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Factors Affecting Performance

Factors Affecting Performance

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Factors Affecting Performance

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  1. Factors Affecting Performance HSC Core 2 Focus Question: How can nutrition and recovery strategies affect performance?

  2. While athletes are encouraged to follow the basic principles of healthy eating (including following the Dietary Guidelines for Australians and the Australian Guide to Healthy Eating ) there is, a need for athletes to increase their overall kilojoule intake to compensate for the additional amount of energy used in training and performance. The increase in the amount of energy required varies according to the activity being undertaken. By understanding the dietary needs of athletes and planning eating strategies for before, during and after activity, individuals can enhance their recovery and maximise physiological responses from training, and in turn, improve their performance. Athletes also need to be conscious of their fluid intake and consider the place of supplementation and recovery strategies in their training programs. (For Activity)

  3. Nutritional considerations An athlete must ensure that their diet is adequate enough to meet performance needs. Different sporting activities require different levels of energy and nutritional needs. Programs designed to improve performance must be supported by sound nutritional practices. If nutrition is not included as an integral part of training and preparation for competition, even the most talented athlete may never reach their full potential. While complete nutritional balance is essential for optimal physical performance, the specific roles of carbohydrates and hydration are the two most important considerations. Athletes need to consider factors such as what to eat and drink, the most appropriate time for food intake and strategies to recoup expended energy as well as training and performance requirements.

  4. Pre-performance nutrition is about preparing the body for exercise. There are a number of important considerations for athletes to be aware of as part of pre-performance nutritional strategies. These include: what type of food to eat and in what amount when to eat and drink and how to carbohydrate load if required. Food consumed prior to activity is useful only if fully digested and its energy and nutrients available to where they are required in the body. Fluid levels rarely keep pace with the body's requirements, and they need to be repeatedly replaced. Pre performance (For Activity)

  5. Type of food As carbohydrate is the primary fuel source for exercise of moderate to high intensity, optimising carbohydrate levels in the muscle and liver is the primary goal of pre-performance preparation. Foods higher in fat and protein and fibre require longer periods to digest than most foods. This may lead to discomfort and possible indigestion if consumed close to activity or in large amounts. Liquid meals (drinks with high carbohydrate content) are sometimes recommended for athletes. Athletes are advised to eat mostly complex carbohydrates, such as wholegrain cereals, such as bread, pasta and rice, because they have a low glycaemic index (GI) , that is, provide slow energy release. Amount of food Generally, the appropriate amount of food relates to the expected energy expenditure of the event. This will vary with the type of activity and level of competition, e.g. competitors in endurance events need more energy over a period of time than events requiring short sharp bursts of anaerobic energy. Care needs to be taken that large amounts of food are not eaten prior to any event as it may cause gastrointestinal discomfort, particularly if the activity is of high intensity. When to eat Most athletes feel comfortable having a meal 3 to 4 hours prior to competition. If the time period before the event (or between games/events) is shorter, food intake should be in the form of snacks and liquid preparations.

  6. Hydration Hydration is important for all individuals, however for athletes, and especially those involved in endurance events or competing in hot or humid conditions, it is of extreme importance. As a general rule, 500-600 mL of fluid should be consumed in the 2 to 3 hour period prior to endurance performance and 250-350 mL in the last 15 minutes. Athletes competing in endurance events or those that last longer than an hour may benefit from including sports drinks in their pre-performance preparation. The weather conditions on the day need to be considered carefully when planning fluid intake. High levels of humidity can extract a significant toll on athletic performance. Carbohydrate loading There has been much debate about the effectiveness of carbohydrate loading. Theoretically it aims to maximise glycogen stores prior to performance therefore gaining a competitive edge. Carbohydrate is the preferred source of energy for the body therefore athletes increase the amount of carbohydrate they consume leading up to an event in the aim of maximising the body's storage of glycogen. The higher the levels of muscle glycogen, the greater the endurance of the muscles during performance. The process of carbohydrate loading has been modified in recent years. New techniques involve consuming a diet high in carbohydrates and tapering training for two to four days before competition, causing glycogen supplies to be at maximal levels. It is also believed that athletes involved in short-term, low-intensity activities do not need to carbohydrate load as a normal diet should provide adequate amounts of glycogen.

  7. During performance nutrition needs to be focused on maintaining energy levels. Endurance events and events in hot and humid conditions can have a significant impact on the body's fuel and fluid supplies. The need for carbohydrate and electrolyte replacement depends on a number of factors including intensity, duration, humidity, and individual sweat rates. In the case of moderate to high-intensity activities lasting longer than 60 minutes (including individual or team-based sports of an intermittent nature) additional fuel in the form of carbohydrate supplementation is needed to avoid glycogen depletion. Appropriate liquid carbohydrate supplements (e.g. some sports drinks) can delay glycogen depletion by up to 30 minutes at exercise intensities above 75% of aerobic capacity. Liquid carbohydrate is not necessary for low intensity, short-duration exercise. Sports gels and bars are being used more increasingly by athletes as these are easy to consume and digest quickly providing a quick release of energy for the athlete as well as reduce the risk of gastrointestinal problems. Care should be taken that these products are well researched and used appropriately. Adequate hydration by regular fluid intake must be maintained and needs to the body's requirements and the exercise duration and intensity. 200-300 mL of fluid is recommended to be consumes every 15-20 minutes during exercise. An athlete should not use thirst as an indicator of dehydration as hydration levels may be well depleted by that time and performance may already be affected. Dehydration of even 2% can have a detrimental effect on an athlete's performance during performance (For Activity)

  8. Post-performance Post-performance nutrition should focus on replacing energy stores as quickly as possible. This is best achieved through proactive recovery enabling optimisation of body repair and regeneration processes. Post-performance nutrition involves replacing energy stores following exercise as quickly as possible. How well athletes recover after a session of exercise will have an impact on their ability to perform in future training and competition. A post-performance nutritional plan aims at returning the body to its pre-event state as soon as possible. This is best achieved through proactive recovery, i.e. active recovery rather than prolonged rest. This means that refuelling (carbohydrate) and rehydration (fluid and electrolytes) should begin immediately (ideally, within 30 minutes) and continue for 8-12 hours following the performance. This enables optimisation of body repair and regeneration processes. The best way to recover is to act quickly and eat food with high carbohydrate content. An intake of foods with a high glycaemic index (GI) is most beneficial as it raises blood glucose levels faster than low GI foods. Rehydration should involve an increased level of electrolyte and carbohydrate than previously prescribed (during activity) as well as an increased quantity. Dietary protein consumed immediately after a session is taken up more effectively by the muscle for rebuilding processes (as exercise can cause a substantial breakdown of muscle tissue) than is protein consumed hours afterwards. Active rest (light exercise such as walking and stretching) enhances recovery of body systems damaged by the stress of the activity. It can be difficult for athletes who take part in multiple training sessions each day or who train for extended periods of time to replace fuel and fluid stores adequately. Extensive, strict planning is required.

  9. Many athletes and coaches believe that a balanced diet alone is not enough for optimal performance. If an athlete uses extra food substances in their diet it is referred to as diet supplementation. There are many types of supplements available to athletes and they vary greatly in terms of their impact on performance. Supplements can assist athletes to achieve peak performance. However, poor regulation of the supplement industry allows athletes to be bombarded with marketing hype that exaggerates or completely invents unproven benefits arising from the use of supplements. Unfortunately, the driving force behind the supplement practices of many athletes is not sound science applied to the specific needs of a sport. Instead, some athletes are motivated by fear that their competitors might be taking supplements and that they can't afford to miss out on any 'performance edge'. The results of the present frenzy of supplements in sport are: a small but real risk of a positive 'doping' outcome money being wasted on products that simply do not work time, money and belief being distracted away from the factors that can really enhance health, recovery and performance Supplementation (For Activity)

  10. Supplementation Dietary supplements can take many forms, including vitamins, minerals, protein, caffeine and creatine products. Supplement intake is routine for many athletes. However, supplements may be of little value if the diet is already well balanced in terms of nutritional requirements. Athletes use nutritional supplements for many reasons, including their belief that: • supplements enhance their performance • their nutritional needs are not being met due to their increased training loads • they eat poorly or have an unhealthy lifestyle • the claims of advertising (of the products) are true. Supplementation should not replace a well balanced appropriate eating plan. It can be beneficial in circumstances where there are special needs resulting from ill health, poor access to quality food or body deficiencies. The following links will explore supplements in further detail.

  11. Vitamins & minerals The body is unable to manufacture vitamins, so diet must supply them as vitamins are essential to maintain bodily functions. Excessive quantities of some vitamins can be unnecessary, expensive and potentially dangerous. Vitamins and minerals are micronutrients, meaning that they are only needed in very small amounts in the body. They do not contain energy but perform vital roles in the body such as growth and metabolism. The body is unable to manufacture vitamins and as such diet is the key source of vitamins and minerals. Some athletes consume vitamin supplements, such as a multivitamin, as a type of 'nutrition insurance', even though their diet may be very good. This can be an expensive option, with no proven benefit and may have potential for danger, as an excess of some vitamins can cause health complications and/or have a detrimental effect on performance. Fruits and vegetables are strongly recommended as ideal sources for many vitamins, especially if a variety of different colours are consumed.

  12. Minerals are micronutrients that are essential for the body to function properly. Iron and calcium are the two most common minerals deficient in athletes, and inadequate supplies will diminish performance and contribute to health problems. Iron and calcium are essential minerals for body function and the two minerals that are most commonly deficient in athletes, affecting performance as well as health. Iron is found in haemoglobin (in red blood cells) which collects and transports oxygen to where it is needed in the body. Low iron levels therefore affect performance as muscles are deprived of oxygen. A balanced diet will supply adequate levels of iron through foods such as lean meats, grainy products, and leafy green vegetables. People who are most at risk of iron deficiency are endurance athletes, females, vegetarians and adolescent males. Calcium deficiency is more specific to health as it is vital for bone structure. The quality of bone tissue deteriorates gradually from the age of about the mid-twenties, and this contributes to brittle bones (osteoporosis). For older athletes, especially females, this is extremely important as sport can put a considerable amount of stress on the body, particularly the muscles and bones. Sources of calcium include dairy products, leafy green vegetables and fish such as salmon and sardines.

  13. Protein As protein is responsible for the growth, repair and maintenance of body tissue the use of protein supplements is common amongst power and strength athletes such as weight-lifters, rugby league and rugby union players. Research has shown that most athletes do not need or benefit from protein supplementation. Protein supplements have had a strong favour with weight-lifters, body builders and strength athletes for a long time as protein in the form of amino acids is the basic structure of muscle. Protein supplements can be natural or synthetic and are available in powder, liquid or solid formulations. Many athletes believe that protein supplements are important because of their muscle building qualities, with higher intake positively affecting muscle size, when in fact, this is a misconception. The body can only utilise a small amount of protein at any one given time, therefore excess protein will not aid in tissue growth and is often wasted. Protein can be used as a source of energy when carbohydrate and fat stores are in short supply or are exhausted. Most well balanced diets (made up of fish, chicken, red meat, milk and cheese, wholemeal/grain breads and cereals, and some types of beans) contain ample protein. High amounts of protein can negatively affect health. High amounts of protein can increase the amount of calcium excreted in the urine and possibly contribute to osteoporosis. Excess protein is eliminated by the body and this processing and filtration can interfere with kidney function. Diets high in protein can often have a high fat content, contributing to weight gain and blood vessel blockage. Typically an increase in protein in the diet may be at the expense of other nutritious foods such as fruit and vegetables, which may then lead to deficiencies in some nutrients.

  14. Caffeine • Caffeine is a central nervous system stimulant. While much of the evidence relating to caffeine and performance is still inconclusive, there is general agreement on areas relating to cognitive function, anaerobic performance and aerobic performance. • Caffeine is most commonly found in coffee, tea, cola drinks, energy drinks and chocolate and as such is present in many people's diets. Caffeine is a stimulant and can affect the body in as little as 30 minutes. The majority of the caffeine's ergogenic effects are seen after 45-60 minutes when blood levels of caffeine peak. These include: • increased heart rate and disrupted heart rhythm • symptoms of anxiety (in high doses) • improve cognitive processes, such as alertness • decrease athlete's rating of perceived exertion - making athletes feel as though they are performing more easily than they actually are • relax smooth muscles (such as intestines/bowels).

  15. The most favourable evidence supporting ergogenic aid properties of caffeine relate to endurance sports such as marathon running. Increased caffeine levels can make some athletes feel 'jittery and unsettled' before competition so athletes need to be aware of individual variation in the benefits of caffeine. It can also affect sleep quality and quantity which may adversely affect recovery. In the past, consumptions of large amounts of caffeine was considered illegal in international sport and banned under the World Anti-Doping Agency (WADA) code. Caffeine has recently been removed from the WADA banned list with evidence showing that high doses of caffeine don't produce performance enhancement and generally result in adverse side effects. The diuretic effect of caffeine has been a contentious issue however for most athletes the link with dehydration is not supported. Although caffeine is a mild diuretic it does not exacerbate dehydration. Athletes performing in hot or humid conditions on the other hand may need to re-evaluate their caffeine intake.

  16. Creatine products Creatine is important in energy production as it contributes to the resynthesis of ATP in the first 10 seconds of performance. Advocates of creatine use believe it enables athletes to train more effectively in power sports. It is important in making energy available to sustain short duration explosive activity as in weight-lifting and sprinting. Creatine is occurs naturally in the body's muscle tissue. It can also be found in the diet, with the main source being from meat. In the muscle, creatine is converted to creatine phosphate which provides a ready source of energy to resynthesise ATP for working muscles during high-intensity anaerobic activity such as weight lifting and sprinting. Because creatine cannot be stored in the body, athletes attempt to increase the body's stores of creatine by supplementation. By supplementing creatine, athletes are trying to enhance the efficiency of the ATP-PC system to provide energy and resynthesise ATP faster. While manufacturers of creatine products continue to market its performance enhancing properties, including increasing strength, delaying fatigue and burning fat, research is still inconclusive and little may be gained from consumption. Creatine supplementation has been associated with increases in weight (due to water retention), hence many athletes avoid it. Creatine is however, used by many strength athletes, as research has established that muscle hypertrophy (growth) is more easily achieved when training is assisted by creatine supplementation. Vegetarians may benefit from creatine supplementation as their diets lack protein, which is a main source of creatine. However, this is only of benefit to athletes taking part in explosive anaerobic activity, not endurance activities. .

  17. Recovery is the re-establishment of the initial state. It can be passive or active and requires planning. Recovery is an integral aspect of training. It focuses on identifying strategies that athletes can use to minimise and manage fatigue from training and competition. Appropriate recovery strategies will: maximise gains from training and improve quality in every session improve consistency of quality performance minimise and eliminate injuries, overtraining, illness or burnout. (Board of Studies. PDHPE Stage 6 Support Document. 2010.) Elite athletes use a range of strategies designed to enable them to minimise fatigue associated with high-volume training and resume full training in the shortest possible time. Recovery strategies can be categorised as physiological, neural, tissue damage or psychological. If recovery is inadequate the athlete may be: incapable of performing at the expected standard prone to injury susceptible to overtraining or non-functional overreaching . Recovery strategies (For Activity)

  18. Physiological strategies Physiological recovery strategies aim to remove the metabolic by-products of exercise through a cool down period as well as replace lost fluids and energy. Physiological strategies aim to remove metabolic by-products and replace lost fluids and energy stores. Cool down The cool down, or active recovery, is a group of lower intensity exercises performed immediately after exercise to remove waste products, decrease muscle soreness, improve muscular relaxation, bring the cardiovascular system back to rest and allow time to reflect on the training or performance. This could involve short jogging repetitions, slow swimming or similar low intensity activity. Static stretching is often combined with the cool down to improve range of movement and reduce the risk of injury. Hydration Thirst is not an accurate predictor of dehydration. An organised schedule of fluid replacement is required to fully hydrate athletes after performance. Studies have shown that athletes typically replace only about 50% of their sweat loss and often undertake subsequent sessions in a dehydrated state, reducing their performance ability. Alcohol can increase swelling to damaged tissue and increase fluid loss. It should be avoided for at least 24 hours after exercise to allow full recovery.

  19. To replenish fluid lost during training or games the athlete should consume approximately one litre of water for every kilogram of body weight lost. The addition of carbohydrates will speed up fluid replacement as well as refuelling muscle glycogen stores. The foods eaten in the 30 minutes immediately after exercise should be medium to high glycaemic. Sports drinks are useful because they provide fuel and fluid but should be limited to the 30 minute period following exercise. Solid foods, such as fruit, should be encouraged as they provide additional nutritional value. Compression garments Compression garments can assist the removal of waste products from the muscles as well as provide the muscles with oxygen and nutrient-rich blood by stimulating circulation. Compression garments assist athletes to recover faster and with less negative post-exercise effects such as muscle soreness and lethargy.

  20. Neural recovery strategies such as hydrotherapy and massage help replenish the nervous system. The change in chemicals found in muscles following heavy bouts of exercise or psychological stress can be addressed by these neural strategies. Hydrotherapy and massage aim to relax muscles that have been fatigued or damaged as a result of high intensity exercise. Neural strategies, integrated with other recovery strategies, have become popular in recent years, particularly with teams involved in contact sports such as rugby league. Hydrotherapy Hydrotherapy involves the use of water to relax, soothe pain and assist metabolic recovery whilst providing support for movements which eliminate jarring and straining movements. Typical hydrotherapy methods include spas, underwater massage and swimming pools (heated and non-heated). Active exercise can be incorporated into hydrotherapy sessions allowing a gravity assisted environment. Many forms of equipment have been designed to assist movements. Water therapies are not used or valued as much in Australia as they are in European countries, where a wide range of therapies have been in use for several thousand years. Sports teams such as rugby league, rugby union and AFL have recently been seen undertaking hydrotherapy sessions as part of their post-game recovery strategies. Neural strategies

  21. Two common strategies used in hydrotherapy include: Contrast water immersion: Alternating hot water (39-40°C) spa sessions (approx 3-4 minutes) with cold water (10-15°C) plunge repeated three times. This aims at enhancing recovery by increasing blood flow through the actions of vasoconstriction and vasodilation (narrowing and widening of the blood vessels). It improves waste removal and nutrient delivery and often results in the athlete feeling refreshed and alert. Click on the following link for a deeper understanding of contrast baths. Even temperature immersion: Promptly following a training session, game, or competition, the athlete showers or bathes, often with hot water. This accelerates recovery of lactates and reduces metabolic fatigue. Interspersing stretches with light active movements in a pool appears to reduce post-performance stiffness and accelerate the return to a normal state. Spa baths are often used allowing a massage effect from the jets.

  22. Massage The main purpose of massage is to assist in reducing training fatigue. It can also be helpful in a preventative way in reducing localised muscle tension that can with time lead to overuse injury. The physiological impacts of massage on the recovery process have still to be fully researched and understood. There is evidence of massage leading to improved mood states and feelings of well being that help physical and psychological relaxation. Some of the claimed benefits include: • waste removal and increased food/oxygen supply leading to faster recovery and earlier return to training • minimising the effects of fatigue • inducing calm and mental relaxation and encouraging effective sleep • reducing muscle tension • temporary flexibility gains • breaking down adhesions to increase muscle elasticity and reduce risk of further injury • realignment of collagen fibres after injury, leading to flexible, stronger scar tissue. Sports massages are a specialised form of massage, focusing on reducing tension in the muscles caused by exercise, relieving discomfort and soreness or for injury treatment. Therefore the treatment should specifically suit the needs of the athletes and demands of the sport or activity.

  23. Tissue damage recovery strategies aim to minimise the level of tissue damage and promote healing. Strenuous activity causes minor muscle fibre tears and the body's response is to repair this damage. Cryotherapy (cold therapy) assists in offsetting this tissue damage. Cryotherapy, or cold therapy, is the local or general use of low temperatures to remove heat from a body part. The goal of cryotherapy is to decrease pain and inflammation, promote vasoconstriction and prevent the build up of waste products. Various forms of cryotherapy have become popular as recovery strategies for many athletes. Ice pack therapy is a treatment of cold temperatures to an injured area of the body. An ice pack is placed over the injured area and absorbs heat, decreasing metabolism and oxygen demand. There is immediate vasoconstriction, followed by vasodilation. Tissue damage strategies

  24. Psychological strategies Psychological recovery strategies aim to disengage the athlete from the performance. Heart rate, breathing and body temperature remain elevated post exercise and may take time to drop as do anxiety levels about the performance or future performances. Strategies such as relaxation assist to bring these levels to normal levels. Following intense training and demanding performances, athletes may experience symptoms of low concentration, lack of motivation and increased levels of anxiety. Psychological strategies can play an important part in emotional and possibly spiritual recovery by assisting in recovery of concentration, lifting motivation and decreasing anxiety levels. Two psychological strategies that can be used to enhance recovery are outlined below. • Relaxation skills - These can reduce levels of tension and arousal and also energise the athlete. Individuals relax in many different ways, with some preferring to read a book, listen to music or watch television. Specialised relaxation techniques are also widely used, including meditation, progressive muscle relaxation, visualisation, breathing exercises, positive self-talk and flotation. The athlete needs to practice only one or two techniques on a regular basis for these to become effective tools to use to aid recovery. The choice of relaxation methods is quite individual and involves experimentation to establish which technique works best. • Rest and sleep - Rest days are essential and a least one day per week should be a non-training day. This allows time for physical and psychological recovery as well as time for other interests and activities. Adequate sleep (7-9 hours) is regarded as probably the most important recovery strategy as it provides regeneration and restoration of the body's systems to allow adaptation to training. Too much sleep however, can be detrimental, contributing to sluggishness and lethargy.

  25. First 5 minutes – refuel and hydrate – sports drink and high GI carbohydrates. Next 15 – 20 minutes – cool down including slow movements and stretching – continue to hydrate. Followed by 20 minutes of hydrotherapy such as cold baths – continue to hydrate. Within the first hour – complete a debriefing of the game and start to unwind, relax. Later that day – continue to hydrate, refuel and relax to come down from the arousal levels of the game – avoid alcohol. Good nights sleep. Next day hydrotherapy and light exercise. Post match recovery plan