What Chinese Erotic Literature says about Semen Retention

The Golden Lotus - a Chinese Erotic Literature, like the Indian Kamasutra - talks about semen retention. It says:

If a you have sex but don't ejaculate...	...then...
Once	Your eyes & ears will be clear
Twice	Your voice will be clear
Thrice	Your skin will glow
4 times	You'll have no pains in your back or sides
5 times	Your buttock muscles and thigs will become strong & muscular
6 times	Your energy channels will flow freely
7 times	You won't die prematurely
8 times	You'll enjoy longevity
9 times	You'll achieve spiritual clarity

WARNING: I don't recommend having sex or any sexual activity and not ejaculating or orgasming. Consult a doctor regarding sexual health or general health problems. I'm just sharing interesting stuff that I have learnt with the world. I'm NOT taking responsibility for anything.

Source: The Golden Lotus: The Erotic Eessnce of China, Edited by Bret Norton