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  1. 3 - EXERCISE, HEALTH AND FITNESS 4 - FITNESS 5 - METABOLISM 6 - MEASUREMENT OF ENERGY BALANCE 7 - TOTAL METABOLIC RATE 8 - FACTORS AFFECTING METABOLIC RATE 9 - POSITIVE EFFECTS OF EXERCISE ON HEALTH - WELL-BEING 12 - POSITIVE EFFECTS OF EXERCISE ON SKELETAL HEALTH 13 - POSITIVE EFFECTS OF EXERCISE ON HEALTH - NEUROMUSCULAR 16 - OBESITY 17 - OBESITY AND ENERGY BALANCE 20 - DIABETES 21 - TYPE 2 DIABETES MANAGEMENT 23 - RISK FACTORS FOR CHD 24 - CORONARY HEART DISEASE (CHD) 25 - CORONARY HEART DISEASE (CHD) - CORONARY THROMBOSIS 26 - POSITIVE EFFECTS OF EXERCISE ON HEALTH - CHD AND OBESITY 27 - ENERGY INTAKE 28 - A BALANCED DIET 29 - THE NEED FOR A BALANCED DIET 30 - A FOOD PYRAMID 31 - STORAGE AND RELEASE OF FOOD FUELS 33 - COMPARISON OF DAILY INTAKE 34 - WHEN AND WHAT SHOULD WE EAT BEFORE AN EXERCISE PERIOD? 35 - DIFFERENT DIETS FOR DIFFERENT ATHLETES 36 - PROTEIN REQUIREMENTS FOR DIFFERENT ATHLETES 37 - VITAMINS, MINERALS, SUPPLEMENTS, WATER REQUIREMENTS 38 - WATER BALANCE 40 - HYDRATION INDEX

  2. EXERCISE ‘physical exertion of the body done to achieve a good level of health and fitness both mentally and physically’ exercise can vary from light (for example, a steady walk) to intense (for example, vigorous cycling or running) HEALTH ‘a state of complete physical, social and mental well-being, free from mental and physical disease’ FITNESS ‘the ability to carry out our daily tasks without undue fatigue’ or ‘the successful adaptation to the stressors of one’s lifestyle’ EXERCISE, HEALTH AND FITNESS

  3. PHYSICAL FITNESS the capability to meet physical demands and physiological demands made by a sporting activity HEALTH RELATED FITNESS a state of the body (including mind) compatible with an active and enjoyable life including aspects of physical fitness associated with improving health MOTOR OR SKILL RELATED FITNESS the capability to perform successfully at a particular game or activity FITNESS

  4. ENERGY METABOLISM total intake of food sufficient to supply enough energy to: keep cells alive keep systems working meet demands of life BASAL METABOLIC RATE (BMR) this is the least rate of energy usage needed to carry out basic body functions measured after lying down after 8 hours sleep and 12 hours fasting TOTAL METABOLIC RATE sum of BMR + energy required for all daily activities total average energy usage for 18 year olds in the USA is: females: 8,000 kj per day males 12,000 kJ per day. METABOLISM

  5. MEASUREMENT OF ENERGY BALANCE BODY COMPOSITION • relative percentage of muscle, fat and bone • measured using: • skinfold measurements using the J-P nomogram • body composition scales using bioelectrical impedance analysis • underwater weighing BODY MASS INDEX (BMI) • measures the relationship between weight and height • measured using: BMI = weight in kilogrammes square of body height in metres • a person 1.83m tall weighing 110 kg has: BMI = 110 = 110 = 32.8 1.832 3.35

  6. TOTAL METABOLIC RATE sum of BMR + energy required for all daily activities the total average energy usage for 18 year olds in the USA is 8,000 kJ per day for females, and 12,000 kJ per day for males. metabolic rate contribution by different activities activity energy expenditure over BMR (kJ kg-1 min-1) sitting at rest 0.10 walking 0.26 jogging and swimming (moderate) 0.60 cycling (moderate) 0.46 vigorous exercise 1.09 TOTAL METABOLIC RATE

  7. factors: height muscle mass hormones age pregnancy caffeine smoking alcohol it is important to keep BMR elevated by eating regularly and exercising FACTORS AFFECTING METABOLIC RATE

  8. POSITIVE EFFECTS OF EXERCISE ON HEALTH

  9. CARDIOVASCULAR exercise slows down degenerative diseases (CHD) exercise increases High Density Lipoproteins HDL and decreases Low Density Lipoproteins LDL (LDL are responsible for depositing cholesterol and narrowing lumen of artery) hence stable blood pressure (BP) thus preventing hypertension RESPIRATORY exercise slows down decline in VO2max and hence aerobic capacity remains higher than it otherwise would be hence the capability for long duration low intensity work remains higher POSITIVE EFFECTS OF EXERCISE ON HEALTH

  10. BODY COMPOSITION exercise reduces obesity by burning off excess fat during and after activity when MR remains elevated cardiac workload (hence risk of CHD) less with lower body mass capability to move around (walk, run and climb) therefore better with lower body mass exercise relieves symptoms of osteoarthritis exercise prevents osteoporosis POSITIVE EFFECTS OF EXERCISE ON HEALTH

  11. OSTEOPOROSIS if bones are mechanicallyloaded (by applying forces to the bones along their length) then they tend to respond by becoming stronger greater bone cell wall thickness better calcification of bone tissue hence weight bearing activities will reduce the risk of this condition walking, jogging, weight training, aerobics POSITIVE EFFECTS OF EXERCISE ON SKELETAL HEALTH

  12. NEUROMUSCULAR exercise sustains strength and coordination levels exercise enhances tensile strength and flexibility of tendons and ligaments thus allowing for a fuller range of joint movement POSITIVE EFFECTS OF EXERCISE ON HEALTH

  13. PSYCHOLOGICAL immediately following activity a person experiences a feeling of well being, reduction in anxiety long term increase in work performance, hence a more positive attitude to work improved self-esteem benefits of social interaction hence aerobics as fun for health POSITIVE EFFECTS OF EXERCISE ON HEALTH

  14. POSITIVE EFFECTS OF EXERCISE ON HEALTH

  15. OBESITY

  16. CAUSE OF OBESITY the main cause of obesity is a positive energy balance ENERGY INTAKE > ENERGY OUTPUT or more food than exercise excess carbohydrate (CHO) is stored as glycogen when glycogen stores are filled, CHO together with excess fat intake, is converted to fatty acids and glycerol, and then is stored as triglycerides or fat in adipose tissue adipose tissue is situated around major organs such as the heart and stomach, underneath the skin, and in skeletal muscle upper body obesity poses a significantly greater risk to disease health conditions such as coronary heart disease and hypertension with an increased risk of mortality and morbidity OBESITY AND ENERGY BALANCE

  17. CONTROLLING OBESITY the only method of controlling obesity is to shift the energy relationship so that energy output exceeds energy intake OBESITY AND ENERGY BALANCE • known as a negative energy balance and expressed as: ENERGY OUTPUT > ENERGY INTAKE • a negative energy balance can be achieved with the help of a Weight Loss Plan

  18. WHAT IS A GOOD LEVEL OF FAT? a minimum requirement which would allow full body functions body fat percentage for men is between 2% and 3% and for women between 8% and 12% normally only healthy elite athletes attain these percentages relative body fat is a major concern of sportspeople achieving a desired weight goal can lead to clinical eating disorders such as anorexia nervosa caused by a person restricting food intake to levels well below energy expenditure it is important to have a diet that maintains appropriate weight and body composition to maximise physical performance OBESITY AND ENERGY BALANCE

  19. DIABETES DIABETES • this happens because the Islets of Langerhans situated within the pancreas stop functioning properly and therefore do not produce enough insulin • or the insulin does not facilitateblood glucose to be transferred into cells where metabolism occurs - the cells have insulin resistance • hence cells (particularly muscle cells) will not have enough glucose to function properly - and the person feels exhausted • other symptoms are: • lack of circulation to the hands and feet • extremes of thirst or hunger • unexplained weight loss

  20. when exercise is continued through middle-age and old-age (from 40 onwards), blood glucose is broken down and hence the proportion of glucose carried by blood is reduced and the chances of type 2 diabetes reduced muscle cell walls in people with type 2 diabetes become less permeable to glucose needed for exercise therefore normal levels of insulin cannot transfer blood glucose into the cells for metabolism this is insulin resistance TYPE 2 DIABETES MANAGEMENT

  21. during exercise, muscle contraction increases cell membrane permeability to glucose hence glucose can pass naturally into the cells this in turn means that cell requirement for insulin is reduced (called insulin sensitivity) and so acute bouts of exercise reduce the effects of type 2 diabetes TYPE 2 DIABETES MANAGEMENT

  22. RISK FACTORS FOR CHD

  23. CHD is one of Britain’s greatest killers and encompasses diseases such as angina and heart attacks or coronary thrombosis angina is pain or discomfort felt in the chest usually caused by coronary heart disease angina is normally treated and controlled with drugs and relaxation a person suffering from this condition has a higher risk of suffering from a coronary thrombosis CORONARY HEART DISEASE (CHD)

  24. CORONARY THROMBOSIS heart attack is a sudden severe blockage in one of the coronary arteries, completely cutting off the blood supply to part of the myocardial (heart) tissue this blockage is often caused by a blood clot formed within slowly moving blood in an already damaged, partially obstructed coronary artery heart attacks can be severe or mild, depending on the positioning of the blockage in 2008, Coronary heart disease accounted for 30% of all UK deaths in people aged less than 75 years CHD

  25. CARDIOVASCULAR DISEASES (CVD) include diseases of the heart and blood vessels physical activity reduces LDL (responsible for depositing cholesterol and narrowing the lumen of arteries) fat stores are used during activity and post-activity (to refuel muscle glycogen stores) hence reduce bodyweight OBESITY AND CHD cardiac workload (hence risk of CHD) is less with lower body mass capability to move around (walk or run or climb) therefore better with lower body mass POSITIVE EFFECTS OF EXERCISE ON HEALTH

  26. CORONARY THROMBOSIS heart attack is a sudden severe blockage in one of the coronary arteries, completely cutting off the blood supply to part of the myocardial (heart) tissue this blockage is often caused by a blood clot formed within slowly moving blood in an already damaged, partially obstructed coronary artery heart attacks can be severe or mild, depending on the positioning of the blockage in 2008, Coronary heart disease accounted for 30% of all UK deaths in people aged less than 75 years CHD

  27. ENERGY INTAKE total intake of food sufficient to supply enough energy to: keep cells alive keep systems working meet demands of life ENERGY INTAKE

  28. A BALANCED DIET contains proportions of: carbohydrates, fats and proteins minerals, vitamins, water and roughage (fibre) needed to maintain good health CARBOHYDRATE - 60% principal energy giver FATS - 20-25% storage of energy another source of energy carrier of fat soluble vitamins PROTEIN - 10-15% essential for growth, body building and repair A BALANCED DIET

  29. ENERGY BALANCE when energy input (via food) is equal to energy output (via metabolism including exercise) a neutral energy balance is achieved: ENERGY INTAKE = ENERGY OUTPUT as a result of this body weight will remain constant ACHIEVING A BALANCED DIET decrease dietary fat, especially saturated fats decrease the amount of salt (sodium) increase complex carbohydrates increase minerals such as calcium and iron iron is especially important for females THE NEED FOR A BALANCED DIET

  30. A FOOD PYRAMID fat, butter, margarine, cooking oil fats milk, cheese, yoghurt, eggs, red meat, chicken, fish protein and some fat vegetables and fruit - 5 per day fibre, vitamins minerals carbohydrate and fibre, the bulk of food eaten cereal, pasta, bread, biscuits, cake,

  31. CARBOHYDRATES glucose is absorbed in the small intestine GLUCOSE is utilised as fuel in the liver then stored as liver glycogen transported as glucose in the blood to other tissues (for example skeletal muscle) used as animmediate source of energy or converted and stored as muscle glycogen STORAGE AND RELEASE OF FOOD FUELS

  32. FATS absorbed as fatty acids or glycerol in the small intestine FATTY ACIDS utilised as fuel in the liver stored as triglycerides in adipose tissue or skeletal muscle recalled from fat deposits to the liver converted toglucose (this is a slow process) enters the Kreb’s cycle in aerobic respiration STORAGE AND RELEASE OF FOOD FUELS

  33. Activity daily energy daily energy intake kJ intake kJ females males Tour de France 25000 Triathlon 20000 Rowing 12600 14700 Swimming 8400 15500 Hockey 9200 13400 Soccer 14700 Running 9200 13000 Gymnastics 6000 body building 5900 14500 average USA 18 year olds 8000 12000 COMPARISON OF DAILY ENERGY INTAKE • figures are approximate and for elite athletes • Int.J Sports Med 1989:10:53 MALE FEMALE DIFFERENCES • note that these differences can be mostly accounted for by differences in body mass, with the values of energy expenditure per day per kilogramme of body mass would be similar

  34. WHEN AND WHAT SHOULD YOU EAT BEFORE AN EXERCISE PERIOD? • food should be eaten between 3-4 hours prior to the competition to aid digestion and absorption of nutrients into the bloodstream • the meal needs to be high in carbohydrates, low in fat and moderate in fibre to aid the digestive process • an example meal could be pasta bake with spinach, a banana and a still flavoured drink • a drink (ideally an isotonic drink or water) is essential during this period • with fluid to be taken in sips (to maintain hydration) right up to the time of start of the exercise

  35. DIFFERENT DIETS FOR DIFFERENT ATHLETES BALANCED DIET • a balanced diet from a regular food intake will provide the nutrient requirements for all sportspeople CHO REQUIREMENT • a high CHO diet significantly improves performance • immediate post-exercise CHO supplements, and high glycemic index (GI) foods such as bananas and raisins • will start reloading depleted muscle glycogen stores CARBOLOADING • carboloading can augment endurance performance in events lasting longer than 90 minutes by increasing muscle glycogen stores above normal levels FAT REQUIREMENTS • fat intake should be restricted for both power and endurance athletes • except for power events such as sumo wrestling

  36. PROTEIN REQUIREMENTS FOR DIFFERENT ATHLETES ENDURANCE ATHLETES • the recommended protein intake is 1.2 - 1.4 grams per kilogram of body mass per day STRENGTH AND POWER ATHLETES • need additional protein • 1.4 - 1.8 grams per kilogram of body mass per day • this need for extra protein is because after heavy resistance training the rate of protein breakdown and resynthesis is greater • because of muscle hypertrophy

  37. VITAMINS, MINERALS, SUPPLEMENTS AND WATER REQUIREMENTS VITAMINS AND MINERALS • a regular intake of vitamins and minerals is required for all performers • research has shown that a normal well balanced diet provides all necessary vitamins and minerals to support elite performances • dietary fibre is also needed at a balanced level and must not be neglected for the elite performer SUPPLEMENTS • glutamine has been shown to help immune systems after exercise • creatinehas been shown to increase muscle creatine levels to help sustain power output in power events • a balanced normal diet will contain sufficient glutamine and creatine for this • amino acid or CHO supplementation is often taken in liquid form following exercise - see next slide WATER • exercise is thirsty work, see the following later slides for details

  38. WATER BALANCE water is 60% of total body mass water balanceat rest: water loss occurs via evaporation and excretion, with the majority lost as urine water intake depends on climate and body mass water balance during exercise: more water produced during tissue respiration water loss mainly as sweat determined by external temperature, body mass and metabolic rate and intensity of exercise this also includes mineral loss which must be replaced increased water loss via expired air due to increased breathing age and fitness or acclimatisation levels also affect water loss kidneys decrease urine flow in an attempt to decrease dehydration WATER BALANCE

  39. WATER BALANCE during a marathon 6-10% of body water content is lost, hence the need for water intake during exercise this means that during 1 hour’s exercise an average person could expect to lose around 1 litre of fluid and even more in hot conditions this could represent as much as 2 litres an hour in warm or humid conditions WATER BALANCE

  40. DEHYDRATION AND LOSS OF PERFORMANCE excessive loss of fluid impairs performance as blood plasma volume decreases and body temperature rises extra strain is placed on the heart, lungs and circulatory system which means that the heart has to work harder to pump blood around the body HYDRATION