Download chapter 5 – specialised training

SECTION A –
CHAPTER 5
ANSWERS TO QUESTIONS
CHAPTER 5 – SPECIALISED TRAINING
Text between pages 39 and 46, answers to questions on pages 46 and 47 of the text book.
1) a) Plyometric training is a type of power training, which involves performing exercises with maximum power and speed. Describe the main concepts of plyometric training, illustrating your answer with an example of an exercise. Identify the type of sports performer who would most benefit from this training method.6 marks
Answer
3 marks for:
• Plyometric training involves eccentric-to-concentric actions.
• Performed at 100% effort.
• Designed to improve elastic strength.
• Using the stretch reflex to facilitate recruitment of motor units.
2 marks for example of a plyometric exercise:
• Plyometric bounding to develop knee extensor strength:
• A person goes from standing upright position to a deep squat position (eccentric contraction).
• Then performs a two-footed jump, performed quickly to activate the stretch reflex (concentric contraction).
• In time with the concentric phase of the jump.
• The person lands in a squat position and repeats the cycle for a predetermined number of repetitions.
1 mark for type of sports performer who would most benefit from this training method:
• Explosive power athletes such as basketball players, sprinters, jumpers.
b) Discuss the advantages and disadvantages of plyometric training.4 marks
Answer
2 marks for advantages:
• Maximises muscle development by improving power or elastic strength.
• Can be very sport specific. For example, take-off as when jumping and bounding in events such as triple jumping.
2 marks for disadvantages:
• Can cause chronic repetitive trauma injuries such as Achilles tendinosis and shin splints.
• Can cause acute injuries such as sudden ruptures of muscle, tendons and ligaments.
• To vulnerable knee and ankle joints.
c) Why does muscle soreness (DOMS) often occur following a plyometric training session and how could muscle soreness be reduced?4 marks
Answer
2 marks for two of:
• Eccentric action is the primary initiator of DOMS.
• And is associated with damage to muscle tissue and its cell membrane (micro tears).
• And inflammatory reactions within the muscles.
2 marks for two of how muscle soreness can be reduced:
• Within the training session, start training at a low intensity.
• And gradually increase workload to the exhaustive high intensity, eccentric action exercise.
• Use of a thorough cool-down.
• Adequate rest intervals between plyometric training sessions.
• Use of ice baths immediately after the training session.
2) Explain the role of Golgi tendon organs during proprioceptive neuromuscular facilitation (PNF).
4 marks
Answer
• Golgi tendon organs (GTOs) lie within tendons near to the muscle or tendon junction.
• These proprioceptors are sensitive to changes in muscle or tendon tension.
• Following a passive stretch detected by muscle spindle apparatus (phase 1 of PNF).
• The athlete contracts the stretched muscle isometrically for 5-6 seconds (phase 2 of PNF), with the partner inhibiting all
movements.
• GTOs become sensitive to increased tension developed within the agonist muscle.
• And send inhibitory signals to the muscle spindles within the agonist muscle.
• Which override the excitatory signals from the muscle spindles.
• Thus delaying the stretch reflex (i.e. the rapid contraction of the stretched muscle).
• Allowing the muscle or tendon tissue to relax.
• And enabling long-term increase in muscle stretch.
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APPLIED PHYSIOLOGY TO OPTIMISE PERFORMANCE
3) a) Describe the conditions at altitude that could limit performance.
Answer
• Altitude causes hypobaric conditions or a reduction in barometric pressure.
• Resulting in decreased partial pressure of oxygen (pO2) throughout the body.
• Reducing the oxygenation of haemoglobin.
• Air temperature decreases as altitude increases.
• Solar radiation is more intense.
• Thus limiting human activity when compared with sea level performance.
3 marks
b) An elite group of endurance athletes spend three weeks training at 2000 metres. What major physiological responses and adaptations would they expect during this period of acclimatisation? 10 marks
Answer
4 marks for four of immediate physiological responses:
• Pulmonary:
• Hyperventilation occurs immediately.
• As body fluids become more alkaline.
• Due to reduced CO2 (H2CO3) with hyperventilation.
• Corrected by the kidneys, which excretes a more alkaline urine solution.
• Cardiovascular:
• Increased submaximal heart rate.
• Increased submaximal cardiac output.
• Stroke volume remains the same or lowers slightly.
• Maximum cardiac output remains the same or lowers slightly.
6 marks for six of longer term physiological adaptations following 3 weeks of altitude training:
• Cardiovascular:
• Stroke volume lowers.
• Maximum cardiac output lowers.
• Decreased plasma volume.
• Increased haematocrit (the percentage of blood volume occupied by red blood cells).
• Increased haemoglobin concentration.
• Increased total number of red blood cells.
• Possible increased capillarisation of skeletal muscle.
• Cellular changes:
• Increased mitochondria.
• Increased oxidative enzymes such as pyruvic dehydrogenase.
• Net effect is to improve the aerobic working capacity of muscles to compensate for the reduced pO2.
• And to improve the capacity of the oxygen transport system.
• To purge the oxygen debt.
c) What is meant by the concept ‘living high and training low’? Identify two advantages of using this acclimatisation method. 6 marks
Answer
4 marks for four of:
• ‘Living high and training low’ is an at-home acclimatisation method achieved at sea level.
• The athlete rests and sleeps in a hypobaric or hypoxic chamber.
• Created by a hypoxic generator that continually feeds altitude-stimulating hypoxic air into the tent.
• The hypoxic chamber provides an environment in which the athlete will gain the beneficial physiological adaptations expected from
being exposed to hypobaric conditions.
• This is called ‘living high’.
• ’Training low’ refers to the athlete maintaining a sea level training environment.
2 marks for two of advantages:
• Less costly.
• Less disruptive to lifestyle, such as family relations.
• Maintains relationships and support systems such as quality training facilities, the personal coach, training group and medical team.
Questions and answers 21
SECTION A –
CHAPTER 5
ANSWERS TO QUESTIONS
4) a) How can a balanced diet be manipulated to increase an athlete’s glucose reserves prior to a marathon race?
6 marks
Answer
• Carboloading (or glycogen loading) before the event (modern method).
• This consists of tapering of training, whilst eating 50% CHO diet.
• Partially depletes glycogen stores.
• Therefore energy levels are not compromised.
• And glycogen synthase activity is increased.
• Then, gradually increase CHO intake to 70% of diet.
• With light training.
• Day of rest and 70% CHO diet.
• Repletes glycogen stores above normal level on day of marathon.
• Referred to as glycogen supercompensation.
• Taking in isotonic fluids during the event will top up blood glucose levels during the event.
b) Carbohydrates are used as an energy source during both aerobic and anaerobic conditions. It is therefore beneficial that an elite athlete’s stores of carbohydrate are at a maximum before competition day. Discuss the advantages and disadvantages of glycogen loading. 4 marks
Answer
2 marks for advantages:
• Enhanced glycogen stores in muscle and liver.
• Overall effect is for overall times in aerobic activities beyond 90 minutes to improve significantly.
2 marks for disadvantages:
• Increased body mass due to increased water retention.
• Needed for enhanced glycogen storage.
• During CHO depletion phase decreased energy levels.
• And increased fatigue (if using classic 10 day method of carboloading).
% of maximum training intensity
5) Periodisation is a training concept that explains the variation in training volume and intensity over a specific period of time.
Outline the basic structure of a single periodised year and illustrate how a coach is able to use this structure when planning a
training programme for an athletics group.
14 marks
Answer
• Diagram or chart showing the layout of a single periodised year (see figure AQ5.1). figure AQ5.1 – a single periodised year
2 marks for features of periodised year:
• Year blocked into periods lasting
months
nov dec
jan feb
mar
apr may jun
jul
aug sep oct
2 to 6 months each.
phases
1
2
3
4
5
6
• Labelled preparation, competition,
periods
preparation
competition
recovery, transition.
5 marks for use of the structure:
recovery/transition
• During preparation phase, the athlete will do
gross conditioning training.
• Involving fitness, strength, speed or cardiovascular endurance
work depending on the events or sport being performed.
figure AQ5.2 – training intensity by mesocycle
• This phase will be split up into mesocycles lasting
between 4 and 6 weeks.
training load variation
• Each mesocycle will have its own aims.
120
• For example to improve strength, speed, fitness,
and so on.
100
• Each cycle will have progression and overload.
• Each cycle will follow a plan for each fitness
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component like that in figure AQ5.2.
C
B
D
A
• Each mesocycle will be split up into microcycles
lasting typically one week.
mesocycles of 4 weeks
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time
APPLIED PHYSIOLOGY TO OPTIMISE PERFORMANCE
% loading
• The training intensity will vary according to a plan as in figure AQ5.3.
figure AQ5.3 – variation in training
• This is to allow recovery after intense training.
intensity during a microcycle
• And to spread out all the different elements of training so that learning
can take place when the athlete is recovered.
100
• Microcycles will include rest and recovery.
80
• Mesocycles can include rest and recovery - this will be built into the
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training plan so that injury may be avoided.
5 marks for the competition period includes:
40
• Reduction in training loads.
20
• Tapering in preparation for important competitions, for example
0
the Olympics.
time
day day day day day day day
• Maintenance of sufficient intensity to keep and possibly develop the fitness
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1
2
3
4
5
7
achieved in the preparation period.
• This period will again be organised into mesocycles and microcycles.
2 marks for the recovery period includes:
• Almost complete reduction in training intensity.
• To allow rest and recovery.
• Best achieved actively – playing games or undertaking another activity to keep basic fitness during this period.
• Without risk of injury or overtraining.
6) Discuss the role of the thermoregulatory centre in maintaining the core temperature of the body.
Answer
• The thermoregulatory centre is situated in the hypothalamus.
• It consists of a hot and a cold centre.
• Its job is to maintain the body’s core temperature at around 37oC.
• Body temperature varies with temperature fluctuations in the environment.
• And as a result of the effects of physical activity.
• Sensory feedback alerts the hot or cold centres to respond to temperature changes.
• By balancing heat production in the body with heat loss to the environment (thermoregulation).
3 marks
7) a) What are the major avenues for loss of body heat energy?
Which of these four pathways is important for controlling body temperature at rest, and during exercise? 6 marks
Answer
4 marks for the major avenues:
• Radiation.
• Conduction.
• Convection.
• Evaporation.
1 mark for which of these four pathways is most important:
• Radiation is the primary method for discharging the resting body’s excess heat.
1 mark for during exercise:
• Evaporation is the primary method for heat dissipation during exercise.
b) What happens to the body temperature during exercise and why?
Answer
• Increased skeletal muscle activity increases the core temperature.
• By increasing metabolic heat production.
• Increased sweat gland production decreases the core temperature.
• By increasing evaporative sweat loss.
4 marks
8) How does the body regulate temperature when an elite athlete is training in warm climate?
Answer
• Autonomic nerves from the hot centre of the hypothalamus cause:
• Vasodilation of smooth muscle in the skin arterioles.
• Directing blood to the skin for heat transfer out of the body.
• Decreased muscle tone.
• And increased sweating.
3 marks
Questions and answers 23
SECTION A –
CHAPTER 5
ANSWERS TO QUESTIONS
9) What are the physiological effects of dehydration on an athlete and how does this affect exercise performance? Answer
• Fluid loss decreases plasma volume.
• This decreases blood pressure.
• Which in turn reduces blood flow to muscles and skin.
• In an effort to overcome this, heart rate increases and stroke volume decreases.
• To maintain a nearly constant cardiac output (known as the cardiovascular drift).
• Because less blood reaches the skin, heat dissipation is hindered.
• And the body retains more heat.
• And so body temperature increases.
• These physiological changes will decrease exercise performance.
• Dehydration promotes renal retention of water and sodium.
• Which makes the athlete thirsty.
• If the athlete does not rehydrate there will be continued circulatory distress.
4 marks
10) List four environmental factors that limit the ability of an athlete to continue to exercise in hot conditions.
Answer
• Air temperature.
• Humidity.
• Air velocity.
• Amount of thermal radiation.
4 marks
11) Describe how an athlete is able to control his or her body temperature during a marathon race.
Answer
• Replace body fluids to prevent dehydration and over heating.
• Wear suitable clothing such as mesh running vest.
• That allows air to circulate.
• Hence body is cooled by evaporation of sweat, convection and radiation.
• Use sponge stations to cool down body parts.
4 marks
12) Why is humidity an important factor when an athlete is performing in high temperatures? Why are wind and cloud cover
important?
4 marks
Answer
2 marks for humidity:
• Water vapour in the air plays a major role in evaporative heat loss.
• Hence high humidity limits sweat evaporation and heat loss.
2 marks for wind and cloud cover:
• Wind increases heat loss by convection.
• Known as the windchill factor.
• Cloud cover reduces heat gain by solar radiation.
13) Winter sports performers regularly compete in extreme cold conditions often held at altitude.
a) How does the human body physiologically respond to cold, hypobaric conditions? 6 marks
Answer
3 marks for cold conditions:
• Peripheral vasoconstriction decreases the transfer of core heat to the skin.
• Thus decreasing heat loss to the environment.
• Shivering increases metabolic heat production to help maintain or increase body temperature.
• Performer gets acclimatised to cold conditions (known as habituation).
• Long-term exposure to cold results in increases in subcutaneous fat.
• Leading to greater cold tolerance.
3 marks for hypobaric conditions:
• Hypobaric means low atmospheric pressure, as experienced at altitude.
• Hence reduced oxygen pressure (pO2).
• And hypoxia – reduced pO2 throughout the body.
• Upon initial ascent to altitude the body increases both heart rate and breathing rate to compensate for decreased oxygen content.
• Sports performer may suffer from headaches and dizziness.
• Performer gets acclimatised to hypobaric conditions by creating more haemoglobin, myoglobin, mitochondria and oxidative enzymes to
compensate for effects of hypoxia.
• Hence initial response to hypoxia is overcome.
.
• And acclimatisation process leads to improved aerobic performance due to increase in VO2max..
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APPLIED PHYSIOLOGY TO OPTIMISE PERFORMANCE
b) How can an athlete minimise excessive heat loss during cold exposure? 2 marks
Answer
• By not exposing skin to the cold.
• By wearing appropriate kit such as thermal gloves and hat.
• And Gore-tex training jacket that enables moisture to escape, whilst keeping out moisture from the environment.
• By wearing thin layers of sports clothing to trap warm air between layers.
• By wearing compression clothing next to skin that is tight fitting and insulating.
c) What factors should be considered to provide maximum protection for sports performers exercising in a cold environment? 3 marks
Answer
• Recognise the signs and symptoms of hypothermia.
• Size of performer: small people will lose temperature much more quickly than large people.
• Because of their increased surface area to body mass ratio.
• Protective insulating light clothing.
• For example, bobsleigh performers wear all-in-one body compression suits.
• Ensure safe environmental conditions.
• For example, awareness of windchill factor (wind increases heat loss by convection) or risk of avalanches.
14) Many elite swimmers use blood lactate sampling during training as a means of establishing their training load.
a) What do you understand by the term lactate threshold? 2 marks
Answer
• The point at which blood lactate begins to accumulate substantially.
• Above resting concentrations during exercise of increasing intensity.
• Also known as the onset of blood lactate accumulation (OBLA).
• Lactate threshold represents a significant shift towards anaerobic glycolysis, which is responsible for the formation of lactate or
lactic acid.
.
b) How is lactate threshold related to VO2max.? 2 marks
Answer
.
• Lactate threshold is usually expressed as a percentage
of VO2max. at which it occurs.
.
• So ability to perform at a higher percentage of VO2max. reflects a higher lactate threshold.
c) How might knowledge of blood lactate levels taken during a swimming session assist both coach and elite swimmer?
2 marks
Answer
• Lactate sampling will tell the coach to increase or decrease training
intensity as required.
.
• This means that OBLA can be pushed to a higher percentage VO2max. .
• Speed of reduction in lactate levels will indicate how much recovery is needed between repetitions and sets.
15) a) Show how the data in the following equation can be used to calculate the respiratory exchange ratio (RER) and identify which fuel food is being used. Show your workings. 6O2 + C6H12O6 è 6CO2 + 6H2O + energy 3 marks
Answer
• RER = 6CO2 = 1.00
6O2
• Therefore fuel food is glucose.
b) How can this information be of value to an elite sports performer? 2 marks
Answer
• Estimation of RER can inform sports performer whether or not he or she is working anaerobically or not.
• And so give a good indication of training intensity.
• And energy expenditure.
Questions and answers
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