anaerobic

an-air-OH-bik /ˌænəˈrəʊbɪk/
adjectiveC1TOEFLMCAT
technicalmedical

relating to, involving, or requiring an absence of free oxygen.

In exercise, this refers to short, intense bursts of energy (like sprinting or heavy lifting) where the body burns fuel without waiting for oxygen.

The story behind the word. Formed by adding the Greek prefix 'an-' (meaning 'without') to 'aerobic'. It was first used to describe bacteria that could live without air, and later applied to high-intensity exercise.

Word relationships

  • aerobic: Requiring free oxygen.

Commonly confused with

  • aerobic: Aerobic is 'with air'; anaerobic is 'without air'.

Collocations

  • anaerobic exercise
  • anaerobic threshold
  • anaerobic respiration

Example sentences

  • "Sprinting is an anaerobic activity that builds power and speed but can only be sustained for a short time." A description of high-intensity training.
  • "Anaerobic organisms can survive in environments like deep-sea vents where there is no oxygen." A biological context.

Memory hook

Anaerobic: 'An-Air'—No air. Without oxygen.

When not to use

Don't use it for jogging or long-distance swimming (those are aerobic).

Fun facts

  • Lactic acid is a byproduct of anaerobic metabolism, which is why your muscles 'burn' during a heavy set of weights or a sprint.

Related words

aerobic, metabolism

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