undou no kouka wo sirabeta.

の links two nouns together. Here, 運動 modifies 効果, so 運動の効果 means the effect/effects of exercise.

A very literal breakdown is:

• 運動 = exercise
• 効果 = effect, benefit, result
• 運動の効果 = exercise’s effect / the effects of exercise

In English, we often translate this more naturally as the effects of exercise rather than exercise’s effects.

を marks the direct object of the verb. It tells you what was examined or investigated.

So in this sentence:

• 運動の効果 = the effects of exercise
• を = marks that as the thing being investigated
• 調べた = investigated / examined

So 運動の効果を調べた means (someone) investigated the effects of exercise.

Japanese normally puts the main verb at the end of the sentence. This is one of the basic differences from English.

So the structure is:

• 運動の効果 = object
• を = object marker
• 調べた = verb

A very literal word order would be: the effects of exercise + object marker + investigated

That may sound backwards in English, but it is normal in Japanese.

調べた is the past tense of 調べる.

• 調べる = to investigate / to examine / to look into
• 調べた = investigated / examined / looked into

So this sentence describes a completed action in the past: someone investigated the effects of exercise.

If you said 運動の効果を調べる, it would mean to investigate the effects of exercise or investigate(s) the effects of exercise, depending on context.

調べる is an ichidan verb (also called a る-verb).

Its basic forms are:

• dictionary form: 調べる
• past: 調べた
• negative: 調べない
• te-form: 調べて

So the change from 調べる to 調べた follows a very common pattern for ichidan verbs.

運動 often means exercise in everyday contexts, but it can also mean movement or even a campaign/movement in other contexts.

For example:

• in health/fitness: exercise
• in physics/general motion: movement
• in social/political contexts: movement or campaign

In 運動の効果を調べた, the most natural meaning is exercise, because effectiveness/benefits of exercise is a very common phrase.

Japanese nouns usually do not explicitly show singular vs. plural the way English does. So 効果 can be understood as effect or effects depending on context.

That means 運動の効果 could be translated as:

• the effect of exercise
• the effects of exercise
• the benefits of exercise

English chooses singular or plural based on what sounds most natural in context. Japanese often leaves that open.

Japanese often omits the subject when it is obvious, unimportant, or understood from context.

So 運動の効果を調べた does not say who investigated it. Depending on context, it could mean:

• I investigated the effects of exercise
• We investigated the effects of exercise
• They investigated the effects of exercise
• Someone investigated the effects of exercise

This is very normal in Japanese. You only add the subject if it is needed.

Yes. You can add a subject or topic if needed.

For example:

• 私は運動の効果を調べた。 = I investigated the effects of exercise.
• 彼が運動の効果を調べた。 = He investigated the effects of exercise.

Very roughly:

• は marks the topic
• が marks the grammatical subject, often with a sense of identification or emphasis

But without context, leaving the subject out is perfectly natural.

調べた is a broad verb. It can mean investigated, examined, looked into, or checked, depending on context.

In this sentence, natural translations include:

• investigated the effects of exercise
• examined the effects of exercise
• looked into the effects of exercise

Compared with some similar verbs:

• 調べる = to investigate, examine, check
• 研究する = to research, study academically
• 確認する = to confirm, check
• 調査する = to investigate formally, survey

So 調べた is a flexible, everyday verb and works well here.

Japanese does not have articles like a, an, or the. Whether something is the effect, an effect, or the effects is understood from context.

So 運動の効果を調べた can be translated naturally into English with an article even though Japanese does not contain one explicitly.

This is very common. When translating Japanese into English, you often have to decide:

• whether to use a/an or the
• whether to use singular or plural

Yes, that can be a natural English interpretation depending on context.

Literally, 運動の効果を調べた is about investigating the effects/benefits of exercise, but in smoother English that may become:

• I looked into how effective exercise is.
• I examined the benefits of exercise.
• I investigated the effects of exercise.

So the exact English wording may change, even though the Japanese stays the same.

Yes. It is short, but completely natural.

Japanese often allows short sentences like this, especially when the subject is already known. In a conversation, report, or narration, this would sound normal.

If you wanted to make it more explicit, you could expand it, for example:

• 私は運動の効果を調べた。 = I investigated the effects of exercise.
• 研究者たちは運動の効果を調べた。 = The researchers investigated the effects of exercise.

But the original sentence is already grammatically complete.