Unit 1 – Workload Intro

What is fitness? Good question. Seems there is no definitive answer in the industry today. The word “fitness” gets tossed around regularly with no real comprehension as to what adaptation (physical change) is being discussed. 

In this section we will explain the expected physical adaptation we call the “fitness” of throwing. Bare with us as we explain how an arm adapts and develops “throwing fitness” through a well built throwing program.

To begin to understand the uniqueness of throwing and the adaptation the body experiences through the progression of a throwing program we need to first start by understanding physical adaptation in general activity as it is defined in research. 

Majority of research identifies general physical training by 3 categories…

Long slow distance training (LSD)

Sprint interval training (SIT) 30 sec maximal bouts 

High intensity interval training (HIIT) 1-4 mins all out 


In research it is important to understand the differences in each of these categories and how they are tested. 




Research around LSD training defines it as…


“Traditional LSD training entails an individual sustaining a submaximal workload for a long period of time, or successfully completing a fixed distance/time through a higher than average power output (Coyle 1995)”


In some cases you could argue throwing long toss or having a catch could be considered LSD training. The long duration of throwing and fixed time by definition mean you could consider this aspect of throwing fits this model. But is it the best model to explain the adaptation experienced by an athlete on a progressive overload throwing program?


SIT and HIIT- 


Research around SIT and HIIT training define the two as…


“HIIT and SIT require the individual to perform repeated bouts at close to maximal intensity for a short period of time with a reduced training volume (Laursen and Jenkins 2002; Gi- bala et al. 2006).“


You could argue these models could be assigned by label to things such as high intensity plyocare throwing or general max intensity bullpens. The short bout nature of these segments in the throwing day would lead to the adaptations described surrounding both the SIT and HIIT models. 


The average inning length in the MLB in the 2019 season was 20.56 minutes long. Split this in half for the half inning and we would argue athletes in a game are experiencing the intensity of pitching at 7-10 minutes long. This aspect of throwing lends itself to more closely resemble both SIT and HIIT models by research. 

Throwing programs as a whole do not fit any of these categories perfectly. In certain aspects though you could also make a case that throwing fits into each of these categories uniquely. 

Since throwing doesn't fit any of these general models we will go ahead and create a new one (“Throwing”). For the sake of simplicity we will say that the goal of any throwing program is to build “Throwing Fitness'' through the act of “Throwing”.

With that being said and our new category “throwing” having been defined, let's look the expected adaptations of “throwing”.



When load is greater than tissue tolerance we see injury occur. 

Let's make sure you caught that… When load is greater than tissue tolerance we see injury occur. 

Wait wait wait. No like really let that sink in. Tweet it. Go say it to yourself in the mirror. Let it sink in… When load is greater than tissue tolerance we see injury occur. 

Phew. Ok. Back to our regularly scheduled program…

When load is greater than tissue tolerance we see injury occur. This means we need to prepare the athlete to handle the load the athlete will experience in competition. 

To begin to build a throwing program appropriately we HAVE to first understand the in-season demand of the athlete. Our goal is to progressively build adaptation over time to reach the required “throwing fitness” the athlete needs for the in-season load they will face. 

In other words we must plan the act of “throwing” and execute the act of “throwing” to induce change. This change or “adaptation” over time we can measure as “throwing fitness”. 

By Google's definition an adaptation is- “a modification of an organism or its parts that makes it more fit for the demand of a task.” 

Our goal is to make gradual positive modification or “adaptation” to the body through the act of throwing. In doing so we would call this improving “throwing fitness”. 


When looking at injury rates in the MLB we can see an interesting trend. The risk of injury drops as the season progresses. This study was conducted by Posner Et al. and titled “The Epidemiology of Major League Baseball Injuries”. Posner states in his conclusions that “The highest rate of injury was during the month of April”.

Posner et al: Epidemiology of Major League Baseball


This paper was counter to traditional belief that as season goes on our body wears down thus placing us at higher risk of injury. This data shows that the lack of proper progression into season may lead to a much higher risk of injury. The important take away is that with elevated injury rates and more year round play it is clear athletes are not progressing workload effectively into their season.

Standard linear throwing programs are not effectively allowing athletes to be ready for the year. Fatigue is sustained both early in the season and during season. According to Motus Global athletes are at approximately 25x higher risk of injury when throwing fatigued.

In this module we will discuss in depth how traditional fatigue monitoring systems such as “pitch counts” are failing us in todays game. Pitch counts, innings limits and linear throwing progressions are setting athletes up for failure.

In this module we will discuss the concepts of “Workload Management”. The objective approach of Workload is changing the game today by helping provide insights on how we can help athletes mitigate arm injury. #EveryThrowCounts

As a bonus to completing this module we will provide you some resources to seamlessly implement “Workload Management”.

So what actually happens to the body when we improve “throwing fitness”? Sure we make adaptations physically but what is going on and what is improving? It's clear that some sort of muscular adaptation has to be occurring right? To properly understand our goals to improve “throwing fitness” we must understand what is actually happening at an anatomical level. 

When measuring fitness changes we generally look at skeletal muscle and the changes imparted through activity. 

There are 2 forms of adaptation that can occur when we are talking about skeletal muscle. Endurance and Strength. Let's explore both Endurance and Strength to better understand the changes that occur under each adaptation. 

Let's begin by talking about the first adaptation. The adaptation of “Endurance”. 

There are 2 local changes that occur in the skeletal muscle when talking about “Endurance”…


1.Increased Mitochondrial Biogenesis- 

Research describes the increase of Mitochondrial Biogenesis as the following…

“The mitochondrion is the main organelle for energy production through the generation of adenosine triphosphate (ATP) via the electron transport system (ETS), using substrates generated in the tricarboxylic acid (TCA) cycle (Egan and Zierath 2013; Bishop et al. 2014). 

Recent studies have begun to looked at exercise-induced mitochondrial biogenesis adaptations from the perspective of mitochondrial content and function with varying exercise intensity paradigms (Serpiello et al. 2012; Granata et al. 2016a,b; MacInnis et al. 2016).

In simple terms the mitochondria generates ATP (the energy needed to contract a muscle). When there is more mitochondria there is more potential for muscular contraction. The more demand we have to maintain muscular contraction (exercise) for a longer period of time the more mitochondria we need. 


  1. Capillary Density-

Research explains the improvement of Capillary Density as…


“Aids in the body's ability to transport and use oxygen to generate energy and therefore delay the onset of muscle fatigue during prolonged exercise (Joyner and Coyle 2008).”

In simple terms capillary density is like the company Amazon. The more drivers you have the more packages you can deliver. Capillaries are the drivers and they deliver ATP to the muscles. Just like in the discussion of mitochondria you need greater capillary density as the demand becomes greater from the task. 


Now that we have covered endurance let's next talk about the adaptation of “Strength”. There are 4 local changes that occur in the skeletal muscle when talking about “Strength”…

  1. Neuromuscular Adaptation-

Research explains Neuromuscular Adaptation as… 


“Adaptations observed within the neuromuscular system have centered on increases in skill acquisition through the nervous system and increased maximal muscle activation by way of motor unit synchronization, muscle recruitment, and increased neural activation 

(Enoka 1988; Jones et al. 1989).”


In simple terms your brain improves on a task overtime. It learns to communicate with your muscles at better rates as it adapts and becomes more aware of the task. This requires exposure to the task and practice of the task through different variabilities. 


  1. Increase In Muscle CSA (Cross Sectional Area) (Size)


Research talks about the increase in muscle CSA as… 


“In terms of hypertrophy, the main focus for adaptation has been on increases in CSA for individual muscle fibers, adding sarcomeres in parallel. (Cureton et al. 1988; Frontera et al. 1988; Staron et al. 1990).”


In simple terms if you improve muscle size you have more contractile units, which gives your brain more contractile units to communicate with, thus you are able to produce more force. 


  1. Alterations In Connective Tissue Stiffness


When talking about strength adaptations research points out that… 


“Possible reflex adaptations related to high stretch loads in jumping and rapid reciprocal movements have also been revealed (Sale et al. 1988).”


In simple terms the connective tissues will have a larger reflex to stress which will result in a larger force output. A good example of this would be a rubber band. The thicker the rubber band the less far you have to pull it back to create the same amount of force as a thinner rubber band you have stretched much further. 


  1. RFD (Rate Of Force Development)


In research RFD is explained as the following… 


“The RFD refers to the rate of increase in force at the onset of contraction, that is, the slope of the force–time curve (Sleivert and Wenger 1994; Aagaard et al. 2002)


An early study by Aagaard and colleagues (2002) demonstrated a 15% increase in RFD after 14 wk of heavy strength training. In addition, there were increases in both EMG amplitude and rate of EMG increase with training, indicating an enhancement in neural drive.


This suggests that RFD is related to alterations in the neural drive. Other factors that contribute to RFD are muscle fiber type and force transfer. Studies on the role of fiber type indicate that type II fibers show a greater RFD (Korhonen et al. 2006; Aagaard et al. 2007); thus, increases in type II fiber CSAwith strength training would complement the increased neural drive (Staron et al. 1990, 1991; Mero et al. 2013).”

In simple terms you are able to produce more force in a shorter amount of time. This is especially prevalent in pitching where you only have a short amount of time to produce as much force as possible. 

Now that we understand the differences in the various adaptations that can occur through endurance or strength, let's talk about how we can induce change through a throwing program to develop “Throwing Fitness”.


When building a throwing program you can induce adaptation by either volume or intensity. That's it! It's simple. Volume or intensity. 

Volume is how much we do a task.

Intensity is how much effort we put into a task.

At the onset of a throwing program we can choose the volume and intensity progressions but we cannot induce strength or endurance adaptations exclusively. Due to the unique nature of throwing, the volume and intensity programmed in a throwing program will drive both strength and endurance adaptations. 

The act of throwing biases endurance adaptations over strength adaptations in most cases due to most throwing programs accumulating predominant amounts of volume at low intensities. 

This blurred line of which specific adaptations are occurring (strength or endurance) is where we identify the measured progression of “Throwing Fitness”. Throwing Fitness measures the load an athlete accumulates over a duration of time. This measure of Throwing Fitness assumes both strength and endurance progressions over that duration of time and does not require the identification of either individually as it scales the accounting of both in calculation. 

We can follow general guidelines that peak intensity with little to moderate volume will produce more strength adaptations for an athlete. On the other hand, more volume with low intensity can induce more endurance adaptation in throwing for most athletes. Again though we cannot state that at any time we are solely producing the adaptations of either strength or endurance. 


To conclude, let's summarize what we've learned surrounding the makeup of “Throwing Fitness”…

  1. Following a set progression of throwing volume and intensity develops adaptations in both strength and endurance athlete to athlete. 


  1. Due to the unique nature of throwing we cannot say specifically that the adaptations measured can be defined as any general fitness training as we see it in research. 


  1. For this we measure the progression of the act of throwing as developing “throwing fitness” and can measure the development of adaptation through this activity as the measure of “throwing fitness”. 
  2. Continued measure of throwing fitness should allow us to produce the needed 


You can't say you don't believe in workload management. We all believe in workload management. If I asked, "are you ready to run a marathon today?", you would give me some sort of short calculated answer based on how much training you've done to prepare for running a marathon. For most the answer is simple, "Im not ready for that... Im not built up!", they'll exclaim. 

Workload management is intuitive. It's simple. It comes down to this... Are you or are you not built up enough to handle performance. If you are not we need to know how to build you up gradually. If you are then we need to make sure we hold a routine to assure you maintain it during your competitive season. 

Ok. I'll acknowledge I said "workload is simple" and while its definitely intuitive at an overview level I wouldn't say its practices are always simple. For 5+ years KP has been scaling workload strategies daily with athletes all around the world and in this course our goal is to show you how. You'll get it, it is actually simple in practice and I can promise you this, once you get it you'll never look at throwing the same. 



The system is broken. The baseball industry has set you up for failure. It's getting worse, not better.

Lets awaken to the reality...

You are 

++++++Its not your mechanics! 


-travel teams are getting 30% kick back from showcase groups

-MLB is covering up pitch clock dangers because they want attendance to stay up 

-private spaces are widely marketing Velo programs direct to players and parents 

-college coaches are overusing players to assure they maintain a paycheck 

-youth parents are chasing exposure as early as 8 years old 




I believe we missed watching some of the best pitchers of all time play at the MLB level due to injury. Its very apparent we have missed the best years of some of the games top pitchers due to injury. I know kids are missing life changing opportunities to attend specific universities, achieve their dreams because of pitching injuries. We have an obligation to understand why. 

Overuse. Overuse. Overuse. We have a workload problem causing an injury epidemic in todays game. No one would argue the research. No one disagrees there is a problem...

Our study suggests there is a misunderstanding of the workload volume in the high school–aged baseball pitcher. Research has suggested that the occurrence of workload spikes (sudden increased volume relative to regular training volume) significantly increases risk for throwing-related injury.” -Zaremski et al
 "Recent studies have shown that pitch volume and overuse are central factors that lead to shoulder and elbow injuries in the young throwing athlete.” -Eric D. Parks
"Overuse is one of the most common etiologic factors that lead to injuries in the pediatric and adolescent athlete.” -Joel S. Brenner
“It is widely accepted that elbow injury results from overuse. High torques and forces in the joint stress the ligaments, and repetitive valgus overload from throwing may cause a micro-rupture. When overuse is sustained, and the body is unable to compensate, this can lead to attenuation or even tear of the UCL.” Trigt et al.

Its so bad that we have become numb to the conversation. We've given up hope on solving the problem. Its easier to just to accept the fate today than to seek a solution. 

"Well that's just part of being a pitcher today.. They have that Tommy John Surgery down to a science today it's really not that big of a deal." 




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