TLDR: - HSS is a product of passivity and orientation - HSS barely matters for taller pitchers - Close the gap quickly from peak HSS to BR - SSC/rubber band > spinning - Solutions > strategy (send energy to the arm) - Taller pitchers have wider affordances

Skinny pitchers are often told to gain weight to “protect their arm”, which could be not only baseless, but also dangerous for pitchers I analyzed each of the top factors for increased elbow and shoulder torque and distraction forces My findings & bodyweight deep dive🧵⬇️

My plan for this thread was to analyze arm slot specific stresses to assign truly individualized arm care; even accounting for velocity, this doesn't matter at all These are the top 10 factors for increased stress on the elbow and shoulder in both torque and distraction forces

Body mass is a top 4 metric for each of the 4 measures of stress even accounting for velo At the same velo, every 1lb of BW adds roughly 0.48 and 0.47Nm of elbow valgus and shoulder IR torque, along with 0.92 and 1.19 lbf of increased elbow and shoulder distraction forces

Stress itself isn't inherently good or bad, so I reviewed similar research to quantity body composition to see where adding mass becomes detrimental Pitchers need to gain ~70%+ lean tissue to neutralize added BW, and ~85%+ for a net negative stress on connective tissue (1,2,3)

However, strength outpaces mass and offsets fat. For untrained individuals this can look like theoretically handling as much as 22lbs of fat, while MLB veterans may be unable to continue adding strength to account for even roughly 0.5lbs of fat in an entire year (1,2,4)

TLDR: - Different arm slots = same stress - Fat don’t fly (or protect UCLs) - Strength > mass

I believe elbow valgus torque is an overrated metric, and does NOT accurately predict elbow stress. WILD claim to make, but here is my (3,000+ word notes app blog) attempt at defending that: (1/2)

Pleasing the masses. Blog debut: medium.com/@27jthorne/val…

The goal of mechanics is to transfer as much energy as possible through each segment and into the arm. I made reports to measure energy flow throughout the delivery, which can help identify and visualize this for athletes Here’s the 4 hardest throwers in drivelines open biomech

New blog on the nervous systemn. I look at the root cause of NS inputs to identify threat responses the nervous system must first navigate before it can even address the challenge of orchestrating a solution to increase velocity

medium.com/@27jthorne/the…

A pitcher's throw is governed by the nervous system, not forcing mechanical changes High velocity mechanics cannot emerge until the nervous system believes it can safely send more energy to the ball🧵⬇️

Velocity is the expression of what the nervous system allows, not what the player can force The primary goal of the nervous system is to ensure survival, not to execute pitches at 97mph A pitcher throwing 90 must address constraints that the nervous system perceives as a threat

Nervous system can view pain, strength limitation, injury history etc as a threat; a holistic assessment is needed to identify these Clearing underlying issues ensures we don't build on a foundation of mud A minor, un-rehabbed ankle sprain can affect the throw and arm for years

Ankle sprain & shoulder ER/scap retraction at foot plant can seem unrelated If single leg stability is a threat the nervous system will get to safety by "flying open", swinging lead leg into early FP The arm doesn't have a chance to get in position to accept energy & accelerate

A pitcher who pops Advil regularly may hit a small PR on one random day, but won't see consistent progress If the current velo provides a threat, the NS refuses to allow more energy You can only override this with stimulants and adrenaline... not suited for long term adaptation

Velocity growth is the NS ensuring the current velo is safe & allowing more energy into the arm First build an engine to produce copious energy Then refine the control center directing the energy or the NS will use “mechanical leaks” to get rid of excess energy it can't handle

In the full blog I discuss not only identifying but correcting deeper layers, how off-field habits set the nervous system's ceiling, & using motor learning to tap into what the nervous system allows Link in the reply to read the entire blog ⬇️

medium.com/@27jthorne/the…