Unit 2 - Physical Health

1. Unit 2 - Physical Health How Exercise Affects the Systems of Your Body

2. Physical Health • How well your body functions • Why exercise? • Can help prevent: • Cardiovascular disease • Certain cancers • Diabetes • High Blood Pressure • Improves Stamina, Flexibility, and Strength • Controls Weight • Improves Quality of Life • Affects both social and mental health

3. Physical Health • Affects every system in your body • Key systems to be discussed: • Cardiovascular • Respiratory • Muscular • Skeletal • Nervous • Brain

4. Cardiovascular System • Cardiovascular System – AKA the Circulatory System – is an organ system that encompasses the heart and blood vessels of the body • Function - carries blood, oxygen, and nutrients to organs and tissues of the body, and carries waste and carbon dioxide from these tissues for removal from the body • Heart causes blood to flow away from the heart • Bodily movement causes blood to efficiently flow back to the heart • Muscles pressing on veins help push blood back towards the heart • The heart is a constantly working muscle

5. The Heart • Any exercise will strengthen muscle • More exercise = stronger heart • Stronger heart = less work to do at rest • Higher cardiac output – more blood is expelled from the heart per beat • Less work to do at rest = lower resting heart rate (RHR) • More exercise = better blood and oxygen flow

6. Blood Vessels and Pressure • Increased exercise will increase cardiac output and lower heart rate • Helps regulate fluid and promotes capillary formation • Amount of fluid in blood greatly determines blood pressure • More fluid = more pressure

7. Respiratory System • Function - to supply the blood with oxygen in order for the blood to deliver oxygen to all parts of the body • Made up of • Mouth • Nose • Trachea • Lungs • Diaphragm

9. Respiratory System • Improves lung capacity • Blood flow increases to alveoli • Allows better Oxygen / CO2 exchange

10. Respiratory System • Controls mucus which may settle in the lungs • Increases endurance of Diaphragm and Intercostals

11. Muscular System • Helps with strength and endurance • Supply and demand • The more you exercise, the more demand there is on your muscles which leads to an increase in strength and endurance • More exercise = more blood flow = increased muscle growth

12. Diagram of a Skeletal Muscle

13. Muscular System • Increase workload = increased stress on muscles • Increased stress result in micro-tears in muscle fibers • Natural repair process repairs the tear • Overcompensates by adding bigger cells to build a stronger fiber. • Over time, this repeated process of teardown and re-build will result in muscle growth Hypertrophy – muscle growth • Your body does not actually make more muscle but the muscle fibers which make up your muscle get larger

14. Muscular System An established exercise routine results in an increase in Mitochondria in muscles • Mitochondria use oxygen to create energy • Glucose + Pyruvate + NADH = ATP (adenosine triphosphate) • Process occurs because of the presence of oxygen Increase in number of blood vessels in muscle tissue

15. Muscular System • Skill - a learned ability to bring about the result you want with maximum certainty and efficiency • Four components a skill must have: • It is learned • Has an end result • Should be performed under control • Should use the minimum amount of energy

16. Muscular System Learning a new skill… • Information Processing • When we are learning a new skill our brains must take in, process and use a lot of information about the skill and environment. Four steps for information processing when learning a new skill take place…

17. Muscular System • Input – information your brain receives (what you see, hear, and feel) • Decision Making –  brain processes this information and decides how to react • Output – a result of your decision • Feedback – shows success or failure

18. Muscular System Two types of feedback • Intrinsic – how performing the skill felt • Extrinsic – effectiveness of the performance and judgment by coaches, parents, teammates, etc. • Did the ball land where you wanted it to? • Did your coaches tell you how to perform better?

19. Muscular System • Skills are either basic or complex • Basic Motor Skills • Most are learned at an early age • Transferable between different sports and situations • Must be mastered before moving on to complex skills • Examples - running, hopping, dodging an opponent • Complex Motor Skills • Require more coordination and control • Tend to be specific to a particular sport (i.e. non-transferable) • A lot of practice to master • Examples - smash shot in badminton, a tennis serve, basketball lay-up

20. Muscular System • Skills can be either open or closed • Open Motor Skills – affected by external factors • Hitting a pitched baseball will be affected by your position, the position of your opponents, the type and speed of pitch, playing conditions, previous at-bats, etc. • Closed Motor Skills -  performance is self-controlled with very little effect from environment or other people • Successfully throwing a dart to a specific target is completely in the individual’s control.

21. Muscular System • Open and closed continuum • Most skills fall in between open and closed • The more outside factors there are, the more open a skill will be Why is goaltending in hockey more closed than competitive sailing? Which is a more open skill, hitting a ball off of a tee or hitting a pitched ball? • Why?

22. Muscular System Neuromuscular effects • Neuromuscular system is the interaction between your muscles and the nerves that control them • Increase in repetitive exercise = more muscle fibers to be activated and better timing of muscle contractions • Leads to increased strength and coordination

23. Muscular System • Two types of practice • Blocked and random • Blocked - a learner performs a single skill over and over, with repetition being the key • 50 free throws, 50 elbow jumpers, 50 baseline jumpers

24. Muscular System • Random – a learner works on a number of different skills in combination with each other, randomly working trials and patterns of one and then the next and the next • One 17-foot jump shot, back pedal to your three-point line, side-shuffle in defensive stance across the court, dribble a basketball, make a chest pass, cut to the basket, box-out for a rebound

25. Muscular System Which do you think leads to better learning?

26. Muscular System • Blocked – performing an action over and over again without break causes the individual to stop thinking about the solution • Becomes a mindless activity • Evidence shows it leads to a false sense of accomplishment when practicing in controlled, blocked sessions. • Used for beginners learning a new, complex motor skill

27. Muscular System • Random • Forces the learner to become more actively engaged in the learning process by preventing simple repetitions of actions. • Gives the learner more meaningful and distinguishable memories of the various tasks, increasing memory strength and decreasing confusion among tasks. • Causes the learner to forget the short-term solutions (from working memory) to the movement problem after each task change. •  Forgetting the short-term solution forces the learner to generate the solution again on the task’s next trial, which is beneficial to learning. • “Forgetting facilitates learning”

28. Muscular System • Major points: • Physical activity promotes strength, endurance, and coordination • Circulatory and nervous system adapt to physical demands • Practicing new motor skills places demand on the neurons in your brain to work harder to learn how to master the skill • Basic before complex • Continuous relearning leads to retention

29. Skeletal System • Consists of: • Bones, ligaments, and cartilage • Functions - support, movement, protection, blood cell production, calcium storage and endocrine regulation

30. Skeletal System Diagram of a Bone

31. Skeletal System • Bones • Contain marrow that produce blood cells • Ligaments • Fibrous connective tissue attached to bones and many internal organs • Helps limit movements induced by tendons • Keeps internal organs in place • Cartilage • Holds some bones together, helps in the formation of bones in growing children and prevents bones from rubbing each other.

32. Skeletal System • Physical Activity promotes: • Increased synovial fluid production • Maintains and increases joint range of movement • Increased bone density • Stronger ligaments

33. Skeletal System • Synovial Fluid – oil-like fluid produced at joints to keep cartilage lubricated and nourished • Production of synovial fluid is an acute (short-term) response to exercise • More exercise means = more synovial fluid • Joints need regular exercise to stay lubricated, nourished and healthy. • More fluid = better range of motion • Lack of exercise causes joints to “dry up”

34. Skeletal System • Increased Bone Density • Weight-bearing and cardiovascular exercises put stress on bones • Body responds by creating osteoblasts • Osteoblasts – cells which build new bone and make bones stronger and denser • Increased bone density helps prevent osteoporosis • Osteoporosis – weakening of bone

35. Skeletal System • Stronger Ligaments • Ligaments are exposed to the same stresses of exercise • Slowly develop strength

36. Nervous System – The Brain • More exercise = better blood flow to the brain • Exercise causes the release of endorphins which make you feel good • Studies show consistent exercise = better brain development in children • Underuse will result in a decline in function

37. The Brain • Exercise seems to slow or reverse the natural declination of brain function starting in our twenties. • New studies seem to show that adult brains are capable of neurogenesis (creation of new brain cells) • Adults were previously thought to be unable to do this • Exercise is thought to jumpstart neurogenesis • Exercise seems to prompt an increase in Brain-Derived Neurotropic Factor (BDNF) • Exercise does not have to be exhaustive!

38. The Brain BDNF: • Strengthens brain cells and axons • Fortifies connections among neurons and sparks neurogenesis • Most people have higher levels of BDNF in blood after exercise • This does not fully explain all the brain changes associated with exercise