This original research by Reinold and colleagues presents an updated interval throwing program for baseball pitchers returning to sport after injury or surgery, including UCL reconstruction and Tommy John rehabilitation. Traditional interval throwing programs have been used for decades, but most were developed from clinical experience rather than modern biomechanical data. The purpose of this study was to create a more current, evidence-informed program based on throwing workload and elbow torque, and then compare it with a widely used traditional program.
To do this, the authors analyzed the workload demands of the original program by estimating elbow varus torque at different throwing distances and calculating daily, acute, and chronic workloads, along with the acute-to-chronic workload ratio (ACWR). They then designed a new program that better reflects how modern pitchers throw and progress during rehabilitation.
The results showed meaningful differences between the two models. The original program lasted 136 days and reached a final chronic workload of 15.0, but its ACWR moved outside the commonly referenced safe range of 0.7 to 1.3 for 18% of the program, peaking at 1.61. The updated program lasted 217 days and reached a lower final chronic workload of 10.8, while falling outside the safe range only 9% of the time, with a peak of 1.33. This suggests the new program builds throwing stress more gradually and with fewer workload spikes.
Overall, the study supports a more progressive, workload-based return-to-throwing approach for baseball pitchers. The updated program appears to be more consistent with current throwing demands and may help reduce setbacks or reinjury during rehabilitation.
Read the full original research here: https://ijspt.scholasticahq.com/article/94146-an-interval-throwing-program-for-baseball-pitchers-based-upon-workload-data