Learn Hardcore Indonesian: Saya mempelajari pengaruh cuaca buruk pada latihan kebugaran. - I study the effect of bad weather on fitness training.

What is the difference between mempelajari and belajar in this sentence? Could I say Saya belajar pengaruh cuaca buruk pada latihan kebugaran instead?

Mempelajari and belajar are related but not interchangeable in all contexts.

belajar = to learn / to study (in general). It is often intransitive (no direct object) or takes a simple field of study:
- Saya belajar. = I am studying / I study.
- Saya belajar bahasa Indonesia. = I study Indonesian.
mempelajari = to study something in detail, to examine, to research. It is transitive and normally followed by a more complex object:
- Saya mempelajari pengaruh cuaca buruk pada latihan kebugaran.
  I study/examine the influence of bad weather on fitness training.

Saya belajar pengaruh cuaca buruk… sounds unnatural. If you want to use belajar, you should add tentang:

Saya belajar tentang pengaruh cuaca buruk pada latihan kebugaran.

That is acceptable and a bit more conversational.
The original with mempelajari sounds more formal and research‑like, as in an academic or scientific context.

In the phrase pengaruh cuaca buruk pada latihan kebugaran, which word is the main noun, and how is the phrase put together?

The head (main noun) of the phrase is pengaruh.

The structure is:

pengaruh = influence / effect (head noun)
cuaca buruk = bad weather (noun + adjective) → specifies whose influence:
pengaruh cuaca buruk = the influence of bad weather
pada latihan kebugaran = on fitness training (prepositional phrase) → tells you what is affected

So the whole object is:

pengaruh (influence)
[cuaca buruk] (of bad weather)
[pada latihan kebugaran] (on fitness training)

In other words: mempelajari [pengaruh X pada Y] = study the influence of X on Y.

Why do we use pada before latihan kebugaran instead of di, kepada, or terhadap?

The choice of preposition changes the nuance:

pada
Often used in formal Indonesian to mean on / upon / in relation to something, including abstract targets:
- pengaruh cuaca buruk pada latihan kebugaran
  = the influence of bad weather on fitness training
  This is the most natural choice here.
di
Usually indicates a physical location (in, at, on):
- di rumah (at home), di Jakarta (in Jakarta)
  Pengaruh cuaca buruk di latihan kebugaran would sound like “the influence of bad weather in the fitness training (place)” and feels odd in this meaning.
kepada
Used mainly with people or animate recipients:
- mengajar kepada siswa (to teach to students)
- berbicara kepada guru (to talk to the teacher)
  It’s not natural with latihan kebugaran, which is an activity, not a person.
terhadap
Means toward / on / with respect to, usually formal and often used for attitudes or effects:
- sikap masyarakat terhadap pemerintah
- dampak polusi terhadap kesehatan
  You could say:
- pengaruh cuaca buruk terhadap latihan kebugaran
  This is also correct and sounds quite formal, maybe a little more “heavy” than pada.

In short, pada is the standard, natural choice for “the effect on something” in this sentence.

What exactly does pengaruh mean here, and how is it different from words like efek or dampak?

In this sentence, pengaruh means influence / effect in a fairly neutral way.

Comparison:

pengaruh
Neutral, common word for influence or effect:
- pengaruh kopi pada tidur = the effect of coffee on sleep
  Works in everyday speech and in formal writing.
efek
Loanword from effect (English) / effet (other languages), common in scientific or technical contexts:
- efek samping obat = side effects of medicine
  You could say:
- Saya mempelajari efek cuaca buruk pada latihan kebugaran.
  This is fine, a bit more “technical”.
dampak
Often translated as impact, usually stronger and often negative:
- dampak bencana alam
- dampak negatif media sosial
  With your sentence:
- dampak cuaca buruk pada latihan kebugaran
  suggests more serious or harmful consequences on training.

So pengaruh is a good neutral choice for general “influence/effect” without stressing it as strongly negative or technical.

Why is it cuaca buruk and not buruk cuaca? Is the adjective always after the noun in Indonesian?

In Indonesian, descriptive adjectives normally come after the noun they modify.

cuaca buruk = bad weather
buku baru = new book
film menarik = interesting film

So cuaca buruk is the regular, grammatical order.
buruk cuaca would be wrong in normal Indonesian and sounds like a mistake.

There are some special cases:

Certain fixed expressions where the first word is not really an adjective anymore:
- orang tua = parents (literally “old person”)
- orang gila = crazy person
A few poetic or emphatic inversions, but those are rare and stylistic.

As a general rule for learners:
Noun + Adjective is the normal order in Indonesian.

What does latihan kebugaran literally mean, and is it the same as saying exercise or working out in English?

Literally:

latihan = training, practice
kebugaran = fitness (from bugar = fit/healthy)

So latihan kebugaran literally means fitness training.

In terms of meaning, it is close to:

exercise
working out
fitness training / workout sessions

Other common ways to talk about similar things:

olahraga = sport / exercise in general
- Saya berolahraga setiap hari. = I exercise every day.
latihan fisik = physical training
fitnes (from English fitness, often spelled fitness or fitnes)
- latihan fitness di gym = workout at the gym

Latihan kebugaran sounds fairly neutral to formal, and fits well in written or academic contexts like the sentence you gave.

How do I know whether this sentence means I study, I am studying, or I studied? Indonesian verbs don’t change form, so what is the tense here?

Indonesian verbs do not change form for tense. Mempelajari is the same for past, present, and future. The tense is understood from context or from time markers.

Your sentence:

Saya mempelajari pengaruh cuaca buruk pada latihan kebugaran.

Without any context, it could mean:

I study (habitually)
I am studying (currently, in general)
I studied (in the past, if the surrounding context makes that clear)

You can make the time clearer by adding adverbs:

Saya sedang mempelajari… = I am (currently) studying…
Tadi saya mempelajari… = Earlier I studied…
Kemarin saya mempelajari… = Yesterday I studied…
Saya akan mempelajari… = I will study…

So grammatically the verb has no tense; you add context words like sedang, tadi, kemarin, akan, etc. to specify time.

Why is saya used here, and when would I use aku instead?

Both saya and aku mean I, but they differ in formality and context.

saya
- Polite, neutral
- Used with strangers, in formal situations, with older people, in business, and in writing (articles, reports, etc.)
- Fits very well in an academic‑style sentence like:
  - Saya mempelajari pengaruh cuaca buruk pada latihan kebugaran.
aku
- Informal / intimate
- Used with close friends, family, people of the same age group in casual conversation
- The same sentence in a casual context could be:
  - Aku mempelajari pengaruh cuaca buruk pada latihan kebugaran.

Using aku in a formal report or speaking to someone much older can sound too casual or childish. Using saya is almost always safe in neutral or formal situations.

Can I omit saya and just say Mempelajari pengaruh cuaca buruk pada latihan kebugaran? Would that still be correct?

You can omit saya in some contexts, but it changes how the phrase is interpreted.

As a normal spoken or written sentence, Indonesian usually expects a subject:
- Saya mempelajari pengaruh cuaca buruk pada latihan kebugaran.
  = clear, complete sentence.
Without saya, Mempelajari pengaruh cuaca buruk pada latihan kebugaran feels like:
- a title or heading
- a bullet point
- the -ing form in English: Studying the influence of bad weather on fitness training

For example, as a thesis title:

Mempelajari Pengaruh Cuaca Buruk pada Latihan Kebugaran

That is fine.
But if you are just stating what you are doing in normal prose or conversation, you normally include saya (or aku).

How could I say the same idea in a more casual, everyday Indonesian style?

Here are a couple of more casual options:

Moderately casual (still quite correct and clear):
- Aku lagi belajar tentang pengaruh cuaca buruk pada latihan kebugaran.
  - aku = informal “I”
  - lagi = currently (similar to “am …‑ing”)
  - belajar tentang = learn about / study
Very conversational / spoken style:
- Aku lagi cari tahu gimana cuaca jelek ngaruh ke latihan olahraga.
  - cari tahu = find out
  - gimana = how (colloquial for bagaimana)
  - cuaca jelek = bad weather (more casual than cuaca buruk)
  - ngaruh = slangy form of berpengaruh (to affect)
  - latihan olahraga = workout / exercise

The original sentence is quite formal and suitable for academic or written contexts; the versions above sound more like everyday speech among friends or classmates.

What is the root of mempelajari, and what do the prefix me- and the suffix -i do?

The ultimate root is ajar (to teach), but the immediate base form is pelajar.

Morphology:

ajar = teach (root)
pelajar = student; also part of the verb base pelajari
mempelajari = meN‑ + pelajar + ‑i

Components:

meN‑ (here realized as mem‑)
A common verbal prefix that usually makes an active verb.
‑i
A suffix that often means the action is directed towards something or done to an object repeatedly/in detail.

So mempelajari roughly means:

to actively apply oneself to study/examine something in detail.

Related words from the same root:

mengajar = to teach (someone)
belajar = to learn
pelajar = student
pelajaran = lesson

Knowing this family of words helps you see the connection between ajar, belajar, mengajar, and mempelajari.