Если я бегаю каждый день, я становлюсь крепче.

In Russian, this sentence expresses a general truth or habitual cause-and-effect relationship:

• Если я бегаю каждый день = if I run every day / when I run every day
• я становлюсь крепче = I become stronger

Russian commonly uses the present tense in both parts of this kind of sentence when talking about something that is regularly true. It is not a future conditional here; it is more like:

• Whenever I run every day, I get stronger
• If I run every day, I get stronger

So the present tense sounds completely natural.

This is a very common question because both forms come from бегать / бежать and both can relate to running.

Here, бегаю is used because it means I run regularly / I go running / I am in the habit of running.

• бегаю = repeated, habitual, non-directional activity
• бегу = I am running right now, in one specific instance, usually in one direction

Since каждый день means every day, the sentence clearly talks about a repeated habit, so бегаю is the correct choice.

Compare:

• Я бегаю каждый день. = I run every day.
• Я бегу в парк. = I’m running to the park.

Каждый день uses the accusative case.

Why? Because expressions of duration or repeated time periods often use the accusative in Russian.

So:

• каждый is the masculine accusative form
• день here looks the same as nominative because it is an inanimate masculine noun, and inanimate masculine accusative = nominative

This phrase simply means every day.

Other similar examples:

• каждую неделю = every week
• каждый месяц = every month
• каждый год = every year

Становлюсь comes from становиться, which means to become.

So the structure is:

• я становлюсь крепче = I become stronger / I am getting stronger

You need a verb here because Russian is expressing a change of state, not just a state.

• Я крепче by itself would sound incomplete or unnatural in this meaning.
• Я сильный = I am strong
• Я становлюсь сильнее / крепче = I am becoming stronger

So становлюсь tells us that something changes as a result of the running.

The -сь is the reflexive ending of the verb становиться.

In Russian, many verbs are reflexive, and становиться is the normal verb for become. The non-reflexive становить usually means something else, like to place / to set / to install, depending on context.

So:

• становиться = to become
• становлюсь = I become / I am becoming

You should learn становиться as a whole verb, not as становить + something extra in this sentence.

Крепче is the comparative form of крепкий.

• крепкий = strong, sturdy, robust
• крепче = stronger

After становиться, Russian very often uses a comparative when talking about gradual change:

• становиться лучше = become better
• становиться хуже = become worse
• становиться сильнее = become stronger
• становиться крепче = become stronger / tougher / more robust

So the sentence is not saying I become strong in an absolute sense, but I become stronger relative to before.

Крепче and сильнее can both be translated as stronger, but they are not always identical.

• сильнее comes from сильный and usually focuses more directly on strength, power, force
• крепче comes from крепкий and can suggest physical robustness, sturdiness, toughness, solidity, better health

In this sentence, крепче sounds natural if you mean that running makes your body more robust or fit. A Russian speaker could also say:

• Если я бегаю каждый день, я становлюсь сильнее.

That would also be correct, but it may emphasize strength a bit more directly.

Yes, in sentences like this, если often feels close to if or when/whenever in English.

Because the sentence describes a regular truth, the meaning is something like:

• If I run every day, I get stronger
• Whenever I run every day, I get stronger

So even though если literally means if, the overall sense can be broader in habitual statements.

Russian normally uses a comma between the two parts of a complex sentence when one clause depends on the other.

Here:

• Если я бегаю каждый день = subordinate clause
• я становлюсь крепче = main clause

So the comma is required:

• Если я бегаю каждый день, я становлюсь крепче.

This is standard Russian punctuation.

Yes. Russian word order is fairly flexible, though some versions sound more neutral than others.

The most neutral version is:

• Если я бегаю каждый день, я становлюсь крепче.

You could also say:

• Я становлюсь крепче, если я бегаю каждый день.

That still means the same thing, but the focus shifts slightly toward the result first.

You could even emphasize каждый день differently in speech, but the original version is the clearest and most natural for learners.

Yes, Russian often repeats the subject pronoun for clarity, especially in a sentence with two clauses.

So:

• Если я бегаю каждый день, я становлюсь крепче.

sounds completely normal.

Sometimes Russian can omit pronouns when the meaning is obvious, but in a sentence like this, repeating я is natural and helps keep the structure clear. Leaving out the second я is possible in some contexts, but the full version is better and more standard for a simple statement like this.