الرياضة كويسة للجسم.

A natural Egyptian pronunciation is:

er-riyāDa kwayyisa lil-gism

A few notes:

• الرياضة → er-riyāDa
  The الـ changes in pronunciation here because ر is a sun letter, so the l sound assimilates.
• كويسة → kwayyisa
  This is a very common Egyptian word meaning good.
• للجسم → lil-gism
  This is basically for the body.

You may also hear small pronunciation differences depending on the speaker.

In Arabic, sentences in the present tense often do not use a separate word for is / am / are.

So:

• الرياضة كويسة = Exercise is good
• literally: Exercise good

This is completely normal in both Egyptian Arabic and Standard Arabic for present-tense statements.

If you wanted a past meaning, then Arabic would normally use a verb, such as كانت for was in the appropriate context.

Because الرياضة is a feminine noun, the adjective has to agree with it.

• كويس = good (masculine)
• كويسة = good (feminine)

Since رياضة is feminine, you say:

• الرياضة كويسة

If the noun were masculine, you would use كويس instead.

It can mean either, depending on context.

In everyday Egyptian Arabic, رياضة often refers to:

• exercise
• working out
• sports in a general sense

So الرياضة كويسة للجسم could naturally be understood as:

• Exercise is good for the body
• Sports are good for the body

If you are talking about personal health, English speakers will often translate it most naturally as Exercise is good for the body.

Because ر is one of the sun letters.

With sun letters, the l in الـ is not pronounced clearly; instead, the following consonant is doubled.

So:

• ال + رياضة
• becomes pronounced roughly as
• er-riyāDa

This is a pronunciation rule. In writing, it still stays الرياضة.

By contrast, in الجسم, the ج is not a sun letter, so the l sound remains:

• el-gism

للجسم means for the body.

It is made from:

• لِـ / لـ = for / to
• الجسم = the body

So:

• ل + الجسم
• becomes للجسم

This kind of merging is very common in Arabic spelling and pronunciation.

Arabic often uses the definite article in places where English may or may not use it.

Here, الجسم means the body, but in English we often translate the whole phrase more naturally as:

• good for the body
• or simply good for your body / good for the body

So the Arabic is definite, and that is perfectly normal here.

It is mainly Egyptian Arabic because of كويسة.

In Modern Standard Arabic, you would be more likely to see something like:

• الرياضة جيدة للجسم

In Egyptian Arabic, كويس / كويسة is much more common in everyday speech.

So the sentence is very natural colloquial Egyptian.

Yes, but that sounds more like Modern Standard Arabic or more formal speech.

Compare:

• الرياضة كويسة للجسم → natural everyday Egyptian
• الرياضة جيدة للجسم → formal / Standard Arabic style

If your goal is to speak like people do in everyday Egypt, كويسة is the better choice.

In Egyptian Arabic, the letter ج is usually pronounced as g, not j.

So:

• جسم
• is pronounced gism

That is why الجسم sounds like:

• el-gism

This is one of the most noticeable features of Egyptian pronunciation.

You might hear reduced or casual phrasing in speech, but الرياضة كويسة للجسم is the most normal full sentence here.

Using الرياضة gives the general idea of exercise / sports as a concept.

If you remove الـ, the sentence can sound less natural in this generic statement. So for a learner, it is best to keep:

• الرياضة كويسة للجسم

The sentence follows a very common Arabic pattern:

• noun/topic + adjective/comment + prepositional phrase

So:

• الرياضة = exercise / sports
• كويسة = good
• للجسم = for the body

Putting it together:

• الرياضة كويسة للجسم
• Exercise is good for the body

This kind of structure is extremely common in simple present-tense Arabic sentences.

كويسة is the feminine singular form.

Here is the basic pattern:

• كويس = masculine singular
• كويسة = feminine singular
• كويسين = plural in many everyday contexts

So كويسة is specifically used when the noun it describes is feminine singular, as الرياضة is.