Небольшая заминка помогает расслабить мышцы, а потом можно зайти в сауну.

Yes, заминка can mean a delay, hold-up, or awkward pause in many contexts.

But in sports, fitness, or health contexts, заминка often means a cool-down: a short period of light movement after exercise.

So in this sentence, небольшая заминка means something like a short cool-down or a brief winding-down period, not a problem or delay.

Because заминка is a feminine singular noun.

In Russian, adjectives must agree with the noun in gender, number, and case:

• небольшой = masculine
• небольшая = feminine
• небольшое = neuter
• небольшие = plural

Since заминка is feminine singular and is the subject of the sentence, the adjective is also feminine singular nominative: небольшая.

Because it is the subject of the sentence:

• Небольшая заминка помогает...
• A short cool-down helps...

The thing doing the helping is заминка, so it appears in the nominative case.

The verb помогать / помочь often works with an infinitive, just like English help to do something.

So:

• помогает расслабить мышцы = helps relax the muscles

This structure is very common:

• помогает понять = helps (someone) understand
• помогает уснуть = helps (someone) fall asleep
• помогает восстановиться = helps (someone) recover

Russian does not need an extra word like to before the infinitive.

This is an aspect question.

• расслабить = perfective → to relax something fully / bring about the result
• расслаблять = imperfective → to be relaxing, to relax repeatedly, or in a general/process sense

After помогает, both aspects are possible in some contexts, but here расслабить sounds natural because the idea is achieving the result: the muscles become relaxed.

So помогает расслабить мышцы means:

• it helps get the muscles relaxed

If you said помогает расслаблять мышцы, that would sound more like:

• it helps with relaxing muscles in general
• it helps relax the muscles as an ongoing process

In this sentence, the perfective is the more natural choice.

Мышцы is the plural form of мышца (muscle).

Here it is the direct object of расслабить:

• расслабить что? → мышцы

Since мышцы refers to inanimate things, the accusative plural looks the same as the nominative plural:

• nominative plural: мышцы
• accusative plural: мышцы

So although it is grammatically the object, the form stays мышцы.

Both а потом and и потом can mean and then / and after that, but they are not exactly identical.

• и потом usually just adds the next action
• а потом often marks a transition or a new stage

In this sentence, а потом sounds natural because the speaker is moving from one phase to another:

1. first, do a short cool-down
2. then, go into the sauna

So а потом has a slight sense of and then after that / and only then.

Because можно often forms an impersonal construction in Russian.

• можно = it is possible, one can, you can

So:

• можно зайти в сауну = you can go into the sauna
• literally: it is possible to go into the sauna

Russian often leaves the subject unstated in sentences like this when the meaning is general.

Other examples:

• Можно войти? = May I come in?
• Здесь можно курить? = Is it allowed to smoke here?
• После тренировки можно отдохнуть. = After training, you can rest.

Because в сауну shows motion into the sauna.

With в:

• в + accusative = motion into
• в + prepositional = location in

So:

• зайти в сауну = go into the sauna
• быть в сауне = be in the sauna

This is a very important Russian pattern:

• идти в зал = go into the gym / go to the gym
• быть в зале = be in the gym/hall
• войти в комнату = enter the room
• находиться в комнате = be in the room

Зайти is a perfective verb that often means:

• to go in / enter
• to drop in / stop by
• sometimes to come by briefly

Here, with в сауну, it clearly means to go into the sauna or to step into the sauna.

It is a little more specific than a basic verb like идти. It suggests entering a place, often as a single completed action.

So:

• можно зайти в сауну = you can go into the sauna / step into the sauna

Yes, Russian word order is fairly flexible, but the original sentence sounds natural and neutral:

• Небольшая заминка помогает расслабить мышцы, а потом можно зайти в сауну.

This order presents the information clearly:

1. the cool-down helps relax the muscles
2. after that, going into the sauna is possible

You could rearrange parts for emphasis, but the original is a good standard version for learners.

For example, Потом можно зайти в сауну is also possible, but putting а потом after the comma makes the transition smoother in this sentence.

Yes, it sounds natural, especially in a wellness, sports, or recovery context.

The only thing to remember is that заминка is especially common in exercise language, where it means cool-down. So the sentence sounds like advice about what to do after training or physical activity:

• do a short cool-down
• then go into the sauna

That is a very natural Russian way to express this idea.