STARTER TASK HOMEWORK

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STARTER TASK HOMEWORK

• What type of contraction (isometric or isotonic)
  would the following exercises be using?
• Pushing against a scrummage machine in rugby.
• Pull-ups.
• Press-ups with the body held in the low position.
• A stalemate in arm wrestling.
• Kicking a ball.
• Hand to hand pushing across the chest.

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STARTER TASK ANSWERS

• Isometric
• Isotonic
• Isometric
• Isometric
• Isotonic
• Isometric

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PHYSICAL EDUCATION DEPARTMENT

• TRAINING EFFECTS

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LEARNING OUTCOMES

• Understand how and be able to explain through Q
  and A the short term effects of exercise.

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TRAINING EFFECTS 1

• Immediate short-term effects of exercise
• There are a number of physiological changes that
  take place in the body following the start of
  exercise.
• Many of these processes will have begun during
  the warm up and will be further accelerated
  during the high levels of activity in a
  competition.
• For your exam, you need to know about these
  short-term effects of exercise

muscles
circulation
Breathing
pulse rate
sweating.
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TRAINING EFFECTS 2

• Breathing
• As exercise starts, the rate of breathing rises
  quickly as the nervous system warns the body that
  exercise has begun.
• This will occur initially during warm up and
  again at the start of exercise proper.
• In some cases, the nervous system may kick in
  even before activity has commenced a sort of
  early warning system.

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TRAINING EFFECTS 3

• As the rate of breathing rises, more air is drawn
  into the lungs and the muscles involved in the
  act of breathing begin to work harder so that
  breaths become much deeper.
• Qs. What effect will this have on the body?
• The increased volume of air delivers more oxygen
  to the bloodstream in response to the demands of
  the working muscles.

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TRAINING EFFECTS 4

• Pulse Rate
• In response to this increased respiration level,
  the nervous system triggers a faster heart rate
  so that a greater volume of blood can be pumped
  around the body.
• The stroke volume remains constant but the
  increased heart rate delivers oxygen to the
  muscles at more than double its resting rate.
• The pulse and respiration rates will continue to
  rise until the volume of oxygen required by the
  working muscles is met.

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TRAINING EFFECTS 5

• The pulse rate will then level off as the body
  reaches a steady state of activity.
• In the case of purely anaerobic exercise (e.g.
  100 metres), these rates may continue to rise
  even after activity has ceased.

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TRAINING EFFECTS 6

• Circulation
• The circulation of blood increases as the level
  of activity rises in order to meet the increased
  demand of the muscles for oxygen.
• Although the major blood vessels dilate (become
  larger) to allow this to happen, there is a
  corresponding narrowing of those blood vessels
  not directly involved in the activity for
  example, those that supply the digestive system.
• This makes sure as much blood as possible gets to
  where it is most needed.

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TRAINING EFFECTS 7

• Muscles
• Blood vessels in the active muscles dilate in
  order to accommodate the increased blood flow
  generated by exercise.
• The blood temperature also rises, which is
  important, as this produces more efficient muscle
  action.
• A rise in blood temperature from 37? to 41?
  produces a 15 per cent increase in muscle
  performance.

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TRAINING EFFECTS 8

• This increase in temperature is also of benefit
  to the connective tissue at the points where the
  working muscles are attached to bone (muscle
  tendons).
• It increases their blood supply and greatly
  reduces the likelihood of tears, strains and
  muscle pulls during the early part of a
  performance.
• Much of this process will already have begun
  during the warm-up period.

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TRAINING EFFECTS 9

• Sweating
• Sweat is produced as a response to the normal
  build-up of body heat.
• This process is accelerated during increased
  levels of physical activity.
• Sweat is released through the sweat glands
  through the pores of the skin and is a means by
  which some waste products are removed from the
  body.
• It is also part of the process by which the body
  is cooled it contributes to a cooling of the
  surface of the skin and a constriction of the
  small blood vessels near its surface.

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HOMEWORK TASK

• What is the average pulse rate for a marathon
  runner during a race?
• What is the main reactions that occur in the
  muscles during exercise?
• How much water on average is lost through sweat
  whilst running a marathon?