Physical and Physiological Factors Affecting Sport Performance PDF

Summary

This document provides lecture notes on the physical and physiological factors affecting sports performance. The document details the different energy systems involved in exercise, including the phosphagen system, anaerobic glycolysis, and aerobic metabolism, along with their interaction and recovery.

Full Transcript

C o ll e Physical and Physiological Factors g e N a m Affecting Sport Performance e – ‫ا‬ ‫س‬ ‫م‬ ‫ا‬ ‫ل‬ ‫ك‬ ‫ل‬ ‫ية‬ Dr. Moizuddin Khan ‫حاضرة حسب التقويم‬0‫ رقم ا‬Class No. according to Calendar Objectives By the end of this lecture students should be...

C o ll e Physical and Physiological Factors g e N a m Affecting Sport Performance e – ‫ا‬ ‫س‬ ‫م‬ ‫ا‬ ‫ل‬ ‫ك‬ ‫ل‬ ‫ية‬ Dr. Moizuddin Khan ‫حاضرة حسب التقويم‬0‫ رقم ا‬Class No. according to Calendar Objectives By the end of this lecture students should be able to : Explain Muscle metabolic systems in exercise- ◦ Adenosine triphosphate ◦ Nutrients used during muscle activity ◦ Phosphocreatine-creatine system ◦ Glycogen-lactic acid & aerobic system me – ‫اسم الكلية‬ Explain Recovery of the muscle metabolic systems after exercise& Oxygen debt- Recovery of muscle glycogen Discuss Effect of smoking on pulmonary ventilation in exercise Correlate Effect of heart disease and old age on athletic performance Discuss Body fluids and salt in exercise Interpret Effect of Drugs on athletes & how Body fitness prolongs life ‫قرر‬0‫ – اسم ورقم ا‬Course Name and No. 11/30/2024 2 ‫حاضرة حسب التقويم‬0‫ رقم ا‬Class No. according to Calendar C o ll Metabolic pathways in skeletal muscle e g e Adenosine triphosphate (ATP) is the energy source used N a m directly by muscles for contractile activities. e – The demand and the mechanism of ATP production vary ‫ا‬ according to the type of work done. ‫س‬ ‫م‬ Loading… At rest, a muscle cell contains a small store of ATP, but it ‫ا‬ ‫ل‬ cannot rely on this ATP once it begins contracting. ‫ك‬ ‫ل‬ Muscle cell must get ready to ATP production to keep pace ‫ية‬ with the increased rate of utilization. ‫حاضرة حسب التقويم‬0‫ رقم ا‬Class No. according to Calendar Energy for Muscle Contraction Mitochondria in the muscle converts glucose, fatty acids, and amino acids into ATP Adenosine-PO3 ~ PO3 ~ PO3 Each of the last 2 high energy phosphate bonds in ATP stores 7300 calories per mole of ATP. All me – ‫الكلية‬ ‫ اسم‬ATP stored in the muscle is sufficient for only 3 seconds of muscle power. (Enough for half of a 50-meter dash). So resting muscles must have energy stored in other forms e.g Creatine Phosphate (CP), glycogen, etc. 4 ‫حاضرة حسب التقويم‬0‫ رقم ا‬Class No. according to Calendar C o ll e ATP regeneration g e As we begin to exercise, we almost immediately use our stored ATP within few N seconds. ATP is regenerated by 3 pathways: a m 1-Direct phosphorylation of ADP by Creatine phosphate (CP). e – 2-Anaerobic pathway (glycolysis lactic acid). ‫ا‬ ‫س‬ ‫م‬ Loading… 3-Aerobic oxidation of fatty acids in the mitochondria ‫ا‬ ‫ل‬ ‫ك‬ ‫ل‬ ‫ية‬ 5 ‫حاضرة حسب التقويم‬0‫ رقم ا‬Class No. according to Calendar INTERACTION OF ENERGY SYSTEMS Immediate Short- Long-term term me – ‫اسم الكلية‬ ‫حاضرة حسب التقويم‬0‫ رقم ا‬Class No. according to Calendar C o ll 1-Phosphocreatine-creatine system (creatine ˜ Po3) e g e Direct phosphorylation CP: Contain high energy N phosphate bond of 10,300 Coupled reaction of creatine a Phosphate (CP) and ADP calories/mole. m e Energy source: CP Most muscle cells have 2- 4 – ‫ا‬ times as much CP as ATP. Creatine ‫س‬ kinase ‫م‬ Energy transfer from CP to ‫ا‬ Creatine ATP occurs within a small ‫ل‬ fraction of a second. ‫ك‬ Oxygen use: None Energy of muscle CP is ‫ل‬ Products: 1 ATP per CP, creatine ‫ية‬ immediately available for contraction just as stored energy of ATP. 7 ‫حاضرة حسب التقويم‬0‫ رقم ا‬Class No. according to Calendar Phosphagen energy system: Formed of combined amounts of cell ATP + CP Together provide maximal muscle power for 8-10 seconds (enough for 100 me – ‫اسم الكلية‬ meter run). Energy of phosphagen system is useful for maximal short bursts of muscle power ( 8-10 seconds). ‫حاضرة حسب التقويم‬0‫ رقم ا‬Class No. according to Calendar C 2- Glycogen-Lactic acid System (anaerobic Metabolism) o ll Anaerobic pathway e Glycolysis and lactic acid formation g e Energy source: glucose N a m e Glucose (from – glycogen breakdown or ‫ا‬ delivered from blood) Anaerobic ‫س‬ – Without oxygen Glycolysis ‫م‬ in cytosol – Source of energy: ‫ا‬ Carbohydrate ‫ل‬ 2 (glycolysis) ‫ك‬ Pyruvic acid – Lactate & ATP net gain ‫ل‬ Released Lactic acid ‫ية‬ to blood Oxygen use: None Products: 2 ATP per glucose, lactic acid Duration of energy provided: about 40 seconds, or slightly more 9 ‫حاضرة حسب التقويم‬0‫ رقم ا‬Class No. according to Calendar Anaerobic Glycolysis (Glycogen-Lactic acid system) ◦ Is the primary energy source for peak (sever) muscular activity. Produces 2 ATP molecules per molecule of glucose. The process of anaerobic metabolism can maintain ATP supply for about 40-60s. me – ‫اسم الكلية‬ Glycogen Glucose 2 pyruvic acid (2 ATP + 2 NADH) 2 Pyruvic acid 2 lactic acid (2 NAD+) Lactic acid diffuses out of muscles blood taken by the liver Glucose (by gluconeogenesis) blood taken by the muscle again. ‫حاضرة حسب التقويم‬0‫ رقم ا‬Class No. according to Calendar C o ll e g Anaerobic metabolism is ineffective… for long duration Why? e N a Large amounts of glucose are used for very small ATP returns. m e Lactic acid is produced whose presence contributes to muscle – ‫ا‬ fatigue. ‫س‬ ‫م‬ Which type of sports uses anaerobic metabolism? Loading… ‫ا‬ ‫ل‬ Sports that requires bursts of speed and activity, e.g., basketball. ‫ك‬ ‫ل‬ ‫ية‬ ‫حاضرة حسب التقويم‬0‫ رقم ا‬Class No. according to Calendar 3- Aerobic Metabolism Aerobic pathway Aerobic cellular respiration Energy source: glucose; pyruvic acid; free fatty acids from adipose tissue; amino acids from protein catabolism Glucose (from glycogen breakdown or delivered from blood) Aerobic me – ‫اسم الكلية‬ With oxygen Pyruvic acid Fatty Source of energy: acids mainly fatty Amino Aerobic respiration acids, then acids in mitochondria carbohydrate, amino acids 32 net gain per CO2, H2O & glucose ATP Oxygen use: Required Products: 32 ATP per glucose, CO2, H2O Duration of energy provided: Hours 12 ‫حاضرة حسب التقويم‬0‫ رقم ا‬Class No. according to Calendar C o ll Aerobic Metabolism e g Is the primary energy source of resting muscles (to convert glucose into e N glycogen. and to create energy storage compounds as CP). a m e During rest and light to moderate exercise, aerobic metabolism – ‫ا‬ contributes 95% of the necessary ATP. ‫س‬ It breaks down fatty acids, pyruvic acid (made via glycolysis), and ‫م‬ ‫ا‬ amino acids. ‫ل‬ ‫ك‬ Produces 32 ATP molecules per glucose molecule. ‫ل‬ ‫ية‬ ‫حاضرة حسب التقويم‬0‫ رقم ا‬Class No. according to Calendar Figure 9.20 Comparison of energy sources used during short-duration exercise and prolonged-duration exercise. Short-duration exercise Prolonged-duration exercise me – ‫اسم الكلية‬ 3 seconds 10 seconds 30–40 seconds End of exercise Hours ATP stored in ATP is formed from Glycogen stored in muscles is broken down to glucose, ATP is generated by breakdown muscles is creatine phosphate which is oxidized to generate ATP (anaerobic pathway). of several nutrient energy fuels by used first. and ADP (direct aerobic pathway. phosphorylation). 14 ‫حاضرة حسب التقويم‬0‫ رقم ا‬Class No. according to Calendar C o ll e g e N a m e – ‫ا‬ ‫س‬ ‫م‬ ‫ا‬ ‫ل‬ ‫ك‬ ‫ل‬ ‫ية‬ ‫حاضرة حسب التقويم‬0‫ رقم ا‬Class No. according to Calendar Recovery of muscle metabolic systems after exercise Energy from CP reconstitute ATP. Energy from glycogen-lactic acid system reconstitute the phosphagen system (CP+ATP). Energy from oxidative metabolism of aerobic system reconstitute all other me – ‫الكلية‬ ‫ اسم‬systems:-glycogen-lactic acid system & CP&ATP. Lactic acid causes fatigue so it should be removed by: 1. Portion converted into pyruvic acid that is oxidized by all body tissues. 2. The remaining is changed into glucose in the liver to replenish glycogen stores of muscles. ‫حاضرة حسب التقويم‬0‫ رقم ا‬Class No. according to Calendar C o ll Recovery of aerobic system after exercise e g e N Oxygen Debt a m Oxygen Debt is the amount of extra O2 that must be taken e – after exercise to restore the muscles to the resting ‫ا‬ ‫س‬ conditions. ‫م‬ ‫ا‬ ‫ل‬ When a person stops exercising, the rate of oxygen uptake ‫ك‬ ‫ل‬ does not immediately return to pre-exercise levels; it returns ‫ية‬ slowly (the person continues to breathe heavily for some time afterward). This extra oxygen is used to repay the oxygen debt ‫حاضرة حسب التقويم‬0‫ رقم ا‬Class No. according to Calendar Oxygen Debt is about 11.5 L of O2 1. 2 L of stored O2 (0.5 L in lungs + 0.25 L dissolved in body fluids+1.0 L combined with Hb + 0.3 L stored in muscle myoglobin) -This is used within a minute of heavy exercise or for aerobic metabolism. 2. 9 L more O2 to reconstitute the phosphagen & glycogen-lactic acid systems. me – ‫اسم الكلية‬ At first O2 uptake is high & fast to refill stored O2 & phosphagen system ( this is called alactacid O2 debt= 3.5 L) The later portion of O2 debt takes 40 minutes for lactic acid system removal, it is of lower level breathing, it is called (lactic acid O2 debt =8 L) ‫حاضرة حسب التقويم‬0‫ رقم ا‬Class No. according to Calendar C o ll Recovery of muscle glycogen e g e -Reduction of glycogen stores by heavy exercise needs days to be replenished. N a -On high CHO diet, recovery occurs in 2 days. m e – -On high fat, high protein or on no food all show very little recovery. ‫ا‬ ‫س‬ Message: ‫م‬ ‫ا‬ 1- Athlete should have high CHO diet before exercise. ‫ل‬ ‫ك‬ 2- Not to participate in exhausting exercise during 48 hours preceding the event. ‫ل‬ ‫ية‬ Read Guyton & Hall: Textbook of Medical Physiology 13E ‫حاضرة حسب التقويم‬0‫ رقم ا‬Class No. according to Calendar Nutrients used during muscle activity During early stages of exercise body use CHO of muscle and liver glycogen. In intense muscle activity the body uses fats and very little amino acids. me – ‫اسم الكلية‬ If endurance athletic events last longer than 4-5 hours & during exhaustion muscle glycogen is depleted & muscle depend on fats. Glucose solution given to athletes to drink during athletic event supply 30-40% of energy required during prolonged event as marathon race. ‫حاضرة حسب التقويم‬0‫ رقم ا‬Class No. according to Calendar C o ll Effects of smoking on pulmonary e g ventilation in exercise e N Nicotine constricts the terminal bronchioles and increases resistance a m of airflow into and out of the lungs. e – Smoke irritation causes increased fluid secretion into the bronchial ‫ا‬ ‫س‬ tree and swelling of epithelial layer. ‫م‬ Nicotine paralyze the cilia of the respiratory epithelial cell surface. ‫ا‬ ‫ ل‬ All lead to fluid and waste accumulation and reduced level of ‫ك‬ ‫ل‬ performance. ‫ية‬ Chronic smokers may develop Emphysema (obstruction of bronchioles+ chronic bronchitis+ destruction of alveoli) so slight exercise cause respiratory distress. ‫حاضرة حسب التقويم‬0‫ رقم ا‬Class No. according to Calendar Effects of heart disease and old age on athletic performance Cardiac diseases that reduce cardiac output (C.O.P) will reduce muscle power. Patient with congestive heart failure has me – ‫اسم الكلية‬ little muscle power to even walk on the floor. There is 50% in C.O.P between age 18-80 yrs, in maximal breathing capacity, in muscle mass and therefore in muscle power with age. Read Guyton & Hall: Textbook of Medical Physiology 12E ‫حاضرة حسب‬0‫ رقم ا‬Class No. according to Calendar ‫التقويم‬ C o ll Effect of body fluids and salts in exercise e g e Exercise for 1 hour -causes 5-10 pounds of weight loss in hot humid N a atmosphere due to sweat loss. m e Loss of enough sweat reduces performance 5-10% and may lead to – ‫ا‬ cramps, nausea & serious effects, so it should be replaced. ‫س‬ Sodium tablets and supplemental fluids containing potassium in ‫م‬ ‫ا‬ the form of fruit juice is required to athletes. ‫ل‬ ‫ك‬ Acclimatization to exercise by gradual increase over 1-2 weeks instead ‫ل‬ of maximal exposure is needed. ‫ية‬ ‫حاضرة حسب التقويم‬0‫ رقم ا‬Class No. according to Calendar Drugs and athletes Caffeine increase athletes performance. Male sex hormone (Androgens) & other anabolic steroids increase athletes performance but they ◦ Risk of heart attacks due to hypertension, LDL and HDL. ◦ Women develop facial hair, stoppage of menses, ruddy skin and bass voice if they take androgens. me – ‫اسم الكلية‬ Amphetamine & cocaine improve performance but overuse reduce performance they are psychic stimuli. -the action of these drugs in addition to epinephrine and norepinephrine (hormones of adrenal medulla) secreted during exercise leading to death by ventricular fibrillation. Read Guyton & Hall: Textbook of Medical Physiology 12E ‫حاضرة حسب التقويم‬0‫ رقم ا‬Class No. according to Calendar C o ll e Body fitness prolongs life g e Body fitness, exercise &weight control have additional benefit N a of prolonged life (between 50-70). m e Reasons:- – ‫ا‬ 1. It reduces CVD, heart attacks, brain stroke and kidney ‫س‬ ‫م‬ disease due to low blood pressure, low blood cholesterol, ‫ا‬ ‫ل‬ low LDL, and high HDL. ‫ك‬ 2. ‫ل‬ It reduces insulin resistance and type 2 diabetes. ‫ية‬ 3. Improved fitness reduces the risk of breast, prostate, and colon cancers and reduces obesity. ‫حاضرة حسب التقويم‬0‫ رقم ا‬Class No. according to Calendar me – ‫اسم الكلية‬ Thank you ‫حاضرة حسب التقويم‬0‫ رقم ا‬Class No. according to Calendar

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