Throwing programs are often treated as tradition instead of load management. But newer reviews give a more useful framework. A 2023 systematic review on the biomechanical basis of interval throwing programs found that interval throwing can progressively build elbow varus torque toward the levels seen in full-effort pitching. In other words, progression works best when it builds capacity in a staged way rather than jumping directly from easy catch to full mound work.
At the same time, a 2025 systematic review of baseball interval throwing programs found substantial variability across published programs. That is a useful warning: many throwing programs look structured, but the field is not standardized enough for coaches to assume any printed progression is automatically the right one for their athlete.
What should progress first?
A good progression usually changes one stress variable at a time or at least avoids major jumps in several variables at once. The main levers are:
- Throw count or total volume.
- Throwing distance.
- Intent or effort level.
- Flat-ground versus mound work.
- Frequency across the week.
The mistake is to increase distance, effort, and frequency all at once because the athlete “looks good.” Tolerance is often delayed. The arm may feel okay today but not after the third jump in one week.
Why intent matters as much as distance
Two throws from the same distance can place very different stress on the arm depending on intent and mechanics. That is why a throwing program built only around distance markers can miss the real workload. The 2023 biomechanical review supports this point by showing that joint loading changes progressively as throwing demands change.
In practical terms, coaches should stop asking only “How far did you throw?” and start asking “How hard? How many? Off flat ground or a mound? How did you recover?”
What a sound progression usually includes
- Clear entry criteria, such as pain-free throwing and basic range of motion.
- Gradual increases in one or two stress variables at a time.
- Regular readiness checks, not blind advancement on the calendar.
- A defined transition from catch play to higher-intent work and then mound work.
- A plan for what to do if soreness or fatigue rises.
This is true for rehab throwing, preseason build-up, return after shutdown, and even in-season management. The details vary, but the logic stays the same: capacity should be earned, not assumed.
Progression should be individualized
Two pitchers can follow the same printed progression and respond very differently based on age, training history, velocity, movement quality, recovery, and total life stress. That is why progression should never be a pure calendar exercise. It should be a feedback exercise.
If you want a better way to organize throwing progressions, monitor readiness, and adjust workload in real time, download Pitch AI on iPhone or join the Android waitlist. Pitch AI helps pitchers follow a progression that responds to the athlete instead of forcing the athlete to obey a static schedule.