Aerobic vs Anaerobic Exercise and Recovery
The difference between aerobic and anaerobic exercise, their word equations, why lactic acid causes fatigue, and how the body repays the oxygen debt to recover.
Justify the choices, the way you are assessed
Free interactive practice on the decisions the assessment actually asks you to justify.
Start revising freeWhat you'll cover
With and without oxygen
Your muscles need energy to keep moving. In long, steady exercise the body has time to use oxygen to release energy. In short, very hard exercise there is not enough oxygen, so the body releases energy a different way and makes a waste product. This module looks at aerobic and anaerobic exercise, their word equations, and how the body recovers.
Aerobic and anaerobic terms
Learn these four terms before you study aerobic and anaerobic exercise.
Aerobic vs anaerobic
Aerobic and anaerobic exercise suit different kinds of activity.
Drill the two equations
Under exam pressure it is easy to swap the two word equations, so drill them until they are automatic. Only aerobic exercise uses oxygen and makes carbon dioxide and water. Anaerobic exercise makes lactic acid instead. After hard exercise, keep breathing deeply and cool down so the extra oxygen can repay the oxygen debt and remove the lactic acid.
Match the term
- aerobic exercise
- anaerobic exercise
- lactic acid
- oxygen debt
- exercise that uses oxygen to release energy
- hard exercise that works without enough oxygen
- the waste product that builds up and causes muscle fatigue
- the extra oxygen needed after exercise to recover
Match the activity
- running a marathon
- a 100 metre sprint
- a gentle jog
- one heavy weight lift
- a long steady race fuelled mainly by aerobic exercise
- a short fast race fuelled mainly by anaerobic exercise
- easy exercise the body can keep fuelling with oxygen
- one short powerful effort with too little oxygen
What is anaerobic exercise?
What is anaerobic exercise?
- Hard exercise that works without enough oxygen and produces lactic acid.
- Steady exercise that uses plenty of oxygen over a long time.
- Gentle stretching done only as a warm up before sport.
- Slow exercise done to recover after a race.
Spot the anaerobic activities
Select the TWO activities that are mainly anaerobic exercise.
- Sprinting flat out for 100 metres.
- Lifting a heavy weight once.
- Jogging steadily for an hour.
- Swimming slowly for 30 minutes.
Order the recovery
Put the steps of recovering from hard anaerobic exercise in order, earliest first.
- You stop the hard anaerobic exercise
- You keep breathing deeply and your heart keeps beating fast
- The extra oxygen repays the oxygen debt
- The lactic acid is broken down and removed
Complete the equations
Aerobic exercise uses oxygen. Its word equation is glucose plus _____ produces energy plus carbon dioxide plus _____. Anaerobic exercise happens without enough oxygen. Its word equation is glucose produces energy plus _____ acid. Aerobic exercise suits _____ steady effort, while anaerobic exercise suits short bursts of _____ effort.
Find the aerobic zone
The aerobic training zone is 60% to 80% of maximum heart rate, and maximum heart rate is 220 minus age. What is the upper limit of the aerobic zone for a 15-year-old, in beats per minute?
Tap the anaerobic activities
Tap the TWO activities that are mainly anaerobic exercise.
- Running a marathon
- A 60 metre sprint
- A gentle cycle to school
- One maximum weight lift
- A slow warm up jog
Aerobic or anaerobic?
Decide whether each activity is mainly aerobic or mainly anaerobic exercise.
- A steady five kilometre run at an easy pace
- A single all-out ten second sprint
- A long slow swim lasting forty minutes
Explain the exercise
A footballer sprints hard during a match and feels tired straight afterwards. Explain why sprinting is anaerobic exercise, and describe how the body recovers once the sprint is over.
- Explain what anaerobic exercise means
- Explain why sprinting is anaerobic and what lactic acid does
- Describe how the body repays the oxygen debt to recover