File - PE Course Specification

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Specialised Training
Learning Objectives:
1. To understand how elite athletes use
specialised training methods to develop
power, flexibility and endurance.
2. To understand the theories behind carboloading.
3. To know how training schedules can be
broken down to maximise their effect.
4. To know how training intensity can be
accurately measured.
Specialised Training
To maximise performance elite athletes use
specific specialised training methods to
improve fitness and technique.
Plyometrics
With a partner discuss what this is and which
component of fitness it is designed to
improve.
• Upper Body Plyometrics
• Lower Body Plyometrics
How Plyometrics Works
• Plyometrics is a type of training designed to produce fast, powerful
movements.
• It involves bounding, jumping or hopping to make muscle groups work
eccentrically before a powerful concentric contraction. Plyometrics
involves explosive muscular contractions that engage the stretch reflex (a
protective mechanism that prohibits overstretching of muscle fibres and is
detected by muscle spindles).
• A muscle that is eccentrically stretched before a concentric contraction
will contract more forcefully and more rapidly. (think about how you
prepare for a vertical jump).
• Plyometrics movements involve 3 phases:
1. Eccentric contraction during the downward movement.
2. A very short phase during which you change from eccentric contraction
(lengthening, downward) to concentric contraction (shortening,
upward).
3. The actual contraction of the muscle being trained.
PNF Training
With a partner discuss what this is and which
component of fitness it is designed to
improve.
• PNF Tutorial
How PNF Stretching Works
• Proprioceptive neuromuscular facilitation uses alternating
contraction and relaxation movements to increase flexibility (range
of motion around a joint).
• PNF facilitates the body’s muscular inhibition.
• Isometric (no movement) muscle contraction is performed.
• This is immediately followed by a passive stretch until muscle
spindles cause the muscle to contract to prevent overstretching
(stretch reflex).
• The Golgi Tendon Organ is stimulated and causes the muscle to
relax.
• The muscle is then actively isometrically contracted and the process
repeats.
• PNF training is potentially dangerous and requires a long aerobic
warm up, is easiest to do with a partner, should not be done on
morning of competition and requires 48hrs rest between sessions.
Exam Revision
• Exam questions on plyometrics and PNF
training will be concerned with the theory of
how it works and the practical understanding
of exactly how it is done.
• Both of these methods are quite complicated
and it is recommended that you review these
YouTube clips as well as going through the
more in depth notes on these (p61-65 A2 PE
textbook).
Altitude Training
• Triathlete altitude tent
• England U20 altitude training
Why Does Altitude Training Work?
• Aerobic performance is enhanced because the body
adapts to lower levels of oxygen by increasing the
concentration of red blood cells and haemoglobin.
• When the athlete returns to sea level they still (for
10-14 days) have an increased level of RBC thus
improving performance.
• As well as increasing rate of transports oxygen, the
body is also able to buffer lactate more effectively.
Altitude Training Schedule
Three Phases when training at altitude:
1. Acclimatisation – starts immediately on arrival. Light training, lots of
recovery time. (lasts 3-10 days).
2. Primary training – progressively increase training until it is at same stage
as at sea level. (lasts 1-3 weeks).
3. Recovery – prepare to return to sea level. Reduce training load to relieve
fatigue. (lasts 2-5 days).
Three Phases when returning to sea level:
1. Positive phase – in first 1-4 days. A visible increase in oxygen carrying
capacity of blood.
2. Progressive return to sea level – a dip in performance due to altered
fitness levels.
3. Fitness Peak – after 15-20 days. Optimal time for competition.
Combination of improved oxygen transport and maintenance of
breathing adaptations.
• It is advantageous to live (or sleep) at altitude whilst training at sea
level.
• There are few places where this is possible so hypoxic chambers
(altitude tents) have been developed. Thousands of athletes use
these.
Negatives:
• Sceptics claim that the benefits actually wear off within a few days
of returning to sea level.
• Some argue that the reduced capacity to train at altitude actually
lowers fitness levels (or skill levels).
• Considerable cost and travel time involved.
• Risk of altitude sickness.
• Psychological problems of being away from family.
• Fatigue caused by long distance travel.
Overall, research is still inconclusive about the benefits/hinderance of
altitude training.
Glycogen Loading (carbo-loading)
• Glycogen stores last only about 60-90 mins.
• After this the body resorts to slower fat
metabolism (‘hitting the wall’ in a marathon).
• Therefore athletes try to boost there levels of
glycogen by taking on more prior to the event.
• There are several theories of the best way of
doing this:
First Theory of Glycogen Loading
• Necessary to deplete glycogen stores through
heavy exertion before ingesting a high carb
diet (supercompensation).
• This does increase glycogen stores.
• However, athletes were left fatigued (through
the heavy exertion) and bloated/lethargic.
Second Theory
• To avoid the previous problems athletes
simply increase their intake of carbs in the
days leading up to an event, whilst tapering
down training levels.
• This worked sometimes, but not for everyone.
A new theory!
• New research has produced a method of creating
extremely high muscle glycogen levels in just one day.
• It is based on the concept that very high intensities of
exercise stimulate higher rates of muscle glycogen storage
than moderate intensities of exercise carried out over
prolonged periods.
• A 3-min burst of intense exercise is followed by 24hr high
carb eating (starting no more than 20mins after exercise).
• This opens a ‘carbo window’ in muscles when glycogen
stores can be increased dramatically. The ‘window’ closes
2hr after exercise.
• There will be no risk of bloating and no requirement to
alter training.
Periodisation
Dividing your overall training programme into
parts or periods that are designed to achieve
different goals.
• Task: Read p69/70 of A2 textbook.
• Periodisation of training can be broken down
into: Microcycles, Mesocycles, and
Macrocycles.
Microcycle:
• A repeating group / pattern of training sessions.
• E.g. mon-weights, tues-circuits, weds-rest etc.
• Generally between 3-7 days.
Mesocycle:
• A block of training (microcycles) with one goal.
• E.g. A rugby player with the goal of improving scrummaging performance.
• Generally 4-12 weeks.
Macrocycle:
• A long term training plan with a long term goal (e.g. Preparation for a
competition).
• Made up of several mesocycles.
• Generally 10-12 months.
• Could also use large macrocycles consisting of a few smaller macrocycles (e.g. A
two year training plan).
A common form of periodisation is ‘wave-like periodisation.’ This involves building
up the total quantity of training while intensity reaming fairly low to establish basic
strength and endurance. Intensity then increases as quantity reduces. The
moment of peak intensity is the optimum point for competition.
Tapering, Peaking and Overtraining
• Overtraining – the physical and mental fatigue
due to excessive training without adequate
recovery.
• Tapering – reducing the amount of training (or
intensity) prior to competition.
• Peaking – making sure that both body and mind
are at their best for competition.
It is impossible to be at your very best all of the
time. It is therefore essential that top athletes
have a good knowledge of these issues in order
to be at their best when it matters most.
Thermoregualtion
It is essential that we maintain a steady core
body temperature of around 37 degrees.
During exercise heat is produced. To remove
this heat blood is moved closer to the surface
of the skin and heat is lost through: conduction
(direct contact), convection (transfer of heat by
air molecules), radiation (main way of losing
heat during rest), and evaporation (sweating,
main way of losing heat during exercise).
Sweating
• Cools the body as heat is lost when sweat evaporates from the skin.
• When humidity is high, sweat evaporation is limited.
Internal Body Temperature
• Regulated by the thermoregulatory centre in the hypothalamus of the brain.
• Responds with mechanisms such as vasodilation, sweating, vasoconstriction,
shivering.
The Blood
• During exercise in hot conditions a large amount of blood must be shared by the
skin (to cool the body) and working muscles. This reduces the amount of blood
returning to the heart, reducing stroke volume and sporting performance.
The Heart
• In hot conditions the body can suffer from hyperthermia (high body temperature).
• Aerobic ability is reduced in high temperatures. HR increases to provide blood flow
to the skin. Fatigue is more rapid.
Fluid Intake
• Heat exposure can lead to hypohydration (dehydration). This has a great negative
effect on sporting performance.
• It is essential to rehydrate regularly (remember that thirst is a poor indicator of
dehydration).
Measuring the Intensity of Training
Lactate Sampling:
• Elite athletes need to train at an intensity near their VO2
max.
• It is essential that training intensity can be accurately
measured.
• Lactate sampling involves taking a minute sample of the
performers blood to detect the level of lactate present.
• If lactate levels rise above resting levels during exercise it is
because anaerobic exercise is taking place.
• The lactate threshold is 2mmol above resting levels (OBLA
is 4mmol).
• The higher the intensity of exercise at which lactate
threshold occurs, the fitter the athlete.
The Respiratory Exchange Ratio
• The ratio of CO2 released to O2 used by the body (VCO2/VO2).
• Used to estimate relative contributions of fat and carbohydrate to
ATP resynthesis.
• RER works because fat and carbohydrate differ in terms of the
amount of O2 used and CO2 produced during energy production.
• When fat is the major fuel the amount of O2 being consumed will be
high and RER will be low (and vice versa for carbs).
• RER is measured used a cycle ergometer and a gas analyser.
• When RER is 0.70, 100% of energy is coming from fat. When RER is
1.00, 100% of energy is coming from carbs.
• Fat is not used as an anaerobic energy source. RER can therefore be
used to determine whether exercise is aerobic or anaerobic.
• The use of lab equipment limits this to cyclists, rowers and runners.
Over to you...
• These slides cover an enormous amount of
information (p61-78 of A2 textbook). Much of
this info has been greatly condensed.
• Extended learning task: review these notes
and then use your textbook for greater detail.
• Answer questions 1-4 on p78 to ensure that
you have understood the information.
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