Before discussing Power Principles, it is helpful to understand how speed and mass can amplify force. Consider the following example: Two asteroids of equal mass are approaching Earth, but one is traveling twice as fast as the other. According to the laws of physics, doubling the mass of an object doubles its kinetic energy, while doubling its speed quadruples its kinetic energy. The Power Principles leverage these same laws of physics—speed and mass—to generate greater striking force.

There are three primary Power Principles, along with a fourth, often referred to as the "hidden" Power Principle. To be effective, each principle must be applied with proper timing:

• Backup Mass Inertia (Depth)

• Torque Rotation (Width)

• Marriage of Gravity (Height)

• Borrowed Force

Backup Mass (Inertia)

Backup Mass occurs when the entire body moves in a straight line (depth) directly behind the strike. It is essentially the horizontal-plane equivalent of Marriage of Gravity. For example, a rear-driving elbow executed with full-body backward movement or a straight punch delivered while shuffling forward. Without the accompanying straight-line body movement, these strikes would still be effective but generate less force.

Torque (Rotation)

To create torque, the body must twist or rotate (width). Techniques that incorporate rotational motion produce significant force in a small space. Torque is evident in many movements, particularly those involving a cross-step into a twist stance. The unwinding of this stance generates torque, amplifying the power of the strike. Since almost every block and strike utilizes hip rotation, Torque is the most widely applied Power Principle.

Marriage of Gravity (Height)

Marriage of Gravity is best described by Ed Parker in the Glossary of Terminology from Infinite Insights Into Kenpo Karate, Volume 4:

"The uniting of mind, breath, and strength while simultaneously dropping your body weight along with the execution of your natural weapon(s). Timing all of these factors with the dropping of your body weight greatly adds to the force of your strike. This combined action literally causes a marriage with gravity."

Borrowed Force

Borrowed Force involves using an opponent’s momentum against them—either by moving with or against their force. One method is to step into an oncoming opponent, striking as they charge forward. Another approach is to remain stationary and strike as the opponent moves into range. Borrowed Force can also be applied by redirecting the opponents force instead of striking into it.
A good example of this in the opening move of the technique Redirected Lightning.

Application: Clashing Rage

Each technique in the Parker Kenpo system is based on one or more of these Power Principles. While multiple principles often work in conjunction, one typically serves as the dominant force behind a technique.

Let’s analyze the technique Clashing Rage and identify the Power Principles at play:

• Ideal Attack: The opponent charges from the front, attempting to tackle. The defender has enough time and distance to engage by moving forward.

• Step Forward & Initial Strike: The defender steps forward at a 10:30 angle into a Left Transitional Neutral Bow Stance, delivering a right knee to the opponent’s solar plexus and a right thrusting back knuckle to the opponent’s face. A left positional check is placed on the opponent’s head. Since both the opponent and defender are moving forward, this movement utilizes Backup Mass and Borrowed Force.

• Downward Elbow Strike: The defender plants back into a Left Transitional Neutral Bow Stance and delivers a right downward elbow to the opponent’s upper spine. Marriage of Gravity is applied through the downward motion and weight drop.

• Follow-up Elbow Strike & Face Grab: Pivoting into a Left Reverse Close Kneel Stance, the defender delivers a left inward overhead downward elbow to the opponent’s upper spine, continuing into a left-hand grab to the opponent’s face. Again, Marriage of Gravity enhances the power of the strike.

• Twist Stance & Head Manipulation: Stepping back into a Right Front Twist Stance, the defender uses a left-hand pull to turn the opponent’s head upward, creating a fulcrum. Torque is in effect due to the twisting stance and rotational force.

• Elbow Strike to Face: Pivoting into a Right Neutral Bow Stance, the defender delivers a right inward elbow to the opponent’s face. Marriage of Gravity plays a role in maximizing strike force.

• Groin Strike with Back Hammer Fist: Pivoting into a Right Reverse Bow Stance, the defender delivers a right back hammer fist to the opponent’s groin. Torque generates additional force through body rotation.

• Final Kick & Exit: A right rear lifting heel kick is delivered to the opponent’s groin, followed by a right front crossover and cover-out toward 6:00.

Based on this analysis, Marriage of Gravity appears three times in Clashing Rage, making it the overriding Power Principle in this technique.

~ The data presented herein was compiled by AIK Black Belt Clifford Johnson in February 2025.