per week depending on recovery. These sessions should include light cardiovascular activities such as swimming, walking, cycling and gentle aerobics. It is important to make sure Adrian progresses comfortably and maintains good contact with his doctor. He must also follow any recommendations made by the doctor in regards to the progression of his program and heart rate limits. As his fitness level begins to increase and his heart becomes stronger, gradually increase the duration and intensity of the sessions and combine different training methods such as circuit and interval training. First Australian Rights Pursuit Performance 2014 25 The Improving Fitness and Lifestyle Client Craig is a 25 year old school teacher who loves working out and keeping fit. His goal is to be able to run comfortably and perhaps do a fun-run later in the year. Occasionally Craig lacks a bit of motivation and so he has decided to see a personal trainer to break up his training routine. Most of Craig's training consists of spin classes and high intensity kick boxing sessions. Craig's base fitness is reasonable but it is likely with this type of training that he spends too much of his training week in his anaerobic sports zone i.e. 80-90% or 90-100% of his maximum heart rate. We need to add a couple of continuous cardiovascular sessions in to his program in which his heart rate remains between 60-80% for around 30-60 minutes to develop a more efficient cardiovascular level of fitness. Over time we will gradually increase the distance or time of these continuous aerobic sessions plus once a week Craig will need to do a long distance run. Once or twice a week Craig will also do a high intensity interval training (HIIT) session. This will challenge his anaerobic system in order to improve his ability to run longer distances. Craig should aim to train around 3-6 days per week. The Pregnancy Client Bec is a 27 year old who is 3 months pregnant with her first child. She has always kept herself fit and loves to go to the gym. She doesn't want to lose her figure and put on too much weight while she is pregnant. So she wants a program she can maintain during her pregnancy and after the birth. Because Bec has always exercised throughout her life, much of her program will remain the same as prior to her pregnancy. However it will be important for her to monitor how she feels and if activities begin to become uncomfortable then she may need to slow down or stop. Most of Bec's training will consist of light to moderate cardiovascular exercise at around 50-70% of her maximum heart rate for 20-60 minutes or unless otherwise stated by her doctor. During the initial stages of her pregnancy, Bec may be able to exercise as much as 5 days a week but as the pregnancy progresses she may feel her body requires more recovery. Activities that may be appropriate for Bec include low impact activities such as walking, light jogging, swimming, aqua aerobics etc. After Bec has had the baby, she should be able to continue with this low impact training program until she feels her body has sufficiently recovered and she feels comfortable enough to increase the number of sessions. When she gets to the point where she wants to increase her training routine, her trainer should re-asses her program based on her new goals. First Australian Rights Pursuit Performance 2014 26 The Athlete Karen is a 28 year old state netball player. She trains 5 nights per week to maintain her fitness level. The team has state titles coming up in 3 months and Karen wants to be able to perform at her best. Karen has decided that she needs to improve her endurance throughout the game. She wants to be able to sprint fast and strong throughout the entire match. Karen has decided to seek some help from a trainer at her local gym. Due to Karen's reasonable base fitness level and the short time frame before the state titles, she is going to focus her training twice a week in the hard to maximum sports zones. These sessions will involve spending 1-5 minutes at 85-95% of her max heart rate followed by recovery to 60% and then repeated 5-10 times. It is important that Karen spreads these sessions out throughout the week to ensure she gets sufficient recovery. To increase the intensity of these sessions, she can increase the time of each interval or the number performed. First Australian Rights Pursuit Performance 2014 27 Monitoring Improvement It is important to record training sessions, track results and monitor improvements. Measuring this improvement can be done in the following ways: 1. Develop a test exercise to repeat every 4th week (distance is best). For example a 6 km run test with your heart rate maintained between 82-85% of max. Record the time taken to complete the full distance. Record the time and average heart rate at each 1km increment. Record the minimum, maximum and average heart rate for the entire 6 km. Figure 7: 6 km run test graph Figure 7 is a recording of a 6 km test with the average heart rate taken after each kilometre. 2. Record rates of recovery within a workout Recovery rate during intervals. Recovery rate at the end of the session. First Australian Rights Pursuit Performance 2014 28 3. Record resting heart rate decreasethe mayPolar indicate an aerobic improvement. 4.APerform Fitness Test to identify a level of fitness. AnPolar increase mayTest indicate or fatigue. The Fitness uses an theillness individual's gender, age, height, weight, level of physical activity, heart rate and heart rate variability to measure and record their fitness level. The test lasts no more than 5 minutes and is performed at rest. Figure 8 is step by step instructions on how to perform the Polar fitness test. Figure 8: Polar Fitness Test Once completed, the Polar Fitness Test shows the fitness level as a number. The result is comparable to VO2max, the same indicator of aerobic fitness used by professional trainers and athletes. Typical values for unfit sedentary individuals are around 25. Top athletes usually score values above 70 (men) and 60 (women). See the results table below (Figure 9). First Australian Rights Pursuit Performance 2014 29 Figure 9: Fitness Classification Table First Australian Rights Pursuit Performance 2014 30 Safety Polar heart rate monitors have been developed to measure healthy people's heart rate. People with medical conditions that affect their heart rate, limits their exercise capacity or have not exercised regularly should consult a doctor before beginning a regular exercise program. These conditions may include: High blood pressure High blood cholesterol Signs or symptoms of any disease Recovery from a serious illness or a medical treatment e.g. surgery Usage of a pacemaker or other implanted electronic device Pregnancy Injury Further Reading To further your understanding of developing and performing more advanced heart rate training sessions, refer to Polar Education Zone: Advanced Heart Rate Training. First Australian Rights Pursuit Performance © 2014 31 References Marieb, EN 2006, Essential of Human Anatomy and Physiology, San Francisco Edwards, S 1999, The Heart Rate Monitor Guidebook to Heart Zone Training, Australia Craig, N 1996, Scientific Heart Rate Training, Australia Diemen, AV, Bastiaans JJ 2004, Performance Cycling, Finland Burke, ER 2003, Precision Cycling, Finland Browning, R 2004, Multisport, Finland Fenton, M, McGovern D 2005, Precision Walking, Finland Wright, P "How to avoid overtraining", Fitness First Magazine, The Smart Issue, March / April 2009 Edition, pp.23-24. Polar USA 2009, Heart Rate Training Articles, Viewed 1st April 2009, http://www.polarusa.com http://www.howtobefit.com/heart-rate-basics.htm http://www.howtobefit.com/heart-rate-during-pregnancy.htm http://www.howtobefit.com/weight-loss-heart-rate.htm http://www.howtobefit.com/why-heart-rate-monitors.htm Polar Personal Trainer 2008, viewed 1st April 2009, http://www.polarpersonaltrainer.com Cyphers, M 1991, Personal Trainer Manual, The Resource for Fitness Professionals, Fitzones, viewed 1st April 2009, http://www.fitzones.com/members/Fitness/fitness.asp Edwards, S, Heart Zones Training and Education Company, viewed 1st April 2009, http://www.howtobefit.com/determine-maximum-heart-rate.htm http://www.howtobefit.com/five-heart-rate-zones.htm http://www.howtobefit.com/heart-rate-training-zones.htm Polar Electro, Exercise and Heart Rate, viewed April 2009, http://www.howtobefit.com/exercise-and-heart-rate.htm http://www.howtobefit.com/hearts-function.htm http://www.howtobefit.com/measure-heart-rate.htm http://www.howtobefit.com/ownindex-polar-fitness-test.htm http://www.howtobefit.com/polar-overtraining-test.htm http://www.howtobefit.com/weight-loss-heart-rate.htm Fletcher, E 2009 "Heart Rate Variability", JDS Sports Coaching, Peak Performance Newsletter, issue 237, viewed 16th June 2009, http://www.jdssportcoaching.com/default/index.cfm/resources/physical-tuning/heart-rate-variability/ First Australian Rights Pursuit Performance © 2014 32 Glossary of Terms Adenosine Triphosphate (ATP): A phosphate molecule which is used to release energy for work within the body. Basal Metabolic Rate: a measurement of energy required to keep the body functioning at rest. Cardiac output: The amount of blood that is pumped out of the heart from one ventricle in one minute. Cardiovascular fitness: the ability of the heart and lungs to supply oxygen-rich blood to the working muscles and the capacity of the muscles to use oxygen to produce energy for movement. Creatine Phosphate: A high energy phosphate molecule that is stored in cells and can be used to re-synthesize ATP immediately. ECG: a medical test that detects cardiac abnormalities by measuring the electrical activity generated by the heart as it contracts. Fartlek training: a form of conditioning which puts stress mainly on the aerobic energy system. Glycolysis: a metabolic process that breaks down carbohydrates and sugars through a series of reactions. Heart rate: the rate at which the heart beats. Maximum Heart Rate (Max HR): the highest number of times the heart can contract in one minute. Metabolism: the process by which the body converts food into energy. Pericardium: a double-layered membrane surrounding the heart. Pulse: the beating of the heart felt as throbbing of the arteries when compressed against a bone. Resting heart rate: is the number of beats in one minute when an individual is at complete rest. Sinus node (SA): sends out electrical signals causing the atria to contract. Stroke volume: the amount of blood the heart can pump out in one beat. Super compensation: Demonstrates the stages the body goes through following a training session. VO2 Max: the maximum capacity of an individual's body to transport and utilize oxygen during incremental exercise, which reflects the physical fitness of the individual. First Australian Rights Pursuit Performance © 2014 33