JING
Bei Tang Lang:
There should be no (long-term) injury to any Martial Arts practicioner if they have been correctly instructed and practiced as so!
If Jing is expressed correctly as Mantis 108 described, like a whip, no injury will develop.
After a whip is cracked it does not come boomer - ranging back to you, but is freed of tension, allowing for an immediate second, third crack.
The movements that are part of the “fa” of the “Jing”, (as Mantis 108 explained on the previous page) will eliminate any threat of injury and allow ultimate power. For instance, If you do not pivot the foot at the same time as you snap the calve and turn the waist, it might result in a popped knee. By pivoting the foot, a natural movement will then occur allowing for proper and full rotation of the waist. There should be no pressure or pull on any part of the knee. If you do not “extend the shoulder” at the end of the pucnh, you would chance having your elbow joint stressed.
Most practicioners, Chinese or Western whom have bad knees, are a result of improper stance work and transition movements.
Five Swords;
Not all Chinese are small, many have large builds. Fa Jing is the equalizer. By possessing the ability to Fa Jing, you are packing a KO every time you stirke.
Practicing how to Fa Jing should begin by over emphasizing the drills described earlier. Make each move deliberate and obvious. As time passses, the movements will become shorter and quicker, but will not sacrifice any of the power.
A basic one person stationary drill could be punching side to side.
Stand in a horse stance / right hand out in front grabbing / lift the pelvic forward / simutaneously :snap the right calve; pivot the right foot to the left 45 degree; turning the waist to the front whereas your left foot toes, knee, and belly button are in a line/pull in left grab to your “Bow Jou” position and punch with right hand to the front side. You would then do same on other side. This is abasic that can help with all aspects. There are more of these types, difficult (maybe I am too lazy to type it all out) to describe on line, that work the whole action or just certain parts such as popping the calves.
The weak links.
Thanks Buby. 
I try.
First off, I am so glad that the questions that pop up so far are really related to CMA. Then, a story. We practice the whipchain a lot. There was one point the manufacturer of the weapon used some cheap metal for the links. Needless to said they don’t hold and the chain can’t be used. So we have to reinforce the links. This is much the same in the case of Fa Jing. Frankly, the inability to explain Fa jing forces a lot of people resolved to adapte Kung Fu Mysticism. Hopefully a bunch of jagons and the questions would be like water over duck’s back. Personally, I believe in details and that’s all it is. The weak links in Fa Jing are the understanding and applying balance, vertical vecter, and space-time continuum. All these are but Kung Fu 101, but not a lot of people pay much attention to them, and they wonder why KF suck? It isn’t KF that suck but their foundations suck so their buildings are lucky to be standing up at best. How could good Kung Fu evolve from a poor (next to nothing) foundation? So again work on the basics.
Balance is perhaps the most boring, yet the best and easiest to correct and improve. Many people chose to skip this and those are the ones who complain KF sucks. Without a good understanding of this, the talk about weight (mass as energy) transfer is futile. If you are not aware of where your weight resides, you are not going to be able to transfer it peroid! So you must be aware of this. An excellent drill is the San Ti Sik of Xing Yi. From the Taiji to the liang Yi and to San Ti, that’s is IMHO one of the the best drills to understand balance. It is no wonder GM Sun Luk Tong regard it the most important if not the essence of Xing Yi.
Vertical vector bascially is the body structure aligned and on the move (mobilized balance) piror to the impact. Most people thought of striking as an horizontal vector and disregard the vertical that’s where the problem is - missing details again. It should be perceived as an dynamic event more so than just a concept or an object being observed. I like to call this the dynamic centerline. It is like the bow that’s fully draw. Not linear but curved. Most people understand this, if not , please refer to Pong Lai’s and my previous posts. Pong Lai again pointed another very important yet mostly left out detail in his last post. That is the toes! I rather refer it to as the balls of the feet but the toes are important in this as well. As the moment of truth, the impact moment, the toes grabs the ground like grabbing the nine hells (to borrow the old texts, lol…) You might wonder why is this important. Here the sweet part. As you grab the floor, you (the body) automatically pops the body weight to the balls of the feet. In the old days, this is referred to as Diu Yung Chun (lifting the main acupoint in the middle of the feet.) This is natural because your body is designed that way. It is not a secret but a detail. Then the dung tui as Pong Lai pointed out kicks in. The calves are major stablizers to maintain this dynamic. They are all related. Plain and simple. No Chi talk here because there is no need for it. further up would be the waist which is the continuum of the bow - the dynamic centerline. I will discuss this in the space-time continuum next.
This is more or less addressing what Five Swords is looking for. There are more than just the Whip type of Jing otherwise how would we be able to explain MA such as Muay Thai? Surely, no one would doubt they have Jing if they have encountered them. They too use a lot of the “waist”. Note that waist is actually hips joints and the waist muscles. This is where most KF misuse of the term waist. It is not just muscles, which is what the problem of localizing begins and the globel coherence fails. The dynamic centerline is muscloskeletal. In Taiji the open and closing of the Kwa is key to silk reeling jing. That’s basically saying we must pay attention to the muscloskeletal continuum not just the waist muscle (that could turn out to be Lik- strenght). Even a very slight opening and closing (cast and reel motion) of the hip joints, which of course can not be achieved without the waist muscles (the abs and the ducts), can do a lot of damage. Try doing sun punch from the standard Wing Chun position with the dynamic centerline contiuum (with all the details) that is explained (don’t try it on the plastered walls, your landlord won’t appreciate this as much as you would. lol…). Remember don’t push a strike; it won’t work! When you achieve the feeling that you are literally “hammering” (re: iron fist like a hammer) the wall or whatever object from that position, you have understood the vertical vecter very well. You can then apply the same contiuum and feeling to your strikes. I was going to explain the space-time continuum further with the Thai machnics but I am kind of tired of typing right now. So I will do it in the next post. Sorry. Hope you enjoy this one.
Mantis108
Part Deux
Space-time continuum here means the awareness of applying energy through the dynamic centerline. Without the awareness one is but moving and not being martial with the arts. This awareness in also very important in Mantis. Unlike other MA systems there are a lot of moves in Mantis that requires continuous strikes on single point base support or even aerial. These types of strikes can not be satisfied by just the silk reeling jing along. I find the best illustration is the flying knee (double one) of Muay Thai. This is not to say we can’t use examlpes in Mantis. In fact, there is a flying knee in TJPM Kung Lik Kuen but I thought I would use a more commonly know illustration. I am also sure that most people are familiar with the double flying kick which is more or less the same as the knee except it is longer range. The first knee (while having a base) is not a problem in utilizing the Silk reeling jing. But to do the second knee, which is aerial, we must do our best to understand the Space-time continuum. The second strike (of the other knee) must capitalize on the first strike’s recoil which means the recoil is the new dynamic centerline and so on so forth. It is the awareness (to the details) that keep the ever changing dynamic centerline alive. Recoil is actually a poor word to use because it gives the impression of drawing (telegraphing). However it isn’t about drawing and this must be studied well. In such a case, as in many others, the hip waist muscloskeletal continuum is most significant. It (the hip) pivots back and forth and side to side but again not localized or discounted from the core (spine-back). Also proper breathing technique helps here (Chi talks here. lol…) 
This is also the main reason why in CMA good posture is stressed otherwise the slacks will degenerate the posture and will cause the lost of jing.
A side note - the way Chen style Taijiquan’s solo Fa Jing is safe to uses and should not cause any damage to joints. An experienced MAist can reproduce the same fa jing feeling that is acquired through the practice with a partner or object in their solo forms. It is not the same case vice versa.
Mantis108
Thank you Mantis 108!
Thank you Mantis 108 for taking the time to explain things in such detail. I must confess that for a while I had considered many of the traditional arts and many of their training methods impractical and outdated. Thanks to knowledgeable practitioners like yourself and especially Pong Lai my viewpoints have sinced changed and I definitely have a greater appreciation for the traditional methods. Thanks again!
Hi Five Swords
Hi Five Swords,
Your are most welcome. Thanks for the compliments blush
Glad that you enjoy them. I hear you about losing faith on Kung Fu. Good Kung Fu are out there just that it’s harder to find. I am glad that Pong Lai has helped you reconsider the wisdom behind the old stuff. 
Regards
Mantis108