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Gross Motor Skills Skills that involve the movement of large body parts or the whole body Cardiac output Vasoconstriction The volume of blood pumped by the left ventricle in one minute Narrowing of the blood vessels Thermoregulation The ability of an organism to keep its body temperature within certain boundaries Vascular Shunting The process of directing blood to where it is most needed Hypoxia A shortage of oxygen in the body Vasodilatation Widening of the blood vessels Stroke Volume The volume of blood pumped by the left ventricle in one contraction Venous return Ventilation Rate The flow of blood back to the right atrium of the heart Sympathetic nervous system The link between the cardiac acceleratory system and the heart that results in an increase in heart rate The rate at which gas enters or leaves the lung Hydrated Combined chemically with water Tachycardia Abnormally rapid heartbeat (over 100 beats per minute) Osmolality A measure of the number of particles in a solution. Hyperthermia Hypothermia A condition in which the body temperature drops below that required for normal metabolism and bodily functions An acute condition that occurs when the body produces or absorbs more heat than it can dissipate Stage 1: Initial Preparation • Gross Motor Skills and Pulse Raiser Why? • Introduce stress in a gradual and controlled manner • Prepare the body physiologically and psychologically for performance • Raise core body temperature • Improve performance • Raise Muscle temperature • Reduce the risk of injury • Achieved by some for of cardiovascular exercise Stage 2: Injury Prevention • mobility exercises • Increase localised muscle elasticity • Stretches Stage 3: Skill Practise • Involves skill related component • Neuromuscular mechanisms for the activity are worked • Example shooting in netball Stage 4: Sport-Specific • Often combined with Skill Practise • Practise specific skills and exertions similarly to how they will be experienced in match situations Increase in heart rate which leads to vasodilatation of some blood vessels Increase in cardiac output which leads to vascular shunting Increase in stroke volume which leads to vasoconstriction of some blood vessels Increase in venous return which causes thermoregulation to begin Increase in the speed of nerve impulses Increase in localised and core heat generation which causes localised muscular metabolism to speed up Increase in muscle elasticity Ventilation rate increases which causes dilation of capillaries Production of lactic acid, synovial fluid and adrenaline Carbon Dioxide build up Used to increase the elasticity of muscle and connective tissue to reduce the risk of injury. Static Stretching • lack of movement Dynamic Stretching • Stretch a muscle and hold position for up to 30 seconds, relax and repeat • Controlled movements taking the joint through its full range of movement • least sports specific • More sports specific than static • Muscle joint must be warm • Controlled leg swings Passive Stretching • Assume position and hold it with some other part of your body, with a partner or apparatus • E.g. partner lifts extended leg and holds it in place Ballistic Stretching • Like dynamic but uses bouncing or momentum to help forcibly stretch the muscle • Bouncing action means increasing the risk of injury & increasing potential for Delayed-onset muscle soreness • Unlikely to allow muscles to adjust to and relax in the stretch position. Could cause them to tighten up Proprioceptive Neuromuscular facilitation (PNF) • Advanced form of flexibility training • Involves passive stretching followed by isometric contractions of muscle group being targeted • Very sports specific Active Stretching • You actively stretch the muscle yourself • E.g. sit with legs outstretched and move body towards your legs yourself Adenosine Phosphate Phosphate Phosphate 2-3 Seconds •ADP • Phosphate ATPase Creatine Kinase Phospho creatine Energy Energy 8-10 Seconds Phospho Phosphate creatine ADP Energy ATP ATP= Exothermic reaction PC= Endothermic Reaction Coupled Reaction Controlling Enzymes • ATPase breaks up the ATP to form ADP, Phosphate and Energy • Phosphocreatine is broken down by Creatine Kinase which produces energy. This energy is then used to reform an ATP molecule by binding ADP with a phosphate • ATPase • Phosphocreatine Practical Application • Shot Putt • Shooting in netball ANAEROBIC Recovery Process • Lactic Acid System • 100m for an elite athlete By Products & effects • Creatine but has no effects and will eventually rejoin Phosphate to form phosphocreatine again Occurs in the sarcoplasm of the muscle One Glucose Molecule Can last for 2-3 minutes PFK Energy Lactate dehydrogenase Two molecules of lactic acid LDH Two molecules of pyruvic acid 2ATP Type of Reaction Reaction Site • Exothermic Chemical/ Food Fuel •Anaerobic Reaction • Glucose • Sarcoplasm of the muscle Practical Application Recovery Process ANAEROBIC • Aerobic System • Active cool down • 800m • Following or defending a player on the ball in football Because it is not at full intensity and will last longer than 15 seconds By products and their effects • Lactic acid which can cause cramps which will then cause the athlete to stop competing Medium Intensity Controlling Enzymes • PFK which turns glucose into pyruvic acid • LDH which turns pyruvic acid into lactic acid 2ATP Aerobic Glycolysis: PFK Glycogen Glucose Pyruvic Acid Krebs Cycle: Pyruvic Acid Coenzyme A Acetyl CoA Citric Acid Oxalocetic Acid Various Chemical Reactions = Carbon Dioxide, Hydrogen and 2ATP Electron Transport Chain Water Hydrogen NAD FAD 34 ATP After about 3 minutes Type of Reaction • Aerobic Reaction Total of 36 ATP Reaction Site • Sarcoplasm of muscle Chemical/ Food Fuel • Mitochondria Low Intensity but High to very high duration • Glucose Practical Application • Marathon • Football to last the full duration of the match By Products and their effects • Carbon Dioxide which increases the athletes respiration rate • Water which induces sweating and increases urine output Recovery Process • Active Cool Down • Stop Exercise Controlling Enzymes • PFK • CoenzymeA • NAD • FAD Energy Source Main Functions Used as energy fuel when: Carbohydra tes High intensity energy Intensity of exercise is at a level that cannot be sustained through metabolism of fats in the aerobic system Fats Low intensity fuel Insulation Intensity of exercise is at a medium to low level and energy requirements can be met through metabolism of fats in the aerobic energy system Proteins Muscle tissue growth Muscle tissue repair Energy The athlete has eaten very low carbohydrate diet or is experiencing a famine or towards the end of an ultradistance event • Glucose is the basic usable form of carbohydrate in the body. • Can be used directly by the cell for energy, stored as glycogen in the muscle and liver or converted to fat • The function of the liver is to convert glycogen into glucose when it is needed for energy production Anaerobic: 55-60% Aerobic: 60-70% Monosaccharides Glucose, Fructose and galactose Fruit Disaccharides Sucrose and maltose Sweets Polysaccharides Glycogen and starch Bread Fats are present in the body mainly as triglycerides, fatty acids and cholesterol Saturated Fats • Has its carbon atoms saturated with hydrogen atoms • Consumption of large amounts can lead to high blood cholesterol levels and coronary heart disease. • Obtained from animal fats such as pork, beef and lamb Unsaturated Fats Anaerobic: 10-20% Aerobic: 20-30% • Does not have their carbon atoms saturated with hydrogen atoms • Liquid state at room temperature • Found in vegetable oils Cereal, Cheese, eggs, fish, lean meat and liver • The basic structural units of proteins are amino acids. • Used also to create the essential enzymes within the body • Foods that are richest in essential amino acids are animals proteins and milk • Proteins in the body are part of either tissue structures or part of the metabolic system such as transport, hormone or enzyme systems • • We Do not have a protein store Role of providing energy has become increasingly clear that protein metabolism is increased during endurance exercise Anaerobic: 10-15% Aerobic: 15-20% Ensure that adequate fuel is Fuel stores are replenished immediately consumed to facilitate the after the end of exercise intensity and duration of training Supplementation (with vitamins) is Expenditure must undertaken to ensure the body can equal intake utilise the nutrients required Adequate protein is consumed to Hydration is maintained both enable the necessary growth and before and during repair of muscle tissue performance Ensure that fuel stores are full before a performance Ensure that fuel stores are supplemented during the activity as required Carbohydrate Loading A legal method of attempting to boost the amount of glycogen in the body before a competition or event • Aims to super-charge glycogen stores for long duration activity such as a marathon • Achieved by using an intensive training sessions that deplete muscle glycogen stores 7 days prior to competition • For the next 3 days that athlete mainly eats fats and proteins to deprive the muscle of carbs. This has the effect of increasing the activity of glycogen synthase. During this period training is tapered • In the final 3-4 days prior to the event the athlete switches to a carb rich diet and increases fluid intake. Because glycogen synthase has been increased, carb intake now results in increased muscle glycogen storage Competition Day The best time to eat is 2-3 hours prior to the event and meals should be of low volume, contain plenty of carbohydrates and fluids. This is because liver glycogen stores need topping up even in a well nourished athlete The overall effect is for performance times to improve significantly During short events the athlete will need to eat nothing. For long duration events such as the marathon, the athlete will need to eat little but with high carb content for example jelly babies Disadvantages • Increase in body weight since more water is needed to store the glycogen • During depletion, athletes feel week, depressed and irritable British Olympic athletes Linford Rapid weight gains have been found but the Christie, Sally Gunnell reason for this is unclear. Some argue that it’s and many of the due to water retention others that it’s the gain rowing squad all used in muscle mass. creatine in their preparation for the 1992 Olympics • Creatine is effective in treating many muscular, neuromuscular and neurodegenerative diseases • Ingesting creating can increase the level of phosphocreatine in the muscles by up to 20% • Has no significant effect on aerobic endurance though it will increase power in anaerobic exercise • Often taken by those wanting to gain muscle mass • Powder or tablets are the most popular methods • Not considered doping and so is legal • In France the supplement is banned Hydrated Electrolytes Substances containing free ions. They play a vital role in homeostasis in the body helping to regulate and manage the water and fluid levels Combined chemically with water • Essential minerals With water loss comes the additional problem of electrolyte loss. The most important being sodium. • Control osmosis of water between body compartments • Water alone will not be able to rehydrate the performer • Help to maintain the acid base balance required for normal cellular activities Body weight lost as sweat (%) Physiological effect 1 Performance effect Loss of 5% 2 Impaired performance Loss of 10% 4 Capacity for muscular work declines Loss of 25% 5 Heat exhaustion Potential failure to compete 7 Hallucinations Potentially fatal 10 Circulatory collapse and heat stroke Potentially Fatal Plain Water Electrolytes in a drink •Causes bloating and suppresses thirst. • reduce urine output • enable the fluid to empty quickly from the stomach • Stimulates urine output • Contains no carbohydrate or electrolytes • promote absorption from the intestine •Encourage fluid retention Two main factors affect the speed at which fluid from a drink gets into the body: • the speed at which it is emptied from the stomach • the rate at which it is absorbed through the walls of the small intestine How • Record your body weight immediately before and after a number of training sessions along with details of distance/duration, clothing and weather conditions • Add the amount of fluid taken during the session to the amount of weight lost 1kg is approx 1l of fluid • After a few weeks patterns should emerge and you can calculate your sweat rate per hour • Once you know what your sweat losses are likely to be in a given set of environmental conditions, you can plan your drinking strategy for specific events Ensures that you do not lose more than 2% of your pre race weight • Blood will have a typical osmotic value of 5% glucose concentration. • A glucose solution greater than this will empty very slowly into the stomach • A solution lower will enter the blood stream much quicker but this means taking in a lot more liquid • In order to get carbs into the body quickly a low concentration is required but a lot of volume is necessary because of the low concentration • Many sports nutrition companies use glucose polymers which are far less osmotically active. Some drinks can be 50% glucose concentration but still be isotonic. This allows more glucose to be consumed in a smaller volume of drink • Drinks with an osmolality of 270-330mOsm per kg are said to be in balance with the body’s fluid and are called Isotonic • Hypotonic fluids have fewer particles than the blood. • Hypertonic fluids have more particles than the blood Type Content Glucose Content (volume) Isotonic Fluid, electrolytes and 6-8% carbohydrate Similar to blood or the body Hypotonic Fluids, electrolytes and a low level of carbohydrate Less than blood or the body Hypertonic High level of carbohydrate Greater than blood/body Humid Heat • Humidity of the surrounding air prevents the evaporation of perspiration to some extent • Over heating may result 14 Days to fully acclimatise Athletes with a higher VO2 max will acclimatise quicker Dry Heat (Desert Conditions) • Better able to lose heat through sweating • the atmosphere absorbs moisture better • Danger becomes dehydration as the athlete may not realise how much they are sweating as it will evaporate quickly from the skin Adaptations • Expanded plasma volume • Improved control of cardiovascular function •Reduced resting heart rate • Onset of sweating earlier and so the body can stay cooler • Increased Sweat rate • The body’s ability to reduce the amount of sodium chloride lost during sweating (Losses decrease between day 3 and 9 but revert back once acclimatised) Benefits Adaptations may disappear after only a few weeks of inactivity 18-28 days Improved tolerance of heat which allows athletes to perform as they would in normal conditions without incurring heat related illnesses Heat Syncope Heat Exhaustion • AKA fainting • Most commonly diagnosed • Most commonly first 3-5 days of heat exposure • Symptoms vague but can include headaches, dizziness, hyperventilation, vomiting, syncope, head cramps, tachycardia •Due to vascular shunting of blood to skin in order to cool down and the consequent reduction in venous return and drop in cardiac output in turn leading to a drop in blood pressure • Defined as inability to continue exercise in a hot environment Heat cramps Usually in the muscles of the legs, arms and abdomen after several hours of strenuous activity, in individuals who have lost a large volume of sweat, drunk a large volume of hypotonic fluid and who have excreted a small volume of urine. Sodium depletion probably causes heat cramps Training Method Result Live High Train High Maximum exposure to altitude but evidence of a positive effect at sea level is controversial LHTH Live Low Train High LLTH Live High Train Low LHTL Exercise in a low oxygen environment but rest in normal conditions. Some positive findings but still no real evidence of any difference to competitive performance at sea level. Training intensity is reduce so some may loose fitness with this method Live at altitude for more than 12 hrs per day over 3 weeks whilst maintaining training intensity at or near sea level. Improvements in sea level performance have been shown in events lasting 8-20 minutes Effects of Altitude • Partial Pressure of Oxygen is lower • Reduction in driving pressure for oxygen transport • Fall in VO2 max Increases in Erythropoietin (EPO) levels. However after prolonged exposure they return to normal levels Increased myoglobin concentration. This enables tissue to extract more O2 and remove more CO2 Increased VO2 Max Hyperventilation (increased pulmonary ventilation) Increased muscle and tissue capillarisation Increased mitochondrial density. Enables greater and faster production of ATP Increased Red blood cell and haemoglobin concentration. (known as polycythaemia) It may take 3 months for the body to have an optimum level of red blood cells.