GCSE PE UNIT 1c - aerobic and anaerobic exercise

• Aerobic exercise is…

  “Exercise that requires energy supplied by the breaking down

  of food (glucose) using oxygen.”

  Aerobic exercise is usually performed at low to moderate levels

  of intensity. This allows the body to use oxygen to break down

  glucose supplies from our food, allowing the muscles to

  continually contract and create continuous movement.

  As a result, water and carbon dioxide are created as waste

  products.
• Anaerobic exercise is…

  “Exercise that requires energy in the absence of oxygen.”

  Anaerobic exercise is usually performed at high levels of

  intensity for a short duration of time. The body does not have

  time to use oxygen as an energy source, which means glucose is

  not fully broken down, so carbon dioxide and water cannot be

  produced.

  As a result, the glucose is converted into lactic acid while energy

  is produced to complete the activity.
• Lactic acid is a major cause of fatigue. This makes it very difficult to

  perform anaerobic exercise for long periods of time – usually limited to

  one minute or under.

  The build up of lactic acid in the muscles causes fatigue and eventually

  pain, causing the performer to slow down or even stop performing.
• Excess Post-Exercise Oxygen Consumption (EPOC) occurs immediately

  following strenuous exercise, usually following the performance of an

  anaerobic activity.

  As the body has been working hard, breathing becomes heavy and

  extra oxygen is inhaled in order to repay the oxygen debt.

  The duration of strenuous activity, along with the intensity of the

  activity itself, determines the length of time oxygen debt will last as

  this will have affected the amount of lactic acid produced.
• Immediate effects of exercise


  Symptoms seen or felt by a performer whilst exercise is taking place
• Body's adaptation to exercise

  1. Increase in demand for oxygen

  2. Heart rate increases

  3. Stroke volume increases

  4. Breathing rate increases

  5. Tidal volume increases
• Normal resting heart rate

  • 70-80 beats per minute
• Exercise heart rate


  • 100-150 beats per minute
• Heart rate increases


  Stroke volume increases
• Breathing rate increases


  Tidal volume increases
• Increased tidal volume allows for greater gas exchange in the lungs so more oxygen can be inhaled to supply the working muscles
• Short term effects of exercise

  Effects seen or felt in the time period of between 24 and 36 hours following exercise
• Short term effects of exercise

  • Fatigue or muscle tiredness which normally clear after a day or two
  • Light headedness - feeling faint or dizzy can be caused by a lack of blood sugar or a drop in blood pressure, often after heavy sweating
  • Nausea - feeling sick or actually vomiting may be caused by over-exerting yourself or from not consuming enough water
  • DOMS - Delayed onset of Muscle Soreness, the pain and stiffness often felt after strenuous exercise, from torn muscle fibres that have swollen and are in a state of repair, which is actually a benefit of exercise as following the repair, the muscle becomes stronger
  • Cramp - a painful involuntary contraction of the muscle, often caused by fatigue or dehydration
• is extremely important for athletes to consider time for

  recovery immediately following bouts of vigorous exercise.

  This will help the athlete to avoid excessive problems with

  short-term effects of exercise, such as nausea, fatigue and/or

  DOMS.
• When? Used by athletes immediately following vigorous exercise.

  Why? To prevent the onset of DOMS and speed up recovery following

  exercise.

  How? The freezing cold water constricts the blood vessels and flushes the

  waste products such as lactic acid out of the affected tissues, while also

  reducing swelling. Once out of the water, the body starts to warm up,

  meaning the increased blood flow to the muscles helps the healing process.
• Cool Down

  When? Used by athletes immediately following exercise.

  Why? To prevent the onset of DOMS, reduce effects of nausea,

  and allows breathing rate to return to normal following exercise.

  How? 5 to 10 minutes of jogging or light exercise helps to

  decrease the body temperature and remove waste products such

  as lactic acid from the muscles. 5 to 10 minutes of static stretching

  should then be completed to help relax the working muscles.
• Manipulation of Diet

  When? Immediately following exercise.

  Why? To replenish lost fluids through sweating and energy used during

  exercise.

  How? Glucose and minerals (water) are replaced through consumption

  of water and foods high in carbohydrates. Flavoured milk or

  meal-replacement drinks are popular among athletes as a combined

  source of fluids and glucose in order to manipulate the body into

  replacing stored energy at a quicker rate.
• When? Immediately following exercise.

  Why? To reduce DOMS, muscle soreness, muscle swelling or pain

  following exercise.

  How? By rubbing and manipulating muscles and joints using your

  hands. Most elite athletes will have access to a physiotherapist who

  can perform the massage for the athlete, however amateur athletes

  would need to perform this on themselves or access professional

  support in their own time.
• More specifically, the long-terms effects may include:

  Change in body shape.

  Improved fitness, including strength, speed, muscular

  endurance, suppleness (flexibility) and cardiovascular

  endurance.

  Increased size of the heart (hypertrophy).

  Lower resting heart rate (bradycardia).
• Change in Body Shape

  Regular exercise will normally result in weight loss as the

  body uses fat stores for energy.

  Additional muscle mass may also be gained if exercise is

  anaerobic, which is known as hypertrophy.
• Improved Components of Fitness

  Different components of fitness can be developed depending on the type of

  exercise completed. For example:

  Repetitive movement exercise, such as lunges or sit ups, will develop

  your muscular endurance;

  Anaerobic lifting of weights will develop your muscular strength;

  Rapid anaerobic movements, such as sprinting, will increase your speed;

  Slower, more aerobic movements, such as running or swimming, will

  develop cardiovascular endurance.
• Increased size of the heart

  Following a training program for a long period of time will

  result in benefits for your heart function. This is due to the

  heart beating faster than normal for a long period of time.

  As the heart is a muscle, this will increase the size of the

  heart, so hypertrophy of the heart occurs.
• Lower resting heart rate

  Despite the heart increasing in size, the amount of blood pumped around the

  body (cardiac output) remains the same as blood is not created through

  exercise.

  However, stroke volume does increase as the heart is now more efficient at

  pumping the blood around the body.

  As a result, your heart rate will adapt to ensure it maintains the same resting

  cardiac output, so your heart rate reduces.

  This reduction in heart rate is known as bradycardia and normally occurs

  after years of regular training.