El avituallamiento ayuda a hidratarnos y recuperarnos.

In Spain, avituallamiento usually refers to supplies or provisions, and in a sports context it often means a refreshment point / feeding station / aid station during a race.

So in this sentence, it could refer to:

• the food and drink provided, or
• the refreshment station itself

In Spain, this word is especially common in running, cycling, hiking, and similar contexts.

Because avituallamiento is a masculine noun.

A useful pattern: many nouns ending in -miento are masculine:

• el avituallamiento
• el movimiento
• el conocimiento

So the article has to be el.

In Spanish, nouns used as the subject of a sentence usually need an article much more often than in English.

So El avituallamiento ayuda... sounds natural, while Avituallamiento ayuda... sounds incomplete or unnatural in most normal contexts.

Here el can mean something like:

• the refreshment station
• the provisioning
• the supplies

depending on the situation.

Because ayudar is commonly followed by a + infinitive when it means to help to do something.

So:

• ayuda a hidratarnos
• ayuda a recuperarnos

This is a very common structure in Spanish:

• me ayuda a estudiar
• nos ayuda a descansar
• te ayuda a mejorar

For an English speaker, it helps to think of it as help to..., even though in English we often just say help do... without to.

Because both infinitives depend on the same verb ayuda.

So a is shared by both:

• ayuda a hidratarnos y recuperarnos

This is the same idea as:

• aprendió a leer y escribir
• vino a comer y descansar

You could repeat the a, but normally you do not need to:

• ayuda a hidratarnos y a recuperarnos

That is grammatical, but less economical. The version with one a is the most natural here.

Because in Spanish, object/reflexive pronouns can be attached to an infinitive.

So:

• hidratar + nos = hidratarnos
• recuperar + nos = recuperarnos

This is called attaching the pronoun to the end of the infinitive.

You will often see this after another conjugated verb:

• quiero levantarme
• vamos a sentarnos
• puede ayudarnos

It is completely normal Spanish.

Nos means us or ourselves, depending on how the verb works.

Here it refers to a group that includes the speaker:

• hidratarnos = to hydrate ourselves / to get hydrated
• recuperarnos = to recover / to recover ourselves

So the sentence is talking about helping us rehydrate and recover.

Because in this sentence the idea is that we are the ones becoming hydrated and recovering.

These verbs are being used in a pronominal/reflexive way:

• hidratarse = to hydrate oneself / to become hydrated
• recuperarse = to recover

Without the pronoun, the verbs often sound more transitive, meaning they act on something else:

• hidratar a alguien = to hydrate someone
• recuperar algo = to recover something

So:

• hidratar = hydrate something/someone
• hidratarse = hydrate oneself / get hydrated

And:

• recuperar = recover something
• recuperarse = recover, get better

Yes. That is also correct and very natural.

Adding nos before ayuda makes the idea of helps us more explicit:

• El avituallamiento nos ayuda a hidratarnos y recuperarnos

The original sentence is still fine because the idea of us already appears in hidratarnos and recuperarnos.

Very roughly:

• ayuda a hidratarnos y recuperarnos = helps with our getting hydrated and recovering
• nos ayuda a hidratarnos y recuperarnos = helps us get hydrated and recover

Both work.

It is common in certain contexts, especially in Spain, but not in all everyday conversation.

You are especially likely to hear it in:

• races
• cycling events
• hiking
• logistics
• military or supply contexts

In casual everyday Spanish, depending on context, people might also use more familiar words like:

• comida y bebida
• suministros
• punto de avituallamiento
• avituallamiento líquido y sólido

So the word is normal, but somewhat context-specific.

A helpful approximation is:

a-bi-twa-ya-MYEN-to

A few notes:

• the stress is on mien
• the v sounds like b in Spanish
• ll is usually pronounced like y in most of modern Spain, though some speakers still keep a different ll sound

So in much of Spain, avituallamiento sounds roughly like:

a-bi-twa-ya-MYEN-to

Not usually in natural English.

Even though Spanish uses the pronoun nos, English normally just says:

• recover
• get better
• bounce back

So recuperarnos here is best understood as:

• to recover
• to recover physically

That is why a natural English translation would normally be something like:

• The refreshments help us rehydrate and recover

rather than help us hydrate ourselves and recover ourselves.