Learn Hardcore Russian: Если пропускать разминку, мышцы устают быстрее и осанка портится. - If you skip the warm‑up, the muscles get tired faster and your posture gets worse.

Если пропускать разминку… literally: “If (one) skip the warm‑up…”
The implied subject is “you / one / people in general”, but it’s not said out loud.

This structure is common in:

Instructions: Курить запрещено. – Smoking is forbidden.
General statements: Если много работать, можно устать. – If you work a lot, you can get tired.

So the sentence is more like: “If you (in general) skip the warm‑up…”, not about one specific person, but about people in general.

Could we say Если ты пропускаешь разминку instead of Если пропускать разминку? What’s the difference?

Yes, both are grammatically correct, but they feel slightly different:

Если пропускать разминку, мышцы устают быстрее…
- Very general, impersonal rule.
- Sounds like something from a health article, textbook, or general advice.
Если ты пропускаешь разминку, мышцы устают быстрее…
- Directly addressed to a specific person (you).
- Sounds more conversational, like a trainer or friend talking to you.
You can also hear: Если будешь пропускать разминку, мышцы будут уставать быстрее…
- More clearly about the future and about repeated behavior.
- Similar to: “If you keep skipping the warm‑up…”

All three are correct; the original version is just the most impersonal, generic one.

Why is it пропускать and not пропустить? What’s the difference between these two?

Пропускать and пропустить are the imperfective vs. perfective pair:

пропускать (imperfective) – to skip in general, to be in the habit of skipping, to be skipping (process or repeated action).
пропустить (perfective) – to skip once, to have skipped (a single completed action).

In this sentence, we’re talking about a habitual / repeated action:

Если пропускать разминку…
= If someone regularly / generally skips warm‑ups…

Saying Если пропустить разминку… would sound like:

“If you happen to skip the warm‑up (one single time)…”
That’s more about one specific event, not a general rule. The author wants a general health rule, so пропускать is correct.

What case is разминку in, and why?

Разминку is in the accusative singular case.

The dictionary form is разминка (feminine, nominative singular).
The verb пропускать takes a direct object in the accusative:
- пропускать что? – to skip what? → разминку.

Pattern:

Nominative: разминка
Accusative: разминку (as a feminine inanimate noun ending in -а → -у)

So the structure is:

пропускать (что?) разминку – to skip the warm‑up.

Can you explain the verb устают? Why is it in the present tense and plural?

Устают is:

3rd person plural
present tense
imperfective
from the verb уставать – to get tired.

Plural
It agrees with мышцы (muscles), which is plural:
- мышцы устают – muscles get tired.
Present tense for general truth
Russian often uses the present tense for general truths and regular results, where English might use “get / will get”:
- Мышцы устают быстрее.
  Literally: Muscles get tired faster.
  In context: Muscles (will) get tired faster.

If you said мышцы устанут быстрее (future perfective), it would sound more like one specific situation: “The muscles will get tired faster (this time).” The original sentence is about a general rule, so the present устают is natural.

Can we change the word order in мышцы устают быстрее? For example: мышцы быстрее устают or быстрее устают мышцы?

Yes, Russian word order is fairly flexible. All of these are grammatically correct:

Мышцы устают быстрее.
Мышцы быстрее устают.
Быстрее устают мышцы.

Differences are mostly about emphasis:

Мышцы устают быстрее. – neutral: Muscles get tired faster.
Мышцы быстрее устают. – slight emphasis on “faster”.
Быстрее устают мышцы. – stronger emphasis on “faster”; might answer a question like:
– Что происходит быстрее? – What happens faster?
– Быстрее устают мышцы. – The muscles get tired faster.

In normal neutral speech, мышцы устают быстрее or мышцы быстрее устают are the most common.

What exactly is быстрее here? Is it an adverb or an adjective, and how is it formed?

Быстрее is the comparative form of быстрый (fast).

For the base adjective быстрый:

Positive: быстрый – fast
Comparative: быстрее – faster
Superlative: самый быстрый – the fastest

In this sentence:

мышцы устают быстрее
→ the muscles get tired faster

Here быстрее functions like an adverb modifying the verb устают (get tired), answering “How do they get tired?” → faster.

You could also use the analytical form более быстро (“more quickly”), but быстрее is shorter and more natural in everyday speech.

What does портится mean, and how is it related to портить?

Портится is the reflexive form of the verb портить.

портить (что?) – to spoil / damage / ruin something
- портить осанку – to ruin (someone’s) posture
портиться – to get spoiled / to go bad / to deteriorate (by itself)
- осанка портится – posture gets worse / deteriorates

So:

портить is transitive (you do something to something).
портиться is intransitive / reflexive, and often corresponds to an English “get/become + adjective”:
- молоко портится – the milk goes bad
- отношения портятся – the relationship is deteriorating
- осанка портится – posture is getting worse

In this sentence, осанка портится means “your posture gets worse”, not that someone actively “spoils” it at that moment.

Why is it осанка портится (singular) but мышцы устают (plural)?

This is just normal subject–verb agreement:

мышцы – plural noun → verb in plural:
- мышцы устают – the muscles get tired.
осанка – singular noun → verb in singular:
- осанка портится – posture gets worse.

So the pattern is:

[Plural subject] + [plural verb]
[Singular subject] + [singular verb]

There’s no special rule here; each verb agrees with its own subject:

мышцы устают
осанка портится

Why is there a comma after Если пропускать разминку?

In Russian punctuation, a clause introduced by если (if) is a subordinate conditional clause, and it is normally separated by a comma from the main clause.

Structure:

Если пропускать разминку, – subordinate clause (condition)
мышцы устают быстрее и осанка портится. – main clause (result)

Rule:
When a sentence has a subordinate clause introduced by conjunctions like если, когда, потому что, хотя, etc., you almost always put a comma between the subordinate clause and the main clause.

So the comma here is required in standard written Russian.

Can we put the если-clause at the end? For example: Мышцы устают быстрее и осанка портится, если пропускать разминку.

Yes, that is also correct:

Мышцы устают быстрее и осанка портится, если пропускать разминку.

Meaning and grammar stay the same. The difference is mainly in focus and style:

Original: Если пропускать разминку, мышцы устают быстрее и осанка портится.
→ Starts with the condition, then gives the result. Very typical for rules and advice.
Reordered: Мышцы устают быстрее и осанка портится, если пропускать разминку.
→ Starts with the consequences, then explains under what condition they happen.

Both versions are fine and natural. The choice is mostly stylistic.

Is the sentence neutral in style? Would it sound okay in both spoken and written Russian?

Yes, the sentence is neutral and standard in style.

It’s perfectly fine for:
- Spoken language (e.g. a coach talking, a friend giving advice)
- Written language (e.g. an article, textbook, health brochure)

It doesn’t sound slangy, overly formal, or archaic. It’s a good model sentence you can safely imitate in most contexts where you’re giving general health or exercise advice.