Before starting with force planning it is necessary to be clear about the basic concepts that define the orientation of strength training at present.


We must forget about old and outdated classifications that distinguished between maximum, submaximal and explosive force under the load criterion used. Where the maximum force was understood as the ability to lift a maximum weight (referring to 1 RM, I leave HERE a reminder), submaximum loads similar to 80-90% and explosive loads much lower, around 40-50%.


The first step in understanding this current definition of force is to review some basic concepts. For example, from the point of view of mechanics, force is any cause capable of modifying the state of rest or movement of another body. While for physiology, it is understood as the ability to produce tension that the muscle has when activated.

The first focuses on the external effect while the second, in the internal, from the same muscle contraction. Both definitions are not exclusive, they simply represent an approach, a different perspective, before the same phenomenon.


From what we have just seen, there are two sources of forces in relation: internal and external forces. As a result of this interaction, a third concept arises: The applied force.

It is the result of the muscular action on external resistances, which in the case of training are variable: the corporal weight, some foreign implement and even the technique of a movement will affect this production of force.


What interests us in the sport context is therefore to improve the capacity to produce applied force, since the power that can be generated depends on it.


Here I present a well-known example of the variations of force applied in the squat exercise:

Pico máximo de fuerza sentadilla

Figure 1.1. Badillo, J. J. G., & Serna, J. R. (2002). Basics of strength training programming



In the Y axis we see the force data measured in Newtons and in the X axis, the time (ms) Analyzing this graph we see two very clear details:


  1. The application of force varies according to time.
  2. In the squat there is a maximum force peak (PMF), and consequently, as time passes, it begins to descend.


This relationship between force and time is vital in the sport context, where in most gestures the limiting factor is the time we have.

In future publications we will discover more and more of this F-T relationship.


Badillo, J. J. G., & Serna, J. R. (2002). Bases de la programación del entrenamiento de fuerza (Vol. 308). Inde.

Izquierdo, M., Häkkinen, K., Gonzalez-Badillo, J. J., Ibanez, J., & Gorostiaga, E. M. (2002). Effects of long-term training specificity on maximal strength and power of the upper and lower extremities in athletes from different sports. European journal of applied physiology, 87(3), 264-271.