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Transcript of ©Anthony Dowson - Amazon Web Servicesverulam.s3.amazonaws.com/resources/ks5/pe/A2 PE Verulam...
Walking your talk is a great way
to motivate yourself. No one
likes to live a lie. Be honest with
yourself, and you will find the
motivation to do what you advise
others to do. Vince Poscente
©Anthony Dowson
Verulam School
Workshop/Revision Session – Feb. 2012
Name___________________
"It is one of the strange ironies of this
strange life that those who work the
hardest, who subject themselves to the
strictest discipline, who give up certain
pleasurable things in order to achieve a
goal, are the happiest men (or women)”.
Brutus Hamilton
OCR Syllabus overview
Component of syllabus A*/A B C D E U
Concepts define energy (to include chemical, kinetic and potential), work and power and identify the units they are expressed in.
ATP
explain the role of ATP; the breakdown and resynthesis of ATP; the principle of coupled reactions and exothermic and endothermic reactions.
ATP
res
ynth
esis
explain the contribution made by each energy system in relation to the duration and intensity of exercise.
explain how an individual’s mix of muscle fibre type might influence their reasons for choosing to take part in a particular type of physical activity.
explain the three energy systems: adenosine triphosphate phosphocreatine (ATP/PC) (alactic); the lactic acid system; the aerobic system; (to include the type of reaction (aerobic or anaerobic), the chemical or food fuel used, the specific site of the reaction, the controlling enzyme, energy yield, specific stages within a system, and the by-products produced);
Ener
gy C
on
tin
uu
m identify the predominant energy system used related to the type of exercise
(duration and intensity);
explain the inter-changing between thresholds during an activity (eg the onset of blood lactate accumulation (OBLA)); the effect of level of fitness, availability of oxygen and food fuels, and enzyme control on energy system used.
The
reco
very
pro
cess
explain how the body returns to its pre-exercise state: the oxygen debt/excess post exercise oxygen consumption (EPOC); the alactacid and lactacid debt components (to include the processes that occur and the duration of each component); replenishment of myoglobin stores and fuel stores and the removal of carbon dioxide;
explain the implications of the recovery process for planning physical activity sessions (eg training intensities, work/relief ratios).
Aer
ob
ic C
apac
ity
define aerobic capacity and explain how a performer’s VO2 max is affected by individual physiological make-up, training, age and sex
describe and apply methods of evaluating aerobic capacity (eg multi-stage fitness test, PWC170 test);
candidates should assess their own VO2 max, comparing their result with the aerobic demands of their chosen activities
describe different types of training used to develop aerobic capacity (continuous running; repetition running; fartlek and interval training);
explain the use of target heart rates as an intensity guide
describe the energy system and the food/chemical fuels used during aerobic work
explain the physiological adaptations that take place after prolonged periods of aerobic physical activity (eg an increase in stroke volume);
plan a programme of aerobic training based on their own assessment of their aerobic capacity and the requirements of their activity
Per
iod
isat
ion
Candidates should build on their knowledge of training principles (overload, progression, specificity, reversibility, moderation and variance) acquired in GCSE Physical Education by applying their knowledge to periodisation
Candidates should be able to: define periodisation; macro, meso and micro cycles
plan a personal health and fitness programme that will promote sustained involvement in a balanced, active and healthy lifestyle; the plan should include the principles of training.
Use of Physical Activity Readiness Questionnaire (PARQ).
Component of syllabus A*/A B C D E U
Stre
ngt
h
define types of strength (to include strength endurance, maximum strength, explosive/elastic strength, static and dynamic strength);
• demonstrate knowledge and understanding of factors that affect strength (fibre type and cross sectional area of the muscle);
• describe and apply methods of evaluating each type of strength (eg grip strength dynamometer);
describe and evaluate different types of training used to develop strength (the repetition, sets and resistance guidelines used to improve each type of strength);
use of multigym, weights, plyometrics and circuit/interval training (with reference to work intensity; work duration; relief interval; number of work/relief intervals);
describe the energy system and the food/chemical fuels used during each type of strength training;
explain the physiological adaptations that take place after prolonged periods of physical activity (to include neural and physiological changes to skeletal muscle);
plan a programme of strength training based on their own assessment of their strength and the strength requirements of their activity
Flex
ibili
ty
define flexibility (to include static and dynamic flexibility
demonstrate knowledge and understanding of factors that affect flexibility (type of joint; length of surrounding connective tissue)
describe and apply methods of evaluating flexibility (eg sit and reach test; goniometer (angle measure));
describe different types of training used to develop flexibility (including static (active and passive), dynamic, ballistic and proproceptive neuromuscular facilitation (PNF));
explain the physiological adaptations that take place after prolonged periods of physical activity (to include physiological changes to skeletal muscle and connective tissue)
plan a programme of flexibility training based on their own assessment of their flexibility and the flexibility requirements of their activity
Bo
dy
Co
mp
osi
tio
n
explain what is meant by body composition
describe different methods of assessing body composition;
calculate the body mass index (BMI) of an individual;
demonstrate knowledge and understanding of basal metabolic rate (BMR) and the different energy requirements of different physical activities (use of metabolic equivalent/MET values);
estimate their daily calorific requirements (dietary/nutritional intake) based on their BMR and average additional energy consumption;
evaluate critically their own diet and calorie consumption;
demonstrate knowledge and understanding of the health implications of being overweight or obese and how this affects involvement in physical activity.
Ergo
gen
ic a
ids
• explain the positive and negative effects of each type of aid together with the type of performer who would benefit from its use;
• identify the legal status of each type of aid;
• evaluate critically the use of ergogenic aids in order to be able to make informed decisions about their use.
use of dietary manipulation, pre-/post-competition meals/supplements and food/fluid intake during exercise
use of creatine supplements and human growth hormone
gene doping
blood doping and recombinant erythropoietin (Rh EPO)
use of cooling aids to reduce core temperature and aid recovery
use of training aids to increase resistance, eg pulleys; parachutes
other aids can be considered and candidates should already have prior knowledge of the effects of alcohol, caffeine and anabolic steroids
Body Composition
It is unlikely that during your workshop you will have time to take all of the measures listed below. Please ensure you ask your tutor which measurements are needed. Use the guidance sheets and ensure you are as accurate as possible with your results.
From the measurements below it is possible to compute a person’s;
Body mass index Body fat percentage Amount of muscle tissue Somatotype
Height_______________cm Weight______________kg BMI_________________ BMI = weight in kg / height in m2
Body Composition (BIA method)
Body fat_____________% (skinfold method)
Body fat_____________% Bone Breadths Femur_____________cm Humerus___________cm Girths Flexed arm__________cm Calf________________cm
Skinfolds Biceps______________cm Triceps_____________cm Chest (men)_________cm Subscapula__________cm Iliac crest___________cm Suprailiac___________cm Abdominal__________cm Thigh_______________cm Medial calf__________cm
Lactate threshold and OBLA
Although VO2 max testing is carried out to assess an athlete’s endurance, frequently sports scientists will carry out testing to evaluate an athlete’s lactate response to running at a variety of intensities. To carry out lactate testing on a cycle ergometer the athlete is required to work for 4 minutes at increasing intensities. Starting at a low intensity at the end of each 4 minutes a capillary blood sample is taken. The athlete will continue for 5-8 stages/increments until they work at approximately 70% of VO2 max. A typical lactate response for a well-trained endurance athlete running at 7 different speeds is shown below. A number of different terms are used to describe the changes that occur to blood lactate when this type of testing is carried out.
Lactate threshold is accepted as the first ‘break-point’ in blood lactate accumulation (about 15 km/h on the diagram below).
Onset of blood lactate accumulation (OBLA) is identified as the work-rate that corresponds to a blood lactate of 4 mmol.L-1. It is now known that if a person exercises at a speed below OBLA for approximately 30 minutes blood lactate levels will reach steady-state (or even drop slightly) as the test progresses. However, if they worked at an intensity above OBLA for this length of time lactate values will rise continuously until exhaustion occurred. The greater the work-rate above OBLA, the faster the person will become fatigued and have to stop exercising.
Lactate testing is crucial for endurance athletes as it enables them to identify correct pacing for racing, enables them to monitor training effectiveness and can be used to training programmes at the correct intensity.
Lactate Threshold & OBLA testing
Methods
A typical blood lactate and heart rate response to an incremental
exercise test
0
2
4
6
8
10
12
13 14 15 16 17 18 19 20
Running Speed (km/h)
Blo
od
la
cta
te (
mM
)
100
110
120
130
140
150
160
170
180
190
200
He
art
ra
te (
bp
m)
Blood Lactate (mM) Heart rate (bpm)
Results Min
& Workload
HR RPE Blood Lactate
(mmol.L-1)
Resting
1
2
3
4
5
6
7
8
10
11
12
13
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15
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19
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24
28
Discussion (include information on; what the results mean, what the results mean for
performance, reliability and validity of testing, knowledge of energy systems, how
training will affect results etc.)
Questions 1. On the graph below draw a new line to represent the changes you would expect to occur after a person
undertook 8 weeks of continuous and interval training to improve their endurance. (2)
2. Why is lactic acid produced in the muscle? (3 marks)
3. What affect does lactic acid have within the muscle? (4)
4. What happens to lactic acid when it has been produced in the muscle? (3) 5. Why do some athletes in events that take 2-10 minutes to complete take sodium bicarbonate as a
performance enhancing substance? (3)
A blood lactate response to an incremental exercise test
0
1
2
3
4
5
6
7
8
9
13 14 15 16 17 18 19
Running Speed (km/h)
Blo
od
la
cta
te (
mM
)
Energy Systems Summary
When a person starts to exercise the muscles work to move the bones.
Chemical or potential energy is converted into the ____________ energy that
enables muscular contractions.
The only fuel that can actually be used to power muscular contractions is
__________________(________). ________ is found in the ___________
of the muscle and its breakdown is catalyzed (speeded up) by the enzyme
__________. ATP is broken down to __________ and ______, releasing
energy and causing the ‘ratchet mechanism’ of the sliding filament theory.
There is a limited amount of ATP so when it is broken down it needs to be
________________. Other fuels found in the body are used to do this, so
despite providing us with energy they do not directly power our muscular
contractions. The other fuels are PCr, carbohydrates (glucose/glycogen), fats
and proteins. Proteins only make a small contribution to ATP resynthesis (less
than 10%) so we do not need to worry about them in A Level PE. These three
fuels are used in 3 different energy systems; The alactic system, the lactic
acid system and the aerobic system.
The table below shows which fuels are used by each of the energy systems.
Alactic system Lactic acid system Aerobic system
_______________ _______________ _______________
_______________
YOU MUST REMEMBER THAT DURING ANY EXERCISE, IT DOESN’T MATTER WHAT
THE INTENSITY AND DURATION IS ALL THREE ENERGY SYSTEMS WILL BE
OPERATING. HOWEVER, THEIR CONTRIBUTION TO ENERGY PRODUCTION (OR ATP
RESYNTHESIS) VARIES. THIS DEPENDS ON; THE AMOUNT OF FUELS THAT ARE
AVAILABLE, THE INTENSITY/DURATION AND ANY PREVIOUS EXERCISE.
_______________________ System
AKA the _______ or _____________ system
During maximal and high intensity work of short duration the _______ SYSTEM
predominates. The breakdown of ATP can be summarised below.
ATP ______ + _____ + Energy
During explosive actions ATP is used very quickly so must be resynthesised very
quickly too. The ________ system is the best system to use in these instances
because the breakdown of PCr is very quick. The breakdown of PCr can be
represented by this equation.
______ ______ + _____ + Energy
This energy is then used to resynthesise ATP by joining ADP and P back together.
The enzyme that catalyzes the breakdown of PCr is called ________ ________ and
this reaction also occurs in the ______________.
Some textbooks will write the equation slightly differently and you may see the
equation written in this way.
ADP + PCr ATP + Cr
Like ATP, there is only limited amounts of ______ in the muscle. When we sprint at
maximal speed the levels of ______ drop very quickly as they are being broken down.
This energy system will predominate during ____________ intensity exercise that
lasts for under _______ seconds.
Examples of activities that could be given include;
Elite sprinter in 100 m race (remember the elite bit as not many of us can run a 100 m race in under 10 seconds)
Give another athletics example
Give a games example
After exercise where the PCr levels have dropped to almost zero (e.g. after a
200 m sprint), it takes approximately 3 mintues to fully resynthesise PCr.
_______________________ System
or ANAEROBIC GLYCOLYSIS
The only fuel that is used during anaerobic glycolysis is ________________. The
body stores limited amount of _________________ in the body; only 300-500
grams in the muscles, approximately 100 grams in the liver and 5-10 grams in the
blood. Carbohydrate stored in the muscle and liver is usually in the form of
______________ (long chains of glucose). Glucose is found in the blood… it is
released by the liver when blood glucose levels fall. A fall is caused by exercising or
through starvation. Each molecule of glucose stores lots of energy. Most of the
energy that we can use comes from the hydrogen and electrons that help to make up
the monosaccharide. To fully appreciate the lactic acid system we must have an
overview of the breakdown of glucose. Glucose is made up of 6 _________ atoms, 12
_________ atoms and 6 _________atoms. We must safely break up glucose so we
can release the energy that is stored in the molecule without being left with harmful
or toxic by-________________. An example is carbon ___________. Glycolysis is
the partial breakdown of glucose. Within the _____________ (the muscle’s
cytoplasm), glucose is broken down in 10 stages, by 10 different enzymes (including
hexokinase, glycogen phosphorylase and phosphofructokinase [______]), into two
molecules of pyruvate. In the process of breaking down glucose (into two pyruvates),
enough energy is released to resynthesise 2 ATP molecules. During glycolysis some
hydrogen atoms are removed. If there is a plentiful supply of ___________ within
the muscle then they are carried (by _________) into the mitochondrion. However,
when the intensity of exercise is high then there will not be enough NAD+ molecules
available to transport the hydrogen to the mitochondria, so hydrogen would build up.
An increase in hydrogen within the sarcoplasm would be very damaging to the muscle
and result in breakdown of muscle tissue. For this reason the enzyme
________________(_______) joins a pyruvate with a hydrogen. The new molecule
is called ______________________. A simple way of representing this energy
system is;
Glucose + 2 ADP + 2 P 2 pyruvates + 2 ATP
The lactic acid system predominates in _____________ intensity exercise that lasts
for between ____ __________________ and _____ __________________.
Examples of activities that could be given include;
Running a 200 m race
Running an 400 m race
Swimming in a 200 metres front crawl race.
A few examples from games situations would be
Give example
Give example
The production of too many hydrogen atoms and lactate by this system will lead to
fatigue. Anyone giving their best effort in a 400 m or 800 m race is likely to have
experienced this in the last 50 m, when it feels like the legs are ‘burning up’ and
incapable of continuing to drive. The affect of hydrogen on lactate is shown in the
table below
There is a ______________in pH / an _____________________ in acidity
The change in acidity within the sarcoplasm leads to reduction in the action of
certain glycolytic enzymes, specifically _____________. This reduces the
bodies ability to use the lactate system to resynthesise pH.
The change in acidity also affects the function of lipases meaning there is a
reduction in ___________, and increased _________________ utilisation.
The hydrogens or lactate is also thought to interrupt ______________-bridge
formation so there is some mechanical fatigue.
During exercise the body tries to deal with any lactate that has been produced. To
maintain appropriate pH levels in the sarcoplasm lactate is ejected through the outer
membrane. If it is produced in the ______________ twitch muscle fibres it may
pass into the ___________ twitch ones. This is because the ____________ twitch
muscle fibres have a better oxygen supply, as oxygen is needed to deal with the
lactate. Alternatively it will be passed into the ________________ where it can be
transported around the body. When it travels around the body it will be taken into
tissues and organs that have a good blood (and therefore ______________) supply,
for example the respiratory muscles or the heart. It can also be taken up by less
active muscles, like the ones in the face… unless the person is grimacing a lot! In
these tissues the lactate is ___________________, which means that it is broken
down as a fuel, using oxygen, into carbon dioxide and _________________.
Pyruvate + O2 energy + H2O + CO2
Lactate is also processed in the liver, where it is can be converted into
___________________, ____________________ or
______________________.
A tiny amount of lactate will be lost in sweat or urine. However, neither of these
processes is suitable as they both result in wasted energy.
The ____________________ System
The __________________ system is the most efficient system. There are three
stages to this system; ______________________, _____________ ____________
and the ________________ __________________ _________________.
The purpose of the aerobic system is to safely remove the energy from ____________
or carbohydrates. Essentially it is the removal of hydrogen from these fuels that is
required and this occurs in the first 2 stages. In the 3rd stage the energy from the
hydrogen atoms is harnessed to resynthesise ATP. The process requires
_________________ so this must be inhaled in the ____________________ and
transported to the muscles.
Stage 1: _________________________
Glycolysis is the same as the lactate system, however, when enough oxygen is present the
end products (____________________ and ____________________) are passed into
the mitochondrion to be further processed and there will be no __________________
production.
Stage 2: _________________________
As mentioned, the function of this stage is to remove hydrogens so these can be taken to
stage 3. In stage 2, ________________ (3 carbon sugar) is initially converted into a
molecule called _________________ (2 carbon sugar) (through the removal of a carbon
dioxide molecule and the adding of a co-enzyme ‘CoA)’. This then joins with
____________________ (4 carbon sugar) to form a 6 carbon sugar, which is called
_________________ ____________. In a number of steps citric acid is broken down
into _____________________ and in the process more hydrogen is removed and taken
away by _____________________ or __________________, and more carbon
dioxide is released. One _________ molecule is resynthesised for each pyruvate, which
means that 2 are re-formed for each original glucose molecule.
Stage 3: _____________________________
The electron transfer chain is he most complex stage to understand as there is lots going
on. Within the inner membrane there are many protein carrier molecules which work to
resynthesise ATP using the energy from the hydrogen atoms. The first thing that
happens is that each hydrogen is split into a proton and an electron. The electron passes
down the carrier molecules in a specific order, in a process called a ‘series of REDOX
reactions’. The energy from the electron is used to transfer hydrogen ions from the
matrix of the mitochondria into the ________________________
_____________________ space. The build up of hydrogen ions (an atom will sometimes
become an ion when it loses an electron) leads to a massive electrochemical charge. The
hydrogen ions pass back out into the matrix of the mitochondria, powering a protein
complex called _________________________, which resynthesises lots of ATP. In the
meantime, the final protein carrier molecule will be taking up and holding some oxygen.
The oxygen molecule is split into two and each one is combined with two
__________________ atoms to form ___________________. For each molecule of
glucose there will be 32 to 34 ATPs produced in the ETC… so the mitochondria really is
the ‘powerhouse’ of the muscle.
A summary of the amount of ATPs resynthesised through the breakdown of glucose is
shown below:
Stage 1: ___________________________ = ______ ATPs
Stage 2: ___________________________ = ______ ATPs
Stage 2: ___________________________ = ______ to _____ ATPs
Total from all stages = ______ to _____ ATPs
Fats can also be used as a fuel They are broken down into acetyl CoA and enters
________________ ___________________ in the same way that carbohydrates do.
However, fats require more O2 to be broken down so are not the preferred fuel when
the intensity of exercise increases.
June 2010
The recovery process returns the body to its pre-active state. Describe the main
processes involved in the alactacid component of recovery. (5 marks)
Explain what is meant by the term metabolic equivalent/MET. How can
knowledge of METs be useful to a performer? (4 marks)
Carbohydrates are a valuable source of energy. Why is it important for a
performer to ensure that they have adequate supplies of carbohydrate? How
can a performer make sure that they don’t deplete their stores of
carbohydrate? (6 marks)
* Devise a six month training programme that will develop aerobic capacity.
Justify your programme by referring to the theory of periodisation and the
principles of training. (20 marks)