1 C1 informal
To increase muscle mass through physical training.
"He spent six months muscling up in the gym before the bodybuilding competition."
inseparable
muscle up
C1 informal inseparable intransitive
To build up physical muscle mass through exercise, or to gather the strength or resolve to do something.
In plain English
To build bigger muscles, or to get strong enough to do something hard.
What does "muscle up" mean?
2 meanings, ordered from most common to least. Color-coded by CEFR level.
2 C1 idiomatic informal
To gather strength, courage, or resources in preparation for a difficult task.
"The small nation had to muscle up diplomatically to resist the pressure."
inseparable
Literal vs figurative
Words literally mean
To build up one's muscles — largely transparent.
Actually means
To build bigger muscles, or to get strong enough to do something hard.
Usage tip
Used in fitness contexts to mean building muscle. Also used figuratively to mean summoning strength or determination for a challenge. More common in American English than British.
Words that pair with "muscle up"
Natural word combinations native speakers use most often.
gym training strength challenge competition arms
How to conjugate "muscle up"
The five tense forms you'll use most often.
Base
muscle up
I/you/we/they
3rd person
muscles up
he/she/it
Past simple
muscled up
yesterday
Past participle
muscled up
have + pp
-ing form
muscling up
continuous
Hear "muscle up" in the wild
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