French Phrase
Ça bosse tes biceps et tes avant-bras.
Meaning
Literally, ‘That works your biceps and your forearms.’ In everyday French it’s a slang way of saying that an exercise or activity is effective for building the biceps and forearm muscles.
When to use
Use this sentence when you’re talking about a workout, a piece of equipment, or any movement that targets the upper‑arm and forearm muscles. It’s informal, so it fits casual conversation with friends or gym‑buddies, not a formal fitness class description.
✦Grammar Breakdown
Çabossetesbicepsettesavant-bras.
Ça
Demonstrative pronoun meaning 'that' or 'it', used informally to refer to a situation or activity.
bosse (verb)
Third‑person singular of the verb *bosser* used colloquially to mean ‘to work out, to be effective for a muscle’.
tes
Possessive adjective for ‘your’ (plural or singular nouns) used before a noun that is not preceded by an article.
biceps
Masculine plural noun for the upper arm muscle; stays the same in singular and plural.
avant-bras
Masculine plural noun meaning ‘forearm’; the hyphenated form is standard.
et
Coordinating conjunction meaning ‘and’.
🗨In Conversation
Ça bosse tes biceps et tes avant-bras.
It works your biceps and forearms.
Oui, j’ai senti la différence après les tractions.
Yes, I felt the difference after the pull‑ups.
✕Common Mistakes
C’est bosse tes biceps.
‘C’est bosse’ mixes the verb *bosser* with the wrong auxiliary; the correct form is *ça bosse* (subject‑verb agreement).
Je bosse les biceps chaque jour.
When you want to say ‘to work out the biceps’, you normally use *bosser* without an object, e.g., *Ça bosse les biceps* is acceptable, but *bosser les biceps* alone sounds like ‘to work the biceps (as a job)’. Use *travailler* or *solliciter* for a neutral tone.
Ça bosse tes avant bras.
The hyphen is required; writing *avant bras* is considered a spelling error.
↔Alternatives
Cela travaille tes biceps et tes avant-bras.
That trains your biceps and forearms.
Ça fait travailler tes biceps et tes avant-bras.
It makes your biceps and forearms work.
Cet exercice sollicite tes biceps et tes avant-bras.
This exercise targets your biceps and forearms.
Cultural Tip
The verb *bosser* originally means ‘to work (a job)’, but in youth and gym slang it’s often used to describe an activity that ‘gets the muscles working’. It’s perfectly natural in spoken French, especially among younger speakers, but you’ll want to avoid it in formal writing or when speaking to a trainer you don’t know well.