A2 PHYSICAL EDUCATION PERFORMANCE ENHANCEMENT

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Transcript A2 PHYSICAL EDUCATION PERFORMANCE ENHANCEMENT

A2 PHYSICAL EDUCATION
PERFORMANCE ENHANCEMENT
PERFORMANCE
ENHANCEMENT
DIETARY MANIPULATION
DIETARY MANIPULATION
PRE-COMPETITION
• Carbohydrate (CHO) Loading is a dietary strategy aimed
at increasing the body’s glycogen stores prior to an
event to improve performance time
• This involves a 10-day programme
– High intensity exercise for 7 days before an event to
deplete muscle glycogen stores
– In the first 3 days a diet high in fat and protein is consumed
to fully deprive the muscles of CHO, whilst on a reduced or
tapered training load (this increases the activity of
glycogen-synthase, which helps break down glycogen)
– High CHO and fluid diet 3-4 days prior to the event along
with low fat and protein consumption on a low training
load (this loads muscles with glycogen)
– More glycogen is able to be stored due to the increase in
Glycogen-synthase
DIETARY MANIPULATION
SUMMARY OF CARBOHYDRATE LOADING
POSITIVE EFFECTS
Increases muscle
glycogen levels
prior to
competition.
NEGATIVE EFFECTS
Quality of training may
suffer with low
glycogen levels.
Athlete may gain
weight due to water
retention.
USERS
Longdistance
Aerobic
athletes
LEGAL
STATUS
Legal
DIETARY MANIPULATION
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COMPETITION DAY
CHO-rich meal 2-4 hours before an event tops up liver
glycogen stores
High volumes of food and fibre-type foods should not
be consumed in the days leading up to the event
(which can cause digestive problems)
CHO should be avoided one hour before the event
(which can cause a decrease in muscle glycogen stores)
as this may cause rebound hypoglycaemia, which may
actually decrease muscle glycogen stores and bring on
earlier onset of muscle fatigue
Consuming a chocolate bar 5 minutes before an event
can actually provide an energy fuel during the activity
DIETARY MANIPULATION
SUMMARY OF PRE-EVENT MEALS
POSITIVE EFFECTS
NEGATIVE EFFECTS
Muscle glycogen
levels and liver
glycogen stores
are high. Glucose
can be eaten just
before exercise.
If meal is eaten 15-45
mins before exercise
it can cause early
exhaustion.
USERS
Games
players
and
Aerobic
athletes
LEGAL
STATUS
Legal
DIETARY MANIPULATION
DURING EXERCISE
• Performers should consume frequent but small
amounts of food or drink high in CHO during
activity of 45 or more minutes (this replenishes
vital glycogen stores and delay’s fatigue)
• There is less need to consume CHO during
exercise if the duration is less than 45 minutes
• Examples of CHO food consumed during exercise
include bananas, glucose tablets, gels and sports
jelly beans, or the preferred CHO drink
DIETARY MANIPULATION
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FLUID INTAKE DURING EXERCISE
The state of Hydration (water content) changes from at
rest to different exercise conditions
If you feel thirsty then you are too late for hydration
Water intake during prolonged exercise reduces the
risk of dehydration and optimises performance
Dehydration will increase the temperature and with
have a detrimental effect on performance (possibly
leading to heat exhaustion)
Hydrating the body before an event will help to prevent
dehydration etc
DIETARY MANIPULATION
SUMMARY OF FOOD/FLUID INTAKE DURING
EXERCISE
POSITIVE EFFECTS
Consuming small
amounts of carbs
maintains blood
glucose level.
NEGATIVE EFFECTS
USERS
LEGAL
STATUS
Feeling
uncomfortable when
exercising. Gastro
problems may occur.
Athletes
performin
g longer
that 45
mins
Legal
DIETARY MANIPULATION
TYPES OF SPORTS DRINKS
• Hypotonic drinks have lower levels of glucose than blood
(about 4% glucose). They are vital during prolonged
exercise. Drinking 4-8g of CHO per 100ml solution every 1015 minutes reduces the risk of dehydration and provides a
partial energy supplement
• Isotonic drinks promote fluid hydration and replenishment
of glucose during endurance events of more than one hour.
They have equal levels of glucose as the blood (5-7%
glucose)
• Hypertonic drinks are suitable as a recovery drink postactivity as they have higher levels of glucose (19%). These
increase dehydration, so should not be consumed during
the activity, as water is needed to help dilute CHO as it is
converted into glycogen/glucose
DIETARY MANIPULATION
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POST COMPETITION
The body can break down and convert CHO to
glycogen/glucose better within the first 2 hours of recovery
(which speeds up recovery)
Adding protein to CHO consumed in the first hours postexercise may stimulate glycogen recovery rates in
performers involved in several consecutive bouts of highintensity activity over a period of days
There is a 45 minute window of opportunity for optimal
refuelling after activity (e.g. a meal or drink high in CHO
and protein)
CHO stores used up in short duration exercise can be
replenished in a few hours (recovery will depend on the
intensity and duration of exercise)
If stores are depleted after long duration activity, then
recovery will take longer (sometimes days)
DIETARY MANIPULATION
SUMMARY OF POST-EVENT MEALS
POSITIVE EFFECTS
NEGATIVE EFFECTS
Liver glycogen stores None
are replaced within
hours. Muscle
glycogen
replacement is much
quicker during the
first 2 hours after
exercise.
USERS
Athletes
using
carbs for
energy.
LEGAL
STATUS
Legal
PERFORMANCE
ENHANCEMENT
OTHER AIDS TO PERFORMANCE
CREATINE SUPPLEMENTS
• Creatine is made up of amino acids (building blocks of
protein) and can be found in some animal foods and in
liver/kidneys
• Creatine is stored in muscles as creatine phosphate (PC) which
is used to resynthesise ATP
• Creatine supplements can be taken as part of a performers
diet to increase the performer’s PC levels and help improve
the ATP/PC system’s efficiency
• Creatine is readily available in shops and is legal, despite
showing that it can increase performance
• It is suggested that unless high volume intensity training is
undertaken alongside creatine supplements then there may
be an increase in body mass/non-lean mass which is not
desirable for any activity
SUMMARY OF CREATINE
POSITIVE EFFECTS
Can maximise PC
stores in the
muscles.
NEGATIVE EFFECTS
USERS
Can put strain on the High
organs like the liver. Intensity
Can increase
athletes.
dehydration.
LEGAL
STATUS
Legal
HUMAN GROWTH HORMONE (HGH)
• HGH is produced naturally in the pituitary
gland and helps the body to grow and develop
• HGH can also be synthetically produced and
used by athletes as a substitute or to
compliment the use of anabolic steroids as it:
– Stimulates bone, cartilage and muscle growth
– Increases blood glucose levels
– Increases lipases for the breakdown of FFA’s
– Decreases overall body fat
– Stimulates protein synthesis in skeletal muscle to
enhance healing after musculo-skeletal injuries
HUMAN GROWTH HORMONE (HGH)
• HGH is produced more in youth and adolescence but still in
adulthood to a lesser degree to assist in some metabolic
processes
• HGH secretion can be increased by following a healthy
lifestyle with plenty of exercise and having lots of sleep
• HGH abuse can lead to:
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Joint pain
Arthritis
Abnormal heart/liver growth
Muscle weakness
Increased blood fats
Glucose intolerance
Diabetes
Impotence
Hypertension
It is also against the law
SUMMARY OF HORMONES
POSITIVE EFFECTS
Increase muscle mass
and strength and may
aid in recovery of highintensity training. HGH
increases the amount
of glucose in the blood
and increase the
capability of the body
to heal.
NEGATIVE EFFECTS
Similar to Anabolic
Steroids, plus:
USERS
High
intensity/sh
ort duration
Bones thicken and deform. athletes.
Internal organs to increase
dangerously in size.
Diabetes and high blood
pressure.
LEGAL
STATUS
Illegal
GENE DOPING
• Gene doping is too complex to discuss in real
detail at this level
• There is a Human Gene Map for Performance and
Health-Related Fitness Phenotypes which is
updated every year. This lists the genes which, in
different combinations, could hypothetically
produce a so-called “genetically engineered super
athlete” for different sporting disciplines like
aerobic endurance or anaerobic power
• A company called Genetic Technologies (a biotech
company based in Australia) claims to be able to
identify whether a child has the genetic make-up
to excel in either sprint and power sports or
endurance sports
GENE DOPING
• Detailed knowledge of a sports person’s ‘genetic
expression’ would be extremely useful for predicting
their trainability and therefore the specificity of
training regimes
• The main problem with gene doping is that athlete’s
will have no control over the gene and therefore will
not be able to shut down the gene production
• Although gene doping is banned, if genes are
introduced into the tissue, e.g. into the muscle and not
via a drug, it would be virtually undetectable by any
current doping control technology
• Even with DNA testing it would not be clear if the
athlete inherited it or used gene doping
• Below is a table of examples of genes and how
performers benefit from them
GENE DOPING
GENE
EFFECTS
ACE-II Improves efficiency of mitochondria.
Normally 70% of the fuel energy given off as
heat (ACE-II diverts % heat energy into
making extra ATP)
PERFORMERS
BENEFITING
Extra ATP has been
shown to improve
aerobic endurance
IGF-1 Increase in enzyme activation for increasing Strength/power
the uptake of amino acids to increase muscle activities/performers
growth/regeneration and strength
BLOOD DOPING
• This is where a person’s total volume of red blood cells
(RBC’s) is increased
• In order to do this it involves the removal (transfusion)
and storage of blood from a performer about 4-6
weeks before an event
• The body then compensates for this blood loss by
replenishing its RBC’s to restore its haemoglobin levels
• Just before the event, the blood is then reinfused into
the performer, which increases the overall
RBC/haemoglobin volume
• An increase in RBC/haemoglobin helps the
transportation of O2 available to the muscles during
exercise
SUMMARY OF BLOOD DOPING
POSITIVE EFFECTS
Increases RBC and
Hb levels.
NEGATIVE EFFECTS
USERS
Put Heart under
Endurance
strain (possibly cause athletes.
blood clots and Heart
failure).
Contamination
problems.
LEGAL
STATUS
Illegal
RECOMBINANT ERYTHROPOIETIN
(RH EPO)
• The hormone erythropoietin (EPO) is found naturally
in the body and is secreted by the kidneys
• A small amount is found in the blood to
regulate/increase the RBC production to maintain it at
basal rate
• Rh EPO is an artificial synthetic copy of EPO which is
injected into the body and produces the same results
as blood doping (the increase of production of
RBC/haemoglobin levels and raises O2 transport)
• Testing procedures detect high levels of
RBC/haemoglobin, which result in athletes being
suspended from competitions
RECOMBINANT ERYTHROPOIETIN
(RH EPO)
• Some athletes use fluids just before testing to
dilute the blood. These fluids are now also on the
banned list of substances
• Rh EPO is now being used by strength/power
athletes, not just endurance athletes
• Some athletes have naturally high concentrations
of EPO and this can cause problems when testing
• Therefore, athletes should be tested early on in
their career’s to produce a baseline value to
measure against at a later stage
SUMMARY OF EPO
POSITIVE EFFECTS
NEGATIVE EFFECTS
USERS
Increases RBC and Put Heart under strain Endurance
(possibly cause blood athletes.
Hb levels.
clots and Heart
failure). Don’t know
how the body will
react to it. More
danger of blood clots
LEGAL
STATUS
Illegal
PERFORMANCE
ENHANCEMENT
COOLING AIDS AND RESISTANCE
AIDS
COOLING AIDS
• These are used prior to an activity to reduce core body
temperature to help improve performance or after the
activity to improve the recovery process
• The main methods include cold air exposure, water
immersion/ice baths, fan cooling, cold water spraying,
body/head cooling jacket/vest, cold therapy
packs/wraps or simply packing ice into damp towels
• Cold air exposure and water immersion have been the
predominant methods used, but are not practical for
most performers
• Cooling jackets/vests are highly practical and are made
from wet suit material and packed with ice
PRE-COOLING
• Using a cooling jacket or ice-packed towels aims to reduce skin
temperature and consequently core body temperature
• It should last between 8-30 minutes during warm-ups and /or
the intervals between warm-ups and the start of performance
• Temperature guidelines vary between 5 and 16 degrees Celsius
• Pre-cooling is advisable before prolonged exercise in hot
temperatures as it helps to sustain intensity and speed, reduces
thermal strain, allows for different pacing strategies and
increases exercise intensity towards the end of performance
• Metabolic and cardiovascular responses (reduced heart rate and
inaccurate perceived exertion) can be affected during the first 15
minutes of exercise after pre-cooling
• Cooling the body too much will hamper the performance and
pose a health risk
POST-COOLING AND ICE
WRAPS/PACKETS
POST-COOLING
• Cooling treatments used as part of recovery (cryotherapy)
may be used in different ways on acute and chronic injuries
• The benefits of cooling on damaged soft tissue is now
widely accepted
• The application of ice in the treatment of injuries to soft
tissues to reduce swelling and blood leaking into the tissues
has been a long term method, accompanied by
compression, elevation and rest (RICE)
ICE WRAPS/PACKETS
• They are used as part of RICE to help provide immediate
treatment and to speed up recovery of any soft tissue
injuries
ICE BATHS
• These have been used for their pain-relieving properties in the
treatment of injuries
• More recently the belief is that:
– Blood vessels constrict and blood flow is drained away from that
muscles that have been working (removing lactic acid)
– Once out of the bath the capillaries dilate and ‘new’ blood flows back
to the muscles, bringing with it oxygen that will help the functioning of
the cells
• This process is thought to improve muscle function, reduce muscle
damage and decrease soreness associated with DOMS
• Therefore, this not only treats injury and pain, but helps with injury
prevention and exercise recovery
• Ice baths are popular in contact sports (Rugby and Football) and
with endurance athletes
• Whole-body ice baths would be used for contact sports like Rugby
and for Football, running, Hockey etc, only immersion of the lower
limbs would be needed
ICE BATHS
• The process involves the performer immersing body parts at a
temperature between 5-16 degrees Celsius for 7-10 minutes (shorter for
pain relief)
• Initially start with 1 minute sessions and progress to a maximum of 10
minutes over a period of 10 weeks
• Once in the ice bath, athletes should keep moving around to prevent
warm water from forming around their limbs
• However, there are various concerns with the use of ice baths:
– Different individuals have different sensitivity to ice (some find it immediately
painful)
– If used on the chest the cold may cause muscle reaction, bringing about
angina pain from constriction of coronary arteries
– Check skin sensitivity/touch before applying ice as it may indicate nerve
impingement and ice will hide or complicate the problem
– Do not use with high blood pressure as vasoconstriction will increase blood
vessel pressure
– There is decreased efficiency with vasoconstriction (particularly affecting older
people)
– The ice burns if place directly onto skin and can cause tissue/vascular
impairment if held on the skin for too long (more than 10 minutes)
RESISTANCE AIDS
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PULLEYS
These provide a form of resistance to apply force against to
develop strength, in the same way as weights on a multigym
The main advantage of pulleys is that they better meet the
principle of specificity as they can match more closely the
actual movement patterns used in the performance of an
activity
A cheaper alternative to pulleys are elasticated resistance
bands, which do not replicate the smoothness of
movements that pulleys offer
Swimmers can benefit from pulley resistance/ergometertype machines that allow them to lay flat and replicate the
movement patterns of various strokes against a resistance
during the arm action
RESISTANCE AIDS
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PARACHUTES
These increase the resistance to apply a force against while
maintaining the movement
They are used predominantly in sprint-type running
activities
These are a better form of resistance training than lifting
weights with the legs while the body is in a sitting or
standing position
The downside is that parachutes make athletes run with a
slower arm and leg action which is not specific to sprinting
Although there is no solid evidence that parachutes
improve sprint performance in comparison to conventional
training, it provides fun and variety to a training regime
Ankle and wrist weights are two other forms of resistance
aids which are comparable with parachutes
PERFORMANCE
ENHANCEMENT
OTHER PERFORMANCE
ENHANCEMENT AIDS
ALCOHOL
• Alcohol has no real benefits to sport
performance, although it does act as a
carbohydrate (CHO) source of energy
• It does also provide a temporary psychological
effect of calming, anxiety reduction and
confidence building
• In the long-term alcohol is primarily a depressant
and research shows that alcohol decreases both
motor skill and physiological performance
SUMMARY OF ALCOHOL
POSITIVE EFFECTS
NEGATIVE EFFECTS
None. Although can Impairs psychomotor
make athlete feel performance. Speeds
more relaxed and up dehydration.
confident.
USERS
None
LEGAL
STATUS
Legal
(over
18’s)
CAFFEINE
• Caffeine can be found in tea, coffee, cocoa, most soft
drinks, many foods and in some medications
• Caffeine stimulates the central nervous system (CNS) and
acts like a weak amphetamine (stimulant) which increases
alertness, concentration and reaction time
• It produces increased breakdown of FFA’s, increases energy
levels and lowers perception of effort
• Some athletes take in caffeine prior to exercise to increase
the breakdown of FFA’s to save their important glycogen
stores
• Caffeine is not banned, however, the International Olympic
Committee (IOC) have a limit beyond which performers
should not consume (around 7-8 strong cups of coffee)
• Caffeine also acts as a diuretic, increasing urine production
and can increase dehydration and therefore heat regulation
SUMMARY OF CAFFEINE
POSITIVE EFFECTS
NEGATIVE EFFECTS
USERS
LEGAL
STATUS
Can help improve
mental alertness,
concentration and
reaction time. Reduce
the feeling of fatigue,
which allows athletes
to exercise at higher
intensities for longer.
Increase the ability to
utilise fats as a fuel
and increase aerobic
capacity.
Increase the sensation of
nervousness, anxiety
and restlessness.
Disturbed sleep. Risk of
dehydration. It is
addictive.
Endurance
athletes (for
increase of
fat
metabolism)
Legal
ANABOLIC STEROIDS
• These are synthetically copies of the naturally
produced hormone testosterone, which promotes
bone maturation and development of muscle mass
• They are thought to help repair muscle tissue and
recovery after exercise
• They come in the form of tablets, capsules, a solution
for injection and a cream or gel to rub into the skin
• The anabolic (building) effect is dependent on the
dosage
• These are used for medical reasons for rehabilitation
and muscle wastage diseases
• They are also commonly used by body builders and
weight lifters
SUMMARY OF ANABOLIC STEROIDS
POSITIVE EFFECTS
Increase muscle
mass and strength
and may aid in
recovery of highintensity training.
NEGATIVE EFFECTS
USERS
Affect the balance of
sex hormones (women
= reduction in breast
size, hair growth and
develop a deeper
voice, Men = larger
breasts, reduction in
size of their penis).
Acne, weak joints and
aggressiveness.
High
intensity/
short
duration
athletes.
LEGAL
STATU
S
Illegal
ANALGESICS/ANTI-INFLAMMATORY
AGENTS
• Analgesics come in the form of non-steroidal aspirin
and ibuprofen, but also in the form of steroidal
cortisone injections (unless accompanied by a medical
note)
• These relieve pain and act as anti-inflammatory agents
to relieve swelling
• They are often taken in combination after soft tissue
injuries to relieve pain/inflammation
• Analgesics and anti-inflammatory agents are often
used prior to competition to mask pain in order to
allow performers to compete
• If used in this way there is likely to be further and more
severe injuries
MASKING AGENTS
• These all have the same aim, which is to
prevent the identification of other agents,
normally a banned illegal agent
• If masking agents are detected they are
classified as a positive test in the same way as
the substance they would be hiding would
have done
• Diuretics are a common masking agent that
increase urine production to help athletes to
flush steroids out of their system