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Principle of Adaptation. Training Adaptations. Principle of Adaptation. Athletes train to adapt their bodies to a particular sport/activity. Training should be; Specific to their sport Specific to the desired outcome as a result of adaptations. SAID Principle
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Principle of Adaptation Training Adaptations
Principle of Adaptation Athletes train to adapt their bodies to a particular sport/activity. Training should be; • Specific to their sport • Specific to the desired outcome as a result of adaptations. SAID Principle S = Specific A = Adaptation I = Imposed D = Demands Adaptation = “a long-term physiological change in response to training loads that allows the body to meet new demands. Stress on the body causes adaptations. A plateau occurs when the training load is not sufficient to cause stress. Adaptations can be classified as acute and chronic; Acute – Immediate physiological response to exercise which last the duration of the exercise session. Type of training not important. Chronic – Long-term adaptations to exercise. In this chapter, we will focus on chronic changes. VCE Physical Education - Unit 4
Anaerobic and Aerobic Adaptations Training Adaptations
Anaerobic Energy System Adaptations Anaerobic Training the ATP-PC and lactic acid systems cause; • Increased levels of anaerobic enzymes and fuels (See fig. 11.2 p.263) • Increase in glycolytic capacity • Improvements at the muscular level in both systems Aerobic Improvements in; • Oxygen uptake • Transport and utilisation of oxygen • Fat breakdown as a fuel • Fatty acid oxidation and respiratory ATP production • Lactate Infection Point (See fig 11.5 and 11.6 p.265) • Reduced carbohydrate use during sub-maximal exercise • Increased use of blood glucose – assisting in glycogen sparing. • Increased capillarisation, mitochondria density and oxidative enzymes. VCE Physical Education - Unit 4
Cardiovascular Training Adaptations Training Adaptations
Cardiovascular Training • Cardiac Hypertrophy - Heart increases (Left ventricle) in size as a result of training. This increases the stroke volume (SV) • Increased capillarisation - (Coronary blood supply) of the heart – increases blood flow to the heart. • Increased stroke volume - thus reducing HR. • Lowered resting heart rate (Increase in SV causes a decrease in HR when Q is constant – approx 5 litres) • Lower heart rate during sub-maximal workloads – Due to increased SV. • Improved heart-rate recovery rates – Due to increased SV • Increases cardiac output at maximum workload – Constant at rest, but Q can reach up to 30L/min in elite athletes. • Cardiac Output = Stroke Volume x Heart Rate Q = SV x HR Example Q = 5L SV = Q/HR Before training HR = 71bpm therefore the SV = 0.07L/beat After training program HR=50bpm. SV now = 0.1L/beat VCE Physical Education - Unit 4
Cardiovascular Training • Lower blood pressure– relieves hypertension by lowering resistance in the vessels • Arterio-venous oxygen difference - increases as athlete is able to use oxygen from arteries more effectively (see fig 11.13 & 11.14 p.271) • Increased plasma, blood volume and haemoglobin levels • Increased capillarisation of skeletal muscle • Decreased blood cholesterol, triglycerides ad Low Density Lipoproteins (LDP). These substances are associated with coronary heart disease. • Increased high density lipoproteins (HDL) – Ratio of HDL to LDL increases, which is important for heart health. • Increased redistribution of blood – Training can lead to a 20% increase in blood flow to working muscles. VCE Physical Education - Unit 4
Respiratory Training Adaptations Training Adaptations
Respiratory Training Adaptations • Decreased minute ventilation- Lungs become more efficient as a result of training. Ventilation is therefore reduced at sub-maximal workloads. • Increased pulmonary diffusion – oxygen is more readily extracted from the alveoli • Increased tidal volume (Amount of air inspired and expired during breathing) • Ventilatory musculature – Muscles responsible for breathing require less oxygen. • Improved lung function –due to improved lung volume and alveolar capacity surface area. • Aerobic capacity – Improves due to an increase in oxygen supply to the working muscles. See table 11.4 p.273 Increased VO2 max – Due to; • Increase in cardiac output, • Increase in RBC numbers, • Increase in a-VO2 diff • Increase in muscle capillarisation • Improved oxygen extraction. VCE Physical Education - Unit 4
Oxygen extraction: a-V02 difference a-V02 difference = Arteriovenous oxygen difference: “difference in oxygen consumption when comparing that in the arterioles to the venules, and an indirect measure of how much oxygen muscles are using” • An increase in a-V02 difference results in more blood being pumped to active muscles (especially slow-twitch) • Muscle fibres better at extracting and processing oxygen as a result of increased mitochondria numbers, more oxidative enzymes and increased levels of myoglobin. • All of this is due to the oxygen demands of the muscles 12 mL/100mL 18 mL/100mL VCE Physical Education - Unit 4
Muscular Training Adaptations Training Adaptations
Athletes need to use specific training methods to cause muscular adaptations for their sport. Aerobic – Trains the slow twitch (Type I) fibres. Anaerobic – Trains fast twitch (Type II) fibres. Muscle fibre type and percentage that make up the body Muscle fibre type can change, eg for elite endurance athletes from 70-90% Genetics a big advantage to start with x amount of fibre percentage You are born with x amount of fast and slow twitch fibres. BUT you can train and gain more of one type. MYTH – “with training you can change from fast twitch to slow twitch or vice versa.” IMPOSSIBLE HOWEVER – fast twitch fibres have been known to take on slow twitch characteristics in response to aerobic training Muscular Training Adaptations VCE Physical Education - Unit 4
Aerobic (Muscular) • Increased oxygen utilisation – Increased size and number and density of mitochondria • Increased myoglobin stores. • Increased muscular fuel stores ie.Glycogen, fatty acids, triglycerides and oxidative enzymes. • Increased capillary density to slow twitch fibres. • Increased use of fat at sub-maximal levels. • Increased stores and use of intramuscular triglycerides. • Increased oxidation of glucose and fats – Ability to metabolise and extract energy has improved. The body can therefore use ‘glycogen sparing’. • Decreased use of lactic acid system • Some muscle fibre adaptation. VCE Physical Education - Unit 4
Anaerobic (Muscular) • Muscular Hypertrophy – Enlargement of the fast twitch muscle fibres • Increased muscular stores of ATP, PC, creatine and glycogen. • Increased ATP-PC splitting and resynthesis of enzymes • Increased glycolytic capacity – Enhances lactic acid systems ability to use glycogen. • Cardiac hypertrophy – Increases contraction forces exerted by the left ventricle in the heart. VCE Physical Education - Unit 4
Anaerobic (Muscular) • Increased contractile proteins in muscles. • Increased myosin ATPase – Molecule responsible for splitting ATP into ADP • Increased muscle buffering capacity – Muscles able to tolerate higher levels of fatiguing products • Muscle hyperplasia –Research in animals suggest that new muscle fibres may form under stress. • Other – Increase in strength of connective tissue, number of motor units, speed on nerve impulses and muscular contraction speed. VCE Physical Education - Unit 4
Adaptations VCE Physical Education - Unit 4
Adaptations are Reversible Training Adaptations
Adaptations are Reversible Adaptations are reduced and then lost after stopping regular training. See table 11.6 p.281 The reversibility principle applies when an athlete becomes inactive. • As a result, athletes need to undertake a vigorous pre-season months before the in-season starts. • Therefore maintenance in the off-season is required to minimise reversing the adaptations. VCE Physical Education - Unit 4
VCAA Questions - 2006 VCE Physical Education - Unit 4
Australian Sports Commission: http://www.ausport.gov.au • Find 30 promotion (Government of WA Department of Health): http://www.find30.com.au • Walking School Bus promotion (UK): http://www.walkingbus.com • Ministry of Health (New Zealand) toolkits: http://www.newhealth.govt.nz • The 10,000 Steps Rockhampton project: http://www.10000steps.org.au/rockhampton/ • Travelsmart Australia: http://www.travelsmart.gov.au • World Health Organisation: http://www.who.int • Heart Foundation Australia: http://www.heartfoundation.com.au • VicHealth (The Victorian Health Promotion Foundation): http://www.vichealth.vic.gov.au • Be Active promotion (Government of South Australia): http://www.beactive.com.au • Go For Your Life: http://www.goforyourlife.vic.gov.au • Physical Activity Resources for Health Professionals – Introduction (Centre for disease control and prevention – USA): http://www.cdc.gov/nccdphp/dnpa/physical/health_professionals/index.htm • Health Promotion (Public Health Agency of Canada): http://www.phac-aspc.gc.ca/hp-ps/index.html • Strategic Inter-Governmental Forum on Physical Activity and Health (SIGPAH): http://www.nphp.gov.au/workprog/sigpah/ • Healthy youth (Centre for disease control and prevention (USA): http://www.cdc.gov/HealthyYouth/ • America On The Move promotion: http://www.americaonthemove.org • Papers from the International Journal of Behavioural Nutrition and Physical Activity: http://www.ijbnpa.org/home • Department of health and aging (Australian government): http://www.health.gov.au/internet/wcms/publishing.nsf/content/home • Building a healthy, active Australia (Australian government): http://www.healthyactive.gov.au • National Public Health Partnership: http://www.nphp.gov.au • Be Active promotion (Government of South Australia): http://www.beactive.com.au • Sport and Recreation Australia: http://www.sport.vic.gov.au Web Links – Chapter 11 • Australian Institute of Sport, strength and conditioning: http://www.ais.org.au/condition/index.asp • Exercise Physiology – The methods and mechanisms underlying performance: http://home.hia.no/~stephens/exphys.htm • Information about metabolic adaptations and cardiovascular physiology: http://www.unm.edu/~lkravitz/Exercise Phys/cardiopulmonary.html • Sports science library (Gatorade Sports Science Institute): http://www.gssiweb.com/sportssciencecenter/topic.cfm?id=56 • Sport science (site for sports research): http://www.sportsci.org/ • PowerPoint presentation about cardiovascular adaptations from aerobic training (Illinois Wesleyan University – USA): http://www.iwu.edu/~bkauth/330/330-9.PPT • ‘How stuff works’ – How exercise works: http://health.howstuffworks.com/sports-physiology15.htm • Article – Strength Training Basics: http://www.physsportsmed.com/issues/2003/0803/kraemer.htm VCE Physical Education - Unit 4