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Transcript
PDH/PE
Personal Development, Health and Physical
Education
CORE 2: HOW CAN PSYCHOLOGY AFFECT
PERFORMANCE
Nutritional considerations

Athletes need to eat a nutritious, balanced diet to fuel their body. An
adequate diet also avoids the need for supplementation, and delays
the onset of fatigue while aiding the recovery process after a
performance.

Muscles need energy and the major source of energy is
carbohydrates, which are broken down into glucose or stored as
glycogen in the liver or muscle.

Most activity does not use up stored glycogen, so eating
carbohydrates during the activity isn’t usually needed.

But for some athletes, eating or drinking carbohydrates during
exercise or performance helps maintain their blood glucose and
energy levels.
Nutritional considerations

Athletes are more physical than the general population, so they
usually need to alter their diet accordingly.

An athlete competing for less than 60 minutes should have enough
fuel stored without having to replenish carbohydrates during their
performance; however any longer it is better to follow a diet plan,
such as the one in

An athlete’s diet must replicate their training load.

On training days they need to have higher carbohydrate intake.
Nutritional considerations

According to Sports Dietitians Australia, 5–7 grams per kilogram of
body weight per day is the required intake for an athlete, for
example, 350–490 g for a 70-kg athlete.

Athletes on a heavier training requirement should take in 7–12
grams per kilogram of body weight, for example, 490–840 g for a 70kg athlete.
Pre-performance, including
carbohydrate loading

There are various dietary requirements athletes have to consider
prior to performance.

Carbohydrate loading is a strategy involving changes to training and
nutrition that can maximise muscle glycogen (carbohydrate) stores
prior to endurance competition.

It is estimated that carbohydrate loading can improve performance
over a set distance by 2–3%.

For anyone exercising continuously for 60 minutes or longer,
carbohydrate loading is a proven form of boosting endurance, such
as in cycling or triathlon.
Pre-performance, including
carbohydrate loading

The best way to ensure plenty of energy for exercise is to eat a
nutritious, balanced diet that is high in carbohydrates and low in fat
with lots of different foods.

There are two methods of carbohydrate loading.

The traditional method of carbohydrate loading starts 7–10 days out
from competition and involves a decrease of carbohydrates in the
diet with 3–4 days of hard training with carbohydrates stored
maintaining base metabolic rate (BMR).

This has the effect of depleting all stored glycogen and
carbohydrates in the body.
Pre-performance, including
carbohydrate loading

During carbohydrate loading and the depletion phase the athlete
may find increased susceptibility to:

communicable disease, such as the Flu
a general lack of functioning as the body is starved of energy
altered thought processes and actions
lethargy.
This is then followed by 3–4 days of decreased training while




consuming a high carbohydrate diet.
Pre-performance, including
carbohydrate loading

The extra carbohydrates were shown to fill the carbohydrate stores
above normal levels and loads all the cells with glycogen ready for
performance.

At the end of the depletion phase the body will think that there is a
problem with its glycogen stores and any subsequent carbohydrates
ingested will fill glycogen stores above normal capacity.

The other more recommended method, a normal diet is followed 4–7
days out from competition, while training tapers.
Pre-performance, including
carbohydrate loading

In the last three days prior to performance the diet is increased to
70–80% carbohydrates and training is reduced again.

This method has been shown to be beneficial to endurance athletes;
however, more recent research has indicated that there is also a
positive effect on glycogen storage with increased carbohydrate 24
hours prior to competition.
Pre-performance, including
carbohydrate loading

Clearly the trained athlete is much more efficient at storing
carbohydrates than those of the normal population. Replenishment
rates are higher immediately after exercise because of the increase
in insulin sensitivity, making absorption of blood glucose quicker.

If an athlete has less than the suggested carbohydrate percentage,
then this will cause glycogen stores to be depleted and performance
will suffer.

Prior to competition it is suggested that athletes allow 3–4 hours for
a larger sized carbohydrate meal, 2–3 hours for moderate meal and
less than two hours for a light meal or snack.
Pre-performance, including
carbohydrate loading

The type and time of an event will depend on what in particular is
eaten.

This theory may work fine if the activity is in the afternoon, but if the
event is in the morning then a light snack 1–2 hours prior to
competition will top up glycogen supplies.

It may also involve having a larger supper the night before
competition.
Pre-performance, including
carbohydrate loading

All athletes should try out different types of high carbohydrate meals
before competition to see what has a positive effect on their
performance.

Conversely, some athletes may benefit from foods with a low
glycaemic index (GI), and depending on their circumstance this
should be practised during training and competition situations.

It should consist of foods athletes are comfortable with and have
eaten consistently.

Foods that should be avoided include those that are high in fibre,
which may cause the athlete to feel bloated or stomach discomfort,
because these foods take longer to digest as do larger meal sizes.
Pre-performance, including
carbohydrate loading

The food must be taken and digested prior to the start of competition
otherwise it is of no benefit to the athlete.

Stomach discomfort can also be caused by nerves, so the athlete
needs to practise their routine over a period of time to establish that
it is not the food causing the problem, but rather their anxiety which
can affect the digestion rate of food.

It has been proven that a high carbohydrate intake just prior to
competition has an advantageous effect on moderate intensity
activity and helps to top up existing supplies of muscle glycogen.
What is glycaemic index?

The glycaemic index was provided by dietitians to gain a better
understanding of the types of carbohydrates athletes were ingesting.

The simple or complex carbohydrates were categorised according
to their effects on blood glucose levels. As shown in Table 3.4, foods
rated 72 or above are high glycaemic (GI) and are good for
replenishment following a performance.

Foods rated 55–70 are moderate GI and those below 55 are low GI
or slow release carbohydrates.
What is glycaemic index?

Although both high and low GI foods will eventually release the
same energy over time, as shown in Figure 3.3, low GI foods are
thought to have more sustained release over time.

This is of more benefit to endurance athletes rather than the spike
that occurs in high GI foods which are good for an immediate
increase of blood glucose to the system.
During performance

Unless the activity lasts for longer than 60 minutes there is no need
to supplement fluid replacement with some form of carbohydrates.

The decision to take carbohydrates during exercise is dependent on
the length of activity, the intensity and the environment the athlete is
performing in, for example, during hot weather glycogen is quick to
break down.

There are many reasons why athletes will take carbohydrates during
exercise.

The main one is to maintain blood glucose levels ready for when
they drop low.
During performance

These carbohydrates are broken down into glucose and may be
used before stored glycogen.

Fats can also be used before stored glycogen; this is called
glycogen sparing.

Finally, the blood glucose can be used to replenish glycogen stores
as they are performing.

A refuelling target of 30–60 grams of carbohydrate per hour of
activity is a good starting point when supplementing carbohydrates
during exercise.
During performance

Each of the following serves provides the equivalent of 60 grams of
carbohydrate:

1 litre sports drink
600 ml cola drink
1.5 sports bars
3 cereal bars
2 sports gels
3 small or 2 large bananas





During performance

Water is required by the body to give volume to blood, but most
importantly it maintains body temperature.

Heat is removed mainly by sweating and this rate will rise or drop
depending on the conditions in which the activity is conducted.

It is not only important to supplement any water loss during
competition as a result of the athlete sweating, but to also delay the
onset of fatigue and prevent dehydration occurring, which can affect
performance.

How much fluid and when drinks should be taken is purely up to the
individual.
During performance

Taking too much fluid can be counter-productive, as bloating and
increased urination will make it hard for the athlete to maintain
concentration.

The athlete should have a fluid plan, which involves weighing
themself before and after exercise and monitoring their sweat loss
during training, so that the performance is replicated and appropriate
amounts of water are consumed during performance.

An athlete should avoid caffeine and alcohol the day before and on
the day of competition.

Although water is the best replenishing fluid for an athlete, there are
also many other liquid options that athletes can take to maintain
peak performance.
During performance

Sports drinks are preferred by most athletes because of their taste.
Also, the added electrolytes in these drinks can assist endurance
athletes, as well as provide them with carbohydrates which water
doesn’t have.

The reason for this is the absorption rate in the contents of the drink.
If the drink has more than 8% carbohydrate in its content, then the
absorption rate will be slower for those drinks below 8%.

Sports drinks do more than plain water by having increased
electrolytes, particularly sodium which stimulates the absorption of
carbohydrates and water from the body’s small intestine, and
potassium which, helps with muscle fibre contraction.
During performance

The addition of sports drinks and added sodium will help to reduce
urine and fluid loss prior to and during competition and prevent
dehydration.

Athletes will start to fatigue when the energy supplies run out and
the stored energy becomes depleted.
Post-performance


After extensive performance glycogen levels in both the muscle and
liver are depleted.
For the athlete’s recovery and preparation for the next performance,
it is important that the body is returned to its normal state as soon as
possible.

It is recommended that the athlete intakes a high carbohydrate diet
within the first two hours of performance, as it will restore glycogen
levels in the body and start to repair tissue caused by the activity.

This is also the perfect time to try and replenish because the insulin
will rise quickly as a result of increased blood sugar levels and
maximise the storage of the glycogen.
Post-performance

In particular, high glycaemic foods will assist replenishment.

Fruit and vegetables such as watermelon and potato are also
important, as they carry extra nutrients, such as potassium and
other vitamins, needed for muscular contraction.

During recovery glycogen levels are restored, electrolytes are
rebalanced and tissues are repaired.

In the post-performance stage the muscle can restore its glycogen
content by about 5% per hour.

Athletes may hasten recovery by consuming at least 50 grams of
high or moderate glycaemic carbohydrates within the first 2 hours
when resynthesis of glycogen is highest.
Post-performance

If the exercise was strenuous and lasted a long time, glycogen
stores may need refuelling and resynthesis of glycogen can take up
to 24 hours. The total amount of carbohydrates ingested during this
time is important for recovery.

Protein is also needed after performance to help with tissue repair.
Some examples of carbohydrate and protein rich foods are:

1–2 sports bars (check labels for carbohydrate and protein content)

250–300 ml milk shake or fruit smoothie

250–300 ml liquid meal supplement.
Post-performance

If an athlete is 3 kilograms lighter at the end of a training session or
game, then they will need to

replace 1.5 times this amount and take on 4.5 litres of fluid to
rehydrate the body effectively.

Compare the dietary requirements for sports available on the AIS
website or the Sports Dietitians

Australia website:
www.ausport.gov.au/ais/nutrition/factsheets/sports/
www.sportsdietitians.com.au/fuellingfitnessforyoursport


Supplementation

A good diet will negate the need for supplementation of various
components of foods. Any dietary deficiencies can easily be fixed,
but this should be under the guidance of a sports nutritionist or a
doctor.
Vitamins/minerals

Some minerals are known as electrolytes which help in muscle
contraction and nerve transmission.

The major minerals for athletes include sodium, potassium, calcium,
magnesium, iron and chloride.

These minerals form salts that conduct electrical energy needed to
keep the body functioning and iron, which is also required to make
haemoglobin.

Calcium in particular is needed by the body for teeth and bone
formation.

As people age their bone density decreases and women especially
lose calcium from their bones which may cause osteoporosis.
Vitamins/minerals

To avoid osteoporosis, a high intake of dairy products when women
are young will help make stronger more dense bones.

If a person is allergic to dairy foods they may need to supplement
calcium. Minerals are just as important as vitamins and are also
necessary for growth, maintenance and repair of the body.

Vitamins in general are not made by the body, but are needed by the
body.

These vitamins are heavily involved in converting food into usable
forms of energy and help in chemical reactions.

Vitamins can be fat-soluble, stored in the body, and these are
vitamins A, D, E and K. However, if these vitamins are taken in
excess, they can lead to a poisonous imbalance in the body.
Vitamins/minerals

Water-soluble vitamins complex B and C need to be replenished
regularly as they can be passed out of the body through urine easily.

A good diet will maintain the required levels of vitamins, but if
excess vitamins are lost then supplementation may need to occur
particularly in the elderly and pregnant women.

Iron depletion is quite a common condition and is especially evident
in female athletes training continually at a high intensity. A result is
anaemia, which is a deficiency in red blood cells.

However, too much ingested iron can damage the cells of the
gastrointestinal tract. Any athlete exhibiting signs of lethargy could
indicate iron depletion.
Vitamins/minerals

As iron is a part of haemoglobin the ongoing effect is that the
oxygen uptake will decrease affecting performance.

Supplementation of iron should occur if there is a large blood loss,
such as through injury or menstruation, sweating heavily, an
inadequate diet or heavy training, which stimulates the number of
red blood cells and subsequent demand on iron in the body.


One of the major problems of iron deficiency is altering the athlete’s
diet if it is high in carbohydrates.
This is due to the difficulty to increase iron intake as the major foods
which have iron are also high in protein, which include red meat,
eggs, beans, broccoli and tuna. In this instance, iron supplements
may be more beneficial to the athlete.
Protein

Protein has an important role in the human body, as it is necessary
for building and repairing tissues.

It helps muscles contract and keeps the body healthy by resisting
diseases.

It is also seen as a minor energy source when both carbohydrates
and fats have been diminished.

Protein is regularly found in meat, fish, dairy products, breads and
cereals.

They are made up of amino acids of which the body makes a
majority of them, but requires supplements from food sources as
they are considered essential amino acids for bodily functions.
Protein

Amino acid supplements claim to make massive improvements,
such as reducing fatigue, increasing muscle size and improving
athletic recovery time.

There is no scientific evidence to prove that protein supplementation
will do any of these things. Moreover, they are expensive options
when a slight change in diet will cause the required change at a
cheaper cost.



If an athlete’s diet is poor, then protein powders will also provide
carbohydrates and may be a good solution to use for athletes under
the guidance of a sport’s dietitian.
A typical diet of an athlete will normally meet the body’s
requirements for protein even under heavy training.
Unlike carbohydrates, extra protein cannot be stored in the body and
any excess will be burned for energy or stored as body fat.
Caffeine

Caffeine is seen as an aid to performance.

It has the drug stimulant properties to increase concentration and
awareness.

This gives people a greater ability of concentration for 1–3 hours.

For athletes competing in sports where quick thinking and rapid
reactions are necessary, caffeine can provide an advantage.

One theory on caffeine is that it also has the ability to cause the
body to burn more fat and fewer carbohydrates.
Caffeine

Although glycogen is the major fuel used, fat is the most abundant
resource that the body uses for energy.

Caffeine enters the body and forces the working muscles to utilise
as much fat as possible. This delays the immediate depletion of
glycogen, such as glycogen sparing.

In 2004, the International Olympic Committee took caffeine off the
banned list of sports drugs.

Side effects of caffeine include muscle tightness, dehydration due to
its diuretic properties, nausea, lack of sleep and headaches. There
is new evidence to suggest that small or moderate intakes of
caffeine before, during and near the end of exercise have beneficial
effects on performance.
Creatine products

Creatine is a normal part of an everyday diet and combines with
phosphate groups to create phosphocreatine, which is used to
resynthesis ATP molecules.

Creatine is commonly found in meat, fish and chicken products and
is stored in skeletal muscle and as free creatine.

It gained notoriety after the 1992 Olympics where many 100-metre
athletes claimed that by supplementing with creatine they were able
to perform better.

A consequential study also found that by consuming large doses of
creatine over a number of days actually increased the storage in the
muscle and as such it was seen as being able to improve short-term
activities.
Creatine products

As a supplement the athlete can increase creatine load by taking
approximately 20–30 grams per day over a period of 5 days with
carbohydrates to maximise storage.

This loading process can increase the capacity for storage of up
25% and in some athletes as high as 50%.

This is of great importance for activities where phosphocreatine is
used, namely in sprinting and events where recovery time is
between 30 seconds and 3 minutes.

As a result of supplementation a single event may have a 1–3%
improvement, while repeated activities may have between 5–15%
improvement.

Sports that involve interval training or short bouts of speed, such as
soccer and touch football, may benefit from creatine
supplementation.

A side effect of this is weight gain, as creatine loading involves a
large storage of water The best type of supplement is creatine
monohydrate which, when taken with carbohydrates, enhances
quickly and is taken up well by the body.
Recovery strategies

Recovery is the time following a game or training session where the
body goes from being fatigued to being ready for the next
performance.

Active recovery is seen as better than passive recovery as it can
help remove lactate from the system. Overall, a good recovery
reduces fatigue and speeds up physical repair.

Coaches need to be aware of the athlete and how they feel when
training.

They may need to have longer recovery sessions if they present
with many of the factors outlined in Table 3.6.

Other forms of recovery available to coaches include cryotherapy,
hydrotherapy, relaxation techniques, massage, hydration and cool
down.
Physiological strategies, eg cool down,
hydration - Cool down

The cool down is the easiest and simplest form of recovery an
athlete can undertake.

It is very cost effective and occurs immediately after a performance.

It has been proven more effective in helping to dispose lactate out of
the body, which is extremely beneficial if an athlete has to return to
performance in a short period of time.

An example would be surfing ironman competitions where there is
only a 1 hour break between heats.

The cool down should be the reverse of the warm-up and consist of
active warm down to stretching.
Physiological strategies, eg cool down,
hydration - Cool down

This stretching will help restore the muscles to their previous length
and range of motion. It can also help decrease muscle tension and
relax the muscles.

Stretches can be held for 10 seconds and should be done in a warm
environment to aid the stretch. Stretching can form part of a
hydrotherapy recovery session and should consist of passive and
static stretches focusing on the joints used in performance.
Hydration

Fluids are an essential part of any athletic performance.

Athletes should monitor their fluid loss during exercise by weighing
themselves before and after performance and drink fluids after
performance to restore lost weight.

It is important that water volume is replaced through hydration on
the athlete’s behalf as well as electrolytes such as sodium, which
are lost through sweat.

These losses will vary from one athlete to the next.
Hydration

Alcohol should be avoided as part of a recovery plan because it
interferes with the athlete and the post-performance plan of eating
and the uptake of carbohydrates immediately following performance.

Alcohol can also lead to a dehydrating effect because it is a diuretic.

A good sports dietitian will monitor the athlete to regain estimated
fluid loss and identify the best possible fluid plan, for example,
whether the athlete needs electrolytes, carbohydrates or just water.
Neural strategies, eg hydrotherapy,
massage - Hydrotherapy

Deep water running with the aid of a buoyancy vest can be used by
athletes to maintain fitness after injury and decreases muscle
soreness or delayed onset of muscle soreness (DOMS) during
recovery sessions.

During this active recovery work the water provides buoyancy, which
allows the athlete to complete easy exercise with minimal impact on
the body.
Neural strategies, eg hydrotherapy,
massage - Hydrotherapy

Often after exercise the muscles have swelled in size due to
increased bloodflow and fluid carrying nutrients and oxygen to the
site.

The use of hydrotherapy will assist in reducing swelling to aid
recovery and future performance.

Using ice baths is gaining acceptance where the major stress in
sports competition is on the legs.

It involves an athlete standing waist deep in an ice bath of 2–10°C
for 1 minute, then standing out for 1 minute, and then repeating the
process 2–3 times.

This method is good for injuries where there is soreness or bruising.
Neural strategies, eg hydrotherapy,
massage - Hydrotherapy

The use of spas helps to relax the muscles and soft tissue injuries
and lowers the arousal level of the athlete which are both good for
recovery.

Contrasting hot and cold showers provides stimulation of the
nervous system and maintains arousal levels.

This involves 2 minutes in heated water, such as a spa, then a 1minute plunge into a cold environment, either ice bath or cold
shower, then repeat 4–5 times and finish with a cold part and
maintain hydration throughout.
Neural strategies, eg hydrotherapy,
massage - Hydrotherapy

Athletes need to stick to the guidelines for using hydrotherapy
techniques because if they stay too long the positive effects may be
affected and it could become a negative experience.

A spa is a good relaxation technique but should not exceed 15
minutes of use; if possible, the jets of a spa should be used for a
massage as well. Spas are not recommended for those with recent
bruising injuries.
Massage

Various research has indicated that massage has a beneficial effect
on reducing lactic acid levels in the body, which could be good for
athletes doing repetitive activities.

It has also shown to be a central role in the rehabilitation process by
returning the neural pathways to full working order as soon as
possible.

Massage is also a recommended technique to aid the recovery of
soft tissue injuries.
Massage

Tight muscles after competition will benefit from a massage, as it will
return the muscle to normal flexible positions prior to competition. If
muscles are not stretched, this poses injury problems for the next
performance as muscles will continue to be tight.

These tight muscles will also reduce blood flow to them and
therefore reduce oxygen and nutrients needed by muscles as part of
their recovery. If left unattended, tight muscles can eventually cause
postural deformities and lead to increased injuries, such as weak
abdominal muscles and strong back muscles.

Muscle tightness can place stress on the origin and insertion points
of the muscle. Massage can be used to realign muscle fibres, break
down scar tissue and decrease feelings of fatigue.
Massage

It is important for coaches or athletes to check through massage for
any abnormalities in the soft tissue as a result of injury.

By creating heat at the site and increasing blood flow, massage may
delay recovery from injury if used within 48 hours of a soft tissue
injury occurring.
Tissue damage strategies, eg
cryotherapy

Cryotherapy is the use of cooling as a means of treating injuries,
and may be used in different ways on both acute and chronic
injuries.

It is used extensively by athletes, as the vasoconstriction in the
blood vessels caused by a drop in temperature decreases the
amount of blood and scar tissue build up at the injured site.

This vasoconstriction limits oxygen flow to the site and decreases
the inflammatory response to the site.

Various methods of cyrotherapy include the RICE technique of rest,
ice, compression and elevation.
Tissue damage strategies, eg
cryotherapy

Do not apply ice directly to the skin but use a wet towel. It is
important not to keep the ice on any longer than 10 minutes as the
body then reacts by increasing blood flow to warm the area and
therefore increasing the swelling.

It is important for coaches to always check with the athlete when
using ice to establish their pain or sensitivity levels to it.

Ice massage is another form of cryotherapy used during recovery.

This consists of a block of ice approximately the size of a
polystyrene cup being rubbed over the surface.

This has the added benefits of cooling the site down, while helping
realign muscle fibres that may have been damaged, and
transporting lactic acid out of the working muscles fibres.
Psychological strategies, eg relaxation

Many different types of relaxation techniques can help an athlete
lower their arousal levels after performance.

While the arousal levels are high so too are bodily functions, such as
awareness, heart rate and blood pressure. Flotation tanks, which
contain heavily salinated water so that the athlete floats, can be
used for relaxation.

This lowers blood pressure, improves temperaments and decreases
the motor neuron responses to everyday stresses.
Psychological strategies, eg relaxation

Athletes can use soothing music to help put them in a relaxed state.
Good sleep is required too so that the athlete is alert and makes
good sound decisions. An athlete should get 7–9 hours sleep each
night and have at least 1 day of rest in their training calendar.

Warm baths, showers and meditation are all valid relaxation
techniques for athletes to use.

These techniques help the body rest to allow injuries or the body to
heal and replenish food and energy stores. Meditation is used
extensively as a focusing technique and this can lead to better
control of the nervous system and decrease heart and ventilation
rates, blood pressure and relax muscles.

Progressive muscle relaxation allows the athlete the opportunity to
apply tension and relaxation to certain muscle groups.