A TOTAL MOTION RELEASE WARM‐UP IMPROVES DOMINANT ARM SHOULDER INTERNAL AND EXTERNAL ROTATION IN BASEBALL PLAYERS

Abstract

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

INTRODUCTION

Total Motion Release (TMR®) is an innovative paradigm used to evaluate and treat body motion imbalances that is related to the concept that the body is a unified system striving to maintain a dynamic center of gravity.¹ Therefore, pain or dysfunction in one area of the body may be affected by movements that take place elsewhere. Patients use a 1 (i.e., no dysfunction, pain, or asymmetry) to 100 (i.e., complete dysfunction, pain, or asymmetry) scale to describe the imbalances across different measures (e.g., pain, strength, quality/quantity of motion) to generate their score for each of the prescribed motions in the TMR® screening. In standard TMR® treatment, six motions (i.e., arm raise [shoulder flexion], bent arm wall push [single arm push‐up], trunk twist [rotation], single‐leg sit‐to‐stand, leg raise [hip flexion], and weight‐bearing toe‐reach [unilateral bent knee squat]) are compared bilaterally and the motion with the greatest imbalance is treated first, providing that both sides are not perceived as dysfunctional. Total Motion Release® treatment includes repetitions, static holds, or some combination thereof and should be performed to the good side, (i.e., the side of ease) which is a departure from traditional therapies.¹ In standard TMR®, the data (i.e., progress) is evaluated every two sets of exercises. Based on the results of the treatment, the clinician decides to continue with that motion, modify the motion, or move to the next area of imbalance. Treatment then progresses to the second highest imbalance score and continues until the six main motions are balanced. A general recommendation is to resolve one upper body, trunk, and lower body imbalance each treatment to maximize treatment effect and retention of gains.¹

Baseball players strive to position their bodies in optimal alignment in order to accelerate and decelerate the throwing arm at high velocities during execution of the throwing motion.² Baseball players require the coordination of large forces from the lower to the upper extremities in order to generate extreme linear and angular velocities at ball release.³ The repetitive throwing motion has the potential to cause increased mechanical stress to the arm due to torque and distraction forces.^4,5 The glenohumeral and elbow joints are subjected to these stresses over multiple innings, games, and seasons during the span of a player's career.^6,7

Commonly, baseball players have been noted to possess decreased trunk rotation, shoulder internal rotation (IR) of the throwing arm, external rotation (ER) of the dominant hip, and IR of the non‐dominant hip.^2,8 Internal rotation of the non‐dominant hip may play a role in deceleration of the body during the throwing motion. Thus it may be plausible that decreased IR of the non‐dominant hip may transfer some of the demands of deceleration to the shoulder, resulting in less force dissipation through the trunk, thereby increasing forces at the shoulder.⁸ The presence of range of motion (ROM) deficits and movement compensation may alter arm slot, proper shoulder‐hip separation, and rhythmic timing, all of which may contribute to increased risk of injury.^9,10 Normal shoulder ROM within the general population include ER ranges from 90‐100° and IR ranges from 80‐90°, however, baseball players may present with a shoulder ER in excess of 110° and shoulder IR as low as 50‐60°.^11,12 Glenohumeral Internal Rotational Deficit (GIRD) is a loss in internal shoulder rotation compared to the opposite side and is usually identified when there is a loss of 10% of the total rotational motion of the opposite shoulder or a 25° difference between shoulders.^10,13,14 Loss of IR in the shoulder of a baseball player has been attributed to a number of potential factors including a posterior inferior capsular contracture, tightness of the external rotators, and osseous adaptations of glenoid and humerus.^15,16,17

While the underlying cause of GIRD may be debated, it is generally accepted that its presence is a predisposition for injury. Specifically, an IR deficit of greater than 25° has been described as having the potential to increase the risk for injury.^18,19 Wilk et al.²⁰ demonstrated pitchers with GIRD were nearly twice as likely to be injured and pitchers with total rotational motion deficit greater than 5° had a higher rate of injury compared to those without such deficit. The researchers concluded that, compared with pitchers without GIRD, pitchers with GIRD appear to be at a higher risk for injury and shoulder surgery. Myashita et al.²¹ also demonstrated that a significant increase in the ratio between ER and maximum shoulder external rotation (MER) is a risk factor for elbow injuries in baseball pitchers.

Another component that may need to be considered is that the deceleration phase of the throwing motion is initiated by IR of the non‐dominant hip.⁸ Thus, it is plausible that a lack of IR in the non‐dominant hip has the potential to produce the undesirable effect of transferring deceleration demands up the kinetic chain to the shoulder. As a result of decreased force dissipation through the trunk, the athlete may experience increased forces at the shoulder. In turn, the athlete with limited non‐dominant hip IR may be at an increased risk for shoulder injury.⁸ McCulloch, Patel, Ramkumar, Noble and Lintner²² demonstrated that pitchers possessed excessive IR on the stance (i.e., dominant) hip and excessive ER on the stride (i.e., non‐dominant) hip. As a compensation for inappropriate hip and trunk rotation, the patient may develop increased ER of the dominant shoulder; excessive ER may increase soft tissue forces and predispose the pitcher to shoulder injury.^2,8

Baseball specific warm‐ups vary in design and selection of exercises based on level of competition, setting, and coaching/medical staff. Common warm‐ups may include a progressive run, lunge with rotation and reach variations, explosive skips, shuffles, sprints, and stretching in attempt to prepare the entire body for throwing and injury prevention.²³ Variation exists, however, as some warm‐up strategies include light jogging, light throwing, and stretching²⁴ and others require longer distance jogging (i.e. 5 minutes), joint specific mobility exercise, and dynamic flexibility.⁴ Typically, these program take 15 to 20 minutes to complete, with the stated goal of increasing core temperature, decreasing fluid viscosity and increasing hip and trunk mobility.^23,25 In short, general warm‐up baseball protocols tend to vary by team and sports medicine staff without established evidence for effectiveness.

The purpose of this study was to compare the acute effects of a standard baseball warm‐up protocol to the implementation of the Total Motion Release (TMR®) Trunk Twist and Arm Raise protocol on internal and external ROM in the dominant arm of baseball players.

METHODS AND PROCEDURES

A pretest‐posttest randomized cohort design was utilized, with the sample consisting of male high school and collegiate baseball athletes (males; n = 10; age = 18.6 ± 1.3 years, age range = 16 to 20 years; experience = 9 collegiate and 1 high school players; right handed = 8, left handed = 2). All participants had at least five years of previous baseball experience and were not receiving treatment for a recent upper extremity injury (i.e., within that last 12 months). The study was conducted during the season, in a single session for each group, and was completed prior to baseball/warm‐up activities for the day. All participants provided written informed consent/assent and the study was approved by the Institutional Review Board.

Participants were randomly assigned to either a traditional warm‐up group (TWG) or the TMR® group (TMRG), with five participants in each group.

PROCEDURES

Baseline IR and ER goniometry ROM measurements were recorded for participants in both groups prior to intervention. Goniometric assessment of shoulder IR and ER was conducted with the participants lying on the exam table, with their shoulder abducted to 90° and their elbow flexed to 90°. The landmarks used for assessment were the olecranon process (fulcrum), long axis of the ulna (movement arm), and the perpendicular axis to the floor (stationary arm). Initial baseline measurements were recorded by a Certified Strength and Conditioning Specialist (CSCS) with a four years of professional experience in collegiate and professional baseball and were validated by an Athletic Trainer with five years of professional experience.

Following baseline measurements, the TMRG completed 3 sets of a 30 second standing Trunk Twist (TT) to their reported “good” side, with a 60 second rest period between each set (Figure 1). Coaching cues were given throughout each set, instructing the athlete to take a deep inhalation followed by deep exhalation when a new barrier was reached and to “unlock” the body segment that the participant perceived to be limiting motion (e.g., flex right knee if twisting to the left shoulder). Following TTs, each participant completed 2 sets of 30 second standing Arm Raise (AR) to the “good” side, with a 60 second rest between each set (Figure 2). Similar instructional cues were used when performing the Arm Raise, but the focus was on the patient reaching further into shoulder flexion. The entire TMR® TT and AR protocol took 8 to 10 minutes to complete depending on the time needed to explain the TMR® procedure to the participant. After both TMR® movements were completed, post‐intervention ROM measurements were recorded for comparison to baseline, in the same manner they were initially recorded.

Figure 1.

Standing Trunk Twist.

Figure 2.

Seated Arm Raise.

After baseline measurements were recorded, the TWG participated in a traditional 15‐minute dynamic warm‐up (Table 1). As there is significant variation in baseball warm‐up activities, the researchers utilized this warm‐up protocol because it was already being used by the participants’ to prepare for baseball activities and allowed for the participants to maintain consistency and regularity in sport activity. Once finished, the participants immediately had post‐intervention ROM measurements recorded for a baseline comparison, in the same manner they were initially recorded. Upon completing the post‐warm‐up measurements, the TWG then completed the TMR® protocol (i.e., TT and AR exercises, Figures 1 and 2). After performing both activities, the ROM measurements were recorded once again for the TWG group for comparison to baseline and post‐exercise measures. The null hypothesis was the TMR® protocol would produce superior outcomes compared to the traditional warm‐up protocol. Based on this and the small sample size of the cohort, the decision was made a priori to perform the TMR® protocol on the TWG to ensure the results did not occur due to the participant groups being different after randomization.

Table 1.

Traditional Warm‐up Protocol

Warm‐up Exercise	Repetitions
Walking Knee Hug	10 Yards
Forward Lunge w/ Rotation	10 Yards
Reverse Lunge w/ Rotation	10 Yards
Quad Stretch w/ Reach	10 Yards
Power Skips	10 Yards
Lateral Lunges	10 Yards
Sprint (50%)	2 × 30 Yards
Sprint (75%)	1 × 30 Yards
Sprint (100%)	1 × 30 Yards
Supine Sleeper Stretch*	2 × 30 Seconds**

^*Supine Sleeper Stretch with arm at 90° horizontal abduction

^**Each set of the Sleeper Stretch was separated with a 60 second rest period**

STATISTICAL METHODS

An independent sample t‐test was used to calculate the difference between groups from baseline. A repeated measures ANOVA was performed to analyze the difference in the TWG group from baseline to post‐warm‐up to post‐TMR®. An independent sample t‐test was used to analyze the difference between group means for the TMRG and the TWG following the completion of the TMR® protocol in both groups.

RESULTS

The TMRG and TWG did not demonstrate differences in age (18.8 ± 1.79 vs. 18.4 ± 0.55 yr, p = 0.65), IR (66° ± 12.06° vs. 78.8° ± 12.15°, p = 0.13), or ER (82.4° ± 11.33° vs. 83.6° ± 12.22°, p = 0.87) at baseline. An independent sample t‐test was used to analyze the difference between group means for the TMRG and the TWG following the initial warm‐up interventions. Significant differences were present for both internal and external shoulder rotation between the groups (p<.05). The use of TMR® produced larger increases in mean IR (19.2° ± 10.78° vs. 2.2° ± 8.73°, p = 0.03) and mean ER (13.6° ± 5.98° vs. ‐1.8° ± 9.20°, p = 0.01) of the throwing shoulder, irrespective of whether TMR® was applied to the dominant shoulder (Table 2, Figures 3 and 4). Of note, 60% of the participants in the TMR® group did not perform the AR pattern to their dominant side, but still experienced the improvement in IR and ER on the dominant side.

Table 2.

Group Means Data: Change in IR and ER of the Dominant Shoulder.

Shoulder ROM	TMRG	TWG	p ‐Value	Cohen's D	95% CI
Change in IR	19.2° ± 10.78°	2.2° ± 8.73°	0.025	1.73	2.69, 31.30
Change in ER	13.6° ± 5.98°	‐1.8° ± 9.20°	0.014	1.98	4.10, 26.70
	Values presented are mean ± SD.

TMRG = Total Motion Release Group; TWG = Traditional Warm‐Up Group.

Figure 3.

Pre and Post Intervention Mean IR ROM of the Dominant Shoulder ± SEM for TMRG and TWG.

Figure 4.

Pre and Post Intervention Mean ER ROM of the Dominant Shoulder ± SEM for TMRG and TWG.

A repeated measures ANOVA was used to analyze the difference across time to determine the effect of the traditional warm‐up versus the TMR® warm‐up on ROM for the TWG (Table 3 and 4; Figure 5). A significant main effect for time was identified (F_2,8 = 32.8, p ≤ 0.00, η² = .891) for IR. For the 5 participants in the TWG, the mean IR at baseline (M = 78.8°, SD = 5.43°) and post‐warm‐up (M = 81°, SD = 3.86°) were not statistically significantly different (Table 3). The differences between mean IR at baseline (M = 78.8°, SD = 5.43°) to post‐TMR® (M = 103°, SD = 2.36°) and post‐warm‐up (M = 81°, SD = 3.86°) to post‐ TMR® (M = 103°, SD = 2.36°) were statistically significantly different (Table 3). A significant main effect for time was not identified (F_2,8 = 4.3, p = 0.54, η² = .519) for ER. For the 5 participants in the TWG, the difference between mean ER from baseline (M = 83.6°, SD = 12.21°), post‐warm‐up (M = 81.8°, SD = 18.21°), and post‐ TMR® (M = 96.6°, SD = 9.79°) were not statistically significantly different (Table 4). The TMRG did have a larger increase in ER following TMR® that approached significance, but did not meet the a priori p‐value (p = .05). Of note, 40% of the participants in the TWG did not perform the AR pattern on their dominant side, but still experienced the improvement in IR and ER on the dominant side.

Table 3.

Change in IR of the Dominant Shoulder in the TWG over Time.

Time	Mean Difference	p‐Value	95% CI
Baseline to Post‐Warm‐up	2.20° ± 3.90°	1.00	−13.26, 17.66
Post‐Warm‐up to Post‐TMR	22.00° ± 1.58°*	0.00	15.74, 28.26
Baseline to Post‐TMR	24.20° ± 3.88°*	0.01	8.84, 39.56

Values presented are mean ± SD.

^*denotes statistically significant difference.

TMRG = Total Motion Release Group; TWG = Traditional Warm‐Up Group.

Table 4.

Change in ER of the Dominant Shoulder in the TWG over Time.

Time	Mean Difference	p‐Value	95% CI
Baseline to Post‐Warm‐up	−1.80° ± 4.12°	1.00	−14.50, 18.10
Post‐Warm‐up to Post‐TMR	10.80° ± 4.93°*	.028	−8.74, 30.64
Baseline to Post‐TMR	9.00° ± 2.30°	.052	−0.12, 18.12

Values presented are mean ± SD.

^*denotes statistically significant difference.

TMRG = Total Motion Release Group; TWG = Traditional Warm‐Up Group.

Figure 5.

Baseline, Post‐Warm‐up, and Post‐TMR Mean Internal and External Rotation of the Dominant Shoulder ± SEM for the TWG.

An independent sample t‐test was used to analyze the difference between group means in IR and ER of the dominant shoulder for the TMRG and the TWG following the completion of the TMR® protocol in both groups. Significant differences were not present for either internal (19.2° ± 10.78° vs. 24.2° ± 8.67°, p = 0.44) or external shoulder (13.6° ± 5.98° vs. 9.0° ± 5.14°, p = 0.23) rotation between the groups following the completion of the TMR® protocol. The use of TMR® produced essentially equal increases in IR and ER of the throwing shoulder, irrespective of whether the TMR® protocol was applied to the dominant shoulder, applied in isolation, or applied after the warm‐up between groups (Table 5, Figures 6 and 7). Additionally, the use of TMR® corrected and improved any loss of ROM experienced following the use of the traditional warm‐up protocol.

Table 5.

Group Means Data: Change in IR and ER of the Dominant Shoulder for Complete Intervention.

Shoulder ROM	TMRG	TWG	p ‐Value	Cohen's D	95% CI
Change in IR	19.2° ± 10.78°	24.2° ± 8.67°	0.44	−0.51	−19.27, 9.27
Change in ER	13.6° ± 5.98°	9.0° ± 5.14°	0.23	0.82	−3.51, 12.71
Values presented are mean ± SD.

TMRG = Total Motion Release Group; TWG = Traditional Warm‐Up Group.

Figure 6.

Pre and Post Total Intervention Mean IR ROM of the Dominant Shoulder ± SEM for TMRG and TWG.

Figure 7.

Pre and Post Total Intervention Mean ER ROM of the Dominant Shoulder ± SEM for TMRG and TWG.

DISCUSSION

In this study, a significant increase in ROM in bilateral shoulder internal and external rotation occurred in the TMRG compared to the TWG was observed. Additionally, ROM deficits (i.e., decreased ER) recorded following the traditional warm‐up were improved upon with the addition of the TMR® protocol. Another interesting outcome is that the TMR® warm‐up took over 5 minutes less time to complete than the traditional warm‐up and was often performed on the non‐dominant side (i.e., the AR pattern was performed on non‐dominant arm in 60% of the TMRG participants and 40% of the TWG participants). The use of the TMR® protocol to produce significantly greater ROM improvement in less time, without clinician assistance, and while treating the non‐dominant side provides potentially meaningful clinical and practical implications for intervention strategies aimed at improving IR and ER of the dominant arm in baseball players. Also, unlike the results found in the TWG after utilizing the traditional warm‐up program, the use of TMR® (which is performed to the good side) did not appear to create further ROM discrepancies, but rather improved total ROM and the ratio between IR and ER of the shoulder. Irrespective of the order, both groups experienced similar results after completing the TMR® protocol. Clinically, this is significant because a short intervention, applied to the “good” side, can produce a large ROM increase in the dominant shoulder and resulted in improvements to both IR and ER; however, the long‐term effects and impact on performance of this TMR® protocol are unknown.

Laudner, Sipes, and Wilson²⁶ examined the acute effects of the clinician‐assisted sleeper stretch and found performing 3 sets of a 30‐second stretch resulted in 3.1° and 2.3° improvement in IR ROM and horizontal adduction ROM of the shoulder, respectively. Oyama, Goerger C, Goerger B, Lephart and Meyers²⁷ utilized a passive stretch protocol that consisted of a horizontal cross‐arm stretch, a standing sleeper stretch with the arm at 90° of abduction, and a standing sleeper stretch with the arm at 45° abduction. All of the stretches were performed for 3 sets with a 30‐second hold that resulted in a mean improvement of 4.3° in internal shoulder rotation. Sauers, August, and Snyder²⁸ produced a statistically significant change in ER (average gain of 7.6°) and IR (average gain of 9.2°) using the Fauls modified stretching routine to produce acute increases in shoulder complex ROM. Moore, Laudner, McLoda, and Shaffer²⁹ used a single application of Muscle Energy Technique (MET) that consisted of a 5‐second isometric contraction at 25% maximal against examiner provided force, followed by the examiner applying a 30‐second active assisted stretch for a total of 3 repetitions to improve shoulder IR ROM. Participants gained an average of 4.2° following the intervention.²⁸

In the current study, the TWG experienced ROM changes similar to previously published research examining traditional techniques to improve acute ROM after the initial warm‐up protocol.^27,28,29 The TMRG, in contrast, experienced changes that were largely superior for increasing IR and ER ROM of the shoulder. Additionally, the TWG experienced larger increases in ROM following TMR® treatment; however, the ER changes were not statistically significant. The lack of a statistically significant change may be due to the small sample size or the potential ceiling effect in ER as this population is known to have increased ER when compared to the general population.³⁰ Following the completion of the TMR® protocol, both groups experienced similar gains which provides support for TMR® warm‐up (protocol) being an effective intervention at addressing ROM deficiencies in this group of participants. Although not a purpose of this study, participants also reported feelings of increased ease during throwing and anecdotal reports of increased velocity following TMR® interventions. These anecdotal reports warrant further investigation in future research studies.

LIMITATIONS AND FUTURE RESEARCH

As with all studies, limitations were present. The small sample size presents the risk of an unintentional sampling bias and increases the risk of Type II error. The small standard deviations and strong effect sizes (e.g., Cohen's D), however, provide a level of confidence that the results are true for our sample, are the result of the intervention applied, and are likely to continue to be found if a larger sample had been studied.³¹ Additionally, the lack a position‐specific warm‐up protocol may limit the generalizability to all baseball players or warm‐up protocols. Future studies that examine if using a full TMR® treatment process is more beneficial and if TMR® treatment is region specific (e.g., using the TT primarily increases shoulder ROM versus hip ROM) are needed. Additionally, future research should compare TMR® intervention to other warm‐up activities or stretching protocols that include more position and activity specific movements (e.g., resistance bands) in the general baseball population. The results, however, are encouraging, with potentially the most interesting results being the increases in both IR and ER, since most previous interventions have documented an indirect correlation between IR and ER changes with some eliciting no change.^3,21,32 Currently, it is not known how this simultaneous increase affects throwing velocity, injury rates overtime, and the retention of ROM increases. Future study of TMR® should assess its effect across multiple variables (e.g., ROM increase retention, injury rates, throwing velocity).

CONCLUSION

In this study, Total Motion Release® appeared to be an effective, hands‐free intervention for improving dominant shoulder ROM in the overhead throwing athlete when compared to a traditional warm‐up protocol. The simplicity of the two Total Motion Release® movements utilized during this study made it easy for the participants to identify the “good” side during the TT and AR motions. The TMR® interventions do not require large amounts of space, can be performed anywhere, are not dependent upon another individual to perform the therapy (apply a stretch), and often require less time than traditional warm‐up/stretching protocols. While the participants experienced statistically significant changes for IR and ER ROM that far exceeded the published expectations for improving shoulder ROM after utilizing TMR®, further research is needed to determine the duration of effect of a TMR® warm‐up such as was utilized in this research.