Why both "gymnosperm" and "gymnastics" have the same beginning?

During studying biology, we encountered two words in the botany part:

gymnosperm and angiosperm

While -sperm is not officially a suffix, we can still refer to the word 'sperm'. Sperm is from Greek sperma, meaning seeds. The prefix for sperm including sperm(o)-, spermat(o)- and spermi(o)-, which we just learned in the second part of Lesson 13.

The prefix angi(o)- is originated from Greek angeion, meaning vessel. Because the seeds of angiosperm are enclosed, hence its name. We learned angi(o)- in Lesson 8-1.

How about the prefix gymn(o)-? The prefix gymn(o)- is originated from Greek gymnos, meaning naked or pertaining to things that are naked.

Well, it makes sense for gymnosperm since their seeds are not enclosed. Gymnosperm meaning "naked seeds".

What about gymnastics is also using gymn(o)-? Is there anything related to naked in gymnastics?

gymnastics. Source: wiki

According to Jonathan Silvertown's "An Orchard Invisible: A Natural History of Seeds." and I quote from Wikipedia, "The word gymnastics derives from the common Greek adjective γυμνός (gymnos) meaning "naked", by way of the related verb γυμνάζω (gymnazo), whose meaning is to train naked", "train in gymnastic exercise", generally "to train, to exercise". The verb had this meaning, because athletes in ancient times exercised and competed without clothing."

So that's why gymnastics using the prefix 'gymn(o)-'.

However, it is only applied to Western worlds. In China, the martial arts performers do not practice naked.

Chinese martial arts. Source: Wiki