This isn’t all that hard to believe if you do a bit of research. Humans normally use from 6% to 8% of the fibers in any given muscle at one time. The rest are recovering, clearing out waste products, repairing damage, etc.
It IS possible to use all or nearly all of the fibers in the muscle at once, effectively increasing the power by a factor of 15 to 20 times. While it can be done, and will occasionally happen spontaneously under stress, such as seeing your child in great & immediate danger, it has several caveats that are critical to understand.
The first and foremost is that it Hurts! This is Not the way muscles are designed to work and your body has a Strong interest in objecting, primarily because you can do yourself Severe damage. This is the same great strength enabled by PCP where 90 pound teenage girls hurl ten-plus large burly cops across rooms. It can rip the muscles from your bones or break those bones. PCP is a Very potent pain reliever and allows the user to ignore the pain that would otherwise keep them from doing such things. It also toasts their judgement so they are Likely to try it.
The next limitation is that muscles do not have a direct mechanism keeping them from working themselves to Death or destruction. Your nervous system provides that function by backing off the signal to the muscles after a few seconds and increasing the sensation of pain as you damage them and tear the fibers apart.
The ~burn~ felt when over-exerting yourself is the Nerve fatigue, not actual muscle response. Therefore, you can kill off or destroy substantial parts of your musculature by abusing it this way if you are not Very careful.
Keeping the use to well under ten seconds, and less than one if at all possible, is a good start. If you expect to use this in your life, get Training! Karate is probably the best as it and similar forms use the arms in ways that will allow you to learn it safely when taught by a particularly good sensei. Tai Kwon Do is not a good way to go as it emphasises leg work for unhorsing opponents; not too useful in this day and age and totally unsuited to learning careful use of power.
On the other hand, if applied Carefully, in a specific, brief and practiced way, you can produce results that Seem superhuman. This is one of the major ways that higher level martial artists can do many of the special techniques. They use the Full power of a particular muscle or set of them for a fraction of a second to add power to a move. Done by a trained practitioner, they will only feel a relatively small amount of pain. Toughening exercises are performed for this very reason; to get used to the pain involved. The ‘Ki-ai’ sound often heard is another method to mitigate the pain, and allow the user to focus on a result. Bruce Lee’s book on his methods may be of some help as well.
As an amateur in the martial arts, I have used this technique mostly in fixing cars, of all odd things. On several occasions, a stuck bolt or part was in my way. In one case, I sheared off a three-quarter inch hardened steel bolt because the alternatives were much worse. And I did it with a ten-inch wrench and no handle extensions because I was in a hurry and had nothing else available. This shocked the person working with me because he quite reasonably thought that wasn’t possible. And it wasn’t, within the limits we Normally work under. I set my arms and the wrench in position with the full normal strength of my body, then pulsed the muscles of my arms, shoulders and torso to 100% for a fraction of a second and the bolt sheared. And yes, it hurt, as it should. If it hadn’t I would have been seriously concerned for my health.
Contributions to the fight against ignorance are never wasted, albeit the struggle is eternal,
---- garnet_gargler