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PD/H/PE Factors Affecting Performance How does training affect performance? 1. Energy Systems The energy source for the body is ATP, when the third phosphate molecule is split, heat and energy are released due to the breaking of high energy bonds and the third phosphate molecule has to be resynthesised. The body does this using 3 energy systems ATP/PC system (alactacid system) Intensity of effort: very high, 85-100% of max effort, explosive actions Duration: 10-12 seconds. ATP splitting (2sec) cretin-phosphate (8-10sec following) Fuel: Cretin Phosphate is fuel, only used after ATP has been used Waste Products: none Recovery Time: cretin phosphate is naturally replenished by the body in up to 2 mins Examples: 100m sprint, weight lifting, discus, javelin, high jump Lactic Acid (Anaerobic Glycolosis, Lactate System) Intensity of effort: 75-85%. This is the point at which lactic acid is produced Duration: varies, if working at 85% 30 secs, if working at 60% up to 30 mins, but usually 2-4mins Fuel: glycogen (carbohydrates are broken down in the body blood glucose glycogen) Waste Products: lactic acid Recovery Time: 30mins-1hr to break down lactic acid, if glycogen all depleted , it takes 24hrs to replenish glycogen stores Examples: 200m, 400m sprint, 100m swim, 800 run Aerobic System (Aerobic Glycolosis, Oxidative) Intensity of effort: low intensity, up to 75% Duration: at low intensity there is no limit because virtually unlimited fat stores, no limiting waste products as they are released, no real limit as we can switch to lactic acid Source of Fuel: Carbohydrates, fats, glycogen, protein Fuel: Carbohydrates, fats, glycogen, in extreme cases protein Waste Products: Carbon Dioxide which is breathed out, water which is removed from the body as sweat and water vapor, cooled as evaporated off skin Recovery Time: can take up to 48hrs depending on intensity Examples: marathon, long distance walking, netball triathlon Summary: energy systems should not be thought of as operating independently of one another. Although these systems have individual features they actually function together however given specific activities we can determine which energy system is the dominant energy system been utilized at a particular point in time. 2. Principles of Training Progressive Overload Implies gains in fitness will occur only when the training load is greater than normal and is progressively increased as improvements in fitness occur. Training produces certain physiological changes that allow the body to work at a higher level of intensity. As the body becomes familiar with a particular level of training stress, it adapts to it and further training at this level will fail to sufficiently stress the system. These adaptations will not take place if the load or resistance is either too big or too small. Too little resistance and the body won’t adapt, too much resistance and the person will fatigue or possibly incur an injury. This applies to aerobic fitness/activities, strength training and flexibility. Specificity Implies that the effects of a training program will be specifically related to the manner in which the program is conducted. The principle implies the greatest gains will be made when the activity in training programs resemble the movements in games and the activity. This is because the body adapts to stresses in a very specific was. Important when considering the development of energy systems, muscle groups and components of fitness. Metabolic Specificity: energy systems used in the activity should be developed through training. The effects of a training program are directly related to the nature of training performed. Specificity applies to all training components such as energy systems, muscle groups, muscle fibres and movement patterns. E.g. Aerobic marathon runner needs to target aerobic fitness Strength: increased leg power to improve ones ability to sprint, the training program must correctly address the speed, no. of repetitions, load and time between sets. Reversibility This implies that fitness gained can be lost just as quickly if fitness increased with activity and decreases with inactivity. The longer the build up of fitness, the slower the decline will be. Variety (cross training) Using the same drills and routines will not be productive as repetition without creativity leads to boredom. Mental well being is vital to maximize effort in physical training, cross training increases interest and motivation. Aerobic: swimming, running, cycling. Circuit Strength: Isometric, isotonic, Isokinetic Flexibility: static, dynamic Also leads to improvements in fitness Training Thresholds-the levels of intensity that can improve our physical conditions Aerobic Threshold: level of exercise intensity which is sufficient to cause a training effect. This a approximately 70% of a persons max heart rate Aerobic training Zone: a level of intensity which causes the heart rate to be high enough o cause significant training gains Anaerobic Threshold: a level of intensity in physical activity where the accumulation of lactic acid increases very quickly in the blood. Warm Up: Reduce the risk of injury by increasing Joint mobility (flexibility) Increase heart rate and body temperature Mental preparation Warm up should consist of: 1. General Body warm up e.g. jogging 2. Specific flexibility exercises (shouldn’t stretch cold muscles, flexibility >by 20% when warm) 3. Calisthenics-sit ups and push ups 4. Skill rehearsal Cool Down: Minimise muscle stiffness and soreness Help disperse lactic acid Prevent blood pooling Cool Down should consist of low intensity aerobic work and some stretching 3. Types of Training 1. Aerobic Training: uses the aerobic system as the main source of energy supply and includes training types such as: Continuous, Interval, Fartlek, Circuit training, Aerobics Aerobics- exercise performed to music combining strength, flexibility and cardio-respiratory fitness. It consists of a warm up, an extensive conditioning phase within the training zone for 20-30 mins and a cool down phase. Used to provide variety. Circuit Training- minimal aerobic capacity increase but significant increases in muscular endurance, strength and flexibility. Improves general conditioning by moving from activity to the next after completing required reps or in a certain time. Progressive overload is required to benefit such as increases stations, repetitions, time taken etc. Continuous- training without rest intervals, - Heart rate must be above the aerobic threshold and remain there for duration - E.g. jogging, cycling, swimming - Two types- long, slow distance training (general fitness) or high intensity of moderate duration (athletes) Fartlek- speed play, requires changes of speed in order to use aerobic and anaerobic energy systems. Continuous training with frequent bursts of speed every 2-3mins therefore training anaerobic and wee. Good for football, soccer, netball basketball etc which require an interchange of energy systems. Interval- involves alternating sessions of work and recovery. The player executes a given amount of work in a particular time and is then allowed a recovery period before the task is repeated many times. Players work hard but avoid fatigue. (Note higher intensity needs less duration) 2. Strength Training Strength is the ability of a muscle of group of muscles to exert a force against a resistance. Strength (resistance) programs can be divided into 3 categories. 2. Strength Training Guidelines for Effective Resistance Training Program Purpose Strength Power Lean Body Mass Muscular Endurance Weight Resistance Very Heavy 80-100% RM Medium 60-80% RM Heavy 70-90% RM light 40-60% RM Repetitions 26 Sets 36 Exercise Speed slow 2 10 36 fast 6 12 3 10 slow-medium 15 30 36 medium Time Between sets Long 35 Long 35 Short 13 Short 13 RM= repetition mass=the maximum a person can lift a specific number of times eg 80% RM =80% of the maximum weight that can only be lifted once Purpose Absolute+Relative Strength Weight Resistance Very Heavy 80-100% Speed Strength (power) Strength Endurance Lean Body Mass Repetitions 16 Sets 35 Exercise Speed slow -med Time Between sets up to 2mins Sessions per wk 3-4 days per wk Heavy 60-80% 2 10 36 fast 2-4mins 3-4 days per wk Light-medium 40-60% Medium-Heavy 70-90% 15 or > 36 medium minimal 3-4 days per wk 6 15 3 10 slow-med up to 2mins 3-6 days per wk ATP is made in mitochondria of muscle cells First release of energy comes from ATP splitting (high energy bonds) Lactic Acid system can last up to 30mins at low intensity above anaerobic threshold 1. Isotonic: The muscle length changes by lifting a constant resistance through a full range of motion. E.g. bicep curl. There are 2 types of isotonic contractions: a. Concentric: muscle length shortens b. Eccentric: downward, weight bearing and controlled, lengthening of muscles Muscles work in pairs-that is the agonist shortens in concentric contraction whilst antagonist lengthens 2. Isometric: Muscles develop tension but don’t change length. Isometric exercises will produce gains specific to the joint angle held 3. Isokinetic: This involves the use of elaborate machines-cybex. An Isokinetic machine automatically adjusts its resistance according to the force applied to it/exerted against it. Most useful for speed strength as if the movement was made as fast as possible the force will be maximal for the full range of movement-ideal for sprinting. These programs are useful for increasing muscle power, base of strength, increase muscle hypertrophy (size), rehabilitation, recovery from injury, increase muscle endurance, prevent injury. Strength gains will only be made if programs are exercise specific and apply the progressive overload principle. There are 4 types of strength 1. Endurance: ability of a muscle to repeat muscle contraction. Push ups, rowing, sit ups for extended amounts of time 2. Power: (speed strength) ability to apply force at a rapid rate. E.g. jumping, throwing 3. Absolute: maximum strength generated by a muscle. E.g. lifting the maximum weight possible, squeezing a hand dynamometer 4. Relative: maximum strength generated by a muscle relative to body mass. I.e. 80kg and 70kg person lift 100kg each. The 70kg person has higher relative strength. Training Program Comparison 100m Sprinter ATP-PC system Power Short recovery High intensity, interval Heavy power 60-80% of max Fast 3-6reps Warm up crucial Anaerobic threshold 3. Flexibility Training Endurance Road Cyclist Aerobic system Endurance Longer recovery Continuous-aerobic threshold, just above high end training zone Lactic acid system training Resistance-low weight High rep- >12-15, 40-60% weights Warm up not so crucial Aerobic threshold Flexibility is an important but often overlooked component of training. It is affected by age, gender, temperature and is greatly reduced after the age of 25. Muscles not only require strength they require length. Flexibility programs help prevent injuries, reduce muscle soreness and tightness following exercise, improve circulation, improve coordination and increase ROM therefore maximizing performance potential. Why Should I Stretch? When you contract a muscle, the muscles on the other side of the limb (antagonists) need to relax as they lengthen, if you are inflexible and your antagonists cannot fully relax they will begin to slightly contract to avoid being pulled or strained. This slight muscle contraction creates increased muscle resistance that your working muscles must overcome. This makes you more inefficient in regards to power output and energy consumption. When you multiply this inefficiency over a repeated exercise such as swimming, cycling and running, even over a shirt distance this becomes a significant performance barrier. Increase your ROM (Range of Motion) Range of motion is how far you can move your limbs around a joint. To correctly perform an event/action at high speed requires a good ROM. 1. Prevent Injuries Supple and adequately warm muscles are less likely to incur an injury, it is the antagonists that will suffer the strain otherwise i.e. hamstring when running 2. Improve Coordination Receptors located in muscles indicate where your limbs are in space and also contract the muscle when it becomes too stretched (to prevent injury). Increasing flexibility improves the threshold levels of these receptors so that they delay their reaction. Therefore you can contract your muscles harder, stretch them further and improve coordination before muscle receptors will interfere. 3. Improve Circulation Stretching warms muscles and increases blood flow thus improving circulation. As blood carries oxygen and oxygen is necessary to repair injured tissue, this will promote injury rehabilitation. Increased circulation from stretching will improve the rate of repair of unnoticeable micro tears (from training) as well as detectable injuries. Improved circulation will also promote the removal of waste products accumulated by training in the body such as lactic acid. This becomes an important factor when recovering between training sessions. Stretching also warms muscles and prepares them for activity. It will also create a slight rise in the body’s core temperature which also prepares the body for activity. There is a point at which increased flexibility gains will not result in improved performance therefore you should aim to ensure your ROM in each activity is sufficient to easily perform the motion correctly and you are flexible enough to prevent any antagonistic resistance during contractions. When do I Stretch? For greatest flexibility gains: stretch after you have finished training and incorporate it as part if your training session. This is the time to improve your flexibility while your muscles are very warm and slightly fatigued. Stretching at the end of a training session will also remove waste products from your system. Stretching prior to a training session: beneficial in preparing your muscles for the upcoming activity, but not the time to test flexibility. Actually an optimal warm up would involve light exercise for 10mins then stretching. Whenever Possible: is a good time to stretch (in the car, watching TV, before bed etc) this promotes circulation and aids recovery. Be careful not to overstretch How do I stretch? Ballistic (Dynamic) Stretching: involves bouncing where the muscle is taken to its end of range of motion, then overstretched by bouncing. This causes intramuscular damage (torn muscles) as a result of the ‘stretch reflex’. Ballistic stretching used not to be recommended due to its possible cause of injury however research has shown there is value from ballistic stretching if done with control and safely. Static Stretching: most common form of stretching which involves gradually moving the muscle into a position where you feel it begin to stretch and holding that position for a period of time (10-30secs). To get the full benefit from static stretching you should hold the position for a minimum of 8secs. Used for rehabilitation of injury as well as the warm up and cool down phases of training. Dynamic Stretching: suitable for speed and power sports which involves performing the activity while gradually increasing the ROM after you have commenced some light activity and completed a routine of static stretches. Dynamic stretching mimics the activity you are about to perform so it is very specific and also places the muscles under a similar load to the activity which static stretching doesn’t. E.g. run throughs, gradually increasing pace so you are fully warmed up, swim bands prior to swimming and gradually increasing the force applied Proprioceptor Neuromuscular Facilitation (PNF): designed to improve ROM and flexibility, muscles need to be adequately warmed first. PNF also requires another person. You begin by your partner stretching your muscles while you relax, your partner then holds your muscle in this position and you try to push against it as hard as possible for 3-5 seconds. After this your partner pushes your leg back again and it should go back further than the previous attempt. Static stretch followed by an isometric contraction then stretched statically again and usually involves the use of a partner. It is used in rehabilitation programs because isometric contractions strengthen the muscle fibres during the stretching process. - Determine muscle group While in stretch position, person isometrically contracts muscle (push against resistance) and holds for 10secs - Relaxes in lengthened position for 5secs - Further static stretch applied followed by isometric contraction Based on two principles: 1. muscle relaxes more fully after it has undergone a maximum isometric contraction implying it can be stretched further and resistance to stretching is reduced 2. A muscle becomes stronger if its antagonist is isometrically contracted immediately beforehand-good for rehabilitation. PNF will increase ROM 3 times faster than static or ballistic. Stretch Reflex: When the muscle is stretched, so is the muscle spindle. The muscle spindle records the change in length (and how fast) and sends signals to the spine which convey this information. This triggers the stretch reflex (myotatic reflex) which attempts to resist the change in muscle length by causing the stretched muscle to contract. The more sudden the change in muscle length, the stronger the muscle contractions will be. This basic function of the muscle spindle helps to maintain muscle tone and protects the body part form injury. One of the main reasons for holding a stretch for a prolonged period of time is that as you hold the muscle in a stretched position, the muscle spindle becomes accustomed to the new length and reduces signaling. Gradually, you can train your stretch receptors to allow greater lengthening of the muscles. Some sources suggest that with extensive training, the stretch reflex of certain muscles can be controlled so that there is little or no reflex contraction in response to a sudden stretch. While this type of control provides the opportunity for the greatest gains in flexibility to be made it also provides the greatest risk of injury if used improperly. Only consummate professional athletes and dancers at the top of their sport are believed to actually possess this level of muscular control. NEED TO COMPLETE AND CHECK FROM HERE ON How Does the Body Respond to Aerobic Training? The basis of aerobic Training -Prescreening The purpose of prescreening is to determine the current health status of the individual before starting physical activity. For individuals who are younger and in a healthy state, pre screening can be useful for comparisons further into the training cycle. Screening can also assist in identifying medical conditions and existing injuries that may be aggravated through training For people leading a sedentary lifestyle or having medical problems, screening can assist direction as to the amount and intensity of training to be undertaken without compromising the individual’s health. -Application of FITT Principle Frequency- how often we train, how many days a week. People looking to improve general aerobic level of fitness must be 3-4 times per, athletes up to 6-7 times per week and to loose weight needs to be every day. Intensity- how hard in terms of heart rate the athlete is working. 60-80% of max heart rate is within the training zone Time- how long we are exercising for, 20-30mins is good. Time to produce a training effect Type- sustained and of moderate intensity to improve cardio respiratory endurance. Activities should focus on large muscle groups such as arms and legs like swimming, cycling, jogging, rowing, shadow boxing. Immediate Physiological Response to Training FIND SYDNEY UNI SHEETS TO SUPPLEMENT THIS 1. Heart Rate: increases with exercise. Steady state is a period of time during which oxygen uptake remains at a uniform level such as swimming at a constant speed. An unfit person’s heart rate will keep increasing and not achieve a steady state. When exercising stops heart rate will decrease rapidly but the fitter you are the quicker you recover. 2. Stroke Volume: amount of blood ejected by the left ventricle during one contraction (mL/beat). Stroke volume increases during exercise, mostly when progressing from rest to moderate exercise. There is a large difference between a fit and an unfit person’s stroke volume. Stroke volume increases with training by up to 20% 3. Cardiac Output: amount of blood pumped by the heart in a minute, this increases with exercise. Cardiac Output= SV x HR. An athlete might have 100ml per beat and 60beats a min giving them a cardiac output of 6L per min. Untrained people can increase cardiac output from 20-22L per min during exercise. Trained athletes can increase up to 35-40 L per min achieved at a lower max heart rate and are able to perform more work at a higher intensity. 4. 5. Lactate Levels: this increases with intensity of exercise but is broken down in the presence of oxygen. The untrained person reaches the lactate threshold earlier and has less tolerance to increases in lactic acid levels Ventilation Rate: increases with exercise if working sub maximally it will plateau (level off) Physiological Adaptations in Response to Aerobic Training 1. 2. 3. 4. 5. 6. Resting Heart Rate: reduces with increased fitness as heart becomes stronger and more efficient. Normal 70, trained <40 beats per min. Stroke Volume: cardiac output and stroke volume can increase with training. Stroke volume for a trained athlete can increase up to 20%; cardiac output can increase up to 40L per min while exercising. Increases in cardiac output of a trained athlete are due to the huge increase in stroke volume. Oxygen Uptake (VO2 max, aerobic power): increases with training. Trained athletes =75ml/kg/min while untrained =35ml/kg/min therefore trained athletes can use more oxygen per kilogram of weight and therefore have a higher level of work capacity Lung Capacity: the amount of air that the lungs can hold 600ml for adult male Hemoglobin Level: Haemoglobin-the substance that binds to oxygen transports it around the body. Haemoglobin level increases allowing more O2 enriched blood from lungs to muscles. Training at high altitudes increases hemoglobin levels and endurance levels can increase by up to 20%. Blood Pressure: is the pressure that the blood exerts against the inner walls of the blood vessels. How can Psychology Affect Performance? Motivation- The drive towards the goal. It keeps us strivi9ng for success. It can be either 1. Positive: can be rewards, recognition or praise for good performance 2. Negative: feedback for unacceptable behavior causing athletes to avoid this behavior out of fear of consequences e.g. being dropped from a team Sources of Motivation 1. Intrinsic: comes from within, a feeling of satisfaction when achieving a goal and is important for continued interest 2. Extrinsic: are external such as rewards- trophy, money, and praise from the coach. Extrinsic motivation provides focus as well as rewards. Responsibility for motivation is shared between coach, athlete, media, peers, team members but sustained motivation relies on more internal factors than external. Athletes participate more as a result of internal motivation than other factors e.g. self satisfaction and also to be competent at a task (task orientation). Reinforcement: a form of reward or punishment/threat that influences the probability that an action or behavior will reoccur Social Reinforcement stems from coaches, players, peers and parents who influence the athletes. It arises from social contact and develops in an atmosphere of interaction, teamwork and cooperation. Different forms of reinforcement cause changes in behavior: Positive: someone the athlete admires or respects congratulating them Negative: Exclusion for poor performance and criticism Material: conferred in the form of tangible item’s such as badges and medallions (positive) or been fined, personal errors on match statistics sheet (negative) Internal: not visible like social or material reinforcement, often called covert or disguised reinforcement. Positive- a player can feel proud/sense of achievement which encourages repetition of behavior, can also be learnt through observation where an individual learns through someone else’s success and nurtures the experience to their own benefit Negative-not satisfied with personal achievement, not achieving to level hoped for. Anxiety This is a psychological process characterized by fear or apprehension in anticipation of confronting a situation perceived to be potentially threatening. It is a complex emotion identified by various levels of agitation. Arousal refers to the level of anxiety before and during a performance. The performance will be best when the level of arousal is optimal. Sources: Stepping outside comfort zone Break up of relationship Change in playing conditions Making a big decision that could affect others The non specific responses of the body to a demand placed on it. It can come from a number of places e.g. parents, media or from within e.g. how you cope with a certain situation/problem. It is characterized by: Increased blood supply to muscles Increased ventilation rate Increased glucose production, Increased sweat, production and Release of stimulant hormone adrenaline Tightened muscles to prepare the body for action can be internal (thinking and feeling) or external pressure (crowd or opponents) Athletes can use strategies such as: Mental imagery Relaxation Developing concentration by focusing on the immediate task rather than on the perceived reaction to it Developing confidence Planning strategies to cope with a situation State Anxiety State anxiety is more specific. It refers to a heightened presence of distress in response to a particular situation Trait Anxiety Trait Anxiety refers to a general level of stress that is characteristic of each individual. Trait anxiety varies according to how individuals have conditioned themselves to respond to and manage stress. Optimum arousal: Arousal equals the emotional, mental and physiological activation required to produce a response. It’s the drive, readiness, excitedness required for optimal performance. One theory is the ‘’ (inverted U) hypothesis which suggests there is an optimum level. However too little or too much leads to a decline in performance. Optimum level of arousal varies from skill to skill. In difficult tasks involving few muscle groups e.g. putting in golf or archery level of arousal need not be high to be optimum. Easier skills involving large body movements e.g. running or weight lifting need increased level of arousal for performance to be optimal. Managing Anxiety 1. Concentration/Attention Skills: Concentration is the ability to link movement and awareness to the extent that the individual can focus on doing rather than on thinking about doing. It is the ability to attend to appropriate stimuli in competition. E.g. a netballer focuses on the process of a shot one hand, bend knees, follow through etc rather on the players defending her, crowd, whether it is successful or not as these are known as irrelevant cues. 2. Mental Rehearsal The technique of mentally picturing the performance or skill before executing it and is also known as mental imagery. It is helpful to enhance competition performance but also the acquisition and building of motor skills. Used in weight lifting, gymnastics and high jump. Examples involve mental repetition in increase familiarity with desired motion. Effective in: Improving concentration and focus Narrowing thoughts to the task Elevates to desired level of arousal Increases confidence Increases motivation 3. Visualisation Involves all the skills in mental rehearsal: picturing a specific aspect of the performance ensuring the image is correct example-contact phase in a golf swing 4. Relaxation Series of techniques that seek to control the body’s response to stress/arousal. Techniques include: Mental imagery Progressive muscular relaxation Self hypnosis Meditation Centered breathing 5. Goal Setting These are the targets which we aspire to achieve. They can relate to either performance or behavior. Goals are: (SMART) Specific Measurable (quantify) Action oriented (performance/behavior goals) Realistic achievable and within athletes capability Timely within a certain time frame (short or long) How Can Nutrition Affect Performance? Balanced Diet A balanced diet needs: a balanced intake of nutrients to ensure the growth, repair, maintenance and functioning of tissues. Balance in terms of energy requirement to guarantee fuel demands matches energy intake Macronutrients: Protein Carbohydrates fat Are the major nutrients which supply energy and are essential for growth and development. Micronutrients Vitamins Minerals Water Are essential body nutrients but do not supply energy Carbohydrates Ideal fuel for activity Complex-cereals, wholegrain, fruit and vegetables Simple- cakes, sweets, biscuits Should be predominant energy source Muscle and liver glycogen is synthesized directly from carbohydrates Only source of fuel used during anaerobic Glycolosis (short, high intensity) Brain and nervous system rely on carbohydrates exclusively as they are unable to use either protein or fat Muscle glycogen stores take 24 hrs to restore Glycogen sparing-the metabolism of fat instead of carbohydrates during endurance work even though the body has sufficient energy stores of carbohydrates Glycogen-storage form of carbohydrates found in muscles and liver Fat Important for low intensity, long duration Becomes fuel supplier as glycogen reserves become depleted Dense in energy however needs more oxygen for metabolism and ensuing energy production. Results in increased respiration, increased body temperature and increased need for fluid Endurance athletes have no need for extra fat Unsaturated fats are best, found in vegetable and fish oil Excess fat, carbohydrates and protein is stored in fat cells Protein Important for structural role in holding the cells together and in growth as well as repair and maintenance of body tissue Used as energy source under extreme conditions Athletes need 1mg of protein for every kilogram of body weight Water Second to oxygen as an essential life providing element Body stores water both within the cells (intracellular) and outside the cells (extra cellular) Doesn’t provide energy Losses higher than 15% can be fatal Supplementation: the process used by athletes who cannot derive sufficient nutrient intake from their food consumption to meet their needs. This can be valuable where a genuine process like carbohydrate loading is used. However in many cases normal dietary intake is in fact sufficient and athletes using supplements are then taking in unnecessarily high amounts of certain nutrients. Vitamins and minerals: include a range of inorganic substances that enable normal body functions to be maintained. They are present on many foods, particularly in fruits and vegetables as well as meat. Among those most likely to require some supplementation are vegetarians (iron, protein), female endurance athletes (iron) and non dairy consumers (calcium). Where excessive amounts if vitamins and minerals are consumed through supplementation, the effects range from insignificant such as being excreted harmlessly through urine, through to more significant concerns such as muscle and joint pain, headaches and feelings of constant. Carbohydrate Loading: is a process that seeks to maximize the amount of glycogen stored in the muscles and liver, for use during aerobic performance. There are variations in the process for athletes to consider. Stage Timing 1 Days 1-3 2 Days 4-6 Competition Day 7 Purpose Glycogen depletion glycogen repletion Above normal levels Increased availability of stored glycogen for longer Strategies High intensity exercise low car intake Little or no exercise high carb intake higher intensities of exercise can be achieved and maintained Hydration Principles of body temperature regulation The ideal core temperature is app 37C which is maintained through the process of thermoregulation which is controlled by the hypothalamus. Thermoregulation ensures that a balance is maintained between heat loss and heat gain. Heat occurs through the normal metabolic processes and from muscular contractions. Heat loss occurs through: - Radiation: the loss of heat from the body to the cooler external environment via infra red rays - Evaporation: the loss of heat from the body when sweat is converted into vapor and leaves the skin - Convection: the transfer of heat through moving currents of air - Conduction: the transfer of heat through contact with other objects The process of Thermoregulation is assisted in its function by body responses such as - Vasodilation: where blood vessels expand to allow blood to circulate closer to the surface of the skin so it can be cooled and heat lost more easily - Vasoconstriction: where blood vessels become smaller to maintain blood flow closer to the warmth of the body core and vital organs - Involuntary muscle contractions: such as shivering to generate heat Controlling heat loss and heat gain is important. Heat gain is generally more common in physical activity due to muscular contractions however heat loss can be a factor in cold climates such as skiing and surfing. The presence of wind in an already cold area will drastically increase the risk of hypothermia. (Low=hypothermia). Acclimatisation may have a benefit here. Guidelines for Fluid Replacement Fluid replacement is essential in order to avoid debilitating effects on performance caused by dehydration and hyperthermia. Effective fluid replacement is achieved by increasing intake before, during and after performance. Before: at least 245 hrs prior to performance fluid intake should be increased. In 2 hours prior to performance, 500ml should be consumed app 200-300 should be consumed 15mins prior to game. During: small, frequent drinks should be consumed enough to replace the water lost through sweating. 200-300 ml every 15-20mins After: app 200-300ml for every 15-20 mins of exercise. The possibility of hyperthermia and dehydration is greater on hot and humid days. High humidity reduced the effectiveness of evaporation as a means of heat loss, as such fluid replacement needs are greater at these times. Water is recommended for consumption during sporting performances however sports drinks have been shown to be beneficial if they contain: - 4-8% carbohydrate can aid in absorption of water - 0.5-0.7 gm per litre sodium may help replace electrolytes lost during sport How does the acquisition of Skill Affect Performance? Training programs are essential to performance improvement. Effective programs focus on skill acquisition and development, together with physiological improvement but usually are supported by physiological strategies and by psychological strategies and nutritional plans. How skills are learned, tested and assessed is critical to performance improvement The learning Process Developing muscle memory is not a simple process, but it involves visualizing the movement, understanding the nature of the components, and then applying what is known. Learning to perform a physical skill such as throwing a softball requires the use of four important mechanisms; perceiving, deciding, acting and feedback. They occur in sequence-the end result being performance of the skill. While the skill can be performed without the need for feedback, it is most important in the refinement process which underpins skill improvement. Repetition of the skill in a cyclic process leads to the gradual improvement in the execution of the movement. Perceiving: often referred to as ‘input’, perception comes in the form of information called cues. Data arrives at the brain via the senses, mainly sight, sound and tough. Messages travel rapidly to the brain which transcribes the data into a visual blueprint. In this manner, the person develops the idea or perception of what needs to be done. In short, perception refers to the ability to conceptualise or see the important parts of a movement or strategy. Deciding: With the information stored in brain memory, the learner then decides how to use it. This is called processing. The brain interprets and codes the details so they can be used to work out how to convert the cues into an appropriate physical response Acting: once a decision has been made, the neuromuscular system (specifically the sensory and effector muscles) guides the person in making the desired movement. The action is called output. In this way the person executes a conceptualised plan in the form of a motor movement. Feedback: is the information provided to the learner about the nature or result of their performance. Characteristics of the Learner a) Heredity: Muscle fibre composition, somatre type (body shape), gender (males are stronger, less flexible etc), conceptual ability b) Confidence: Helps improvements in skills, success develops confidence c) Prior Experience: (transfer of learning) learning of similar skills accelerates learning of new skills e.g. basketball/netball, hockey/golf d) Ability: the way in which the individual is able to learn, process and implement new skills e) Personality e.g. consistency, reliability, level of motivation and ability to express feelings, positive learning attributes e.g. determination, the want to listen and learn The Learning Environment: refers to everything outside the learner and embraces the skill itself, the situation in which practiced, information from coaches and even the influence of the surrounding weather conditions. The environment can have a positive or negative impact on the learning experience. a) Physical Environment: this is external to the athlete e.g. crowd, weather, state of playing area, opposition and officials. When learning new skills the environment should be stable and as controlled as possible then developed into game like situations e.g. kicking a soccer ball then adding competitors b) Nature of Skill: Skills can be classified according to: I. Stability of the environment a. Open: take place in unpredictable circumstances such as surfing, tackle in rugby, goalkeeper save in hockey.–open or closed skill b. Closed: where circumstances are predictable and consistent such as a tee shot in golf, free throw in basketball II. The precisions of the movement a. Fine: movements that involve only small muscle groups such as finger releases in archery b. Gross: movements that involve large muscle groups such as swimming, running and throwing III. The distinctiveness of the beginning and the end of the skill a. Discreet: have clearly defined beginning and end and tend to be of short duration such as a golf shot or tennis serve b. Continuous: have no clear beginning or end and tend to be of an ongoing natures such as swimming, jogging or rowing c. Serial Skills: the combination of a number of smaller almost discrete skills into a whole skill such as gymnastics routine comprising round off, back handspring and back somersault performed consecutively IV. Timing- externally or self paced c) Practice Method: 1. Massed: long practice sessions broken up periodically by shorter periods. Suitable for highly motivated athletes. 2. Distributed: allows longer periods of time between shorter practice sessions. 3. Whole: involves the learner learning the skill as a complete movement. Some skills need to be taught as a whole but also useful for people who already have a high skill level or who learn skills quickly. 4. Part: involves learning a skill in different parts. It involves breaking the skill up into sub routines and learning each part individually before putting it all together as a whole. 5. Speed: attempts to learn skill at desired speed. Discus and shot put, some gymnastics are hard to learn slowly 6. Accuracy: focuses on performing the skill with completely accurate movements regardless of speed. With new skills should be taught and speed added later. d) Feedback 1. Internal 2. External 3. 4. 5. Concurrent (during) Delayed (after performance) Knowledge of Results: (feedback that provides information about the outcome of a movement.) Knowledge of Performance: (provides information about the patterns of movement in a performance). Can be concurrent or delayed, internal (kinesthetic sense) or external. Elite performers can use kinaesthetic sense to adjust movements appropriately so that the final result is unaffected. 6. Stages of Skill Acquisition Cognitive Stage: This is the first stage of learning. It is here where the athlete develops an understanding of the task. Demonstrations, videos are very important however coaches should be careful to avoid information overload. During this stage hopefully the learner will experience some success however frequent large errors do occur. - Focus on what to do Frequent large errors Learner is often unable to recognise errors Learner needs to see, feel and experience the movement An exploratory stage Demonstration is the best means of communication - Learners must identify subroutines Slow learning speed and inefficient movement Support fro teaching aids are required to enhance visualization of the skill. The teaching focus is on conceptualisation Associative Stage: This stage is commonly referred to as the practice stage. In this stage emphasis is on practice and the correct sequencing of movement skills. Skills become more refined and fewer errors are made. Kinaesthetic sense starts to be developed (feel of the movement) in this stage. - Identified as the intermediate or practice stage of learning Focus on how to do the skill Some errors but not so large Learner needs to practice Kinaesthetic sense is improved through practice Demonstrations are important - - Emphasis is on temporal patterning. The player will know the subroutines and is competent in assembling them into the required skill Moderate speed and reasonably efficient movement - Further improvement requires practice of set patterns of movements in controlled situations - Some athletes never progress past this stage. Autonomous Stage: Movement and skills are produced automatically. Athlete’s performance is consistent and has few errors. Athletes are able to focus on tactics, strategies and reading the game. They can detect and correct errors and have well developed kinaesthetic sense. Visualization is more effective for autonomous athletes. - Identified as the advanced - Demonstrations are only stage at which skills are essential to refine particular performed reflexively movements - Focus on other tasks - Temporal and sequential - Few errors patterning subroutines is - Performer is able to detect automatic and correct as they occur - Speed and efficiency that - Performer needs to adapt to relate to the specific the movement to pressure requirement of the situations situations - Improvement requires - Movements rehearsed under manipulation of the varying conditions environment to ensure the skill is able to be reproduced under varying condition ,Rates of Skill Acquisition Learning Curves and Plateaus Implications of rate of learning People learn at different rates and they will ultimately attain varying standards. By placing results on a graph, learning rates can be more easily seen and conclusions drawn about relevant factors. Factors that will impact on the rate of learning: - Nature of the task - Characteristics of the learner - The quality of instruction given - Practice opportunities - The merit of the feedback received and its capacity to be used effectively by the learner It is often assumed that the people who learn skills quickly, or those who display a high level of performance earlier, will reach the autonomous stage quicker or ultimately achieve much higher levels of performance. This can be true in many cases but not always. Some of the factors listed above may impact on the rate of learning but not necessarily on the level ultimately achieved. Additionally it is possible that early good performances may be achieved with a technique that will ultimately have limitations. The learner who makes the effort to perform the movement correctly, despite early difficulties may benefit in the long run. Skilled Performers versus Unskilled a) Kinaesthetic Sense: an awareness of muscular effort and body positioning during movement. Inexperienced performers make mistakes because their muscle memory is not fully developed. Highly skilled performers are alert to movement error and are able to make correction while executing the movement b) Anticipation and Timing: The capacity to accurately predict what is likely to occur and then respond appropriately in the required time. Skilled performers are better able to predict what may happen in specific situations and also leads to better timing of responses. Anticipation is important in externally paced sports such as cricket, baseball and squash, timing firstly applies to skill acquisition. If not timed well, execution appears jerky and uncontrolled. God timing allows athletes to concentrate on other performance aspects such as their opponent and when to hit the ball. Timing secondly applies to the performer being in the right place at the right time or being in the optimum position for skill execution. c) Mental Approach: Refers to an athlete’s state of mind being conducive to achieving peak performance. Skilled performers can: - Recognise and respond to only relevant cues called selective attention where they block out irrelevant aspects of the situation. - Respond to multiple cues such as changes in the environment and attend to tactics simultaneously - Realise the importance of optimal arousal and us well developed techniques for its generation and control - Establish goals and feel a desire to achieve them Use benefits of experience to advantage d) Consistency: the capacity to perform at a high standard on a regular basis Objective Measurement of Skill a) Skill Related tests: Measurement is a process of using numeric information to assess and compare skills and performances e.g. times and distances. The greater the accuracy of the tests, the more reliable the data and the higher degree of objectivity. Where measurement is not part of the assessment of performance it tends to be subjective and less accurate. Subjective refers to a judgment of performance based on feelings, impressions or opinions rather than a measurement system. Objectivity is the extent to which a measure or test is independent of the observer. Objectivity runs on a continuum from highly objective to slightly objective. High jump or javelin are highly objective while judo and fencing require interpretation of special rules. Observations can be made more objective by using - Check lists: style, technical correctness, execution - Measurement systems: instruments take times, tapes - Established Judging Criteria: a set of procedures, rules or guidelines - Rating Scales: degree of difficulty, marks for technique - Using judges with no personal or competitive affiliations with any competitors - Disregarding the highest and lowest scores for each performance from the judging panel and averaging the rest of the scores b) Validity and Reliability of Tests: When measuring a skill it is essential it is both valid and reliable. Validity ensures the relevance of the information being received from the test, while reliability ensures that the results are accurate or consistent with what the performer actually achieved. A good example is the vertical jump test. When the vertical jump test is used to measure leg power it is a valid test. When the person administering the test correctly follows the protocol it is a reliable test. Validity: is the honesty of a test i.e. the degree to which it measures what it is supposed to measure Reliability: the degree of consistency of a test i.e. the ability to measure the same attributes of the same individual or group under the same conditions. Judging the Quality of Performance a) Characteristics of a skilled performance - Anticipate responses and react to them quickly - Coordinate movements, giving the impression of fluency - Control of movement - Focus on tactics and strategies rather than on how skills are performed - Gain the desired outcome from demonstrated movements - Reveal resourcefulness in having a range of options in any particular movement - Executes skill with ease, using speed and efficiency b) Outcomes of a skilled performance - Financial remuneration such as sponsorship - Increased motivation and desire to improve - Transfer of learning to other sports or skills - Able to analyse and critically evaluate your performance and other peoples performances, extra responsibility - Self confidence and esteem improved - Improved standards of performance - Increased media profile - Increased extrinsic rewards - Restricted lifestyle or behavior because of potential impact on performance - Increased pressure (stress) to repeat or exceed current levels of performance - Personal satisfaction and enjoyment - Derive respect from others c) Personal versus prescribed judging criteria - Personal Criteria: are the preconceived ideas or expectations that an individual brings to judge performance - Prescribed Criteria: are the established by a sports organisation or body, and form the basis of assessment for competitions in that sport or activity.