Durable tennis players with strings of monofilament, why?

Question

The Babolat advertising here mentions the durability with players such as Rafael Nadal. According to google, durability means "the ability to withstand wear, pressure, or damage". I am not sure what it means here: it does not certainly mean too muscular because muscle is very expensive cell in terms of natural metabolism rate aka energy needed per time unit. Too muscular person cannot continue playing because of getting tired during a long run so not durable.

Now I am trying to make the connection to durability and monofilament strings. What do the two things have to do with each other? I cannot see the connection. Please, explain:

Why should durable tennis players use strings of monofilament?

Answer 1

Monofilament (mono = one) strings are one single strand of string, extruded during the string manufacturing process as a single solid strand.

Multifilament (multi = many) strings are several (usually hundreds) of tiny filaments inside a coating or sheath - no single solid strand.

What the guy in that video is saying is that monofilament string made from polyester material is made for a single purpose: to be as durable of a string as possible. Players such as (like the guy says) Rafael Nadal use monofilament polyester strings because they last the longest when you hit with an extreme amount of spin and strength, as Nadal does. So the monofilament poly string lasts him longer than any other string would.

You can read up more about different string types (materials and construction) here.