The StratFit Grading System: A Comprehensive System for Intensities, Reps, and Loads

The StratFit Grading System: A Comprehensive System for Intensities, Reps, and Loads

The StratFit Grading System: A Comprehensive System for Intensities, Reps, and Loads


Physical training is composed of two elemental variables: the intensity and amount of work.  

  • Intensity: The level of the work in relation to an athlete’s maximum for the exercise/event.  For lifting events, intensity is the percentage of the athlete’s one repetition maximum (weight)  For running, cycling, and swimming events, intensity is the percentage of the athlete's maximum speed.
  • Amount: The extent of the work.  For lifting events, the amount is equal to the number of repetitions.  The amount for running, cycling, and swimming events is equivalent to the distance.

These elements are combined in strategic ways to form the fundamental units of training-

  • Macrocycle: A large periodized training unit that typically contains preparation, competitive, and recovery periods.
  • Period: A group of mesocycles that have a particular objective.
  • Mesocycle: A multi-week unit consisting of multiple microcycles with a particular objective that always ends in a recovery “deload” microcycle.
  • Microcycle: A microcycle is a multi-day unit that contains multiple workouts.  A Microcycle always ends with a rest/off day.
  • Workout: A group of training activities with a particular objective.
  • Activity:  An activity is a training event (a certain spatial form: bench press, powerlifting squat, snatch, etc.) with a certain number of sets (of repetitions)
  • Action: A set of reps with a given spatial form

The skillful prescription of intensities and amounts in units to manifest certain training effects at certain times is the real art of strength & conditioning coaching.  The larger the training unit across which a coach applies foresight to prescribe and control these elements, the greater their craft.

With StratFit Digital, we are giving coaches very precise tools to empower them to use intensities, amounts, and units with peak creativity to develop masterful training strategies. With our applied science and digital technology system, coaches can skillfully combine the elemental and fundamental variables into the foundational value of physical training: The Internal Training Load.

The internal load is the level of adaptational stress a given training unit applies to the athlete.

Essentially, a coach prescribes certain intensities and reps in units of training to develop a certain load at particular times so an athlete’s form and preparedness progressively develop; this development leads to improved performance and success on the competitive field.  The process is the same, albeit less complex, for a personal trainer and a non-competitive gym client.

The process of prescribing and controlling loads starts when the coach contemplates the athlete’s goals and designs a training strategy to ensure the athlete achieves these aims. All of this can be intimidating for a rookie trainer, and even for a seasoned strength & conditioning coach, it's a lot to think about and keep track of.  

At StratFit our purpose is to create an applied science to put all the power of the world of theoretical training under a coach's control.  The whole point of applied science is to use mathematics, logic, and technology to create practical shorts cuts to make particular processes more efficient and effective.  When part of a process becomes more efficient it frees up the operator to focus attention elsewhere and results catapult to a higher level.


One fundamental way StratFit is employing logic to empower coaches is with our intuitive Grading system for describing intensity, reps, and loading “ranges.”

When a rookie trainer is learning how different intensities and amounts of reps affect an athlete, or even when a seasoned coach is contemplating the topography of loading across time, it is useful to start by thinking in qualitative terms before thinking of actual numerical quantities. 

Words are more intuitive to the human mind, so for beginners learning and veterans roughing in a strategy, so logically placing qualitative terms to training quantities is very valuable.  Most athletes will understand qualitative words better than numbers anyway, making communication between the coach and athlete more effective.

This idea is not new and I don’t claim to have created it, however, StratFit has expanded it into a completely integrated system for understanding the intensity, reps, and loading of training.

Intensity Grading

In the Science of Sports TrainingThomas Kurz provided a resistance grading scheme by Naglak.  This scheme described how “heavy” a weight will feel to a lifter according to how many reps the lifter could perform maximally with the weight.  Naglak’s scheme looks like this-

Using an AMRAP (As Many Reps As Possible) equation that returns the maximum reps with a given intensity we can attach actual intensity ranges to Naglak’s resistance zones.  The updated table is then this-

This scheme makes the concept of intensity (as a percentage of 1 repetition maximum) very intuitive.  If a coach prescribes a set in the range of 98-99%, the weight will feel Maximal to the lifter, with 92-97% it will feel Submaximal, 81-91% will feel Heavy, 68-80% will feel Moderately Heavy, 57-67% will feel Moderate, 49-56% will feel light, and less that 49% will feel very light.

This scheme is very informative when designing a strategy because it gives the coach a good idea of how stressful the weight will feel to the athlete regardless of the number of reps.  It simply informs the coach how the weight will immediately feel on the athlete’s body.  This is useful because when a lifter has accumulated significant fatigue across a number of days or even weeks it might not be wise for them to even touch a Maximal, Submaximal, or even Heavy weight.

Reps per Set Grading

Since this scheme is very useful, I thought we could expand the use of Naglak’s terms to describe the difficulty of completing a number of reps with a certain intensity.  In this way, we can grade any training set according to how difficult it will be to complete for the lifter

The AMRAP equation above provides us with the “Maximal” number of reps in a set for any intensity. 

“Moderately Heavy” is the median grade in the scheme so I deduced that this would be analogous to the number of reps that Prilepin’s chart labels “Optimal’ for a set.  The StratFit Abstract Internal Loading Equation returns the reps for every intensity (reverse engineering from a given intensity and an abstract load of 0.2 returns Prilepin’s optimal reps).

It is then simple to place two equidistant points between the “Maximal” and “Moderately Heavy” reps values and place the Submaximal and Heavy labels to these reps values.

It is logical to place a “Light” label on a rep quantity that is half of “Moderately Heavy” (Prilepin’s Optimal).  To determine the “Light” number of reps with any intensity we perform the same process as for the “Moderately Heavy” value, reverse engineering with the given intensity and an abstract load of 0.1 instead of 0.2.

It is then simple to find the rep quantity that is equidistant for the Light and Moderately Heavy numbers; this is the “Moderate” number of reps for this intensity.

We determine the “Very Light” reps buying by dividing (and rounding) the Light reps by 2.  The following table shows the grading for various numbers of reps with various intensities.

We combine the separate intensity and rep grades into a single table to get a very elucidative view of the difficulty of various training sets.

Loading Grades

The internal “Load” of a training unit is a qualitative and quantitative combination of the intensity and amount (reps) of the unit.  So far we have been looking at the quantities of a “set” or “action” level training unit.  Since we have logically defined grades for the intensity and rep quantities for a set we can then expand this to the Loading concept.

There are two interrelated ways to look at the Load.  We can look at it in the abstract (without taking into account the spatial form of the action, only looking to the intensity and reps) and the in as the actual internal load (taking into account the specific stress factor of the spatial form).  

The abstract loading value tells us what the movement-specific fatigue will be for an action (set).  The actual loading value tells us the level of stress the action places on the whole organism

If a coach is focusing on the effect of fatigue on movement technique and the level of delayed onset muscle soreness (DOMS) in the primary working muscles from the action-activity following the session the abstract load is the key value. 



The abstract internal load equation is-


Reps / (Prilepin Minuend - Intensity)

The actual internal load equation is-

Spatial Form Stress Factor * Abstract Internal Load

There is much more information on the site about these concepts.  Please see the links, and for a real deep-dive, check out the academic papers.

We can create focal point loading values for each grade with these concepts and the logic we developed to grade the intensity and reps. When a coach designs a training activity, day, and microcycle, StratFit Digital will determine which focal point value the unit's load is closest to and will automatically inform the coach of the loading grade.

Loads as a Percentage of Maximum

Logically a Maximum Load for a training week would be equivalent to that of the largest competitive Load in sport.  An Ultramarathon/100-Mile Run provides that value with a Load of 18.9.  Taking that has 100%, we can then look at all Loads as percentages. By determining the percentage focal points for grading for each training unit, we arrive at a fully intuitive approach to training programming.

These focal points are based on the work of the greats in training science and by using the StratFit Loading calculation system to determine loads of various competitive activities.  The actual loading values of various competitive activities are in the following table-

The loading values of the competitive activities and the way they correspond to loading grades forms a very intuitive conceptual system for designing training strategies.  Strength & conditioning coaches, Weightlifters, Powerlifters, Body Builders, and Cross Fitters all have strong mental conceptions of the stress from various competitive activities.  By attaching actual values and grades to these mental concepts, we create powerful measurement and prescription tools for training sets (actions), activities, sessions, days, and even microcycles.  

StratFit Digital provides these values and grades for you as you design a strategy.  You develop specific loads and place dates on them to bring about certain levels of development at critical moments in time. 

When we combine this with our system for determining the training potency of a training unit for the various physiological abilities it makes developing the combination of a certain level of adaptation and ability profile a precise process. 

With StratFit Digital our purpose is to empower coaches to turn their process of designing training strategies into a proper art.

I will publish more detailed information on these concepts soon, stay tuned and Achieve Beyond.

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