The Stimulus, Scaling, “As Prescribed” – Definitions and Their Importance

By Coach T

When you walk through the doors at CFE there are many things to consider…did you eat accordingly before attending the class…did you sleep well the night before…are you under stress at work? While there is some guesswork involved in a WOD, the staff at CFE has structured its classes so that you properly warmup, complete the workout, then cool down or mobilize. But how did you know if you had a great workout? The answer…is always written on our whiteboard. You may have seen or heard coaches talk about how it is the most important part of the workout and it’s called the “intended stimulus” or “stimulus” for short.

The stimulus is loosely defined as the level of intensity athletes should reach in order to get the most benefit from the programmed workout. There are several different ways this stimulus can be measured with the most common method being time. Knowing the appropriate time domain for a workout is important because not only does it give the athlete a goal for the workout, but it also ensures that different energy systems (or metabolic pathways) are being utilized for different workouts. 

The CrossFit Level 1 Training Guide uses four different models of fitness to answer the question: ‘What is fitness?’ One of these models of fitness is the metabolic pathways, or energy systems that are used for all human action. CrossFit argues that total fitness requires training and competency in all three of these pathways and balancing the effects of these three pathways helps determine the how and why of the cardio that is practiced in many CrossFit gyms. However, it can become quite common for athletes to favor one or two of the pathways over the other[s], which is a common fault in CrossFit training. Therefore, it is important that athletes understand the differences between these three pathways, and which one is required for a specific workout. 

The first metabolic pathway is called the phosphagen pathway and it is responsible for the highest-powered activities, such as those that last less than ten seconds. Example activities in the phosphagen pathway are a 50-meter sprint or a 2-rep max deadlift. Each of these activities last only a matter of seconds but require a high level of power output.

The second metabolic pathway is called the glycolytic pathway and fuels moderate-powered activities, or those that last up to several minutes. For example, a 400-meter sprint or an elite level ‘Fran’ time would fall under this energy system.

Finally, the oxidative pathway dominates low-powered activities, such as a 1 mile run or workouts lasting 20 minutes or more (think partner WODs on Saturdays). It is not uncommon for several of the metabolic pathways or energy systems to appear in one workout.

One of the most important things to note…when the intent of the workout is lost, athletes often end up training the same energy system over and over again and they develop a deficiency in one or two of the other metabolic pathways. This results in a loss of fitness. 

“Scaling” or “the scaled athlete”

Want some good news? Maybe with the exception of a few, very gifted athletes, most people start their CrossFit journey as “scaled athletes”. The principle reason to scale is for the reasons stated above…to help the athlete achieve the intended stimulus. Some other reasons for scaling may include: injury, physical limitations, and the de-conditioned athlete. How coaches scale a workout for an individual can vary but generally it’s loading(the weight involved in a movement) or volume(the number of repetitions performed). Movement substitutions are generally reserved for the injured or those with physical limitations and not simply because someone “doesn’t feel like doing a movement”. 

“Rx” or “as prescribed”

As programmers, we are trained to create workouts with the gym’s elite athletes in mind. Often you will see very standard loading for “heavy” “moderate” or “light”. A “heavy” workout may encompass clean and jerks at 225 for the men. A “moderate” loading may look like 35lb dumbbells for the ladies. “Light” loading heavily depends on the movement and volume but the prescribed weights in the benchmark workout “Fran” are considered “light”. Most athletes have achieved a desirable level of fitness when they can complete most of their workouts Rx. In addition, this is the goal for the “scaled athlete” and is achieved through consistency and intensity.

At CFE we want athletes to have a better understanding of the stimulus, scaling and completing a workout Rx.

This will help athletes feel empowered with the knowledge they need moving forward towards their goals. This sense of empowerment will also create and sustain a level of trust between them and the coaching staff. 

Start here

Book a free intro today so we can learn all about you, your goals and how we can help you reach them
Free Intro