Learn Hardcore Norwegian: Jeg trener på et nytt treningssenter tre ganger i uken. - I work out at a new gym three times a week.

trene på [sted] = to train / work out at [place]
- Jeg trener på et treningssenter. = I work out at a gym.
på is the default preposition with many places/institutions:
på skolen (at school), på jobb (at work), på kontoret (at the office), på treningssenter (at the gym).

You can say Jeg trener. on its own, but then you’re not saying where you train, just that you train in general.

Can I say Jeg trener i et nytt treningssenter instead? What’s the difference between på and i here?

You can say i, and people will understand you, but:

på treningssenter = the usual, idiomatic way of saying at the gym.
i treningssenteret would emphasize being inside the building and sounds more literal, less idiomatic as a general statement about where you work out.

So for “I work out at a new gym”, Jeg trener på et nytt treningssenter is the most natural choice.

What exactly does trener mean? Is it “I train” or “I am training”?

Trener is the present tense of å trene (“to train / to exercise / to work out”).

Norwegian present tense covers both:

habitual:
Jeg trener på et nytt treningssenter tre ganger i uken.
= I work out at a new gym three times a week.
right now:
Jeg trener nå. = I’m working out now.

Norwegian usually doesn’t use a separate continuous form like “am training”; jeg trener covers both “I train” and “I am training” depending on context.

Why is it et nytt treningssenter and not en nytt treningssenter?

Because treningssenter is a neuter noun in Norwegian.

Indefinite article:
- en = common gender (masc./fem.)
  - en stol (a chair)
- et = neuter
  - et treningssenter (a gym / fitness center)
The adjective ny (new) must agree with the gender and number:
- en ny stol (a new chair – common gender)
- et nytt treningssenter (a new gym – neuter)
- nye stoler / nye treningssentre (new chairs / new gyms – plural)

So et nytt treningssenter is: et (neuter article) + nytt (neuter form of “new”) + treningssenter (neuter noun).

What does treningssenter literally mean? Is it just another word for “gym”?

Treningssenter is a compound:

trening = training, exercise
senter = center

So literally: training center / exercise center.

In practice it’s the normal neutral word for “gym / fitness center”.

Other words you might hear:

et gym / et treningsstudio – also used, especially for more “gym-like” places.
treningssenteret = the gym / the fitness center (definite singular).

Why is it tre ganger i uken? What does that literally mean?

Literally, tre ganger i uken is:

tre = three
ganger = times (plural of gang, “time/occasion”)
i = in
uken = the week (definite form)

So word-for-word: “three times in the week”, but it actually means “three times a week”.

You’ll also hear these variants:

tre ganger i uka – very common spoken/written Bokmål (more informal)
tre ganger per uke – “three times per week”, a bit more formal/neutral.

Why is it uken and not just uke?

Uken is the definite form: “the week”.

uke = a week (indefinite):
en uke – a week
uken = the week (definite):
den uken – that week / the week

The pattern is similar to other common-gender nouns:

en dag – dagen (a day – the day)
en uke – uken (a week – the week)

In this expression tre ganger i uken, Norwegian uses the definite form even though English says “a week”. It’s just a fixed pattern: [number] ganger i uken = “[number] times a week”.

What’s the difference between uken and uka?

Both mean “the week” in Bokmål; the difference is style/feel:

uken – more traditional / formal written Bokmål.
uka – more colloquial, matches how people usually speak.

So:

tre ganger i uken – perfectly standard; a bit more formal/neutral.
tre ganger i uka – very common in everyday speech and informal writing.

They’re interchangeable in meaning.

Could I move tre ganger i uken earlier in the sentence, like Jeg trener tre ganger i uken på et nytt treningssenter?

Yes, that’s grammatically correct, but the most natural order is usually:

Verb and object/complements
Place
Time/frequency

So:

Very natural: Jeg trener på et nytt treningssenter tre ganger i uken.
Also okay: Jeg trener tre ganger i uken på et nytt treningssenter.

In practice, Norwegian word order for adverbials is fairly flexible, but place before time is a common pattern when both are at the end.

Why is jeg written with a lowercase j? In English I is capitalized.

In Norwegian, personal pronouns are not capitalized in the middle of a sentence.

jeg = I
du = you
han / hun = he / she

They are only capitalized when they start a sentence, just like ordinary words:

Jeg trener på et nytt treningssenter.
In the middle of a sentence: … at jeg trener på et nytt treningssenter.

So a lowercase jeg is normal and correct.

Is there a way in Norwegian to emphasize that I’m training right now, like English “I am working out”?

Yes, you can make it more explicitly “right now” by using holder på å:

Jeg holder på å trene. = I am (in the middle of) working out.

But very often Jeg trener nå. with a time word (nå = now) is enough:

Jeg trener nå. Kan jeg ringe deg senere?
I’m working out now. Can I call you later?

In many contexts, Jeg trener. on its own can mean “I’m working out (right now)” if the situation makes that clear.

How do you pronounce Jeg trener på et nytt treningssenter tre ganger i uken?

A careful Bokmål pronunciation (one common variant) in IPA:

Jeg – /jæi/ or /jæ/
trener – /ˈtreːnər/
på – /poː/
et – /et/
nytt – /nyt/
treningssenter – /ˈtreːnɪŋsˌsɛntər/
(main stress on tré-, secondary on -sén-)
tre – /treː/
ganger – /ˈɡɑŋər/
i – /i/
uken – /ˈʉːkən/

Spoken quickly, words will link together:
Jeg trenerpå et nytt treningssenter tre gangeri uken.

Is treningssenter the usual way to say “gym”? Are there any common alternatives?

Yes, treningssenter is the standard neutral word for gym / fitness center.

Common alternatives:

et gym – shorter, a bit more informal, borrowed from English.
et treningsstudio – often used for more “studio-like” places.
på gymmet – “at the gym” (definite: gymmet = the gym).

Your sentence with a synonym:

Jeg trener på et nytt gym tre ganger i uken.
Jeg trener på et nytt treningsstudio tre ganger i uken.

All are understandable; treningssenter is the safest all-purpose choice.

How would I change the sentence to past or future tense?

The verb trene is regular:

Present: jeg trener – I train / I’m training
Preterite (past): jeg trente – I trained / I worked out
Present perfect: jeg har trent – I have trained / have worked out
Future (with skal): jeg skal trene – I will train / I’m going to work out

So your sentence becomes:

Past: Jeg trente på et nytt treningssenter tre ganger i uken.
Present perfect: Jeg har trent på et nytt treningssenter tre ganger i uken.
Future: Jeg skal trene på et nytt treningssenter tre ganger i uken.