אני אף פעם לא אוכלת הרבה לפני ריצה, ובכלל אני מעדיפה לשתות רק מים.

Because אוכלת is the feminine singular present-tense form of לאכול (to eat).

• אני אוכל = I eat / I am eating if the speaker is male
• אני אוכלת = I eat / I am eating if the speaker is female

Hebrew present tense agrees with the gender and number of the subject, even with אני (I).

The same thing happens later in the sentence:

• אני מעדיפה = I prefer (female speaker)
• A male speaker would say אני מעדיף

In Hebrew, אף פעם לא is the normal way to say never.

Literally:

• אף פעם = ever / at any time
• לא = not

Together, they mean never.

This is a very common Hebrew pattern. English usually avoids this kind of double negative in standard grammar, but Hebrew uses it naturally.

Examples:

• אני אף פעם לא שותה קפה. = I never drink coffee.
• הוא אף פעם לא מגיע בזמן. = He never arrives on time.

So even though it may feel redundant to an English speaker, אף פעם לא is exactly what you want here.

No. That sounds wrong or very unnatural.

The usual order is:

• אני אף פעם לא אוכלת...

The negative expression אף פעם לא works as a unit. Put it before the verb, not split up in an English-like way.

It is in the present tense.

• אוכלת = eat / am eating
• מעדיפה = prefer

In Hebrew, the present tense often covers both:

• a habitual meaning: I eat
• a current meaning: I am eating

Here, because of אף פעם לא and the general statement, it clearly means a habit:

• I never eat a lot before a run
• In general, I prefer to drink only water

Here הרבה means a lot and functions adverbially with the verb אוכלת.

• אוכלת הרבה = eat a lot

It is not describing a noun here; it is describing the amount of eating.

Compare:

• אני אוכלת הרבה. = I eat a lot.
• יש הרבה מים. = There is a lot of water.

So הרבה is a very flexible word in Hebrew.

Because after לפני (before), Hebrew very often uses a noun or a full clause, not usually a bare infinitive in this kind of sentence.

So:

• לפני ריצה = before a run / before running

This is natural Hebrew.

Other possible ways to say something similar:

• לפני שאני רצה = before I run
• לפני האימון = before the workout

But לפני לרוץ would generally not be the normal choice here.

Both are possible, but they mean slightly different things.

• לפני ריצה = before running / before a run in a general sense
• לפני הריצה = before the run or before the running session — more specific, referring to a particular run

In your sentence, the speaker is talking about a general habit, so לפני ריצה fits very well.

ובכלל can mean things like:

• and in general
• anyway
• as a general rule
• besides

Here it introduces a broader statement:

• ובכלל אני מעדיפה לשתות רק מים.
• And in general, I prefer to drink only water.

So the speaker first says something specific about eating before running, and then widens the point: more generally, she prefers only water.

Hebrew uses the infinitive after verbs like prefer, want, like, can, etc.

• לשתות = to drink

The ל־ at the beginning is part of the infinitive form and often corresponds to English to.

So:

• אני מעדיפה לשתות = I prefer to drink

More examples:

• אני רוצה לאכול. = I want to eat.
• היא אוהבת לקרוא. = She likes to read.

Because מים here is an indefinite/general object: water in general, not some specific water.

In Hebrew, the direct object marker את is used only before a definite direct object, usually one with ה־ or something otherwise specific.

So:

• אני שותה מים. = I drink water.
• אני שותה רק מים. = I drink only water.

But:

• אני שותה את המים. = I am drinking the water (specific water)

Since the sentence means water in general, there is no את.

Because רק usually comes right before the thing it focuses.

• לשתות רק מים = to drink only water

Here, רק focuses on מים, meaning that water is the only thing she drinks in that context.

Compare:

• אני רק שותה מים. = could suggest I’m only drinking water / all I’m doing is drinking water
• אני שותה רק מים. = I drink only water

So placement changes the emphasis.

It could, but it would mean something slightly different in emphasis.

• אני מעדיפה לשתות רק מים = I prefer to drink only water
  • focus on only water
• אני מעדיפה רק לשתות מים = I prefer only to drink water
  • this sounds more like the limitation is on the action or choice structure, and is less natural for the intended meaning

So in your sentence, לשתות רק מים is the better and more natural wording.

Hebrew often repeats the subject for clarity or emphasis, especially when a second clause begins.

So:

• ..., ובכלל אני מעדיפה...

This sounds natural and clear.

You could sometimes omit the second אני if context makes it obvious, but repeating it is very common and often stylistically smoother.

The word order is very natural Hebrew:

• אני אף פעם לא אוכלת הרבה לפני ריצה
• ובכלל אני מעדיפה לשתות רק מים

A few useful things to notice:

1. Negation comes before the verb:

   • אף פעם לא אוכלת

2. הרבה comes after the verb:

   • אוכלת הרבה

3. רק comes before what it limits:

   • רק מים

So even if the English translation feels straightforward, the Hebrew word order reflects normal Hebrew grammar and emphasis patterns.

No major changes beyond the feminine verb forms.

A male speaker would say:

• אני אף פעם לא אוכל הרבה לפני ריצה, ובכלל אני מעדיף לשתות רק מים.

Changes:

• אוכלת → אוכל
• מעדיפה → מעדיף

The rest of the sentence stays the same.

מים is grammatically a plural-looking form, but it functions as the normal word for water.

Like English water, it refers to an uncountable substance, but in Hebrew its form is historically plural.

You do not need to worry too much about that in this sentence; just learn מים as the standard word for water.

Example:

• המים קרים. = The water is cold.

Notice that Hebrew often treats it with plural agreement in some contexts. But for learners, the important thing is simply recognizing מים = water.