Shoulder joint mobilization does not acutely affect strength or proprioception in healthy individuals

Abstract

Shoulder joint mobilization is frequently used in physiotherapy to enhance joint function and neuromuscular control. However, its acute effects on muscle strength and proprioception remain unclear. This study aimed to investigate whether a single session of shoulder mobilization would acutely enhance shoulder strength and proprioception compared with a sham intervention. Forty-eight healthy university students (aged 18–25) were randomly assigned to either a mobilization group (n = 24) or a sham group (n = 24). The intervention group received passive glenohumeral joint mobilization (inferior, anterior, and posterior glides), while the sham group received simulated mobilization without mechanical input. Isometric shoulder muscle strength (flexion, abduction, internal/external rotation) was measured using a handheld dynamometer, and proprioception was assessed via a laser-assisted joint position reproduction (JPR) test. Baseline and immediate post-intervention assessments were conducted. Data were analyzed using linear mixed-effects models. No significant group × time interaction effects were found for any strength or proprioception outcome (all p > 0.05). A non-significant trend toward improvement in shoulder proprioception over time was observed in both groups (p = 0.103), but this was not specific to the mobilization intervention. No statistically significant main effects of group or time were detected for any muscle strength measures. A single session of shoulder joint mobilization did not produce statistically significant changes in muscle strength or proprioception in healthy individuals. These results indicate that immediate neuromuscular responses to mobilization are limited. Therapeutic benefits may require repeated applications or may be more evident in symptomatic individuals. ClinicalTrials.gov Identifier: NCT06910332. Registered on 28 March 2025. Last updated 11 September 2025. Ethics approval: Acıbadem University and Acıbadem Healthcare Institutions Medical Research Ethics Committee (ATADEK, approval no. 2025-04/185).

Introduction

The shoulder joint, with its wide range of motion (ROM) and functional complexity, is essential for daily activity but prone to instability. Due to its anatomical design, it is inherently less stable than other joints, which increases its vulnerability to various musculoskeletal disorders. Such conditions often manifest as pain, reduced ROM, and functional limitations, affecting both daily activities and athletic performance. In clinical practice, shoulder rehabilitation often incorporates electrotherapeutic modalities, therapeutic exercises, and manual therapy techniques. Among these, joint mobilization is frequently employed as a passive intervention aimed at alleviating pain and improving joint mechanics and neuromuscular control^1,2.

Although joint mobilization is widely used to restore mobility and alleviate discomfort, its specific effects on proprioception and muscle strength remain unclear. Proprioception—the body’s ability to detect joint position and movement—is a critical component of motor control and joint stabilization. Adequate muscle strength is similarly essential for generating force, maintaining dynamic stability, and ensuring efficient performance during upper extremity movements. It has been proposed that manual therapy techniques may influence the somatosensory system by stimulating joint mechanoreceptors and modulating afferent feedback pathways. Recent mechanistic models further suggest that these effects may not be solely biomechanical, but may also involve peripheral, spinal, and supraspinal modulation, influencing nociceptive processing and motor output³. Through this mechanism, such interventions may indirectly enhance motor performance and muscle strength via neuromuscular facilitation⁴.

Several studies have demonstrated the benefits of mobilization within longer rehabilitation programs (e.g., 2–6 weeks)⁵, evidence regarding its immediate or acute effects on proprioception and muscle strength—particularly in the shoulder joint—remains limited. Findings from studies on other joints have been inconsistent. For instance, Mulligan mobilization improved proprioception in knee osteoarthritis⁶, whereas no immediate proprioceptive benefits were observed following similar mobilization techniques applied to the elbow in healthy individuals⁷. Likewise, Acet et al.⁸ reported improvements in balance and mobility following cervical mobilization in patients with neck pain, with partial effects on proprioception. These inconsistencies likely stem from differences in mobilization techniques, participant characteristics, and proprioception assessment protocols. Notably, only a very small number of studies have examined acute responses in healthy individuals, and none have used a sham-controlled design specifically for the shoulder.

In most studies to date, joint mobilization has been investigated as part of broader, long-term rehabilitation programs that include multiple concurrent interventions such as exercise therapy, electrotherapy, or patient education. While improvements in proprioception and muscle strength have been observed in these multi-modal approaches, it remains unclear to what extent such gains can be attributed specifically to the mobilization component. This methodological limitation complicates interpretation and hinders the development of targeted, evidence-based interventions. Additionally, because most existing studies have been conducted in symptomatic populations, it remains unclear whether the reported neuromuscular changes are driven by modulation processes associated with pain reduction—such as decreased muscle inhibition, altered sensory processing, or central neural responses—or whether mobilization may also elicit neurophysiological effects through alternative mechanisms. To address this gap, the present study evaluated the acute effects of a single session of shoulder joint mobilization in healthy individuals, aiming to isolate its specific contribution to neuromuscular function. Accordingly, we hypothesized that a single session of shoulder mobilization may or may not acutely alter proprioception or strength compared with a sham intervention.

Methods

Study design

This study was designed as a randomized, double-blind, sham-controlled trial to investigate the acute effects of shoulder joint mobilization on muscle strength and proprioception, and no patients or members of the public were involved in the design, conduct, or reporting of the trial. The trial was conducted and reported in accordance with the CONSORT 2010 guidelines (updated 2025 extension) for randomized controlled trials⁹. The study protocol was approved by the Acıbadem University and Acıbadem Healthcare Institutions Medical Research Ethics Committee (ATADEK; approval no. 2025-04/185), and all participants provided written informed consent prior to data collection. The study was registered at ClinicalTrials.gov (NCT06910332). No changes to the study methods or outcome measures were made after trial commencement. The flow of participants through each stage of the trial is presented in Fig. 1.

Fig. 1.

CONSORT 2025 flow diagram. Flow diagram of the progress through the phases of a randomised trial of two groups (that is, enrolment, intervention allocation, follow-up, and data analysis).

Participants

A total of 48 healthy university students aged between 18 and 25 years voluntarily participated in the study. Inclusion criteria were: no shoulder pain or injury within the past 6 months, no history of musculoskeletal or neurological pathology affecting the shoulder, and no previous shoulder surgery. Individuals with prior knowledge or training in joint mobilization techniques were excluded to ensure the integrity of the blinding process.

Recruiting symptom-free individuals provided a controlled model to explore whether mobilization alone can influence proprioception and muscle strength without the influence of clinical symptoms, pain-modulation effects, or arthrogenic muscle inhibition.

Sample size was calculated using the G*Power 3.1 software (Heinrich Heine University Düsseldorf). The calculation was performed using a two-tailed t-test for differences between two independent means, with an effect size of 0.803 derived from a previous study that examined the effects of Maitland mobilization on proprioception¹⁰, a power (1–β) of 0.80, and a Type I error probability (α) of 0.05. The required sample sizes were determined to be 20 and 22 per group. Considering the possibility of participant withdrawal, the final sample size was set at 24 individuals per group, yielding a total of 48 participants included in the study.

Randomization and blinding

Participants were randomly assigned to one of two groups in a 1:1 ratio using simple randomization. A random sequence was generated using the RAND function in Microsoft Excel by an independent researcher not involved in the assessment or intervention. Group allocations were then placed in sealed, opaque, sequentially numbered envelopes to ensure allocation concealment. The two study groups were as follows:

• Mobilization Group (n = 24): Received true shoulder joint mobilization.

• Sham Group (n = 24): Received a placebo treatment mimicking mobilization without applying mechanical glide or joint distraction.

Interventions

The interventions were delivered by third-year physiotherapy undergraduate student who had completed his manual therapy coursework. Prior to data collection, they received standardized training from a physiotherapist with 10 years of clinical experience, who also confirmed proper technique and adherence to the intervention protocol.

Mobilization group.

Participants assigned to the mobilization group received passive glenohumeral joint mobilization applied to their dominant shoulder. Arm dominance was defined as the preferred arm used for writing. During the intervention, the participant was positioned supine with the shoulder in a resting position (approximately 30° abduction and slight flexion). The therapist stood on the ipsilateral side of the treated shoulder, with one hand placed over the humeral head for stabilization and the other grasping the proximal humerus to direct the glide.

Three mobilization directions—inferior, anterior, and posterior glides—were applied using a Maitland grade III technique, characterized by large-amplitude rhythmic oscillations performed into tissue resistance at a frequency of approximately 1 Hz. This rhythm was practiced during the initial training to promote consistent application across participants. Each direction was applied for 1 min, followed by a 30-s rest interval, resulting in a total mobilization duration of approximately 4.5 min Fig. 2A. The selected dosage reflects commonly applied clinical practice parameters; however, it does not represent a confirmed optimal dose, as standardized evidence-based dosing recommendations for joint mobilization are currently lacking¹¹.

Fig. 2.

Assessment and intervention procedures used in the study

Sham group.

Participants in the sham group received a single session of simulated mobilization. The therapist maintained hand contact on the participant’s shoulder in the same anatomical positions as in the mobilization group but did not apply any joint glide or traction. The hand positions and duration of contact mimicked the mobilization protocol, including 1-min intervals and 30-s rests between the sham glide directions. This procedure was intended to replicate the sensory and procedural elements of manual therapy without delivering mechanical input to the joint.

Outcome measures

Muscle strength assessment.

Isometric muscle strength of the shoulder—specifically the abductors, flexors, internal rotators, and external rotators—was assessed using a handheld dynamometer (Lafayette Hand-Held Dynamometer, Model 01165 A, Lafayette, IN, USA). Strength testing was performed using a standardized make-test procedure, in which participants gradually exerted force against the dynamometer while the examiner provided stable manual resistance. Shoulder flexors were tested at 90° shoulder flexion with the elbow extended; abductors at 90° shoulder abduction with the elbow extended; and internal/external rotators with the arm at the side and the elbow flexed to 90°. The dynamometer was positioned proximal to the elbow for flexion and abduction, and proximal to the wrist for rotation tests^12,13. Three trials were performed for each muscle group with 30-s rest intervals, and the mean value was recorded in kilograms Fig. 2B. The reliability and validity of hand-held dynamometry for shoulder isometric strength assessment have been well established, with evidence supporting high test–retest reliability and strong concurrent validity in healthy individuals^14,15.

Proprioception assessment.

Shoulder joint proprioception was evaluated using a laser-pointer-assisted Joint Position Reproduction (JPR) test. A laser pointer was attached 5 cm proximal to the lateral epicondyle of the dominant arm. Participants actively raised their arm to the target position (90° flexion or 90° abduction), closed their eyes, and held the position for 5 s, then returned the arm to the starting position. They were subsequently instructed to reproduce the same position. One practice trial was provided before testing. The laser point was projected onto a sheet with 5-cm reference lines, and reproduction error was measured in millimeters using a standard ruler Fig. 2C. This laser-assisted JPR method has previously demonstrated good to excellent reliability for shoulder position sense assessment in healthy individuals, with reported intrarater and interrater intraclass correlation coefficients of 0.78 and 0.86, respectively¹⁶. Because the measurement was performed manually, no device calibration or angular-to-linear conversion was required. A greater JPR error indicates poorer joint position sense, reflecting reduced proprioception of the shoulder^16,17.

Data collection procedure

All participants first underwent baseline assessments, followed by the assigned intervention (mobilization or sham), and then immediate post-intervention assessments. Participants were recruited and data were collected between April and May 2025. All procedures were conducted in the Physiotherapy and Rehabilitation Practice Laboratory at Acıbadem Mehmet Ali Aydınlar University, Istanbul, Turkey, to ensure consistent environmental conditions across all sessions.

To maintain the integrity of the study’s double-blind design, participants were unaware of their group allocation, and all outcome assessments were performed by a blinded evaluator who was not involved in the intervention process. To minimize the effects of fatigue, brief rest periods were provided between repeated trials during strength and proprioception testing.

Statistical analysis

Prior to the main analyses, the assumption of normality for all outcome variables was assessed using visual inspection (histograms and Q-Q plots) and the Shapiro-Wilk test. For baseline comparisons between groups, independent samples t-tests were used if the data were normally distributed, and Mann-Whitney U tests were applied otherwise. Subsequently, data were analyzed using linear mixed-effects models. Group (Mobilization vs. Sham) and Time (Pre vs. Post) were entered as fixed effects, and subjects were included as a random effect to account for repeated measures. Values exceeding ± 3.0 SD were treated as measurement-level outliers and excluded according to a predefined rule. For all linear mixed-effects models, the Time effect was parameterized as the contrast Pre–Post; therefore, positive estimates indicate lower post-intervention values, whereas negative estimates indicate greater post-intervention values. The main effects and the group × time interaction were evaluated for each outcome (muscle strength and proprioception). A p-value < 0.05 was considered statistically significant. All analyses were conducted using Jamovi software (v.2.4) with the GAMLj3 module¹⁸. No single primary outcome was prespecified; therefore, all analyses were conducted as planned exploratory analyses, and no familywise error-rate correction was applied. Effect sizes for fixed effects and interaction terms were quantified using partial eta squared (ηp²). Effect size magnitudes were interpreted according to established benchmarks for analysis of variance, with values < 0.06 considered small, values between 0.06 and 0.14 considered medium, and values > 0.14 considered large effects¹⁹. These thresholds were used to aid interpretation of the practical relevance of statistically non-significant as well as significant findings.

Results

During preliminary data screening, three extreme values exceeding ± 3.0 SD were identified and excluded from the statistical models to minimize the influence of outliers. These exclusions applied only to individual measurements, not to participants, and thus all 48 randomized individuals completed the interventions and were retained in the per-protocol analysis. No adverse events were observed or reported in either group during or immediately after the intervention.

Demographic characteristics, including age, gender, and hand dominance, were compared to ensure baseline homogeneity between groups. Mean age was similar between the mobilization and sham groups (21.1 ± 1.6 vs. 20.9 ± 1.7 years; U = 277.5, p = 0.826). Gender distribution was comparable (mobilization: 14 women/10 men; sham: 13 women/11 men; p = 1.000, Fisher’s exact test), as was hand dominance (mobilization: right/left = 23/1; sham: 21/3; p = 0.609, Fisher’s exact test), confirming that the groups were well matched at study entry.

Prior to the intervention, baseline differences between the mobilization and sham groups were assessed using the Mann-Whitney U test. The results indicated no statistically significant differences between groups in any of the outcome variables at baseline. Muscle strength values at baseline did not differ significantly between the mobilization and sham groups in shoulder flexion (U = 284.0, p = 0.934), abduction (U = 277.0, p = 0.821), external rotation (U = 276.0, p = 1.000), or internal rotation (U = 270.0, p = 0.898). Similarly, proprioception values showed no significant difference between groups in both shoulder flexion (U = 222.0, p = 0.250) and abduction (U = 252.0, p = 0.491) (Table 1).

Table 1.

Baseline comparison of outcome measures between the mobilization and Sham groups.

Variable		Group	N	Outlier	Min	Q1	Median	Q3	Max	U	p
Muscle strength	Flexion	Mobilization	24	0	9.2	13.5	17.3	26.6	36.9	284	0.934
		Sham	24	0	10.9	13.1	19.5	27.3	43.6
	Abduction	Mobilization	24	0	9.37	14.4	17.6	24.7	40.7	277	0.821
		Sham	24	0	10.7	13.4	17.8	25.6	37.2
	External rotation	Mobilization	24	0	5.43	8.27	9.82	13.1	19.4	276	1
		Sham	23	1	5.9	8.18	9.4	14.7	19.8
	Internal rotation	Mobilization	24	0	7.47	11.3	15.4	19.5	27	270	0.898
		Sham	23	1	8.63	9.8	14.6	19.7	28.4
Proprioception	Flexion	Mobilization	23	1	31.3	45.3	54	68.3	121	222	0.25
		Sham	24	0	30	48.3	62.8	80.1	113
	Abduction	Mobilization	24	0	41.3	68.8	86.7	111	151	254	0.49
		Sham	24	0	35.3	64.8	85.3	98.3	163

Linear mixed model analysis revealed no significant interaction effects between group and time for any of the outcome variables, indicating that the changes observed over time were not different between the mobilization and sham groups. Specifically, the interaction effect was non-significant for flexion strength (F(1,46) = 1.795, p = 0.187), abduction strength (F(1,46) = 1.046, p = 0.312), external rotation strength (F(1,44.7) = 1.253, p = 0.269), and internal rot ation strength (F(1,44.8) = 0.199, p = 0.658). In proprioceptive outcomes, interaction effects were again non-significant for flexion (F(1,46) = 1.577, p = 0.215) and abduction (F(1,46) = 0.016, p = 0.901). Across all outcomes, group × time interactions were associated with small or negligible effect sizes (partial η² = 0.0003–0.038), indicating the absence of a clinically meaningful acute effect (Table 2).

Table 2.

Results of linear mixed model analysis for muscle strength and proprioception outcomes.

Variable		Effect	Estimate	SE	CI lower	CI upper	F	p	partial η²
Muscle strength	Flexion	Group	0.9	2.451	−3.97	5.77	0.135	0.715
		Time	−0.421	0.318	−1.053	0.211	1.749	0.193
		Group × Time	0.853	0.637	−0.412	2.117	1.795	0.187	0.038
	Abduction	Group	0.35	2.157	−3.934	4.634	0.0263	0.872
		Time	0.314	0.288	−0.258	0.886	1.189	0.281
		Group × Time	−0.589	0.576	−1.733	0.555	1.0462	0.312	0.022
	External rotation	Group	0.9631	1.16	−1.342	3.268	0.6891	0.411
		Time	0.0158	0.209	−0.4	0.432	0.0057	0.94
		Group × Time	−0.4683	0.418	−1.3	0.363	1.2528	0.269	0.027
	Internal rotation	Group	0.167	1.746	−3.302	3.637	0.0092	0.924
		Time	−0.17	0.316	−0.798	0.458	0.2899	0.593
		Group × Time	0.282	0.632	−0.974	1.538	0.1989	0.658	0.004
Proprioception	Flexion	Group	1.58	4.77	−7.9	11.1	0.11	0.742
		Time	6.86	4.12	−1.33	15.1	2.767	0.103
		Group × Time	10.36	8.25	−6.03	26.8	1.577	0.215	0.033
	Abduction	Group	−5.68	7.04	−19.66	8.3	0.6518	0.424
		Time	4.74	5.11	−5.42	14.89	0.8587	0.359
		Group × Time	−1.28	10.22	−21.58	19.03	0.0156	0.901	0.0003

Partial eta squared (η²p) values were calculated from the F statistics using the formula η²p = F × df_effect / [(F × df_effect ) + df_error].

Furthermore, no significant main effects of group or time were detected in any variable. However, a trend toward improvement over time was noted in proprioception measured during flexion, with a near-significant main effect of time (F(1,46.0) = 2.767, p = 0.103). This suggests a possible general improvement in proprioceptive acuity regardless of intervention type, though it did not reach statistical significance.

Discussion

This randomized, double-blind, sham-controlled study investigated the acute effects of shoulder joint mobilization on muscle strength and proprioception in healthy individuals. The findings showed no statistically significant differences between the mobilization and sham groups in any outcome following the intervention. Additionally, no significant group × time interaction was observed in any parameter, suggesting that the changes seen over time were not specific to the mobilization treatment.

This study showed that a single session of shoulder mobilization did not significantly affect shoulder strength or proprioception in healthy individuals. In the literature, findings regarding the acute effects of joint mobilization on muscle strength following a single application are mixed for both symptomatic and asymptomatic populations. Among symptomatic individuals, Alkhawajah and Alshami (2019) observed significant improvements in knee muscle strength in patients with osteoarthritis immediately after mobilization with movement⁴, and Pfluegler et al. (2021) demonstrated acute strength enhancements following a single session of passive hip mobilization in individuals with anterior knee pain and impaired hip function, suggesting that joint mobilization may be more effective when baseline deficits are present²⁰. In contrast, two studies specifically targeting the shoulder joint—Guimarães et al. (2016) in patients with impingement syndrome and Lluch et al. (2018) in overhead athletes with chronic shoulder pain—did not report any significant improvements in shoulder muscle strength following a single session of mobilization^21,22.

Among asymptomatic individuals, Ersoy et al. (2019) reported a significant increase in ankle dorsiflexor strength following a single session of Maitland grade III mobilization, compared to grade I mobilization²³. Conversely, Tomruk et al. (2020) found no such effect after ankle joint mobilization with movement in healthy participants²⁴. These discrepancies may be attributed to variations in intervention parameters such as mobilization duration (e.g., 180 s in Ersoy et al. vs. 10 repetitions in Tomruk et al.), the type and intensity of mobilization technique (e.g., Maitland grade III vs. mobilization with movement), and the nature of placebo control employed in each study. Supporting this variability, a systematic review by Pfluegler et al. (2020) concluded that there is low-quality evidence supporting strength gains in asymptomatic individuals, and very low-quality evidence suggesting no such improvement in symptomatic populations²⁵. Collectively, these findings suggest that the neuromuscular response to joint mobilization is likely context-dependent and may not uniformly enhance muscle strength across different joints or populations. Moreover, the lack of consistent strength improvements, particularly in asymptomatic individuals, challenges the notion that joint mobilization facilitates muscle performance primarily by alleviating pain-mediated inhibition.

Several studies have investigated the effects of joint mobilization on position sense in symptomatic populations using multi-session protocols. Erol et al. (2025) reported significant improvements in proprioception following a two-week Mulligan mobilization with movement (MWM) program in individuals with chronic non-specific low back pain²⁶. Similarly, Acet et al. (2024) found that a three-week cervical mobilization protocol led to significant improvements in joint position sense, particularly in left cervical rotation, among patients with nonspecific neck pain⁸. In neurologically impaired individuals, Maden et al. (2024) showed that adding cervical mobilization to traditional rehabilitation over four weeks enhanced knee position sense and balance in patients with multiple sclerosis, indicating possible remote effects of spinal mobilization²⁷. Agyenkwa et al. (2025) reported improved joint position sense following a 4-week intervention involving either self-administered cervical SNAGs or kinesiology taping in individuals with nonspecific neck pain associated with prolonged electronic device use²⁸. However, not all multi-session studies have shown favorable results. Sezerel and Yüksel (2024) found no improvement in cervical position sense after four weeks of mobilization in patients with cervical spondylosis, while improvements were seen only in those receiving muscle energy techniques²⁹. Zanjani et al. (2024) reported no additional benefit of Mulligan mobilization over scapular-focused exercise in improving proprioception in female athletes with shoulder impingement³⁰. Celik and Menek (2025) observed no proprioceptive improvement following three weeks of Maitland or Mulligan mobilization in individuals with rotator cuff lesions, despite improvements in other clinical parameters³¹. However, in a similar population, Menek and Menek (2025) found that Mulligan mobilization was more effective than corticosteroid injection in improving shoulder joint position sense, with both interventions combined with conventional therapy³².

In contrast, single-session studies conducted in asymptomatic individuals generally report limited or no improvements in joint position sense. McNair et al. (2007) observed no change in cervical position sense following a single mobilization session in a patient with acute neck pain, despite gains in ROM³³. Similarly, Kaçmaz and Ünver (2023) found no meaningful change in elbow position sense after Mulligan mobilization in healthy participants, attributing this to the absence of baseline deficits and possible sensory input from the sham condition⁷. Gong (2013, 2014) reported significant improvements in cervical and lumbar joint position sense following mobilization plus massage in healthy adults, but limitations such as small sample sizes and lack of blinding reduce the reliability of these findings^34,35.

The present study, which examined the immediate effects of a single session of shoulder joint mobilization in healthy individuals, aligns with prior findings in asymptomatic populations, showing no statistically significant change in joint position sense. Nonetheless, a small, non-significant change over time was noted. However, it is unclear whether these small, imprecise changes reflect true neurosensory modulation or a learning effect from repeated testing. These findings support the notion that the proprioceptive effects of joint mobilization are more likely to emerge in symptomatic individuals and through repeated applications, particularly when baseline sensorimotor impairment or pain-related inhibition is present. The shoulder relies predominantly on active neuromuscular control and sensorimotor integration rather than passive structural stability. Given the high degrees of freedom of the glenohumeral joint and the distributed contribution of capsuloligamentous and musculotendinous mechanoreceptors, a single, brief mobilization session may be insufficient to generate the level of afferent input required to induce measurable immediate changes in shoulder proprioceptive control³⁶.

To our knowledge, this is the first study to assess these effects in the shoulder using a sham-controlled design, which allows for a more accurate interpretation of the intervention’s specific contribution, independent of non-specific or placebo-related influences. Future research should investigate repeated mobilization sessions in clinical populations with proprioceptive deficits to determine potential therapeutic benefits.

Strengths and limitations

This study’s strengths include its randomized, double-blind, sham-controlled design, which minimized bias and allowed for the specific effects of mobilization to be isolated using a well-matched sham control. Evaluating the acute effects of a single session addressed a gap in the manual therapy literature, and the use of objective, standardized measures enhanced the reliability of findings.

However, the sample was limited to young, healthy individuals, restricting generalizability to clinical populations. Although participant blinding was maintained, complete sensory equivalence between sham and mobilization conditions cannot be fully ensured and no formal blinding integrity assessment (e.g., participant or assessor guess test) was conducted. Additionally, although the study aimed to reflect the typical time and positioning used in clinical practice, the brief duration of the intervention (~ 4.5 min) may have been insufficient to elicit measurable neuromuscular effects. This aligns with the evidence indicating substantial variability and a lack of consensus regarding optimal mobilization dosage in the literature.

The sensitivity of the outcome measures may also have limited the detection of subtle sensorimotor or strength-related changes. Although handheld dynamometry and laser-assisted joint position reproduction testing have established clinical utility, more sensitive laboratory-based tools (e.g., isokinetic dynamometry, EMG, or motion capture) may better capture small neuromuscular adaptations. Furthermore, because the participants were healthy individuals with intact baseline performance, potential ceiling effects may have further restricted the ability to detect small acute changes.

Conclusion

In this study, a single session of shoulder joint mobilization did not significantly change muscle strength or proprioception in healthy individuals. While a minor trend toward improved proprioceptive performance was observed over time, this effect was not statistically significant and was not specific to the mobilization group. These findings suggest that acute neuromuscular responses to mobilization may be minimal or difficult to detect in asymptomatic populations, and that therapeutic benefits of mobilization may require repeated sessions or may be more evident in patients with sensorimotor deficits.

Implications for physiotherapy practice

The absence of immediate neuromuscular effects in healthy individuals suggests that a single session of joint mobilization should not be expected to produce acute improvements in muscle strength or proprioception in asymptomatic populations. These findings indicate that mobilization-related neuromuscular mechanisms may be more strongly engaged in the presence of pain, sensorimotor impairment, or reduced baseline function—such as through pain reduction, decreased protective motor inhibition, and subsequent normalization of sensorimotor processing—pathways that are less likely to be activated in healthy individuals with intact baseline function.

Author contributions

AÖA: Conceptualization, Methodology, Investigation, Data Analysis, Project Administration, Writing—Original Draft, Writing—Review & Editing. AA, KE, SI, RB: Methodology, Data Collection, Writing—Review & Editing. All authors read and approved the final version of the manuscript.

Funding

This study received no external funding.

Data availability

The datasets generated and analyzed during the current study are available from the corresponding author upon reasonable request.

Declarations

Ethics approval and consent to participate

The study protocol was approved by the Acıbadem University and Acıbadem Healthcare Institutions Medical Research Ethics Committee (ATADEK) with the approval number 2025-04/185. All participants provided written informed consent prior to participation, in accordance with the Declaration of Helsinki.

Consent for publication

Not applicable.

Competing interests

The authors declare that they have no competing interests.

Use of artificial intelligence

Artificial intelligence tools (ChatGPT, OpenAI, 2024) were used to assist in language refinement, grammar correction, and formatting during the manuscript preparation process. No AI-generated content was used for data analysis, interpretation, or original scientific writing. All content was reviewed and approved by the authors.