How fast should pitchers progress their training?

Progression sounds simple: do a bit more over time. In practice, the details decide whether a pitcher arrives at the season healthy and throwing harder or arrives sore and behind. This guide covers how loads should rise across weeks and how to sequence a throwing build-up, including how to recognize when the right move is backward.

Why waves beat straight lines

Tudor Bompa compared several ways of raising load across a training phase [1]:

• Standard loading keeps the same load all phase. It works early, then plateaus.
• Linear loading raises the load every week. It works briefly, then tips toward overtraining if you keep it up.
• Step loading (3:1) raises the load for three weeks, then drops it in the fourth. Blocks usually run about four weeks.
• Step loading for young athletes (2:1) uses two weeks up and one down, because younger athletes need more frequent unloading.

Bompa also warns that a sudden large jump in load delays adaptation, because the recovery needed grows with the size of the jump [1]. Within each week, Zatsiorsky's rule of thumb is that a light day or week should carry roughly 60 percent of the volume of the heaviest one [10]. Variation in load is part of the design, which is why part 3 of this series argues that improvement happens during recovery.

Is the 10 percent rule real?

The famous "never increase more than 10 percent a week" rule has much weaker evidence than its popularity suggests. In a randomized trial of 532 novice runners, a 13-week graded program built on the 10 percent rule produced the same injury rate as a standard 8-week program: 20.8 percent versus 20.3 percent [2]. That study involved runners, and its lesson carries over: the rate of increase alone does not guarantee safety. Sudden spikes and total exposure matter alongside it, which is why our guide to workload and arm health looks at the acute-to-chronic picture instead of a single percentage.

In what order should pitchers progress throwing?

Interval throwing programs, the return-to-throw protocols used after injury, offer the best-documented throwing progressions. They build distance on flat ground first, then move to the mound at increasing effort, and add breaking balls late [3, 4]. Axe and colleagues built age-specific programs from game data and let symptoms decide when a thrower advances [4]. A 2024 update by Reinold and colleagues rebuilt the classic program around measured workload: the original drifted outside the commonly used 0.7 to 1.3 workload-ratio range for 18 percent of the program, with a peak of 1.61, while the updated version lasted longer (217 days versus 136) and stayed outside that range only 9 percent of the time [9].

Pulling those principles together (our synthesis; nobody has tested it as a protocol), a healthy pitcher building toward high-intent work can change roughly one dimension at a time, in this order:

1. Distance: build catch and long toss distance at moderate effort.
2. Intensity: raise effort and velocity at distances the arm already tolerates.
3. Volume: add throws or sets once intensity holds.
4. Pitch mix: fastball first, changeup next, breaking balls later.
5. Context: flat ground to mound to bullpens, then live hitters and games.

That order is about workload on the arm. Low-intent grip play during catch can start much earlier, because it adds almost no stress. For a deeper walk-through see how to properly progress a throwing program.

Progress without guessing

Build workload one step at a time

Pitch AI ramps your throwing workload gradually and tracks how your arm responds. It logs every throwing session and builds workload progressively.

Farther is not always easier

Distance and stress are separate dials. In Fleisig's biomechanics study of college pitchers, maximum-distance long toss produced the highest elbow varus torque of any throw measured, about 100 newton meters, while hard throws on a line at 120 and 180 feet looked much more like pitching [5]. Adding distance late in a build is a real step up in load. Our long toss guide covers how to dose it.

Why "50 percent effort" fools you

Perceived effort is a poor intensity dial. At 120 feet, throws pitchers rated as 50 percent effort still produced 87 percent of maximum elbow torque at 78 percent of max velocity, and each 25 percent cut in perceived effort lowered torque only about 7 percent [7]. On the mound, 60 percent perceived effort produced about 76 percent of maximum force [8]. When throws were guided by a measured velocity target instead of feel, elbow torque came down more reliably [11]. If you can measure velocity, use a velocity target to set intensity during a build-up rather than a feeling.

Plan the steps back

Good progressions include rules for going backward. In interval programs, pain while throwing means stopping for the day, then dropping back a step after rest before advancing again [3, 4]. These rules come from clinical guidelines and expert consensus rather than trials, but they are the accepted standard.

Beyond pain, four signals suggest easing off before something breaks:

• Velocity falling at the same effort on a familiar drill.
• A readiness score or check-in that slides for several days.
• Sudden bodyweight loss during a heavy block.
• Next-morning heaviness that does not clear after an easy day.

Fatigue research supports these as warning signs, but none of them has a validated cut-off [6]. Treat them as reasons to repeat a week, and hold the numbers loosely.

A sample 8-week off-season shape

This example shows the shape of a 3:1 build for a healthy high school pitcher. Adapt it to the pitcher in front of you.

Younger pitchers can use the 2:1 version, with a lighter week every third week. In both cases, lifting follows the same wave, and the NSCA recommends starting plyometrics at low intensity and volume before progressing [12].

What to do this week

Write down which single dial you are moving this week and which ones you are holding. Put your next lighter week on the calendar now, before you feel like you need it. Then decide in advance what will make you step back. For lifting, part 2 of this series covers how much load to add. Part 5 covers when to change the exercises themselves.

Frequently asked questions

Build in waves

Let Pitch AI plan the steps forward and back

Pitch AI ramps your throwing workload gradually and tracks how your arm responds. Its daily Wellness Check-In asks about arm freshness and soreness and can reduce volume on days you are not ready.

References

1. Bompa TO, Haff GG (2009). Periodization: Theory and Methodology of Training, 5th ed. Human Kinetics.
2. Buist I, Bredeweg SW, van Mechelen W, et al. (2008). No effect of a graded training program on the number of running-related injuries in novice runners: a randomized controlled trial. American Journal of Sports Medicine, 36(1), 33-39. https://doi.org/10.1177/0363546507307505
3. Reinold MM, Wilk KE, Reed J, Crenshaw K, Andrews JR (2002). Interval sport programs: guidelines for baseball, tennis, and golf. Journal of Orthopaedic and Sports Physical Therapy, 32(6), 293-298. https://doi.org/10.2519/jospt.2002.32.6.293
4. Axe M, Hurd W, Snyder-Mackler L (2009). Data-based interval throwing programs for baseball players. Sports Health, 1(2), 145-153. https://doi.org/10.1177/1941738108331198
5. Fleisig GS, Bolt B, Fortenbaugh D, Wilk KE, Andrews JR (2011). Biomechanical comparison of baseball pitching and long-toss: implications for training and rehabilitation. Journal of Orthopaedic and Sports Physical Therapy, 41(5), 296-303. https://doi.org/10.2519/jospt.2011.3568
6. Halson SL (2014). Monitoring training load to understand fatigue in athletes. Sports Medicine, 44(Suppl 2), S139-S147. https://doi.org/10.1007/s40279-014-0253-z
7. Melugin HP, Larson DR, Fleisig GS, et al. (2019). Baseball pitchers’ perceived effort does not match actual measured effort during a structured long-toss throwing program. American Journal of Sports Medicine, 47(8), 1949-1954. https://doi.org/10.1177/0363546519850560
8. Slenker NR, Limpisvasti O, Mohr K, Aguinaldo A, ElAttrache NS (2014). Biomechanical comparison of the interval throwing program and baseball pitching: upper extremity loads in training and rehabilitation. American Journal of Sports Medicine, 42(5), 1226-1232. https://doi.org/10.1177/0363546514526152
9. Reinold MM, Dowling B, Fleisig GS, et al. (2024). An interval throwing program for baseball pitchers based upon workload data. International Journal of Sports Physical Therapy, 19(3), 326-336. https://doi.org/10.26603/001c.94146
10. Zatsiorsky VM, Kraemer WJ (2006). Science and Practice of Strength Training, 2nd ed. Human Kinetics.
11. Lizzio VA, Smith DG, Jildeh TR, et al. (2020). Importance of radar gun inclusion during return-to-throwing rehabilitation following ulnar collateral ligament reconstruction in baseball pitchers: a simulation study. Journal of Shoulder and Elbow Surgery, 29(3), 587-592. https://doi.org/10.1016/j.jse.2019.08.014
12. 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).

Related reading

• How to properly progress a throwing programVolume, distance and intent, one variable at a time.
• Long toss for pitchers: how far, how often, and whyDistance, torque and how to dose it.
• Pitching workload and arm healthSpikes, chronic load and the ACWR.
• The best throwing program for pitchersHow to choose one that fits.
• Should pitchers change their workout every few weeks?Part 5: variation and when to switch exercises.