1 / 60

Sports Physiology

Sports Physiology. Prof. dr. Zoran Vali ć Department of Physiology University of Split School of Medicine. heavy exercise is extreme stresses for body high fever  100%  in metabolism marathon race  2000%  in metabolism. Female and Male Athletes:.

thea
Download Presentation

Sports Physiology

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript


  1. Sports Physiology Prof. dr. ZoranValić Department of Physiology University of Split School of Medicine

  2. heavy exercise is extreme stresses for body • high fever  100%  in metabolism • marathon race  2000%  in metabolism

  3. Female and Male Athletes: • muscle strength, pulmonary ventilation and CO  2/3-3/4 of values recorded in men • strength per cm2 equal (30-40 N/cm2) • marathon race  11% slower • two-way swim across English Channel • Testosterone (40% more muscle mass) • 27% & 15% percent body fat, respectively • aggressiveness

  4. Strength, Power, and Endurance of Muscles • What the muscles can do for you? • What strength they can give? • What power they can achieve? • How long they can continue their activity?

  5. Muscle force (strength): • determined mainly by muscle size (training) • maximal contractile force – 30-40 N/cm2 • quadriceps is 150 cm2 (F=4500-6000N) • rupture & avulsion of tendons, displaced cartilages, compression fractures and torn ligaments

  6. Holding strength (force) of muscles: • force that attempts to stretch out already contracted muscle • greater about 40% than contractile strength • Fquadriceps= 6300-8400N • internal tearing in the muscle

  7. Power of Muscular Contraction: • mechanical work (W) performed by muscle is amount of force applied by the muscle multiplied by the distance over which the force is applied • power (P) is total amount of work that muscle performs in a unit period of time (t)

  8. determined not only by the strength but also: distance of contraction and the number of times that it contracts each minute • power is generally measured in watts (W, or in kilogram meters (kg-m) per minute)

  9. Maximal power of all muscles:

  10. Athletic (muscle) efficiency: • power  efficiency • velocity of 100-meter dash is only 1.75 times as great as velocity of a 30-minute race • depends on muscle supply by nutrients (glycogen)

  11. Endurance (measured by time):

  12. Amounts of glycogen stored in the muscle:

  13. Muscle Metabolic Systems in Exercise: • phosphocreatine-creatine system • glycogen-lactic acid system • aerobic system

  14. Phosphagen system: • ATP (adenosine – PO3 PO3 PO3-) •  high-energy P bonds (7.3 Cal/mol ATP) • amount of ATP sufficient for only about 3 s • phosphocreatine(creatine phosphate, creatine PO3-) • 10.3 Cal/mol creatine, quick transfer • 2-4 x more phosphocreatinethan ATP • combined 8-10 s of maximal muscle power

  15. Glycogen-Lactic Acid System: • glycogen  glucose (glycolysis, anaerobic metabolism) • two pyruvic acid molecules – 4 ATP • without oxygen – lactic acid • 2.5 x more rapid than oxidative mechanism • provides additional 1.3 to 1.6 minutes of maximal muscle activity (200-800 m)

  16. Aerobic System: • glucose, fatty acids, and amino acids

  17. ATP generation per minute:

  18. System endurance:

  19. Reconstitution of the lactic acid system: • removal of the excess lactic acid (extreme fatigue): • small portion is converted back into pyruvic acid • remaining lactic acid is reconverted into glucose (in the liver)

  20. Recovery of the Aerobic System After Exercise: • Oxygen Debt • Recovery of Muscle Glycogen

  21. Oxygen debt: • body contains about 2 L of stored oxygen: • 0.5 L in the air of the lungs • 0.25 L dissolved in the body fluids • 1L combined with the hemoglobin • 0.3 L stored in muscle fibers (myoglobin) • all this stored oxygen is used within minute • 9 L more reconstituting both phosphagen system and lactic acid system • total  11.5 L O2 – oxygen debt

  22. Recovery of Muscle Glycogen: • complex matter, often requires days

  23. it is important for an athlete to have a high-carbohydrate diet before a grueling athletic event • not to participate in exhaustive exercise during the 48 hours preceding the event

  24. Effect of Athletic Training: • muscle strength is not increased without load • 6 nearly maximal contractions performed in three sets 3 days a week – approximately optimal increase in muscle strength, without producing chronic muscle fatigue • 30%  in strength during 6-8 weeks • simultaneously equal increase in muscle mass – muscle hypertrophy

  25. Muscle Hypertrophy: • heredity & testosterone secretion • 30-60 % increase with training • increased diameter of the muscle fibers • increased numbers of fibers?

  26. Changes that Occur Inside the Hypertrophied Muscle Fibers: •  numbers of myofibrils •  mitochondrial enzymes for120% •  ATP and phosphocreatine for60-80% •  stored glycogen for50% •  stored triglyceride (fat) for 75-100%

  27. Muscle Fibers Types: • fast-twitch muscle fibers – (gastrocnemius)– typeII (white, a &b) • slow-twitch muscle fibers– (soleus)– typeI (red)

  28. Basic differences between: • diameter of fast-twitch fibers  2x larger • enzymes for anaerobic metabolism  2-3x more active in fast-twitch fibers (power) • slow-twitch fibers are organized for endurance, generation of aerobic energy (more mitochondria and myoglobin) • slow-twitch fibers – more capillaries • genetic inheritance

  29. % of fiber types in quadriceps:

  30. Respiration in Exercise: • depends on sport discipline, duration of activity

  31. Oxygen Consumption Under Maximal Conditions: • oxygen consumption for • young man at rest is about 250 ml/min

  32. Pulmonary Ventilation (PV):

  33. Limits of Pulmonary Ventilation: • MBC 50% higher thanPV during maximal exercise • respiratory system is not normally the most limiting factor in delivery of oxygen • element of safety if: • exercise at high altitudes • exercise under very hot conditions • abnormalities in respiratory system

  34. Effect of Training on Vo2 Max: • Vo2 Max – rate of oxygen usage under maximal aerobic metabolism • Vo2 Max of a marathoner is about 45 percent greater than that of an untrained person (genetically determined, many years of training)

  35. Oxygen-Diffusing Capacity of Athletes: ME – maximal exercise

  36. 3x increase in DC (activation of the pulmonary capillaries) • training procedures increases DC • partial pressures (O2 & CO2) remain nearly normal during strenuous athletics • regulation of breathing • negative effects of smoking (acute and chronic)

  37. Cardiovascular System in Exercise: • delivering required oxygen and other nutrients to the exercising muscles • arterial blood pressure regulation • flow decrease during each muscle contraction • blood flow to muscles during exercise increases markedly (up to25x)

  38. Maksimalno povećanje protoka:

  39. Mechanisms of Blood Flow Increase: • vasodilation caused by the direct effects of increased muscle metabolism • moderate increase in arterial blood pressure (30%) • muscle pump • FMD • other theories

  40. CO During Exercise:

More Related