Chapter One: Short term physiological
- Created by: hparkinson10
- Created on: 10-03-17 13:22
Why warm up?
•Prepare body physically and mentally. •Improve performance •Reduce injury
Stages of warm up:
1) Pulse Raiser (gross motor skills-big movements-run/cycle/row)
2) Injury Prevention (Stretch)
3) Skill Practise (Focus on Skill or set of Skills)
4) Sport Specific (Game Situation)
Acute physiological responses to warm up Skeletal
Skeletal
- production of synovial fluid
- Increased ROM [range of movement]
Muscular
- increased temperature of muscle
- increased muscle elasticity
- increased speed of nerve impulse
Acute physiological responses to warm up CV, Respi
CV
- increased HR
- increased SV [stroke volume] and Q [cardiac output]
-Vascular shunting
Respiratory
- breathing rate increases
- tidal volume increases
Psychological
- increase in adrenaline
- Increased neuro-muscular connection
Physiological Repsonse and Functional Benefits to
Physiological response
-Synovial fluid / ROM -HR and SV and Q -Muscle temperature / elasticity /nerve impulses -Breathing rate / tidal volume -Adrenaline / n-c connection
Functional benefit
pre-load the muscles with 02
- raise HR and breathing rate to allow quick response to activity
- more rapid muscle action allowing quicker response time
Physiological Repsonse and Functional Benefits to
Physiological response
- synovial fluid / ROM
- Muscle elasticity
Functional benefit
- increase ROM – better skill level
- reduce injury
Physiological Repsonse and Functional Benefits to
Physiological response
- neuro-muscularconnection
- adrenaline
Functional benefit
- better reactions
Physiological Repsonse and Functional Benefits to
Physiological response
- neuro-muscular connection
- adrenaline
Functional benefit
- better reactions and mental alertness
Static Stretching:
- stretch and hold
- up to 30 seconds
- relax and repeat
- cool down
- Safe stretch after injury
- After any activity
Dynamic Stretching:
-Controlled stretch taking the joint through full range of movement
- tends to be main warm up stretch
- team games
Ballistic Stretching:
-Uses momentum to forcibly stretch
- mimics sporting movement
- throwing events
PNF Stretching:
- Partner holds limb
- Isometric [not moving] contraction for 6 seconds then relaxed
- Partner then pushes limb past normal ROM for 30 seconds – allow 30 seconds recovery
- Not to be used in warm up
- advanced form
-Part of training -Pushes stretch further -Gymnastics -Diving -Trampolining
Passive and Active Stretching:
Passive-
- Stretch using body part or partner
- Forces the stretch further
-Athletics
Active-
- Stretch without the use of body part or partner
- all activities
Warm up duration and intensity:
•Duration – ‘not in minutes but in objectives.’ •A certain amount of time must be allowed for the warm up but time is not the overriding factor. •Eg: Tour De France time trial of 60 minutes Chris Froome will allow 90 minutes to warm up. At the moment his body and mind are at optimum level the warm up is done – this could be 70/80/90 minutes
Chris Froome warm up - specifics:
•Begin at low intensity to generate localised heat •Gradually increase intensity until he reaches ‘race pace’ •Body begins to thermoregulate •Short periods of anaerobic intensity [despite being predominantly aerobic activity] – this helps to encourage the breakdown of lactic acid •Cold? - longer warm up with lower starting intensity •Warm? – shorter warm up at lower intensity but add hydration and avoid overheating
Energy Systems and Energy Sources:
•Energy comes from carb’s, fats and proteins called macronutrients •Energy is stored as glycogen in the muscle and liver •The store of liver glycogen which is gradually released into the blood as glucose. This energy can be used immediately by the muscle cells, stored in the muscle or stored as fat •The store of muscle glycogen serves as a rapid energy source and can last approx. 90 minutes. •Glycogen is broken down in a process called glycolysis during both aerobic and anaerobic activity. •When energy is required from fat reserves the fats are converted to free fatty acids which are sent to the liver for conversion to glycogen.
Carb's, Fats and Proteins:
Carb's- High Intensity Fuel Source.
Used When- Exercise is at an intensity which cannot be maintained by the metabolism of fats in the aerobic energy system.
Fats- Low Intensity Fuel Source, Insulation.
Used When- Intensity of exercise is medium to low and energy requirments can be met by the metabolism of fats in the aerobic energy system.
Proteins- Muscle tissue and growth/repair and energy.
Used When- Emergency Source of energy when performer has exhausted supply of carbohydrates. E.G. At the end of an ultra distance event such as the ironman triathlon.
Creatine Loading:
•Ingesting creatine either as powder mixed in a drink or in tablet form can increase PC levels by up to 20%. •Used by anaerobic performers requiring longer time in the ATP/CP system. •Mixed results on the effect – best in sprint cyclists. •Legal in most countries – but banned in France.
Supplements Key Facts:
Carbohydrates- Main Fuel Source/Maximise body glycogen/ reduces aerobic fatigue.
Sports Drinks- Maintain fluid levels/maintain electolytes, sodium and potassium.
Creatine- Maximise Creatine Stores/Maximise ATP resynthesis/ enhance power.
Protein- Muscles growth and repair.
Sodium Bicarbonate- Buffers lactic acid/extends ability to work anaerobically.
Vitamins- Improve catabolic and metabolic reactions/boosts immunity levels.
Ginseng- Reduces Fatigue.
Caffeine- Stimulant.
Hydration – why important?
•Thermo-regulation •Replace fluid lost by sweat and respiration •Reduces drop in performance •Lubricates joints •Responsible for movement of nutrients in body •Responsible for movement of waste products •Maintains blood viscosity •Maintains plasma levels
Problem with just water?
-bloating
- suppresses thirst
- stimulates urine output
- contains no carbs or electrolytes
Sports drinks:
•Contain the electrolytes sodium and potassium which:- -Reduce urine output - helps fluid empty from stomach - promotes absorption -Encourages fluid retention •Factors which effect rate of absorption:- -Speed emptied from stomach -Rate of absorption through wall of small intestine
Hydration in sport applied:
•Drink needs to be mix of water and electrolytes and carbohydrate •The ratio of these ingredients will vary depending on duration and intensity of the event and climatic conditions •The levels of the 3 ingredients affect the drinks osmolality – it’s ability to be absorbed into the blood stream from the stomach •Hypotonic= rapid absorption due to high fluid content. [low osmolality] •Hypertonic = slow absorption due to high carb’ content. [high osmolality] •Isotonic = medium level of absorption due to balance between fluids and carb’s
Recent hydration developments:
•In order for an elite cyclist working at high intensity in high temperatures for a 5 hour race to maintain hydration and carbohydrate levels they would have to take on board at least 5 litres of hypertonic fluid PER HOUR !!!!! • Glucose polymers are added to drinks to allow quick absorption of the carbohydrate which means the performer can have more energy in less fluid.
Eg: Gatorade is used by the Australian cricket team – developed by the AIS.
Altitude acclimatisation:
•Heavyweight world boxing title – Hashim Rahman beat Lennox Lewis with 15:1 odds against at 6,000 feet ASL in South Africa in 2001 •1968 Mexico Olympics was held at 6,000 feet ASL. The following records were broken and some stood for decades after – 100m, 200m, 400m, 800, long jump, triple jump and pole vault
Altitude:
•At altitude partial pressure of 02 is reduced – therefore it is not forced into the lungs at the same amount as sea level – reducing max V02. •Hypoxia = ‘a shortage of 02 in the body.’ •Hypoxemia = ‘low concentration of 02 in arterial blood’ •Training – research has shown that it is best to [LHTL]:-
- live high – normally sleeping in a hypoxic chamber for at least 3 weeks but 3 months for full effect.
- train low – at sea level – which allows training to be at levels the performer is used to.
Altitude training – physiological effects:
•Increased:- •EPO release •Haemoglobin [up by 12%] •Vascularisation – more blood carrying capacity •Myoglobin – more 02 carrying capacity in the muscle •Mitochondria – faster rebuild of ATP •Aerobic enzymes •Better buffering
Of lactic acid
Acclimatising to heat:
•Dry heat – the body loses heat by sweating which can evaporate quickly – causing dehydration and hyperthermia.
•Adapting to heat
- people with high max v02 adapt more quickly.
- acclimatisation to heat can take place in 14 days
Acclimatising to heat-Physiological responses/adap
Physiological Responses [short term – up to 5 days] to heat:-
- expanded plasma volume
- improved control of cv function
- reduced HR
-Nervous system habituation – redirects blood to surface to aid sweating [away from muscles which affects performance] •Physiological adaptations - Longer term:-
- increased sweat rate / earlier onset of sweat production
- cv adjustments
- reduce loss of sodium chloride in sweat
- better at thermal regulation
Heat acclimatisation – the issues:
•Heat cramps – caused by sodium depletion after long endurance activity. •Heat syncope – fainting caused by vascular shunting of blood to skin causing drop in blood pressure. •Heat exhaustion – mix of dizziness / fatigue / nausea
Acclimatising to other factors:
•Wind
- cycling – make cyclist and machine as low drag coefficient as possible [wind tunnel testing for bike / clothing / riding position]
- sailing – selection of sails / setting up the boat for the conditions / sailing technique / choice of sailor for conditions [weight]
•Pollution
- Big factors in longer distance events such as triathlon / cycling and marathon – affecting breathing processes. Beijing Olympics 2008.
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