Every off-season, thousands of pitchers ask the same question in different words: will this exercise make me throw harder? The honest answer is that some of it transfers, by very different amounts. Strength coaches call this transfer of training, and it is one of the best-studied ideas in sport science. Here is how it works, what the baseball research shows, and how to build a program where every block has a clear job.
What does specificity mean in training?
The body adapts to the exact demands you place on it. The more an exercise resembles the sport skill in movement pattern, speed, force direction and timing, the more of its gain carries over to that skill [1, 2]. Coaches shorten this to SAID, specific adaptation to imposed demands. The NSCA textbook adds an important caveat: specificity does not mean every exercise has to imitate the sport [1].
Zatsiorsky measures transfer as a ratio: the gain in the untrained task (your fastball) divided by the gain in the trained task (your squat). In one of his examples, two groups trained isometric leg strength at different knee angles. The group that made the bigger gain at its trained angle actually improved its squat less, because that gain transferred poorly [2]. Getting better at an exercise and getting better at the sport are related, and they are separate outcomes.
Bondarchuk's four classes of exercise
The Soviet hammer coach Anatoliy Bondarchuk built a whole system around transfer. He sorted exercises into four classes based on how closely they match the competitive action [3, 4]. Mapped onto pitching (our own mapping, built from his definitions):
| Class | What it is | Pitching examples |
|---|---|---|
| General preparatory | Neither the throw nor its parts; raises general work capacity | Squat, deadlift, presses, rows, conditioning |
| Special preparatory | Similar muscles and speeds without copying the throw | Rotational med-ball throws, lateral bounds, upper-body plyos |
| Special developmental | Repeats parts of the throw, at or above game demand | PlyoCare drills, weighted and underweight balls, long toss |
| Competitive | The event itself | Bullpens with intent, live at-bats, games |
Translations of Bondarchuk differ on the exact labels ("specific" versus "special"), but the logic is consistent: the closer you move toward competitive work, the more direct the transfer and the more stress each rep puts on the throwing arm.
Why a 5-ounce ball changes the math
The weight of the implement decides how much maximal strength matters. Zatsiorsky notes that elite shot-putters spend about half their training time on heavy resistance work, while javelin throwers spend only 15 to 25 percent, because a light implement depends more on speed than on force [2]. A javelin weighs about 800 grams. A baseball weighs about 145. That puts pitching at the extreme light end of the throwing family, where moving fast matters more than pushing hard.
This is why "more squat equals more velo" breaks down for advanced pitchers. Heavy lifting raises the ceiling, but converting that ceiling into arm speed takes faster, more specific work.
What pitching studies say about transfer
Special preparatory work: modest, real gains
In a randomized trial of 68 high school players, six weeks of shoulder resistance or upper-body plyometric work (three days a week) raised throwing velocity by 1.2 to 2.0 percent, while the control group did not change, and no program clearly beat the others [5]. In 24 Division I players, eight weeks of "Ballistic Six" upper-body plyos moved velocity from about 83 to 85 mph compared with controls [6]. These are useful gains, roughly one to two miles an hour, and they come without extra throwing stress.
Special developmental work: bigger effects, weaker evidence
Weighted and underweight ball programs sit closer to the throw. A systematic review found that seven of ten studies reported velocity gains, ranging from about 2 to over 11 mph, but every included study carried a high risk of bias [10]. In a randomized trial of 38 pitchers aged 13 to 18, the trained group gained about 3.3 percent, though the difference versus controls was not statistically significant, and 4 of 17 trained pitchers had elbow injuries versus none in the control group [11]. Closer to the throw means more transfer and more load on the arm. Our weighted ball guide covers dosing.
General strength: a strong correlate
General work still earns its place. In 33 Division I pitchers, body mass (r = 0.58) and absolute countermovement jump power (r = 0.43) were among the strongest correlates of in-game fastball velocity, while jump height and power relative to bodyweight were not [7]. In 19 Division I pitchers, jump impulse correlated with fastball velocity at r = 0.71 [8]. Rotational med-ball throw velocity tracked pitching velocity in Division III players [12], and a scoping review of 34 studies found that bodyweight and jump performance are consistently associated with pitching performance [13].
Read these carefully. They are cross-sectional correlations in small samples. They tell you that bigger, more powerful pitchers tend to throw harder. They do not prove that adding 50 pounds to your squat adds a specific number of miles per hour. No trial has shown that.
One plan, every class of work
Strength, workload and velocity work in one place
Pitch AI builds strength, workload and velocity work into one plan around your season, so your lifting, plyos and throwing days stop competing with each other.
Does lifting weights make you throw harder?
Indirectly, often yes. Zatsiorsky calls the mechanism "delayed transmutation": general fitness gained in one block gets converted into specific performance in later, more specific blocks [2]. Lifting builds the muscle mass and force capacity, and plyos, med balls, jumps and throwing teach the body to express it fast. Driveline makes a related practitioner point: skill on one lift does not carry over one-to-one to another, so they suggest picking one deadlift variation and sticking with it rather than chasing every variant [14].
The common mistake runs the other way: "make it look like pitching." Cable throwing motions and light band arm swings look specific, yet they match neither the speed nor the force of a real throw. Dynamic correspondence asks about force size, speed and timing, along with shape [4]. Looking similar is the weakest form of specificity.
How specific should a pitcher's training be?
It depends on your level. For a beginner, almost any training helps, and a 13-year-old can gain velocity from simply getting stronger and growing [2]. Advanced athletes need more specific means to keep improving. Even so, Bompa recommends that advanced athletes keep roughly 20 to 40 percent of training general, because general work maintains the base and supports recovery [9].
A practical way to use this:
- Youth and early high school: lean general. Learn the lifts, build strength and coordination, play catch with intent, and keep throwing specialization modest. See our youth pitcher development guide.
- Developing high school arms: add special preparatory work (med balls, jumps, upper-body plyos) on top of a solid strength base.
- Advanced high school and college: layer in special developmental work such as PlyoCare drills and structured long toss, plus carefully dosed weighted balls if your arm is ready, with the general base kept in place.
- Everyone: remember that competitive work (bullpens, live at-bats) is the most specific stimulus and the most stressful. Count it.
What to do this week
Take your current program and label every exercise with one of the four classes. If nearly everything is general, add two special preparatory pieces, such as a rotational med-ball throw and a lateral bound, twice a week. If nearly everything is special developmental or competitive, you are probably carrying a lot of arm stress with too little base underneath it, so protect two lifting days. Then track one velocity number on a fixed drill so you can see whether the mix is working. Part 7 of this series, why pitchers should measure velocity and track their lifts, explains how. For the overall picture of where velocity comes from, see what makes pitchers throw harder.
This is part 1 of our training principles series. Part 2 covers why velocity stops going up even when you keep doing the same work.
Frequently asked questions
Does squatting increase pitching velocity?
Squatting builds lower-body strength and mass, which are associated with higher velocity in college pitchers [7, 8], but no trial shows that a stronger squat adds a set number of miles per hour. Strength tends to show up on the mound when it is followed by faster, more specific work like jumps, med balls, plyos and throwing.
What is the SAID principle?
SAID stands for specific adaptation to imposed demands. The body adapts to what you ask it to do, so the closer an exercise matches the throw in movement, speed, force and timing, the more of its gain carries over [1, 2].
Do plyometrics help pitchers throw harder?
In controlled trials, six to eight weeks of upper-body plyometric work added roughly 1 to 2 percent velocity in high school players and about 2 mph in college players [5, 6].
Should young pitchers do sport-specific training?
Young pitchers gain from almost any well-coached training, so a general base of strength, coordination and catch play is the priority. Specific work becomes more important as training age rises, though even advanced athletes keep some training general [2, 9].
Train for transfer
Build a program where every block has a job
Pitch AI builds strength, workload and velocity work into one plan around your season, logs every throwing session and builds workload progressively, so general strength and specific throwing work arrive in the right order.
References
- Haff GG, Triplett NT, eds. (2016). Essentials of Strength Training and Conditioning, 4th ed. NSCA / Human Kinetics. Ch. 17 (Sheppard JM, Triplett NT) and Ch. 18 (Potach DH, Chu DA).
- Zatsiorsky VM, Kraemer WJ (2006). Science and Practice of Strength Training, 2nd ed. Human Kinetics.
- Bondarchuk AP (2007). Transfer of Training in Sports, Vol. I. Trans. Yessis M. Ultimate Athlete Concepts.
- Brearley S, Bishop C (2019). Transfer of training: how specific should we be? Strength and Conditioning Journal, 41(3), 97-109. https://doi.org/10.1519/SSC.0000000000000450
- Escamilla RF, Ionno M, deMahy MS, et al. (2012). Comparison of three baseball-specific 6-week training programs on throwing velocity in high school baseball players. Journal of Strength and Conditioning Research, 26(7), 1767-1781. https://doi.org/10.1519/JSC.0b013e3182578301
- Carter AB, Kaminski TW, Douex AT Jr, Knight CA, Richards JG (2007). Effects of high volume upper extremity plyometric training on throwing velocity and functional strength ratios of the shoulder rotators in collegiate baseball players. Journal of Strength and Conditioning Research, 21(1), 208-215. https://doi.org/10.1519/00124278-200702000-00038
- King BW, Snow TK, Millard-Stafford M (2025). Peak lower-extremity power unadjusted for body mass predicts fastball velocity in collegiate baseball pitchers. Journal of Strength and Conditioning Research, 39(2), 217-226. https://doi.org/10.1519/JSC.0000000000004966
- Sakurai M, Qiao M, Szymanski DJ, Crotin RL (2024). Countermovement jump and momentum generation associations to fastball velocity performance among Division I collegiate pitchers. Journal of Strength and Conditioning Research, 38(7), 1288-1294. https://doi.org/10.1519/JSC.0000000000004776
- Bompa TO, Haff GG (2009). Periodization: Theory and Methodology of Training, 5th ed. Human Kinetics.
- Caldwell JE, Alexander FJ, Ahmad CS (2019). Weighted-ball velocity enhancement programs for baseball pitchers: a systematic review. Orthopaedic Journal of Sports Medicine, 7(2), 2325967118825469. https://doi.org/10.1177/2325967118825469
- Reinold MM, Macrina LC, Fleisig GS, Aune K, Andrews JR (2018). Effect of a 6-week weighted baseball throwing program on pitch velocity, pitching arm biomechanics, passive range of motion, and injury rates. Sports Health, 10(4), 327-333. https://doi.org/10.1177/1941738118779909
- Taniyama D, Matsuno J, Yoshida K, Pyle B, Nyland J (2021). Rotational medicine ball throw velocity relates to NCAA Division III college baseball player bat swing, batted baseball, and pitching velocity. Journal of Strength and Conditioning Research, 35(12), 3414-3419. https://doi.org/10.1519/JSC.0000000000004148
- Mercier MA, Tremblay M, Daneau C, Descarreaux M (2020). Individual factors associated with baseball pitching performance: scoping review. BMJ Open Sport and Exercise Medicine, 6(1), e000704. https://doi.org/10.1136/bmjsem-2019-000704
- Boddy K, Daniels M (2017). Hacking the Kinetic Chain: Advanced Pitching. Driveline Baseball.