The Difference Between External Strength & Internal Power

For as long as I can remember, I have always believed that the body is meant to be used as a fully actualized, integrated unit – nothing can (or should!) exist in isolation.  By this I mean that muscle, tendon, ligament, and bone are all equally important and must all be unified in producing amazing degrees of strength and skill for fitness, martial arts, sports, or life. And, in most cases this is completely true.

However, in my mind it also meant that even though the most widely acclaimed adepts of internal power (IP) almost all say that strength training (weight lifting) and muscle building will have deleterious effects on producing internal power, I did not quite believe it to be true. Moreover, while I have been training in both external strength and internal power together for the past 4 years I was never quite able to articulate to myself the differences inherent in each model that allow them to produce vast amounts of force. I just trained both along with some very specific and strategic methods of recovery that I used to remove residual tension from the muscles to aid in my IP pursuit.


It was during my training with Dan Harden here in NJ this past weekend that it finally clicked and I got the difference in force production models through my thick skull.  Now, mind you, Dan has been saying the same thing since I first began training with him in 2009, it’s only now that I finally have the experience enough to hear it and make the distinctions – hey, we’re all constantly learning, I’m no different! J  (So, as usual please bear in mind everything you read here is my opinion and all mistakes are solely my own.)

Both models of external strength and internal power produce force.  It’s in the how that the differences lie.


“Get your facts first, and then you can distort them as much as you please.”- Mark Twain


External Strength

External strength method: force = tension.  The more tension brought to bear by the muscles, the more strength that is produced.  Learn how to contract your muscles harder and you will generate more force, i.e. – get stronger. This is a neurological phenomenon of increasing the percentage of muscle fibers recruited for a given task.

Internal Power

Internal Power method: force = MA (mass x acceleration). Yes, we all remember this equation from physics, but what does it mean in this context and how is it applicable to internal power? I’m going to oversimplify this because it would take up way too much text to spell out what can be demonstrated and explained in about 5 minutes in person.  Essentially, IP is about tissue movement.  The exercises and drills connect the body through the fascial meridians (see the book Anatomy Trains) and strengthen, thicken, and condition connective tissue in the body.  This mass of connected tissue is accelerated through sophisticated movement patterns, like spirals and dantien rotation, in a small space to produce massive amounts of force.  The more tissue that can be recruited, the more mass that goes into the equation.  The faster it can be accelerated through looseness which causes the tissue to snap, not tension, the more force that is produced, thus creating substantial internal power.

Now that we have a basic understanding of the differences between both models of force production the question becomes, for those pursing internal power that are not quite ready to give up strength training, is there a method that allows us to train them both concurrently?  Perhaps.  But that, my friends, is the subject of another article.


Jon Haas is a certified Underground Strength Coach and has been involved in the martial arts for over 30 years. He has been training in the Budō Taijutsu arts of the Bujinkan for more than 22 years and is currently ranked as a Kudan (9th degree black belt) under Jack Hoban Shidōshi.
Jon is the Head Strength & Conditioning Coach for VX Global and is a certified VX Sport Coach.

He is the owner and founder of Warrior Fitness Training Systems and author of the book, Warrior Fitness: Conditioning for Martial Arts.

Jon Haas is also a certified conflict resolutions specialist through Resolution Group International (RGI)

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  1. “Old school training for the modern world”.I like that phrase,Jon.Have you ever covered training methods that help to develop hand and eye coordination?This is so vital in every aspect of athletic endeavors.For myself,I utilize,knife-throwing,archery,rifle,pistol,slingshot,crossbows and the use of blow guns for that portion of my warrior training.Oh yeah….tameshigiri,too.Good stuff,pal.Keep it coming.Take care!

  2. But athletes who utilize external movement train to put more effective mass into their movements, do they not?

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