A nice meditation from Qigong Master Kwai Chee Low (in his words below):
This is a simple and easy meditation method to benefit those who have weak Kidneys or weak Kidney functions. It will also help those who are about to go for Kidney dialysis and hopefully delay it by strengthening kidney function and kidney health.
This method was initially taught several hundred years ago by a Qigong master to people whose Jing was diminished due to excessive sex.
The Mingmen is directly opposite the belly button and the Kidneys are on either side of the Mingmen.
Meditation on the Mingmen
i. Sit relaxed and comfortable in meditation mode. As in my earlier meditation methods, I would recommend the fingers to be in Apan mudra mode as it helps to descend the internal qi. However Apan mudra should not be used if the practitioner is within the 1st-8th month of pregnancy.
ii. Natural breathing. Do a few cycles of pore breathing and/or breathing along the Central Channel to activate the internal qi flow.
iii. Look inwards and place a light focus on your "internal" Mingmen.
iv. Slowly inhale and draw external qi into the nostrils and down to Mingmen. Allow the energy to be absorbed into Mingmen and thus into the Kidneys. If you can, pause several seconds to allow the absorption.
v. Slowly exhale and sink the energy from Mingmen down into the lower dantian and then down to Huiyin. This helps to fill the "2nd lower dantian".
Repeat this cycle as many times as you desire. Instead of counting, it's better to base on time, say for 10, 20 or 30 mins a session.
Before your normal closing, it's recommended to do several cycles of pore breathing followed by breathing up and down the Central Channel.
In the case of young males, they have been known to have sex several times a day.
And the West has the hype that the more sex, the more health.
This is so wrong and this is due to Western medicine works on symptoms and not the root cause.
Chinese medicine and the thousands year history of qigong recognise the existence of prenatal Jing or essence which is limited and we'll die when this is exhausted.
Every ejaculation of sperm causes a depletion of this essence which is stored in the Kidneys. In the olden days, in China the rich will have seven or more wives.
So it's common that they will have excessive sex and this method was taught to them.
It's simple, really. You sit in meditation mode. Place your mind intent and focus on the pores of your skin.
Slowly inhale and draw in external energy from all directions into the pores of your skin into the centre or Central Channel.
Then exhale slowly and send your internal energy from the Central Channel out through your pores in all directions.
Breathing along the central channel
Breathing along the Central Channel is simple... Inhale and bring the energy from Huiyin up the Central Channel to Baihui, then exhale and sink the energy back to Huiyin and repeat.
You hold the Apan mudra for the whole of the meditation session.
Apan mudra has where you hold your fingers such that the tip of the thumb touches the tip of the middle and fourth finger with the rest of the fingers stretched out. The palms face upwards (see pic below).