Related Experiment Video
Updated: Apr 25, 2026

Measuring 3D In-vivo Shoulder Kinematics using Biplanar Videoradiography
Published on: March 12, 2021
A total motion release warm-up improves dominant arm shoulder internal and external rotation in baseball players
Stephen C Gamma1, Russell T Baker1, Steve Iorio2
1University of Idaho, Moscow, ID, USA.
Context:
Current literature indicates a correlation between decreased total shoulder range of motion (ROM) and internal rotation (IR) of the dominant arm and increased injury risk in throwers. The optimal method for increasing shoulder ROM, improving performance, and preventing injury is unknown. It is also unknown if treating the non-dominant arm may affect ROM on the dominant side.
Purpose:
To explore the effect of the Total Motion Release (TMR®) Trunk Twist (TT) and Arm Raise (AR) on IR and external rotation (ER) of the dominant shoulder in baseball players compared to a traditional dynamic warm-up.
Design:
Cohort study.
Setting:
University athletic training clinic and baseball field.
Participants:
Pitchers (males, n = 10; age, 18.6 ± 1.3) recruited from local baseball teams were randomly assigned two one of two groups: TMR® treatment group (TMRG; n = 5) or traditional warm-up group (TWG; n = 5).
Interventions:
Baseline IR and ER goniometry range of motion (ROM) measurements were recorded. The TMRG then completed the TMR® exercises and post-intervention measurements. The TWG completed a traditional static and dynamic warm-up (e.g., lunges, power skips, sprints, sleeper stretch) and then completed post-intervention measurements. Following the completion of those measurements, the TWG completed the TMR® Trunk Twist and Arm Raise protocol and had post-intervention measurements recorded once more.
Main Outcome Measures:
ROM measures for IR and ER of the dominant shoulder. Alpha level was set at p ≤ 0.05.
Results:
Significant differences were present for IR (p = 0.025) and ER (p = 0.014) between the TMRG and the TWG after initial intervention. Significant differences for IR were present in the TWG between baseline and TMR® intervention and traditional warm-up and TMR® intervention. For the TWG, changes in ER were not statistically significant at baseline, post-warm-up, or post- TMR® intervention. Significant differences were not present for IR (p = 0.44) or ER (p = 0.23) between groups once TMR® had been completed by both groups.
Conclusions:
TMR® produced larger increases in IR and ER of the throwing shoulder when compared to the TWG. Generalizability is limited, however, by the low number of participants in each group and a potential ceiling effect of attainable ROM gains. Future studies should examine if using a full TMR® treatment process is more beneficial. Additionally, future research should compare TMR® intervention to other warm-up activities or stretching protocols (e.g. resistance tubing, weighted balls) and examine its effect across other variables (e.g., injury rates, throwing velocity).
Level Of Evidence:
Clinical Evidence Based Level 2b.
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