ENGLISH
REFERENCE

bulk up

phr. v..
B2 Upper Intermediate Oxford

phr. v.. to make your body bigger and stronger by gaining muscle, usually through exercise and eating more.

phr. v.. to increase one's body mass, specifically muscle tissue, through a combination of hypertrophy-focused resistance training and caloric surplus.


SIMPLE

He wants to bulk up before the rugby season starts.

CONTEXTUAL

After months of lifting heavy weights and eating extra protein, the athlete managed to bulk up significantly.

COMPLEX

The actor was required to bulk up for his role as a superhero, undergoing a rigorous six-month physical transformation under professional supervision.

Particles
up
Separability
optional
Pattern
bulk + up (+ object)
Usage

often used as an intransitive verb, but can be used transitively when referring to a specific part of the body.

Teaching tip

contrast with 'slim down' or 'tone up'; 'bulk' implies a significant increase in size and volume rather than just definition.

Pitfall

He bulks up his muscles.He is bulking up.while 'bulk up' can take an object, it is most commonly used as an intransitive verb to describe the person's overall physical change.

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