According to Newton's third law, for every action force there is an equal (in size) and opposite (in direction) reaction force. Force always come in pairs - known as "action-reaction force pairs." Identifying and describing action-reaction force pairs is a simple matter of identifying the two interacting objects and making two statements describing who is pushing on whom and in what direction. For example, consider the interaction between a baseball bat and a baseball. The baseball forces into the bat when it makes contact in an opposing direction; equally the bat forces the ball into the opposite direction. Together, these two forces exerted upon two different objects form the action-reaction force pair. Note that in the description of the two forces, the nouns in the sentence describing the forces simply switch places.
Comparing this scenario to Jiu-Jitsu, think about the bigger, stronger more athletic opponent forcing direction against a smaller, weaker individual. Just like the baseball in the previous example, the stronger force (bat) will overtake (deflect) the opposing (ball) weaker force. In Jiu-Jitsu a practitioner that uses brute strength consistently is utilizing "Action" in a linear aspect. This is why sometimes white belts are called "spastic" - every move a white belt makes has opposing force behind it. White Belts do not know how to apply technique and this is understandable. There are many blue belts as well and even higher belts that I have seen do not know how to apply technique so they use strength behind most of their moves. Jiu-Jitsu practitioners have coined this as "muscling through or out of a position/submission". Rather than using strength and muscling out or into every position; what would be a better method of using Action vs Reaction to your advantage?
It's like this; think about the next simplest geometric shape besides a line... the circle. A circle works in a spiral motion which in turn works as a torque or a counter force to a linear force. Think about a right cross or hay-maker being deflected by a parry and slip. A parry (spiral motion) would be slightly moving the linear (right cross) off target so that the right cross does not impact the opponent and in turn results in the attacker over-committing. This opens up attack points for the opponent while the attacker is retracting or recovering. This is why they say in Boxing or any type of striking martial art; "all it takes is one shot"...
Now let's apply this to Jiu-Jitsu. Think about what type of movements involve a linear motion? Let's start with the most basic and important aspect of this Martial Art - GRIPS. When an attacker is applying grips in an aggressive manner, he/she will often over-commit. This leads to counters that are technical in nature by way of hip movement and the application of the grips by the opponent. The movement of the hips and the grip application is spiral for example in an arm drag - 1. The torque at the elbow and wrist as it takes advantage of the over-commitment by the attacker 2. the hip movement in a half circle (angle) to allow the force of the attacker to keep going 3. the completion of the circular movement of the opponent as he/she attacks the back. This is just one of the many examples in respect to action vs reaction as it applies to technique.
Let's look at another example as it applies to Jiu-Jitsu. Many YouTube videos commonly display the action when there is no reaction? For example I am watching a video on a blackbelt teaching an Americana (upper key-lock) from mount. He is explaining in detail the hand position from top as it applies to locking down the position. The only problem is that in live grappling their is a "REACTION". The opponent is just laying down in a still position like a grappling dummy allowing for the attacker to apply the position, lock it down and submit. Unfortunately, it is not that easy. And this is the reason why very well known Professors (just to name a few) like Master Renzo Gracie, Rickson Gracie, Pedro Sauer, Tom DeBlass and my Professor Joao Zeferino prefer that their students (especially white belts) do not ONLY look to YouTube for technique or submissions. Why?......................................
Let's break down this video even further... If the opponent were fighting back, he or she would not allow for the attacker to apply the Americana so easily. If the opponent would have good technique, he/she would be turning sideways on their hip and implementing an elbow escape or bumping to sweep etal (we can talk about defenses/counters to this one all day) The point is that in order for the attacker in mount position to apply this submission, he/she would have to apply an action to cause a reaction in which the opponent over commits... So what are we talking about here? An action can be linear and over-commit or an action can SEEM LINEAR as IF it is over-committing (tricking the opponent)... But in actuality it is more diverse (circular) than that... the first action would be circular or spiral because it is a point of attack that will deflect the opponents defense in order to apply the counter IN A LINEAR FASHION. So in physics it would look like this --> circular action (attacker) causes a linear reaction (opponent) which is deflected to apply a counter linear action (attacker). In the example of the Americana from full mount, what would the attacker do to cause the opponent to over-commit a linear reaction? one way would be by applying a (non-committed) choke which forces the opponent to defend but allows the attacker to move freely in a circular motion to deflect the defense of the bottom opponent, by then driving the arm into the lock down position to execute the Americana.
This would be a better display or instructional video of one way to apply the Americana. I am sure there are other methods of circular movement that can be used to force an opponent to over-commit in a linear way so that your attack would move freely towards its intended TARGET(S) - because in Jiu-Jitsu there is more than one target available to you. Now this can work in either direction and it is akin to a game of Chess. Very good instructors will explain this as faking a move. However, to a white belt, there is no faking a move because he/she knows very few moves to begin with. And this is the same for many higher belt practitioners that are used to using strength and speed rather than technique. Nonetheless, knowing when to commit and over-commit is dependent on your technique and feeling of force also known as counter-balance. I have an article I wrote about counter-balance in my blogs https://www.brazilianjiujitsuacademyofqueens.com/single-post/2017/10/11/The-Science-of-Jiu-Jitsu
Hope you enjoy it! Oss!
Here is an PDF explaining linear vs circular as it applies to physics:
Another good article explaining linear vs circular as it applies to body movement: