Power striking in Wing Chun kung fu

Power generation in Wing Chun is very simple and can be explained using western scientific principles. Before I go any further, I apologise to those readers who disliked physics at school but a little mechanics is necessary for the explanation.  

When two objects collide, whether it is a fist hitting a jaw or two cars crashing, it is the transfer of energy that dictates how much damage is done. The transfer of energy can be further broken down into how much energy is being transferred and the ability of each party in the collision to take on board that energy. 

The amount of energy transferred in a collision can be calculated using the equation of 0.5 x mass x velocity x velocity to determine how much kinetic energy (moving energy) each party has before the collision and the same again for each party after the collision. Energy cannot be created or destroyed so if the amount of kinetic energy has changed then the energy must have been converted into another form. Normally in a collision this transformation of energy is expressed as heat, sound and mechanical destruction. In the case of a punch or strike hitting its target clearly we want as much as possible of the energy to be transformed into damage to the target. 

Step 1 of generating a powerful strike

The first step in generating power then is to ensure that as large a quantity of energy as possible is being created in the strike such that it is available to transfer to the target. Looking at the equation above we can see that there are two parts to generating this energy. The first one is mass. In order to maximise the amount of mass used in a strike, a Wing Chun practitioner strikes with the whole body mass moving either through stepping or turning. It is vitally important that as much as possible of the whole body mass is moving at the moment of impact otherwise only the fraction that is moving can be counted towards the energy transferred. The second factor is velocity (speed in a given direction) and if we look closely at the equation above we can see that velocity appears twice with the net result that if we double the speed we generate four times as much energy and if we triple the speed we generate nine times the energy for the same amount of mass. Velocity or speed is therefore of paramount importance and it is for this reason that Wing Chun strikes are delivered with the body as relaxed as possible. Rapid contraction of required muscles whilst simultaneously relaxing all others allows the strike to accelerate rapidly and reach maximum speed without being hampered by the strikers own body.

Step 2 of generating a powerful strike 

The second step in delivering a powerful strike is to be able to transfer the energy developed in the strike to the target in a manner that causes maximum damage. In order for maximum damage to occur it is important that as little as possible of the energy transmitted remains in the form of kinetic energy (moving energy) and as much as possible of the energy is transferred to the target. Several factors come into play at this point. The first one is structure. Correct structure aligns the bones of the striker such that the strike is angled upwards and there is a clear continuous path of force to the ground. This has two effects, it joins the striker to the ground effectively making their kinetic energy zero and also ensures that the target’s bodyweight / inertia acts to prevent them from moving and hence from attaining any kinetic energy The second factor is targeting the centre of the opponent (their Jic Seen) to prevent any energy being converted into movement either by pushing backwards or by causing their body to rotate. Thirdly it is important to switch off the strike once impact has been achieved to avoid applying force that can help the target to overcome its inertia and begin to move and to ensure that the strike ceases to move and hence has zero kinetic energy. At the same time it is important not to pull back or snatch the strike but rather to allow the target to bring the strike to a halt. Finally it is important to strike with an appropriate surface. If both parties are at or close to rest after the collision, the energy has to go somewhere and it will find release through breaking of bonds between cellular structures causing damage to the body parts involved in the collision. Energy always finds the path of least resistance but is indiscriminate and thus if the striking area is “harder” than the area being struck it will cause damage to the target, if the area struck is “harder” than the weapon then the it is the weapon that will take the bulk of the damage whilst if they are of equal “hardness” the damage will be evenly spread. It is therefore vital that the correct striking area is used and that the practitioner conditions their striking surfaces through the regular use of a wall bag or similar equipment.