In the past, we have discussed some of the KPIs and metrics the Driveline hitting department uses to both quantify athlete results and measure trainer performance. In the pitching department, we focus specifically on a handful of metrics, all of which we will discuss in forthcoming blog posts.
When determining which metrics to prioritize, we wanted to make sure that tracking and reporting these internally would help us assess whether our current training strategies and protocols were working while ALSO helping us evaluate the individual performances of our skill coaches. We hold each member of the department and ultimately the entire company accountable for these results.
Do athletes get better? How good are our skill coaches? Are we improving all aspects of pitching development? This is what matters to us.
Fastball velo gained
For now, we will focus on one thing: velocity. We know that velocity is one of the most important metrics in pitching. Previously, we have discussed how much value can be created by developing it at the minor league level. In addition, while it’s been a while since we did after-the-fact analyses of athlete results (2018 summer edition), as we gear up for the 2021 summer, we wanted to introduce a few from the last couple years.
This piece is strictly about how much fastball velocity was gained by pitchers who assessed, trained, and retested (at least once) at Driveline from roughly summer 2019 on. Of course, fastball velocity is not the be-all-end-all of player development, nor is it a focus for every single pitcher that walks through the doors at Driveline.
Nevertheless, it is an extremely important indicator of success at the major league level. To quote our past research on velocity’s impact on production: “A [MLB] pitcher who outperformed his fastball velocity projection [from 2013 to 2019] by +1 mph produced an RA9 that was .2443 points lower than expected, on average.”
Or, more simply, gaining fastball velo has an extreme impact on an athlete’s performance ceiling, so we take great care in monitoring it.
Velocity as a KPI
Given the variety of focuses of of our in-gym athletes, we standardize pitching floor velocity gains as a KPI using the velocities from our motion capture assessment. All athletes throw in the mocap lab on Day 1 (or when they are otherwise reasonably healthy and on-boarded up to game speed).
For retest purposes, we’ll generally retest players every 6 weeks (+/- a week or two) to assess mechanical changes and obtain a consistent measure of their throwing velocity. Thus, the numbers below reflect athletes who have trained here for at least 1 such training block, which we feel allows enough time—given the nonlinear nature of gains—to capture notable changes without the day to day variation that is natural in the course of training.
We’ll look at some general stats to get started.
The chart below shows statistics for the athletes who’ve trained at Driveline over the past two years. We see that the average starting velocity and velocity gained while training at DL both climb from 2019 to 2020 (offseason and summer training periods). This off-season, the average stay for athletes was longer, which can likely be credited to an increase in long-term trainees related to flexibility and uncertainty around COVID.
Similarly, with the facility shut down for the first half of the 2020 summer, no athletes were able to get in two training blocks before summer ended.
Looking more specifically at the distribution of velocity gains by seasonal training block rather than over the athlete’s entire stay, we see those increases from 2019 to 2020 remain consistent.
The 25th, 50th, and 75th percentile velocity gains (the dark orange vertical lines in the graphs above) are also indicated below.
Returning to velocity gains accrued during an athlete’s stay, the chart below groups athletes into mph increments and shows the number and overall percentage of athletes who fall into each increment.
Among athletes with at least one training block at Driveline, 52% gained more than 1 mph in their retest, 27% maintained about the same velo (+/- 1 mph), and 21% lost velocity in the last mocap retest of their stay.
We see that athletes who train at the facility for longer gain more velocity—on average—than those who stay for shorter periods of time.
Another notable trend that we’ve observed in the past and which holds true in this sample of athletes is that it’s generally tougher to gain velocity for hard throwers. This is due to a variety of factors, including the relative lack of low hanging fruit to address mechanically or physically, along with the fact that harder throwers may be more focused on other areas of development, such as pitch design, command, or simply getting game-like reps to prepare for the season.
A number of athletes have trained with us across multiple trips to the gym, often including online training in-between to continue working towards their goals.
To include the progress of these athletes over a longer time period, we can also compare all athletes’ first mocap on file (in this case since April 2019) with their most recent mocap.
The 25th, 50th, and 75th percentiles are again marked with dark orange lines and are shown in the table below—with athletes gaining 1.8 mph on average (mean gain).
As above, we can gain a bit more insight by also considering how long athletes had between their first and last mocaps.
We see athletes with a longer Driveline training history on average had greater gains across each of the buckets. For the 35 athletes who have trained with us over the course of several off-seasons or over a full gap year (more than 200 days between their first and last mocaps), we see average velo gains of 3.29 mph.
As referenced above, we see it’s more difficult for athletes to gain more velocity the harder they start off throwing. Even so, athletes who throw moderately hard are able to gain velocity on average (though these gains are naturally smaller than for athletes who start off throwing slower) over the long term.
Training for velocity is possible. We prove that here every single day and hold ourselves accountable, monitoring velocity gains as one of our Pitching Department’s main KPIs. If you want to throw harder, this is the best place in the world to help you do that.
Velocity is not the only thing
All that said, we know that velocity is not the only thing that matters with regards to being a successful pitcher and getting hitters out. Because of that, it is not the only thing the pitching department at Driveline focuses on when training athletes, and it is not the only KPI we use to evaluate our proficiency at improving performance.
In future posts, we will discuss our pitch design KPIs, Athlete Composite Scores, MPH per Varus tracking and how we quantify the athlete’s overall training experience.
Written by David Besky – Data Scientist, Alex Caravan – Director of Data Science and Bill Hezel – Director of Pitching