pe - aos 2

4.7 - qualitative movement analysis

• qualitative movement anlysis -

• purposes

  • diagnosis of strengths + weaknesses of players or teams

  • to obtain a result or rank in competition

  • for talent identification or team selection

  • to predict future performance results

4 stages

1. preparation

2. observation

3. evaluation

4. error correction

4.7 - preparation

• aim - what to analyse + the purpose of the analysis

• must gather relevant info on

  • sport - rules + terminology

  • individual + team - team dynamics, individual’s, age, gender, history, level, etc

  • performance - what the skill is

  • technique - how to execute skill successfully

4.7 - observation

• aim - consider factors of the performer that may influence their performance + factors that may impact your ability to observe

types

• direct

  • note taking

  • fill in a sheet/form

• digital recording

  • any recording device (visual/audio) ex. bio trackers

• difference is accessibility - digital recording costs more money + time

4.7 - observation - considerations

• viewing position

• viewing plane

• viewing reliability

4.7 - evaluation

• aim -

• questions asked during evaluation

  • what is the problem?

  • what is causing the problem?

  • how am I going to correct this most effectively?

4.7 - evaluation - subjectivity

• this stage is where subjective bias can enter. (during any of above questions)

  • subjective data - subjective data that can be observed + evaluated differently by different observers → subjective bias

  • objective data - data, often numerical, that although is observed the same, can be evaluated differently by different observers → subjective bias

to avoid subjectivity:

• ask for input from multiple people (best intervention)

• ensure significant time is spent on training judges/coaches to accurately evaluate performance

4.7 - evaluation - validity + reliability

• validity - the capacity of a test to measure what it is intended to. is it testing what you’re claiming it tests?

• reliability - the ability of a test to reproduce similar results when condicted in identical/similar conditions, contexts and situations. similar results if test is replicated multiple times.

4.7 - error correction

• aim - strengths + weaknesses have now been estabilished → correct + create an intervention

implementation

• feedback

  • augmented

  • instructive correction

  • providing learner with:

    • knowledge of performance

    • feedback on improving technique

• modified practice

  • during practice

    • breaking skills into easier parts

    • creating easier game situations then adding difficulty

  • closed environment then slowly make more open

4.7 - error correction - intervention

5.1

• acute responses to exercise - immediate physiological responses in the body to support the increased energy demand during exercise. responses only last for the duration of the activity

  • depend on the intensity + type of activity

  • are evident from the start to the end of the activity

  • due to the increased demande for energy by the working muscles

5.2 - oxygen uptake

5.3 - cardiovascular system

• Vo₂ max - the maximum amount of oxygen the body can uptake, transport and utilise per minute. % of Vo2 max gives best measure of exercise intensity

• diffusion - CO₂ waste product is removed and O₂ is added in gaseous exchange between the alveoli (respiratory system) and capillary (cardiovascular system) → capillary leads to pulmonary vein which leads to heart → blood pumped to body where muscles produce energy. (diagram above)

• diffusion - occurs when molecules move from an area of high concentration to an area of low concentration

5.3 - acute responses from the cardiovascular system

1. increased heart rate →

2. increased stroke volume →

3. increased cardiac output →

4. increased blood pressure →

5. redistribution of blood flow →

6. increased a-VO2 Diff

5.3 - increased heart rate

• heart rate

  • number of contractions of the heart muscle in a minute, measured in bpm.

  • at rest, approximately 60-70. during exercise, increases in a linear fashion with exercise intensity (%Vo₂ max), until near-maximal intensity is reached, where it drops a bit. (see graph)

• maximum heart rate - highest rate your heart can safely reach during exercise. MHR = 220 - your age

• purpose

  • in response to increased energy demand from muscles → first response is increase in HR

  • increase in HR → the heart pumps oxygenated blood around the body at a greater rate → greater amount of blood delivered for diffusion and use by working muscles for aerobic energy production + aids in the removal of waste products

  • a rise in HR before exercise = anticipatory rise

5.3 - increased stroke volume

• stroke volume

  • the amount of blood ejected from the left ventricle with each contraction, measured in mL.

  • during exercise, SV increases in a linear fashion, until around 40-60% of maximal intensity (% Vo₂ max) where SV plateus. Vo₂ max differs relative to athlete’s training, therefore point at which SV plateus is relative to athlete’s training.

• purpose - increase in SV → more blood pumped per contraction → more blood available for the body

5.3 - increased cardiac output (Q)

• cardiac output

  • the total amount of blood ejected by the left ventricle per minute, measured in L/min

  • Q = HR x SV

  • at rest, 5-6L/min. at maximal intensity exercise, can increase to 20-25 L/min (~5x more than rest).

  • during submaximal intensity exercise, Q increases in a linear fashion in response to intensity, and is a result of both an increase in HR and SV

  • but as exercise increases towards high intensity, SV plateus, and any increase in Q is due to an increase in HR.

• purpose - increase in Q → greater amount of blood pumped per minute → greater amount of blood delivered/transported for diffusion and use by working muscles for aerobic energy production

5.3 - increased blood pressure

• blood pressure

  • the pressure exerted by the blood against the walls of the arteries during different phases of the heart,

  • blood pressure = systolic/diastolic mmHg (millimitres of mercury).

  • systolic - when the left ventricle contracts

  • diastolic - when the left ventricle relaxes

  • 120/80 mmHg = normal bp at rest. (120 systolic, 80 diastolic).

• purpose

  • systolic bp - increases with all types of exercise. during continuous exercises such as running, can increase to 180-200 mmHg (however vasodilation buffers this rise). during resistance-type exercise, can increase to 480 mmHg.

  • diastolic bp - stays the same during whole body continuous exercises, abnormal to increase more than 10 mmHg. but increases during resistance-type exercise, and can reach 350 mmHg.

5.3 - redistribution of blood flow

• involves the redirection of blood away from major organs and towards the working muscles through simultaneous vasodilation + vasoconstriction. measured in % of blood flow to muscles out of total blood flow

• purpose

  • vasodilation - blood vessels (capillaries + arterioles) expand in diameter → allows for increased blood flow.

  • vasoconstriction - blood vessels constrict (sphincters close?) → decreases blood flow.

  • at rest, 15-20% of total blood flow is directed to skeletal muscles. during exercise, blood vessels to working muscles vasodilate and blood vessels to major organs (such as digestive system, reproductive system) vasoconstrict, making 80-90% of total blood flow directed to working muscles. increased blood flow to working muscles allows for greater amount of blood delivered/transported for diffusion and use by working muscles for aerobic energy production

• purpose - increase of blood flow to working muscles (through redistribution) →

5.3 - redistribution of blood flow to skin (thermoregulation)

• thermoregulation - the process by which the body maintains it’s internal temperature of 37℃ despite changes in internal heat production or external environmental conditions.

• during exercise, heat is produced as a byproduct (among H₂O + CO₂) → thermoregulation aims to remove heat during exercise

• main heat loss mechanism - vasodilation of blood vessels near the skin, where heat can be released to the envrionment → helps cool the blood

• however, this causes a decrease in performance due to less blood being available for working muscles

5.3 - increased arteriovenous oxygen difference (a-VO2 Diff)

• a-VO2 Diff - the measure of the difference of the oxygen concentration in the arterial blood and venous blood, after the muscle is interfaced (a measure of oxygen utilisation by the muscles.) measured in mL of oxygen per 100 mL of blood.

• purpose

  • at rest, arterial O₂ concentration is 20mL/100mL, and venous O₂ concentration is 5mL/100mL → a-VO2 Diff of 5mL/100mL.

  • during exercise, arterial O₂ concentration stays at 20mL, but venous O₂ concentration decreases, because the muscles extract more O₂ from the blood. → a-VO2 Diff increases to 15-18mL/100mL, (~3x more than at rest)

5.4 - acute responses in the respiratory system

acute responses to exercise in the respiratory system

1. increased respiratory rate

2. increased tidal volume

3. increased ventilation

4. increased rate of pulmonary diffusion

5.4 - respiratory rate

• respiratory rate - the amount of breaths taken per minute, measured in bpm (not same as beats per minute)

  • at rest, bpm is often around 12. during exercise, can increase to 35-50 bpm (3-4 times more)

• purpose - increases the availability of oxygen that can be diffused into the bloodstream → increases oxygen delivery to the working muscles for aerobic energy production

5.4 - tidal volume

• tidal volume - the amount of O₂ (oxygen) breathed in or out in one breath, measured in litres

  • at rest, TV is often around 0.5L. during exercise, can increase to 3-5L (6-10 times more)

  • tidal volume is limited by the size of your lungs in your thoracic cavity → TV plateaus at a point

• purpose - in increase in TV increases the availability of oxygen that can be diffused into the bloodstream → increases oxygen delivery to the working muscles for aerobic energy production

5.4 - ventilation

• ventilation - amount of air inspired or expired per minute by the lungs, measured in litres (or litres/min??)

  • equation: ventilation = respiratory frequency x tidal volume. V = RF ⋅ TV

  • respiratory frequency contributes the greatest amount to an increase in ventilation as tidal volume plateus earelier

  • at rest, ventilation is around 5–6 litres per minute. during maximal exercise, it may increase beyond 180 litres per minute for males, and 130 litres per minute for females. this is 25 to 35 times greater than resting values

• purpose - increases the availability of oxygen that can be diffused into the bloodstream → increases oxygen delivery to the working muscles for aerobic energy production

5.4 - increased rate of pulmonary diffusion (+ gaseous exchange)

• pulmonary diffusion - the movement of oxygen and carbon dioxide from an area of high concentration to an area of low concentration

• purpose - pulmonary diffusion occurs via the alveolar-capillary interface

• after inspiration, oxygem ,oves from an area of high conc in the l

5.5 - acute responses from the muscular system

• increased motor unit recruitment

• increased a-VO2 Diff

• increased muscle temperature

• increased muscle enzyme activity

• decreased muscular substrate levels

5.5 - increased motor unit recruitment

• motor unit - includes sarcomere + neuron

• purpose - increased amount of motor units → increased muslce fibre recruitment + increased contraction force

5.5 - increased a-VO2 Diff

see cardiovascular flashcard

5.5 - increased muscle temperature

5.5 - increased muscle enzyme activity

5.5 - decreased muscular substrate levels