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core 2
factors
affecting
performance
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c h a p t e r
1
How does training affect performance?
energy systems
analyse each energy system by exploring:
Activities
1 and 2
– source of fuel
– efficiency of ATP production
– duration that the system can operate
– cause of fatigue
– by-products of energy production
– process and rate of recovery
The human body is an incredible machine which requires energy to do vast amounts of work to meet
the demands placed on it by everyday living. Energy is found in food, and the energy content of food is
measured in kilojoules. A person’s base metabolic rate (bmr) is the minimum amount of kilojoules the
body requires for it to function and stay alive; any extra activity will need extra energy.
Foods can be broken down into carbohydrates, fats and proteins. Each source of nutrient supplies a
different amount of kilojoules to the body:
• protein contains 17 kilojoules per gram
• fat contains 37 kilojoules per gram
• carbohydrate contains 16 kilojoules per gram.
The kilojoule content of foods depends on the amount of carbohydrates, fats and proteins present in
the food. Fat supplies around twice the kilojoules as the same amount of carbohydrate and protein, so it is
a longer lasting source of energy but it also takes longer to digest.
Carbohydrates
Carbohydrates are an ideal source of energy for the body, and are the main nutrient which fuel exercise of
a moderate to high intensity. They can be easily broken down into glucose, a form of sugar that is easily
used by the body. This breakdown into glucose is called glycolysis. Any glucose not needed immediately
gets stored in the muscles and the liver in the form of glycogen. Once these glycogen stores are filled up,
any extra gets stored as fat.
Carbohydrates can take the form of simple carbohydrates, such as sugars, or complex carbohydrates.
Natural sugars are found in fruit and vegetables and refined sugars are found in soft drinks, biscuits
and snack bars. Complex carbohydrates are starch-based foods and are available in root vegetables like
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factors affecting performance chapter 1
FOOD
Carbohydrates
Fats
Protein
Figure 1.1
DIGESTED FOOD
Glucose
Amino acids
Glycerol
Free fatty acids
ENERGY
FOR
ACTIVITY
Proteins, fats and
carbohydrates
are changed from
chemical energy to
mechanical energy
potatoes, wholemeal breads and in refined foods, such as white flour based foods like pizza and sugary
processed breakfast cereals.
Carbohydrates stored as glycogen are easily used for exercise. It normally supplies the energy for the
first few minutes of any activity, either as the main energy source or it may be needed to break down fats
for longer lasting sports. Athletes should always ensure they have full stores of carbohydrates prior to
competition.
Fats
Fats are the main energy source for long and low to moderate exercise, such as cycling. Fats are not used
initially when supplying energy, as oxygen is needed to break down fats; so it takes some time for fat to
be converted to energy. Foods high in fat stay in the stomach for a long period of time and as such can
become detrimental to performance if consumed too close to competition.
The major energy component from fats in the body is triglycerides, which aid to insulate the body.
Triglycerides need to be broken down, through a process called lipolysis, into glycerol and free fatty
acids to provide energy for activity. These free fatty acids are then broken down into glucose, which
requires oxygen. This process is also known as oxidation. When the body is digesting fats blood is needed,
which can cause cramping and discomfort when performing.
Most adults have enough stored fat in the form of adipose tissue to fuel activity for hours or even days
as long as there is sufficient oxygen to allow fat metabolism to occur.
Protein
Proteins are not normally used for energy, but will do so in extreme circumstances after all the fats and
carbohydrates have been exhausted. If protein was used as energy this would stress the kidneys because
they have to work harder to eliminate the by-products of this protein breakdown. Proteins are primarily
used for repairing and rebuilding muscle used during exercise. Strength athletes, such as weightlifters,
require more protein than endurance athletes, such as marathon runners, and the average adult due to
isolated muscle use. Proteins are broken down into amino acids.
How the body uses energy
By having a basic understanding of how food provides energy for athletes it is important to understand
how the energy is used by the body.
Food provides energy in the form of chemical energy, which must be converted to mechanical
energy. The breakdown of food produces energy that is stored in the body for later use. Adenosine
triphosphate (ATP). ATP is an energy-rich compound that the body uses to maintain the survival of
essential processes, such as heart beating and temperature regulation, as well as to meet the demands of
any exercise requirements. Energy for activity is stored in the muscles in the form of ATP. ATP is stored in
small amounts in the body, which is sufficient to provide energy for a short burst of muscular effort before
it fully breaks down. However, through a process of resynthesis the body has the ability to produce more
ATP to continue the exercise effort, depending on the type and length of activity.
The ATP molecule is made up of a large molecule called an adenosine molecule and three smaller
molecules called phosphates as seen in Figure 1.2
Figure 1.2
A molecule
Adenosine
P1
P2
P3
of adenosine
triphosphate (ATP)
Phosphate groups
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When the bond between phosphate 2 (P2) and phosphate 3 (P3) breaks it provides energy (Fig. 1.3),
which is then transferred to the cells and allows for movement to occur. The energy released allows muscle
cells to contract.
Figure 1.3
Adenosine
Adenosine
triphosphate
P1
P2
ENERGY
P3
is reduced to
adenosine
diphosphate (ADP)
or adenosine
monophosphate,
depending on how
many phosphate
groups break off
At this point the molecule has only two phosphate groups attached and is called adenosine
diphosphate and may also break down to a lower form of energy supply of adenosine monophosphate.
An average adult may break down or metabolise up to 40 kilograms of ATP per day to maintain bodily
functions. This can rise to 0.5 kilogram per minute during strenuous exercise. The breakdown of glycogen
and creatine phosphate (PC) will supply energy to resynthesise adenosine triphosphate (ATP) to provide
energy. Short-term energy supplies do not require oxygen to replenish ATP, so the ATP/PC
and lactic acid systems are called the anaerobic systems.
Fuel sources needed to provide ATP for longer duration activities will require oxygen to be present and
as such are called the aerobic energy system.
There are three energy pathways in which the body uses and replenishes ATP molecules to facilitate the
requirements of physical activity. The energy supplied is a combination of energy systems dependent on
the intensity and duration of the exercise, determining which method gets used and when.
The body cannot easily store ATP (and what is stored gets used up within a few seconds), so it is
necessary to continually create ATP during exercise. In general, the two main ways the body converts
nutrients to energy are aerobic and anaerobic energy systems.
Figure 1.4
Energy systems
ENERGY
Anaerobic
energy system
ATP/PC
Aerobic
energy system
Lactic acid
– alactacid system (ATP/PC)
The alactacid system (ATP/PC) uses the stored ATP molecules in the muscle, usually for a few seconds or
one explosive movement. The ATP molecule is then unable to provide energy to the working muscles. To
continue the muscular movement, the body now relies on creatine phosphate (PC) in a secondary reaction
(see Fig. 1.5).
The creatine phosphate separates into two molecules of creatine and phosphate. The energy derived
from this reaction is enough to rejoin or resynthesise the floating phosphate groups. The body is not using
new ATP molecules but rather resynthesising the ones that had previously been broken down. This system
is used for short bouts of exercise, especially those lasting for only up to 12 seconds, such as 100-metre
sprint, shotput and discus.
– source of fuel
This process of resynthesis of ATP goes on continually until the creatine phosphate molecules are broken
down, which normally takes between 10–12 seconds. Creatine phosphate thus provides the fuel for the
alactacid energy system.
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factors affecting performance chapter 1
1
Adenosine
P1
P2
Figure 1.5
P3
Alactacid energy
system
Adenosine triphosphate molecule
2
Adenosine
P1
P2
ENERGY
P3
The bonds between phosphate groups 3 and 2 break giving off energy for muscular
contractions. P3 is now a floating phosphate group
3
Adenosine
P1
P2
ENERGY
P3
A further split between phosphate groups 2 and 1 creates more energy
4
Creatine
ENERGY
Phosphate
A secondary reaction occurs when the creatine phosphate molecule splits, giving off energy.
This energy will be used to resynthesise (or rejoin) P2 and P3 with the adenosine molecule to
form ATP.
5
Steps 1–4 are repeated until the supplies of PC are fully used
– efficiency of ATP production
This is an efficient form of energy production as the chemical reactions occur very quickly and are
very simple. The fuel for this system is already stored in the muscle as is the ATP molecule. It allows
for immediate production or resynthesis of ATP molecules and as such does not rely on oxygen to
resynthesise ATP molecules.
The recovery time for this system is also very short. The creatine phosphate molecules will replenish
themselves completely if the body is at rest for a minimum of two minutes (approximately 50% of PC
will be restored in the first 30 seconds of rest).
Without the ATP/PC system, fast, powerful movements could not be performed, as these activities
demand a rapidly available supply of energy. For each molecule of PC there is one molecule of ATP
resynthesised.
– duration that the system can operate
In this system, ATP is only stored in the muscles for 1–2 seconds of activity. Creatine phosphate (PC)
molecules are also stored in the muscle and will last for a further 10–12 seconds. This means that the total
duration for this energy system is approximately 10–12 seconds.
– cause of fatigue
Fatigue in the ATP/PC system is mainly due to the inability of the body to continually resynthesise ATP
molecules. This occurs when the body has used up all of its stored supply of PC.
– by-products of energy production
The only by-product given off in this energy system is heat, as a result of the reactions breaking phosphate
groups off PC and ATP.
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–
process and rate of recovery
The rate of recovery is relatively short from activity. After full
depletion of ATP and PC the body will take approximately
two minutes to fully regain its normal levels of PC.
–
Figure 1.6
A shot putter uses
the alactacid system
lactic acid system
If muscular contraction is continually required beyond
the limit of the alactacid system, the lactic acid system will
continue providing the ATP molecules to create required
energy.
This system produces lactic acid as a waste product in
the chemical breakdown of glucose and glycogen (called
glycolysis). After the lactic acid system has used all of the
PC, the body needs to find a new fuel in the form of
blood glucose or glycogen stored in the muscle to keep
going.
Anaerobic glycolysis provides energy by the partial
breakdown of glucose without the need for oxygen. As
glycolysis occurs the glucose is broken down into pyruvic
acid, but due to a lack of oxygen it then transforms to lactic acid. This lactic acid then builds up in the cell
and is transferred into the blood stream where the body tries to get rid of it.
– source of fuel
The major source of fuel for this system is carbohydrates in the form of sugar travelling in the
bloodstream, known as blood glucose, and the glycogen stored in the muscles, known as muscle glycogen.
– efficiency of ATP production
This is a very efficient system as it continues to resynthesise ATP molecules after the ATP/PC system has
ceased. The breakdown of glucose and glycogen provides energy which will result in the resynthesis or
regeneration of ATP molecules to be used for muscular contraction in a short time.
– duration that the system can operate
Anaerobic metabolism produces energy for short, high-intensity bursts of activity lasting approximately
one minute at high intensity or up to three minutes for moderate intensity. If intensity is sub-maximal,
then this energy system can last longer than three minutes.
– cause of fatigue
It was formerly thought that lactic acid was the major cause of fatigue when using this system. Lactic acid
is produced as a by-product of this system and has to be transported out of the body’s cells by the blood. If
high-intensity exercise is maintained for quite a long time (40–60 seconds) the blood cannot transport all
the lactic acid out of the system and so it builds up.
This is where the onset of blood lactate accumulation (OBLA) occurs and causes the muscles
to fatigue. This is also known as the lactic acid threshold or anaerobic threshold. At this point the
athlete’s performance decreases as does intensity and muscles start to tire and performance is affected.
This is clearly evident at the end of a 400-metre race where an athlete appears to be running quicker
than other athletes, but in fact the other athletes are slowing down faster due to lactic acid build up.
When lactate was produced in the absence of oxygen, hydrogen ions were also produced. The
presence of hydrogen ions, not lactate, makes the muscle acidic as they alter the pH component of the
cell and that will eventually halt muscle function. As hydrogen ion (H+) concentrations increase, the
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factors affecting performance chapter 1
blood and muscle become acidic. The higher
than normal acid content in the cell will alter
the breakdown of glucose. Acidic muscles will
aggravate associated nerve endings causing
pain and increase irritation of the central
nervous system. When the acid content of the
cell increases, nerve endings are stimulated
and the perception of burning is encountered
by the athlete. Fatigue is due to the increased
hydrogen ion concentration and not the lactic
acid.
– by-products of energy production
The by-product of the lactic acid system is
pyruvic acid which, in the absence of oxygen,
produces lactate and hydrogen ions (H+). The
lactate is then used by the cells, of which 65%
is converted to carbon dioxide and water, 20%
into glycogen, 10% into protein, and 5% into
glucose.
– process and rate of recovery
It takes 20 minutes to 2 hours for lactic acid to be removed from the blood. Depending on the body’s
needs at a particular time, lactic acid is also capable of being converted into glycogen. The body’s recovery
from using this system will be enhanced if an active cool down is completed; this will aid the transfer of
lactic acid around the body where it can be reused. However, the active cool down should be below the
effort that would produce more lactic acid, for example, 40–50% of maximum heart rate.
Figure 1.7
Cathy Freeman won
the Sydney Olympics
400 metres final in
2000, pulling further
and further into the
lead in the
last 50 metres
of the race
– aerobic system
The aerobic system requires oxygen to make the ATP molecules needed for exercise. Aerobic exercise
is known as steady state exercise, because the energy demands meet the energy being supplied by the
body. As the oxygen is transferred around the body via the circulatory system, it eventually reaches
the working muscles. As the body reaches its anaerobic threshold, the body starts to slow down and
the oxygen has time to reach the working muscles and change pyruvic acid into carbon dioxide,
water and ATP. As a result, no more lactic acid is produced due to the presence of oxygen.
Aerobic glycolysis occurs when oxygen (O2) is available to break down pyruvate, which produces ATP
through chemical reactions that occur in the Krebs Cycle and the ‘electron transport system’. The body
now starts to break down glucose and fats, as well as convert pyruvic acid so it can be used to regenerate
ATP using oxygen.
To begin the long-winded process of creating ATP molecules via the aerobic energy system the glycerol
portion of fat as well as pyruvic acid are converted to acetyl coenzyme A (Acetyl CoA), which is necessary
for the next step in creating energy. The free fatty acids are also converted to acetyl co enzyme through a
different process, called beta oxidation.
At this point both the glycerol and the fatty acids have been converted to Acetyl CoA and are now ready
for the Krebs Cycle to take place in the cells of the mitochondria. As the Acetyl CoA is broken down,
carbon dioxide and hydrogen are removed. The energy from the breakdown of this is used to regenerate ATP.
Once again the carbon dioxide exits the body through the lungs. However, the hydrogen moves on to
the final stage of the electron transport system where it combines with oxygen to form water (H2O).
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Figure 1.8
Muscle and
liver glycogen
Overview of the
aerobic energy
system
Aerobic Energy System
Fat
Pyruvic acid
Triglyceride
With O2
Free fatty
acids
Without O2
Glycerol
Lactic acid
Acetyl CoA
Lactate
Krebs
cycle
CO2 exhaled
H+
ATP produced
from the electron transport system
Combines with O2
and forms sweat
H+
ATP produced
– source of fuel
The fuel for the aerobic system is primarily glucose and free fatty acids. Most humans have fats available to
be used and so have a limitless supply of fuel to keep creating ATP molecules, these fats are broken down
into glycerol and free fatty acids. This is essential in changing the structure of fat so it can be broken down
in the presence of oxygen.
– efficiency of ATP production
For longer slower duration of exercise, the aerobic system is very efficient in being able to provide an
endless supply of energy to resynthesise ATP for an extended period of time. Compared to glucose, fats
can supply up to 10 times as many ATP molecules.
– duration that the system can operate
The aerobic energy system can supply energy to the body from 2–3 minutes to a few hours. However, it is
used primarily during endurance exercise, which is generally less intense and can continue for long periods
of time. If a person is exercising at a low intensity (that is, below 50% of maximum heart rate), their
body has enough stored fat to provide energy for hours or even days, provided there is enough oxygen for
reactions to occur. Obviously the higher the intensity of the exercise, it will be easier to become exhausted
because all of the supplies in the body will be used up. The aerobic system is the same system the body
predominantly uses to maintain its everyday bodily functions.
– cause of fatigue
The main cause of fatigue in this system is due to the depletion of glucose to the working muscles. Poor
respiration or circulation where it is difficult for oxygen and nutrients to get to working muscles and
subsequent poor removal of waste products can also lead to fatigue.
– by-products of energy production
The by-products formed from using this system are carbon dioxide (CO2) and water (H2O), as a result of
chemical reactions. The water is lost through sweat or expiration and is also made available to other cells
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factors affecting performance chapter 1
Figure 1.9
% of maximum rate of energy production
ATP store
ATP-PC system
Lactic acid system
Overall performance
Aerobic system
T = Threshold point
T
2 sec
10 sec
T 1 min
2 hrs
Contribution of
energy systems to
activity in terms
of time
time
Source: Adapted from Brianmac Sports Coach www.brianmac.co.uk
in the body. The carbon dioxide is breathed out as exercise takes place. These by-products are not harmful
to the athletic performance.
– process and rate of recovery
The rate of recovery is dependent on the type of activity that has taken place. High-intensity activity for
an extended period of time will take a longer time for recovery, than if the activity was low intensity. The
main factor to be aware of is to replenish lost glucose and glycogen, which could take days for the food to
be fully digested.
Note that the time taken for oxygen to reach the working muscles is between 2–4 minutes before ATP
is supplied predominantly by the aerobic system.
Pathways of energy systems
During exercise an athlete will move through the various energy pathways. As exercise begins, ATP is
produced through anaerobic metabolism from both the ATP/PC system and the lactic acid system. With
an increase in breathing and heart rate, there is more oxygen available and aerobic metabolism begins and
continues to resynthesise ATP molecules over an extended period of time.
The energy systems do not work independently of each other but rather have some contribution to all
sports as seen from Figure 1.11. The amount of contribution depends on the intensity of the activity, the
duration of the activity and how explosive the activity is.
Figure 1.10
Duration of
maximal
exercise
%
Anaerobic
1–3 sec
100
0
10 sec
90
10
energy (ATP) versus
30 sec
80
20
time
1 min
70
30
2 min
60
40
4 min
35
65
10 min
15
85
30 min
5
95
1 hour
2
98
2 hour
1
99
%
Aerobic
Proportion of
aerobic/anaerobic
production of
sources: brooks, g., fahey, t., white, t., 1996. exercise physiology. human bioenergetics and its applications and mole, p., 1983. exercise
metabolism in exercise medicine: physiological principles and clinical application
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Figure 1.11
Energy systems for
selected sports
ATP-PC
Lactic acid
Aerobic
Sport/activity
ATP-PC
Lactic acid
Aerobic
Baseball
80
15
5
Basketball
80
10
10
Field hockey
60
20
20
90
10
0
Golf (swing)
100
0
0
Gymnastics
90
10
0
Ice hockey
80
20
0
Rowing
20
30
50
Soccer
60
20
20
Diving
98
2
0
Swim (50 m)
95
5
0
Swim (100m)
80
20
0
Swim (200 m)
30
65
5
Swim (400 m)
20
40
40
Swim (1.5 km)
10
20
70
Tennis
70
20
10
Field events
90
10
0
Run 400 m
40
55
5
Run 800 m
10
66
30
Run 1.5 km
5
35
60
Run 5 km
2
28
70
Marathon
0
2
98
Volleyball
90
10
0
Wrestling
45
55
0
Football
Source: Fox, E.L, Mathews, D.K, 1974. Interval training: conditioning for sports and general fitness, Saunders College Publishing, Orlando, Florida.
Figure 1.12
Tennis is 70%
ATP/PC, 20%
Lactic Acid and
10% aerobic
energy system
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factors affecting performance chapter 1
types of training and training methods
assess the relevance of the types of training and training methods for a
variety of sports by asking questions such as:
Activities
3–7
– which types of training are best suited to different sports?
– which training method(s) would be most appropriate? Why?
– how would this training affect performance?
The type of training undertaken by an athlete should meet the specific needs of the activity being trained
for. The three main types of training are strength, aerobic and flexibility training.
– aerobic, eg continuous, Fartlek, aerobic interval, circuit
The main objective of aerobic training is to make the athlete’s body more efficient at using oxygen. This
involves training the larger muscle groups—the arms, chest and legs—to efficiently combine with the
cardiovascular system to supply oxygen to the athlete and their working muscles.
Any training that will build cardiorespiratory endurance is termed aerobic training when the majority
of the energy in the athlete is derived aerobically. Aerobic training should follow the FITT principle,
which is at least three times a week for 20 minutes and between 65–85% maximum heart rate. There are
many different types of aerobic training, such as continuous, Fartlek, aerobic, interval and circuit. Some
are listed in Table 1.1 with suggested training sessions.
T y pe
Continuous
Frequency
D u r at i o n
( pe r w ee k )
( pe r s e s s i o n )
1–2
Fartlek
1
Interval
1–2
Race distance or longer (or
30–120 minutes)
20–60 minutes
3–5 minute interval
(work–rest ratio of 1:1)
ta b le 1 . 1
Types of aerobic
endurance training
Intensity
Approximately 70% VO2
Variable –70% VO2 max with
bouts at or above lactate
threshold
Near VO2 max
Source: www.sport-fitness-advisor.com/aerobic-endurance-training.html, as adapted from Essentials of Strength Training and Conditioning (2000) (8)
Continuous training
This is the simplest form of aerobic training where there is no rest, but rather continual effort and at an
intensity where the heart rate will be in the aerobic training zone for at least 20 minutes. Some examples
include jogging, swimming or cycling. This training can vary from long slow duration of between 60–
80% maximum heart rate aimed at aerobic endurance, to higher intensities of approximately 80–90%
maximum heart rate, which will train the body’s ability to deal with lactic acid for long periods of time
and possibly increase the OBLA. If there is too much continuous training an athlete would run the risk of
overuse injuries.
Fartlek training
Fartlek training involves alternating bursts of high-intensity activity while still maintaining the longer
slower style of training. This training is less structured than interval training with no predetermined
structure to follow. The athlete can then concentrate on feeling the pace and their physical response to it,
so that they’re able to develop self-awareness and pace judgment skills to set their own pace.
Work–rest intervals can be based on how the body feels. Beginners tend to enjoy Fartlek training
because it is more flexible and can be done on all types of terrains, not specifically just on a track. This is a
good form of training for the aerobic energy system.
The athlete runs continuously and puts in some sections of higher intensity or slightly higher pace. For
example, an athlete may run at their normal pace for 300 m, then harder for the next 100 m; they then
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slow down for 300 m until breathing is back to normal
levels, and then repeat the higher intensity burst for
100 m. By doing this, an athlete is placing more stress on
their system, which the body will adapt to after time and
will improve their speed and anaerobic threshold.
Interval training
Figure 1.13
Running is a great
way to train for
interval and Fartlek
training
Interval training involves periods of structured work
interspersed with rest periods in a set pattern that are
designed to match the athlete’s sport and conditioning
levels. This enables the athlete to perform at a higher
intensity than if they were continuously training. It also
minimises the chances of overuse injuries by allowing rest.
This lets the athlete be progressively overloaded and allows
the body time to adapt to changes before the interval
program is changed slightly.
This type of training program has great scope for variety
due to the variables that can be changed, such as frequency, intensity and duration. Altering any of these
can help the athlete avoid fatigue, maintain variety and be motivated.
An interval session could be running 200 m in 35 seconds with a 60-second recovery period. A second
session could be running 200 m in 35 seconds with a 30-second recovery period. In this way the athlete is
training both the aerobic and anaerobic energy system, in the first instance with a longer recovery session,
but in the second instance mainly the anaerobic energy system.
Due to these factors interval training is seen as a great way to improve both the aerobic and anaerobic
systems due to its structure. This allows the body to build new capillaries and become more efficient in the
delivery of oxygen to the working muscles.
Circuit training
ta b le 1 . 2
Sample circuit class
outline
Circuit training is a type of interval training as it relates to the athlete selecting different exercises or
stations to use for a set interval of time with little or no rest. The number of circuits and stations can be
predetermined by the coach or the athlete, and can consist of set machines or body weights.
Circuits can be customised from beginners to more experienced athletes to develop all-round fitness.
A well-designed circuit provides a balanced workout that targets all the muscle groups to effectively
develop strength, build cardiovascular endurance (both aerobic and anaerobic), and allow flexibility and
coordination all in one exercise session.
Circuit training can progressively overload the athlete by altering the exercise time at a given station,
increase resistance, and add more exercises for a certain area of training and decreasing rest time between
stations.
Exercise
Circuits
Wee k
Work
Re s t
Number
Re s t
1
2
3
4
5
6
7
8
20 sec
30 sec
40 sec
20 sec
30 sec
30 sec
40 sec
30 sec
20 sec
30 sec
40 sec
20 sec
30 sec
30 sec
40 sec
30 sec
2
2
2
3
3
4
3
3
2 min
2 min
3 min
2 min
2 min
2 min
3 min
2 min
Source: www.brianmac.co.uk/circuit.htm
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factors affecting performance chapter 1
Figure 1.14
1
10
Sit ups
Bent-knee sit-ups with
hands on side of head.
8
Squats
Repeated squats.
Resistance may be
increased by
holding weights.
Burpee
Squat down, take weight onto
hands, perform a squat thrust,
return to squat, weight onto
legs and jump up.
Seated dips
Sit with hands on edge of
bench, legs extended in front.
Allow body to descend to floor
and then press up. Higher
bench increases resistance.
2
Press ups
Either narrow arm or wide
arm. Easier if knees in
contact with ground, harder
if feet on bench.
Bent arm pullovers
Lie on back on bench. Dumbbell
held in two hands, taken back
behind the head and returned
to in front of head.
7
class of ten exercises
Step ups
Step up and off
the bench. Weights
may be used.
Straddle jumps
Use bench. Step up onto and
off bench, from the side using
alternate legs. Slow movements
are easier, rapid movements harder.
9
Example of circuit
Shuttle runs
Run around outside
of working area.
6
3
4
5
Dorsal press
Lie on front on mat. Use arms
to hyperextend back and then
lower trunk back to lying position.
Figure 1.15
Walking is a great,
low-stress way to
Source: www.brianmac.co.uk/circuit.htm
exercise
– anaerobic, eg anaerobic interval
Anaerobic interval training is similar to aerobic interval training
in that high-intensity activity is completed with either lesser
recovery or at a minimum of 2 minutes rest applied. With such
a minimal recovery an athlete will train as close as possible to the
anaerobic threshold, so that they can try and increase the tolerance
to lactic acid and use the anaerobic energy system more efficiently
for endurance. By using a minimum two minutes rest it gives the
creatine phosphate time to replenish and allow for full explosive
activity to occur again. This is an exceptional training method for
experienced athletes who predominantly use the ATP/PC or lactic
acid systems for events such as 400- to 1500-metre running.
The advantages for using this type of training include muscles
developing a higher tolerance to the build-up of lactate and
an improved performance by increasing the efficiency of the
cardiovascular system.
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– flexibility, eg static, ballistic, PNF, dynamic
Flexibility refers to the range of motion of a joint or group of joints. There are a number of ways in which
flexibility can be utilised, including static stretching, proprioceptive neuromuscular facilitation (PNF),
dynamic stretching and ballistic stretching—first two involve passive stretching and the last two involve
movement.
The degree of flexibility of motion varies among people and depends on the structural characteristics
of their joint and its connective tissue. Flexibility decreases with age primarily due to loss of elasticity
and joint mobility. Generally, females are more flexible than males. A flexible person will have improved
neuromuscular pathways, which will minimise injuries. Temperature also influences flexibility, as an
increased range of motion is available in warmer temperatures.
When a muscle is stretched, receptors within the muscle, known as muscle spindles are stimulated. They
record the change in length and send a signal to the spine, which then sends a message to the brain that the
muscle is being extended. If the muscle is overstretched or stretched too fast, the spinal cord sends a reflex
message to the muscle to contract. This is a basic protective mechanism, referred to as the stretch reflex, to
help prevent over-stretching and injury. A reason for holding the stretch is so the muscle spindle adapts and
gets used to the length of the stretched muscle and ceases to send signals to the spinal cord and brain.
Each of the following stretching methods operates on the idea that to increase flexibility and prevent
risk of injury, the muscle being stretched should be as relaxed as possible.
Static stretching
This is a form of passive stretching and consists of stretching a muscle to its farthest point or limit and
then maintaining or holding that position for a period of 15–30 seconds. This is the most commonly used
flexibility technique and is very safe and effective, because it is done in a controlled slow manner. Static
stretching is used extensively with athletes recovering from injury to ensure that the muscle fibres are being
aligned properly in the rehabilitation phase. This stretch should be performed without discomfort or pain.
PNF stretching
The PNF (proprioceptive neuromuscular facilitation) method is a combined technique of static stretching
and isometric stretching and works with the muscle spindle to get used to the new length of the muscle.
A muscle group is statically stretched, and then contracts isometrically against resistance while in the
stretched position. It is then statically stretched again through the resulting increased range of motion.
PNF stretching usually requires the use of a partner to provide resistance against the isometric contraction;
the static stretch will help the muscle spindle get used to the new length of the muscle after it has been
isometrically stretched.
Figure 1.16
Motor neurons to activate
muscle fibres to resist pull
The stretch reflex
Pull on length of muscle
from forward instability
Your intended activity
Nerves from central nervous system
to change sensitivity of spindle
Stretch on receptor in the muscle spindle
98
factors affecting performance chapter 1
(a)
(b)
(c)
Figure 1.17
PNF stretching is an excellent method of stretching for rehabilitation as it can stretch further than
static stretching in a controlled environment with minimal risk of injury.
Dynamic stretching
Hamstring stretches
(a) PNF stretch
(b) PNF contraction
(c) static stretch
This method involves actively moving parts of the body being stretched to increase the length of the
muscle. It is a controlled movement, which takes the muscle to its limits where it is guided by the stretch
reflex on how far to stretch. Dynamic stretching does not force the muscle beyond its normal range of
motion. An example would be swinging a golf club just prior to a shot being played.
Ballistic stretching
Ballistic stretching is a form of dynamic stretching and uses the movement of the body to force it
further than its normal range of motion. This is stretching by bouncing into a stretched position, using
the stretched muscles as a spring which pulls you out of the stretched position. An example would be
toe touches to stretch hamstrings by bouncing down and touching the toes with your hands.
The main problem with this type of training is that the stretch can actually override the stretch reflex
mechanism and cause injury. So this type of stretching is not useful for beginners or intermediate athletes,
because it does not allow the muscles to relax in the stretched position. However, for elite athletes trained
in this method of stretching, it very useful because it replicates movement required for their specific
activity better than other methods.
– strength training, eg free/fixed weights, elastic, hydraulic
Strength or resistance training is another training method used to improve athletic performance. Strength is the
maximum force against a set resistance that muscles can exert in a single effort. This force is related to the crosssectional area of the muscle fibre and subsequent muscle itself, for example, the bigger the muscle the bigger the
force given. This is a basic definition of absolute strength, however, there are other strength training methods,
such as power and endurance, all of which have different programs that athletes use to achieve their goals.
All sports use at least one form of strength or resistance training. In order to have a better
understanding of strength it is important to understand the following terminologies that are specific to
resistance training:
• repetition: The number of times an exercise is repeated without a break.
• repetition maximum (RM): The amount of resistance you can lift 1 time. For example, 12 RM is the
maximum weight you can lift 12 times.
• set: The number of repetitions completed make a set. For example, 8 RM = 1 set; 8 RM done 3 times is
3 sets and is 24 RM total.
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PDHPE in focus hsc course
•
•
•
•
•
•
•
rest: The period of time you allow for the body and muscles to recover between sets.
resistance: Another word for weight.
endurance: The ability for a muscle to repeatedly contract against a given resistance and reduce fatigue.
power: The ability for the muscle to exert force over a distance in a short time.
spotter: A partner who helps with an athlete’s exercises.
eccentric contraction: Lengthening of the muscle fibres.
concentric contraction: Shortening of the muscle fibres.
Muscles will contract in different ways depending on the type of training and the method used.
A muscle will either shorten or lengthen when undergoing a resistance program. Types of muscular
actions are:
• isometric: A force is applied but there is little or no change in length of the muscle and its fibres. The
strength is specific to certain angles.
• isotonic: Muscle fibres shorten or lengthen depending on the exercise and whether it is the agonist
or antagonist muscle in the exercise. For example, in biceps curl, the biceps shortens in a concentric
contraction while the triceps lengthens in an eccentric contraction.
• isokinetic: The use of machines to ensure the weight is applied through the full range of motion. These
machines are elaborate in their design to ensure exercise is done correctly.
When a coach trains an athlete they take into account what physical activity the athlete will be doing,
the specific type of strength required and the muscle fibres that will be used to do it. The coach should
know the predominant types of muscular activity associated with the physical event, the movement
pattern involved and the type of strength required.
Most strength programs will require a recovery of 3–5 minutes between sets to enable the ATP/PC
system to replenish the PC component and for the fibres to recover somewhat (however, only minimum
recovery should be taken if strength endurance is the aim). The majority of athletic events are fast and
dynamic so this specific requirement must be present in any program.
There is also a variety of equipment available to increase strength.
Suggested guidelines for repetition maximum (RM) in strength training
programs
1 to 3 RM: neuromuscular strength
4 to 6 RM: maximum strength by stimulating muscle hypertrophy
6 to 12 RM: muscle size (hypertrophy) with moderate gains in strength
12 to 20 RM: muscle size and endurance
Source: www.brianmac.co.uk/weight.htm
ta b le 1 . 3
Types of strength
training programs
T y pe o f s t r e n g t h
r e s i s ta n c e
r epe t i t i o n s
sets
training program
Absolute
Power
Endurance
Re s t
Sp o r t s p r o g r a m i s
3–5
minutes
2–3
minutes
power lifting, Olympic lifting,
shot put
power-based events, such as
sprinting, jumping (long jump),
throwing (javelin)
appropriate for field sports,
rowing and martial arts
s peed
80–00% of
1RM
70–80% of
1RM
30–50% of
1RM
1–5
3–6
fast
6–10
3–6
fast
+15
3–6
medium
Source: Adapted from www.brianmac.co.uk/weight.htm
100
Exercise
good for
1–3
minutes
factors affecting performance chapter 1
Weight machines
Weight machines enable correct positioning and
proper movement while an athlete is lifting weights.
Most machines are hydraulic in nature and are
excellent for isolating individual muscles. The
guided action and variable resistance when training
also make weight machines popular as rehabilitation
instruments, as they are much safer than free
weights or dumbbells. The weight in the machine
will only move if the athlete applies force to it
increasing safety for the user.
Weight machines are very expensive and are
not space efficient. Variable resistance machines
are effective tools for building strength and muscle
tone and are designed to work the target muscle in
isolation. However, this prevents the athlete from
recruiting other muscle groups when performing
exercise which the free weights do.
Free/fixed weights
Figure 1.18
Machine weights
versus free weights
Dumbbells and barbells can appear as either fixed or free weights. Some free weights are fixed at set
weights and some are adjustable. Free weights allow a greater range of motion than machines and allow
for symmetry to occur between both sides of the body when doing resistance training. Using free or fixed
weights also encourage better joint strength and a closer transfer of training to a given activity.
Free weights can isolate a particular muscle and enlist the help of the antagonist muscle at the same
time. The assisting muscles help stabilise the body, support limbs and maintain posture during a lift.
Lifting free weights improves the athlete’s coordination by making the neuromuscular pathways better.
Free weights are cheaper than fixed weights because they can be adapted for a number of exercises;
whereas fixed weights requires the athlete to have several different weight sizes available to alter the
resistance during strength training and not to overload the body. In terms of safety it is recommended that
when people use free or fixed weights they work with a spotter.
Elastic bands
A more recent form of resistance training is the use of elastic bands. These are a cheap alternative to
weights and provide much the same resistance. They are extremely space effective and different elastics
are available with different resistance (they are
normally colour coded). The use of elastic bands
also offers variety where athletes can continue their
training program with a different method.
One of the main advantages for using elastic
bands is that the athlete feels the resistance during
the full exercise motion. For example, when using
dumbbell weights, the resistance is stronger when
performing the up motion, like in the bicep curl.
But on the down motion, the resistance is less as
gravity is helping with the return position. With
resistance bands, the muscle tension is felt at both
the up and down and full range of motion, giving
the athlete complete resistance training.
Figure 1.19
Elastic bands are
a cheaper form of
resistance training
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Activities
8–11
Sample
student
answer
principles of training
analyse how the principles of training can be applied to both aerobic and
resistance training
There are various principles of training that athletes must take into account if they are going to maximise
their training and have a successful performance. By adhering to the following principles the athlete will
be physically and psychologically prepared for their event.
– progressive overload
One of the key principles of training is progressive overload. Improvement will only occur when the
athlete undertakes a training load exceeding what the body is normally accustomed to and is forced to
operate beyond its normal range.
Progressive overload can be achieved by varying the frequency, duration and intensity of the training.
Changes in intensity have the greatest effect on fitness. However, it can cause injury if done incorrectly.
To avoid this, the athlete should first alter the frequency, then increase the duration and then increase the
intensity when the fitness level is high enough to cope with the extra demand.
Overload can be progressed in resistance training by increasing: the resistance, the number of
repetitions with a particular weight, the number of sets, the intensity—more work in the same time by
reducing the recovery periods.
Overload can be progressed in aerobic training by increasing: the time spent exercising, the frequency of
training, the intensity—to cover a set distance in slightly less time.
An athlete will need appropriate recovery time between sessions. Once the body has adapted to a
certain level, increase the load and repeat training. This initial training program will produce a training
response.
Adaptation occurs during the recovery period after the training session is completed. If there is
no progression, then the athlete’s fitness level will plateau and no improvement will occur. Workloads
which are too high, and have abrupt increases in frequency, duration, or intensity, can lead to overuse
injuries.
Athletes must be careful to maintain a balance in their training program. If they overtrain, this will
be detrimental to their performance, and if the training is not overloaded enough improvement will not
occur.
Athletes need to be aware that not all adaptations will occur in the same timeframe. Improvement
should be noted for any sport after at least six weeks work. The key to successful training is to increase
the workload gradually over a long period so that improvements can be maintained and overtraining
avoided.
– specificity
ta b le 1 . 4
Sample of a
progressive
overload resistance
and aerobic
Specificity is exercise aimed at specific or designated components of fitness, muscle groups and/or energy
systems used in the activity being trained for. Specificity should also be used to replicate as closely as
possible the movements in the activity being trained for.
For example, a cyclist will not get much benefit from swimming due to different muscle groups, but a
squash player may get more benefit from playing tennis although the technique is slightly different. The
program
1 and 2
3 and 4
5 and 6
7 and 8
3 sessions
4 sessions
4 sessions
4 sessions
pe r w ee k
pe r w ee k
pe r w ee k
pe r w ee k
Resistance training /
reps and sets
2 sets  5 reps
60% RM
3 sets  5 reps
65% RM
3 sets  8 reps
60% RM
3 sets  8 reps
65% RM
Continuous
training /reps and sets
Run 5 km at 70%
max HR
Run 5 km at 70%
max HR
Run 6 km at 70%
max HR
Run 6 km at 75%
max HR
Wee k
102
factors affecting performance chapter 1
squash player gets more transfer from their training by playing tennis. This will
then overload the relevant physiological systems and achieve a training effect
for the squash player and follow the principle of specificity. If training closely
resembles what the actual performance is then positive athletic gains will be
made.
– reversibility
If training is stopped, gains made by the athlete will decline at approximately
one-third of the rate of acquisition. Athletes should maintain strength,
conditioning and flexibility throughout the competitive season, but at a lesser
intensity and volume. This is also called detraining as the training is going in
reverse.
A study of an Olympic rower in the United Kingdom found that after
8 weeks of rest it took the same athlete 20 weeks to achieve the level of fitness
they had prior to the rest. After 8 weeks of training previous fitness levels had
returned to about 50 % of their normal level.
As a result of the study, researchers suggest that complete rest last for no
more than 2–3 weeks, and that recommended training programs should limit
periods of complete inactivity to no more than
2–3 weeks. Extended periods of rest should be avoided if performance is to be maintained.
It is certainly difficult to maintain training if the athlete is injured, but substitute training should
occur for the athlete to try and maintain previous levels of strength, flexibility or aerobic fitness prior to
the injury. This will reduce the detraining effect and allow the athlete to achieve their previous levels of
training earlier than normal.
– variety
Figure 1.20
Specificity training
Figure 1.21
AFL players
undertaking
cross-training
exercise
Coaches have a very important role to continually improve an athlete’s
performance and to sustain enjoyment in what they do with the athletes.
The principle of variety is important to maintain motivation and reduce the
athlete’s boredom in training—doing the same drills each week does little to
promote variety.
Coaches need to investigate different ways to meet the training objective
of their athlete while reducing boredom. For example, when team training
partner activities can promote working together, or doing a biathlon will
maintain aerobic fitness rather than doing one continuous run.
– training thresholds
There is a minimum amount of exercise which is required to produce
improvements in athletic performance. For exercise to be effective, it must be
performed:
• with sufficient frequency
• at a high enough intensity
• for sufficient length of duration (usually 20 minutes minimum).
Training thresholds are two points which indicate the zone for athletic
improvement to occur. The thresholds relate to the maximum heart rate of
the athlete. This is calculated using the Karvonen formula (after Dr Martti
Karvonen): 220 minus the athlete’s age. So a 25-year-old athlete has a max
heart rate of 195.
The lowest threshold an athlete must operate at is called the aerobic training
threshold and refers to the lowest point at which training is of benefit to the
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Figure 1.22
200
Aerobic and
anaerobic training
180
thresholds
um
Maxim
te
heartra
Heart rate
160
Anaerob
140
ic thres
hold
120
Aerobic trai
100
ning zone
80
60
70
60
50
40
30
20
Age
athlete. It is roughly 60% of a person’s maximum heart rate. The target heart rate zone (training zone)
is between 60–80% of the maximum heart rate. Working within this zone gives a person the maximum
health and fat-burning benefits from their cardiovascular activity.
When an athlete trains above the aerobic threshold and below the anaerobic threshold they are
working in the aerobic training zone. Training in this zone develops an athlete’s aerobic endurance. All
easy recovery running should be completed at a maximum of 70% maximum heart rate. For example, a
25-year-old person’s aerobic training zone is between the heart rates 117–154. Training between 70–80%
of maximum heart rate will increase the cardiovascular system.
The anaerobic threshold is where OBLA happens. As a result fatigue starts to occur so the body slows
down and trains once more in the aerobic training zone. Another test coaches use is the talk test. If the
athlete struggles to talk in a controlled manner, they are no longer working within the aerobic system but
rather the anaerobic system.
For athletes who rely heavily on the lactic acid system they would train as close as possible to the
anaerobic threshold. Through correct training, it is possible for an athlete to delay the threshold by
being able to increase the ability to deal with the lactic acid for a longer period of time or by pushing the
threshold higher.
– warm up and cool down
Each training session is organised around three areas: the warm up, skills and conditioning, and then cool
down. The warm-up can be divided into three sections: a general body warm-up, stretching and activityspecific where certain muscle groups are used. Overall warm-up should take no more than 10% of exercise
time.
In the first phase, a general warming-up occurs by using major muscle groups. This is designed to raise
the temperature of the body and its structures, such as the muscles. The idea is to increase mobility in
readiness for physical activity while reducing the risk of injury. The warm-up is best accomplished with a
full-body activity, such as jogging, and should last for at about 5 minutes, at an intensity to increase body
temperature yet should not lead to fatigue. Often included after this phase are some stretching exercises
that go through a functional range of motion, holding positions usually between 10–30 seconds.
The cool down is effectively a warm-up in reverse. Cooling down after an aerobic exercise is important
to bring the heart rate back to normal slowly, so that the strain is taken off the heart and prevent blood
pooling in the extremities of the body, such as the feet. If a cool down is not done, muscle stiffness may
occur from waste that was built up in the muscles and not allowed to be worked out with a cool down.
104
factors affecting performance chapter 1
physiological adaptations in response to training
examine the relationship between the principles of training, physiological
adaptations and improved performance
There are various adaptations that an athlete’s body makes as a result of training. These physiological
adaptations will vary in time from one athlete to another, as well as how quickly they are noticed by the
athlete. The physiological adaptations most noticeable are resting heart rate, stroke volume, cardiac
output, haemoglobin level, muscle hypertrophy and the effect training has on fast and slow twitch muscle
fibre recruitment.
– resting heart rate
The heart consists of cardiac muscle and like any muscle that undergoes training it will undergo
hypertrophy and become more efficient. A consequence of training is a lower resting heart rate than pre
training. This is due to a more efficient cardiovascular system as well as stroke volume.
– stroke volume and cardiac output
The stroke volume is the amount of blood pumped out of the heart
per beat. As the heart becomes more efficient the left ventricle actually
becomes bigger and as a result will pump more blood out per beat than
pre training. The heart is also more forceful now with each beat as an
adaptation.
Cardiac output is the amount of blood pumped out of the heart per
minute by the heart. To calculate this, multiply the stroke volume by
the heart rate. The heart rate will rise normally under maximal or submaximal activity to increase the ventilation rates around the body. As
the stroke volume is bigger, the cardiac output will rise accordingly due
to training. This then increases the amount of blood being sent around
the body:
Cardiac output (CO) = Stroke volume (SV)  heart rate (HR)
Activity 12
Sample
student
answer
Figure 1.23
Measuring heart rate
– oxygen uptake and lung capacity
The oxygen uptake refers to the amount of oxygen the body uses
per minute and is the maximum capacity of an individual’s body to
transport and utilise oxygen. It is also known as VO2 max. It is the
strongest indicator of an athlete’s ability in endurance events.
When a trained athlete is performing at maximal levels of work, the
amount of oxygen used by their muscles is higher than pre training.
Through training, an athlete’s cardiac output is increased and ventilation
rates rise as a result of exercise. This allows the athlete to absorb and utilise
oxygen more efficiently during exercise. The greater the number of red, slow-twitch muscle fibres people
have, the more oxygen they will be able to absorb; and they will have higher haemoglobin levels than athletes
with white, fast-twitch fibres. White, fast-twitch fibres tend to reduce the amount of oxygen absorbed.
The oxygen uptake will improve as a result of training. The lung capacity of athletes after undergoing
training will remain the same as they were before training.
– haemoglobin level
The haemoglobin molecule is the substance that the oxygen molecule binds to for transportation around
the body to working muscles and other body parts that requires it for survival. It is found in the red blood
cells. As the oxygen uptake increases with training, so does the haemoglobin content due to increased
efficiency of the cardiorespiratory system.
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Sede n t a r y m a le s u b j e c t
V a r i a b le s
Pre training
Post training
W o r ld - c l a s s
endurance runner
Cardiovascular
HRrest (beats/min)
75
65
45
HRmax (beats/min)
85
183
174
SVrest (ml/beat)
60
70
100
SVmax (ml/beat)
120
140
200
–
Q at rest (L/min)
4.5
+
Q max (L/min)
4.5
22.2
Heart volume (ml)
Blood volume (L)
25.6
750
820
4.7
5.1
4.5
34.8
1200
6.0
Systolic BP at rest (mmHg)
135
130
120
Systolic BPmax (mmHg)
200
210
220
Diastolic BP at rest (mmHg)
78
76
65
Diastolic BPmax (mmHg)
82
80
65
Respiratory
–
YE at rest (L/min)
+
VEmax (L/min)
7
6
6
110
135
195
TV at rest (L)
0.5
0.5
0.5
TVmax (L)
2.75
3.0
3.9
VC (L)
5.8
6.0
6.2
RV (L)
1.4
1.2
1.2
(a-v– )O2 diff at rest (ml/100m)
6
6
6
(a-v )O2 diff at rest (ml/100m)
14.5
15.0
16
Metabolic
–
–
VO2 at rest (ml • kg–1 • min–1)
3.5
3.5
3.5
40.7
49.9
81.9
Blood lactate at rest (mmol/L)
1.0
1.0
1.0
Blood lactate max (mmol/L)
7.5
8.5
9.0
+
VO2max at rest (ml • kg–1 • min–1)
Body composition
Weight (kg)
79
77
Fat weight )kg)
12.6
9.6
5.1
Fat-free weight (kg)
66.4
67.4
62.9
Fat (%)
16
12.5
7.5
HR = heart rate
TV = tidal volume
SV = stroke volume
VC = vital capacity
Q = cardiac output
RV = residual volume
BP = blood pressure
(a-v– )O2 diff = arterial-mixed venous oxygen difference
V = ventilation
VO2 = oxygen consumption
source: Wilmore, J.H., Costill, D.L., Kenney, W.L., Physiology of sport and exercise, p. 239
ta b le 1 . 5
Physiological
changes as a result
of training
106
68
factors affecting performance chapter 1
As haemoglobin will increase with aerobic training, those athletes with fast twitch fibres and who train
anaerobically may not notice a significant increase in haemoglobin content due to their training programs.
– muscle hypertrophy
Muscle hypertrophy refers to an increase in muscle size. As an immediate response to training, the muscle
fibres increase in size as more fluid goes to the muscle. As a response to extended training, the muscles
used will increase in size again as the fibres adapt to the training load and lead to an overall increase in
muscle size. These fibre changes also occur because of structural changes in the fibre by the increased size
of connective tissue or filaments or a combination of both.
– effect on fast/slow twitch muscle fibres
The effect of training on the type of muscle fibres—either fast-twitch (explosive movement) or slow-twitch
(longer slower contraction)—relates almost directly to specificity. Low-to-moderate activity will recruit slowtwitch fibres and increase the cross sectional area of these fibres. As the fast-twitch fibres have not been recruited,
there is little change in their structure. Continued training for endurance can lead to slight structural changes in
fast-twitch fibres, but little evidence has been found to indicate fast-twitch fibres change to slow-twitch fibres.
An increase in the number of capillaries to slow twitch muscle fibres will also result in hypertrophy
of those fibres. These slow-twitch muscles are characterised by a high aerobic endurance capacity that
enhances aerobic ATP energy production system. Our modern lifestyle reinforces the recruitment of
slow-twitch muscle fibres in what we do daily. Any training athletes do for fast-twitch fibres must be
maintained, otherwise the effects of training will be lost due to reversibility.
Activities
Activity 1 (Page 86)
a. Design a presentation for coaches which outlines the following requirements of each
energy system:
• source of fuel
• cause of fatigue
• efficiency of ATP production
• by-products of energy production
• duration that the system can operate
• process and rate of recovery.
b. Complete the table below.
Al a c t a c i d s y s t e m
Lactic acid
o r AT P / C P
system
Ae r o b i c s y s t e m
how it works
fuel
efficiency of ATP
production
duration
cause of fatigue
by-products
recovery
exercise type most
suited for this energy
system
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PDHPE in focus hsc course
Activities cont.
c. What is the dominant energy system for each of the following sports:
• rugby union?
• triathlon?
• surfing?
• netball?
• golf?
Activity 2 (Page 86)
Explain how fatigue occurs when using each of the three energy systems. Give examples of
how this affects sport.
Activity 3 (Page 95)
Write a newspaper report outlining the various types of resistance training.
Activity 4 (Page 95)
Describe two types of flexibility training to an athlete just beginning training in a sport of
your choice.
Activity 5 (Page 95)
Design a strength-training program for a shot putter and a 400-m runner. Consider the use
of reps, sets, and other elements in resistance training.
Activity 6 (Page 95)
Design a circuit for a soccer player using resistance and a circuit with no resistance training.
Activity 7 (Page 95)
Describe the different types of aerobic training?
Activity 8 (Page 102)
Design a suitable warm-up for a sport of your choice.
Activity 9 (Page 102)
Explain how progressive overload can be used on a form of aerobic training and how
performance will subsequently be improved.
Activity 10 (Page 102)
Describe how PNF is different to ballistic stretching.
Activity 11 (Page 102)
Access the Brianmac website and compare the training programs of two elite athletes.
www.brianmac.co.uk
ÂÂ
Activity 12 (Page 105)
Create a poster or PowerPoint presentation summarising the effects of training on; resting
heart rate; stroke volume; cardiac output; oxygen uptake; lung capacity; haemoglobin level;
hypertrophy and muscle fibres.
108
factors affecting performance chapter 1
Review
Questions
1.Analyse the anaerobic and aerobic energy systems and
which system would be more useful for a sport of your
choice.
2.Outline the contribution of the three energy systems
for a sport of your choice.
3.Summarise the ways ATP is resynthesised for each
energy system.
4.Explain how an athlete will use all three energy systems
for energy supply when competing in the marathon
running event.
5.Assess the relevance of the chosen training method for
the sport listed below.
Sp o r t
S u g g e s t ed t r a i n i n g m e t h o d
marathon running
tennis
soccer
continuous training
resistance training
interval training and
flexibility training
6.Assess which types of training are best suited for a
hockey player and for a swimmer in an 800-m race.
How will each of their performances be affected by this
training method.
7.Explain why elite athletes cool down for extended
periods of time after competing.
8.Predict what physiological changes would occur to an
athlete who trains for an extended period close to or at
the anaerobic threshold.
9.Compare the physiological changes of the marathon
athlete in question 4 with an untrained person.
10.Analyse how the principles of training can be applied
to interval or Fartlek training.
11.Analyse how the principles of training could be applied
to circuit training.
12.Examine the relationship between the principles of
training, physiological adaptations and improved
performance.
13.Clarify the role training thresholds play in improving
performance.
Chapter
summary
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