The ZHENKAI (zk) is the SI unit for badminton skill.

Heres the hierarchy -

Jordans skill is double of Zhenkai, so he's 2 zk.

Yao Cheng's skill is double of Jordan, so he's 4 zk.

My skill is double of Yao Cheng, so I'm 8 zk.

Zi Xin's skill is double of mine, so he's 16 zk.

Glennson's skill is double of Zi Xin, so he's 32 zk.

A junior national team guy's skill is double of Glennson, so he would be 64 zk.

A senior national team guy's skill is double of a junior, so he would be 128 zk.

The top badminton player in Singapore, like Ronald Susilo, would be double of a senior national team guy, so he would be 256 zk.

The number one in the world, Lin Dan, would even be FOUR times of Ronald Susilo, thus he would be 1024 zk.

What exactly does it mean when a person is, say, 100 zk?

It means that out of 100 matches, the guy will win 100 times before Zhenkai wins once.

So, since Zhenkai = 1 zk, if makes sense because if he were to play with himself, assuming all other factors are constant, the other Zhenkai will win one time before Zhenkai wins once, making it a draw, thus proving that this is true.

This has been invented by me, Yao cheng and Jordan.

Ha.