Sensorimotor and proprioceptive exercise programs to improve balance in older a systematic review with meta-analysis

Authors: Silvo Pšeničnik Sluga, Žiga Kozinc

Abstract

The primary aim of this study was to systematically review and meta-analyze the impact of sensorimotor and proprioceptive exercises on balance in older adults. We also sought to define how researchers describe proprioceptive and sensory-motor training and their respective protocols. The review was conducted following the PRISMA guidelines, with searches performed in March 2023. Both authors carried out independent searches using the PubMed and PEDro databases. From a total of 320 identified records, 12 studies were deemed eligible for meta-analysis after screening and removal of duplicates. The average PEDro score was 5.11±1.11 indicating overall fair quality of studies. Common outcome measures included the Berg balance scale, Timed up and go test, Tinetti balance scale, Functional reach test and various single-leg stance tests. All outcomes were significantly improved by the interventions (standard mean difference = 0.65 – 1.29), with little difference between proprioceptive and sensorimotor training. However, the quality of evidence ranged from “very low” to “low” based on GRADE guidelines, suggesting further high-quality studies are needed. This review underscores the potential benefits of sensorimotor and proprioceptive exercises for enhancing balance in older adults, while also highlighting the ambiguity and inconsistency regarding the usage of the terms proprioceptive and sensorimotor training.

Ethical Publication Statement

We confirm that we have read the Journal’s position on issues involved in ethical publication and affirm that this report is consistent with those guidelines.

Older adults are growing in number, resulting in higher prevalence of musculoskeletal injuries. Age-associated functional declines in muscle strength and the sensory systems, along with other changes, contribute to reductions in balance and a consequent increase in fall risk.^1^ A systematic literature review demonstrated that an increased risk of falls is associated with history of falls, being unstable while walking, cognitive disturbances, physical inactivity, antidepressant use, confusion, and urinary incontinence.^2^ Vieira et al.^3^ listed outside obstacles, vertigo, sleep disturbance, chronic illness, several medications, and need for personal assistance as risk factors for geriatric patient falls. Fall related injuries have medical, psychological and social implications and are associated with high medical costs. A need for prolonged treatment along with associated psychological and physical limitations may lead to loss of independence in activities of daily living.^4,5^ Falls and associated injuries are common in older adults, with approximately 30% of adults 60 years of age or older experiencing a fall over a one-year period.^5,6^ Falls are more common in elderly individuals who are physically weaker and those living in senior housing/facilities. Falls lead to soft-tissue injuries, bone fractures, subsequent difficulties with activities of daily living, and depression.^7^

Fall prevention strategies play an important role in reducing falls and their associated comorbidities.^8^ Several studies have shown that exercise interventions including balance exercises and walking training are effective in mitigating the risk of falls.^9^ Proprioceptive and sensory-motor training are two promising interventions for fall prevention and balance improvement.^10^ Components of proprioceptive system are a foundational element of movement and play a key role in motor behavior.^11^ Maintaining balance relies on efficient integration of sensory information from visual, vestibular and somatosensory systems.^12,13^ During locomotion, sensory neurons provide important information about limb location and movement in space.^14^ Elderly subjects are more dependent on visual information to ensure balance control, which is reflected in a more pronounced deterioration of balance when vision is removed.^15^ Proprioceptive functions degenerate with age, which has been linked to balance deficits and increased risk of falling.^16^ Proprioceptive training is an intervention aimed at improving proprioceptive function. It focuses on the use of proprioceptive signals, including kinesthetic and tactile-afferent senses, in the absence of information such as visual perception. The end-goal of such training is improvement and recovery of sensorimotor function.^17^ Many studies also incorporate walking on uneven surfaces into proprioceptive training of lower limbs, which contributes to generation of movement responses and joint stability.^10^

Sensorimotor training is a similar approach, which by definition includes an accelerated input of somatosensory and proprioceptive stimuli, correcting muscle imbalance and ensuring a correct motor program at the central nervous system level.^18^ The central nervous system integrates sensory and motor information to acquire skilled movements and respond to external perturbations through a process known as sensory-motor integration. The reciprocal interaction of the sensory and motor systems is a prerequisite for learning and performing skilled movement.^19^ Simultaneous activity of both systems stimulates plasticity at their junction and is used to improve sensory and motor inputs in the sensorimotor integration centers. This is the process by which one senses one’s own body and the surrounding environment in order to preform movement.^19^ Researchers are finding that training interventions focusing on the execution of correct, rapid and well-directed steps may have a very valuable role in preventing falls. Training is particularly appropriate on uneven surfaces because it improves individual’s cognitive perception and sensorimotor abilities.^20^

The primary aim of this paper was to conduct a systematic literature review and meta-analysis to determine the distinct effects of sensorimotor and proprioceptive exercise on balance in older adults. Unlike previous reviews, our work specifically compares these two types of exercises, addressing a gap in the literature. This paper stands out in its effort to clarify the overlapping and often ambiguous definitions of proprioceptive and sensorimotor training. Due to the ambiguous and versatile definitions of these terms across studies, a question arises whether they are truly two different approaches or simply two different terms describing the same approach.^21^ Aman et al.^17^ found that many studies use the term proprioception very loosely, frequently relying on tasks that include multimodal sensorimotor learning. Our analysis directly addresses this concern by critically examining the definitions and implementations in the included studies. We argue that distinguishing between sensorimotor and proprioceptive exercises is essential for scientific accuracy and clinical application. If we adopt the stance that any form of sensorimotor learning denotes proprioceptive exercise, the term itself carries little scientific meaning for the clinical community. If sensorimotor training is a form of unimodal sensory training or a form of specialized sensorimotor learning, this should be explicitly stated in order to avoid terminological unclarity and confusion.^21,22^ Despite a large number of published studies about proprioceptive and sensorimotor exercises, there is a general lack of consensus on the exact meaning of these two terms, with different exercises being included in the training regimens. Consequently, the impact of proprioceptive and sensorimotor interventions on balance in elderly adults is unclear. Through our systematic approach, we provide insights into the distinct effects of these interventions, thereby contributing significantly to the field.

Materials and Methods

Search Strategy and inclusion criteria

The review was conducted according to PRISMA guidelines. The review was not prospectively registered, as the PROSPERO database only accepted COVID-19- related protocols at the time this review was initiated. The search was performed in March 2023. Both authors independently performed all search steps, and any disagreements were resolved by discussion. We searched the PubMed, Google Scholar and PEDro database. For PubMed, we used the following search (proprioceptive training OR proprioception training OR proprioception exercise OR sensorimotor training) AND (older adults OR eldery OR ageing). In the PEDro database, we used the simple search option and separately entered four individual combinations of words (i.e., “sensorimotor training elderly”, “sensorimotor training older adults”, “proprioception training elderly” and “proprioception training older adults” were used). In Google Scholar database, we used the simple search option and separately entered two individual combinations of words (i.e., “older adults proprioception training” and “older adults sensorimotor training” were used). In addition, we reviewed the reference lists of identified systematic reviews on the topic, and scrutinized reference lists of articles included in the first phase. The records were imported into Mendeley (version 1.19.8) to remove the duplicates, and then exported into Microsoft Excel software for further examination.

The inclusion criteria, structured according to the PICOS tool,^23^ were determined as

• P (population): Participants aged 55 years or more. Although older adults are typically classified as older than 65 years, balance deterioration may begin as early as after age 50. ^4,25^ Therefore, we decided to decrease the minimum participant age for 10 years. Studies were included if the participants were healthy or had chronic non-communicable diseases, with subgroup analysis attempts made where possible.
• I (Intervention): Exercise-based intervention, denominated as “sensorimotor” or “proprioceptive” training.
• C (Comparison): Control groups receiving no intervention, “usual care” intervention or educationbased intervention.
• O (Outcome): Instrumented or field-based balance tests (posturography, single-leg stance test) or balance scales (e.g., Berg balance scale, Tinneti balance scale)
• S (Study design): Randomized and non-randomized controlled trials.

Data extraction

The data extraction was performed by both authors and disagreements were resolved through additional discussion. The following data was (a) baseline, post-intervention and follow-up data (means and standard deviations) for all outcome measures for experimental and control groups; changes (in %) were considered instead of pre-post data when available (b) baseline demographics of participants (sex, age, body height, body mass, body mass index); (c) intervention characteristics (duration of the intervention, weekly frequency, volume (number of exercises, sets, and repetitions), inclusion if resistance exercise, breaks, and supervision). Data were carefully collected into Microsoft Excel 2016 (Microsoft, Redmond, WA, USA). If the data were presented in a graphical format, we used GetGraphDataDigitalizer software (version 2.26.0.20) to accurately determined the means and standard deviations. In case of missing data, the authors of the articles were contacted by e-mail A reminder was sent after 14 days, and if no reply was received, the data was considered irretrievable.

Study quality assessment

Both authors evaluated the risk of bias of the included studies using the PEDro scale which assesses study quality based on a 10 items.^26^ Potential disagreements between the reviewers were resolved by discussion. Studies scoring from 9 to 10 were considered as “excellent,” 6 to 8 as “good,” 4 to 5 as “fair,” and <4 as “poor” quality. The PEDro scale was selected because it was specifically developed to evaluate the quality of clinical trial studies investigating physical therapy interventions.^27^

Certainty of evidence assessment

The certainty of evidence was assessed according to GRADE guidelines.^28^ GRADE guidelines encompass 5 main domains (risk of bias, precision, consistency, directness, and publication bias) to categorize evidence quality. The comparisons were classified as representing either high, moderate, low or very low quality of evidence. Each study score started as “high quality”, and the level of evidence was downgraded a) there was a substantial heterogeneity among the studies (I2 > 50 % or statistically significant heterogeneity test (inconsistency); b) more than 25 % of studies were classified as fair or poor quality (risk of bias); c) the studies assessed the effects of the intervention indirectly (e.g., population, intervention or outcome not being representative of the research question) (indirectness), d) when a large CI was observed, or when the total number of participants was <200 (imprecision) e) when the study results provided differed from the original protocol or study objectives (publication bias).^29^

Data analysis

The meta-analysis was done in Review Manager software (Version 5.3, Copenhagen: The Nordic Cochrane Center, The Cochrane Collaboration, London, UK). Although there has been consensus on the minimum number of studies required for a meta-analysis [30], we decided to performed the analyses when three or more studies could be included. Before the results were entered into the meta-analysis software, the pre-post differences were calculated by subtracting baseline values from post-intervention values. In addition, standard deviations of the pre-post difference were calculated according to the following formula SD = √[(SD2pre + SD2post) – (2 × r × SDpre × SDpost). The correction value (r), which represents the pre-test–posttest correlation of outcome measures, was conservatively set at 0.70. The meta-analyses were done using continuous outcomes module, with a random-effects model and inverse variance method. The pooled effect sizes were expressed as standardized mean difference (SMD), with 95 % confidence intervals (CI) reported alongside to provide the precision of the overall effect estimate.^31^ Absolute mean difference (MD) was also reported to provide a more tangible and practically useful estimate of the intervention effects. Statistical heterogeneity among studies was determined with the I2 statistics. According to Cochrane guidelines, the I2 statistics of 0% to 30% might not be important, 30 to 60% may represent moderate heterogeneity, 50–90% may represent substantial heterogeneity, and 75–100% indicates considerable heterogeneity. In case of substantial heterogeneity between the studies, a subgroup analysis was performed to examine the effect of moderator variables such as participants characteristics (e.g., patients vs. healthy) and intervention (e.g., sensorimotor vs. proprioceptive training, weekly frequency).

To elucidate the distinctions and similarities between proprioceptive and sensorimotor training approaches, we conducted a systematic analysis of the exercise variables employed in the included studies. This analysis encompassed the duration and frequency of the interventions, session lengths, types of exercises, implementation of gait training, the use of equipment, and the inclusion of cognitive tasks.

Results

General overview of the search results

We identified 155 records through a database search and 165 records through an additional search of the reference lists. After duplicates were removed, 135 records were screened. In a next step, 26 articles were screened for eligibility. A total of 12 studies were eligible for meta-analysis. The detailed summary of the search process is shown in Figure 1.

Detailed characteristics of included studies (participants, intervention type, control group, outcome measures, main findings) are also presented in Supplementary Materials Table 1. Both men and women participated in 10 studies, in a study by Teixeira et al.^32^ there were only women and in the study by Salah et al.^33^ had only male subjects. In most studies, the participants were adults (range of means for 60,6 to 83,2 years), except in the study by Da Silva et al.^34^ which examined older adults (57,9±8.50 years). This study was the only one where the subjects were on average younger than 60 years old. Across studies, weekly frequency ranged from 2 to 3 and session durations ranged from 30 to 60 minutes. In most studies, the control groups performed education only or usual care. In one study, the participants in the control group did perform the physiotherapy.^35^ The most common outcome measures were the Berg balance scale (9 studies), the Timed up and go test (7 studies), the Tinetti balance scale (5 studies), single-leg stance test with eyes open (4 studies), single-leg stance test with eyes closed (3 studies) and the functional reach test (2 studies). Proprioceptive training was defined in 9 studies, in 3 studies the authors defined the intervention as sensorimotor training.

Comparison between the content of proprioceptive and sensorimotor training

The detailed intervention descriptions are shown in Supplementary Materials Table 2. We observed that while the overall duration (8 to 16 weeks) and frequency (2 to 3 times weekly) of these training programs were similar. Proprioceptive training primarily included exercises aimed at enhancing the body's internal sense of position, such as balance and gait training on uneven surfaces. In contrast, sensorimotor training often incorporated a broader range of activities, integrating physical exercises with cognitive challenges to stimulate both motor and cognitive functions. A key difference was noted in the use of gait training and equipment. Gait training was more prevalent in proprioceptive exercises, whereas sensorimotor training displayed a greater diversity in equipment, including technology-enhanced tools. The inclusion of cognitive tasks was another distinguishing feature of sensorimotor training, contrasting with the predominantly physical focus of proprioceptive exercises. This analysis reveals that despite shared goals in improving balance, proprioceptive and sensorimotor training approaches exhibit distinct methodologies and emphases in their implementation, highlighting the need for clear definitions and standardized protocols in future research.

Assessment of study quality

The assessment of study quality according to Pedro Scale is shown in Supplementary Materials Table 3. Four studies were of good quality and eight studies were of fair quality. The average score was 5.11±1.11 (median = 5), indicating overall fair quality of evidence.

Effects on Berg balance scale

In total, 9 studies included BBS as an outcome measure (236 and 245 participants in experimental and control groups, respectively). There was low-quality evidence that interventions had statistically significant and large effect on BBS score (SMD = 1.29; [CI: 0.97 – 1.61]; p < 0.001; I2 = 59 %). In absolute terms, the BBS score was increased by 6.50 units [CI: 4.20 – 8.79] (Figure 2). Subgroup analyses indicted no difference (p = 0.120) in the overall effects between studies conducted with healthy participants (SMD = 1.03; [CI: 0.75 – 1.32]) and patients (SMD = 1.53; [CI: 0.97 – 2.09]). All studies but one termed their intervention as sensorimotor training, therefore, no subgroup comparison was made between proprioceptive and sensorimotor training.

Effects on Tinetti balance scale

In total, 5 studies included Tinneti balance scale as an outcome measure (132 and 140 participants in experimental and control groups, respectively). There was low-quality evidence that the interventions had statistically significant and large effect on Tinneti balance scale score (SMD = 0.83; [CI: 0.58 – 1.08]; p < 0.001; I2 = 0 %) (Figure 3). In absolute terms, the Tinneti balance scale score was increased by 2.96 units [CI: 2.14 – 3.79]. Three studies involved proprioceptive training and two used sensorimotor training. As the study effects were very homogenous (I2 = 0 %), no subgroup analyses were performed.

Effects on Timed up and Go test

In total, 9 studies included TUGT as an outcome measure (179 and 177 participants in experimental and control groups, respectively). Very low-quality evidence suggests that the interventions had statistically significant and large effect on TUGT score (SMD = 1.03; [CI: 0.59 – 1.64]; p < 0.001; I2 = 70 %). In absolute terms, the TUGT time was reduced for 2.33 seconds [CI: 1.02 – 3.64]. Four studies involved proprioceptive training and three used sensorimotor training. Subgroup analyses indicted a potential difference between the intervention types (p = 0.07), with proprioceptive training studies showing larger effect (SMD = 1.32; [CI: 0.59 – 1.91]) compared to sensorimotor training studies (SMD = 0.70; [CI: 0.37 – 1.03]). All studies but one termed their intervention as sensorimotor training, therefore, no subgroup comparison was made between proprioceptive and sensorimotor training.

Effects on single-leg stance

In total, 4 studies included single-leg stance test (eyes open) as an outcome measure (71 and 68 participants in experimental and control groups, respectively). Very low-quality evidence suggests that interventions had statistically significant and large effect on single-leg test time (SMD = 1.03; [CI: 0.58 – 1.48]; p < 0.001; I2 = 35 %) (Figure 5A). In absolute terms, the single-leg test time score was increased by 5.51 seconds [CI: 3.93 – 7.08]. Three studies involved proprioceptive training and one used sensorimotor training. Given the low number of studies and small heterogeneity between them, no subgroup analyses were performed.

In addition, three studies included single-leg test with eyes closed (50 and 47 participants in experimental and control groups, respectively). Very low-quality evidence suggests that interventions showed a moderate effect which was not statistically significant (SMD = 0.73; [CI: –0.10 – 1.48]; p < 0.090; I2 = 73 %) (Figure 5B). In absolute terms, the effect indicated an increase for 1.01 seconds [CI: –0.10 – 2.17]. Two studies involved proprioceptive training and one used sensorimotor training.

Effects on functional reach test

In addition, 2 studies included FRT as an outcome measure (31 and 28 participants in experimental and control groups, respectively). Very low-quality evidence suggests that interventions had statistically significant and moderate effect on FRT distance (SMD = 0.65; [CI: 0.12 – 1.17]; p < 0.021; I2 = 0 %) (Figure 6). In absolute terms, the FRT score was increased by 2.69 cm [CI: 0.45 – 4.92]. One study used proprioceptive training and one used sensorimotor training.

Discussion

The primary objective of this paper is to perform a systematic literature review and meta-analysis to assess the impact of sensorimotor and proprioceptive exercises on balance in older adults. Additionally, we sought to define, through qualitative analysis, how researchers describe proprioceptive and sensory-motor training and their respective protocols. We also aimed to evaluate the effectiveness of these training regimens on balance and other motor skills in older individuals via a metaanalysis. In the reviewed literature, eight studies labeled the exercise as "proprioceptive" while three termed it "sensory-motor" (refer to Supplementary Materials Table 1). Overall, older participants who underwent proprioceptive and sensorimotor training exhibited notable enhancements in most baseline measurements when compared with control groups. For most outcome measures, the evidence, albeit of very low quality, indicated that the interventions significantly improved the outcomes. Notably, the FRT outcome measure showed the interventions led to a statistically significant, moderate effect (as seen in Figure 6). Conversely, the one-leg stand test (with eyes closed) demonstrated a moderate but not statistically significant improvement due to the interventions (refer to Figure 5). One study reported no improvement in balance in the one-leg stand test (with eyes closed) following an 8-week sensorymotor training period. When considering the TUGT outcome measure, subgroup analyses revealed that studies focusing on proprioceptive exercises yielded a more pronounced effect than those involving sensorimotor exercises (see Figure 4). For the BBS outcome measure, there was no discernible difference in the overall effects between studies that focused on healthy participants versus those that focused on patients (refer to Figure 2). The findings from our literature review therefore indicate that both proprioceptive and sensory-motor training yield similar beneficial outcomes on balance in the elderly. The studies encompassed in our meta-analysis suggest that training regimens spanning 8 to 18 weeks (averaging 12 weeks), conducted 2 to 3 times weekly and lasting 30 to 60 minutes per session (with an average duration of 45 minutes), are efficacious.

Previous literature reviews complemented with metaanalyses have already explored the effects of different fall prevention programs for older adults.^36,37^ From these reviews, it is clear that balance training is recommended to decrease both the risk and incidence of falls in this age group. Despite variations in proprioceptive training protocols, the results consistently show that they are similarly effective in improving both static and dynamic balance. Balance control in individuals relies heavily on the interplay of the visual, vestibular, and proprioceptive systems. Previous studies have indicated that older individuals might experience a decline in balance control.^38^ In light of this, previous studies have designed their training to channel sensory information to the central nervous system using proprioceptive and kinesthetic inputs, particularly during specific postures and while moving dynamically. Their training approach includes exercises that are performed with both open and closed eyes. This method is believed to help focus attention on body movements and position, integrating this awareness into the central nervous system through the development of new synaptic connections.^35^ Additionally, some researchers highlight the benefits of stepping training. This training is seen as a means to help individuals make precise, rapid, and directed steps, which are essential for preventing falls. It is particularly effective in unstable conditions, as it enhances the individual's neuromuscular, psychological, and sensorymotor capabilities.^20^

Many studies have incorporated the use of an unstable surface in proprioception training for the legs. This approach stimulates the proprioceptive system, playing a pivotal role in generating movement responses and stabilizing the joints.^10^ The researchers conducted proprioceptive training on such unstable surfaces using a variety of equipment to induce instability. These included a Swiss ball, a soft ball (BOSU), various balance foam cushions, and trampolines. The devised training regimen was usually comprehensive, involving a series of specific proprioceptive exercises. An example of such set of exercises, using a balance foam mat, is shown in Figure 7.

These were executed under both static and dynamic conditions. The participants engaged in a mix of standing, seated, kneeling, and lying postures. Regardless of the position, they always interacted with the training equipment, which provided an element of unstable support. Typically, the training process was segmented into three distinct initial, intermediate, and advanced. This structure ensured a gradual increase in the complexity and challenge of the exercises. For instance, participants were subjected to decreasing hand support during standing, deeper hip and knee bends during squatting exercises, and transitioned from training with eyes open to training with eyes closed.^10,39^ Interestingly, in the three proprioceptive training studies considered for the meta-analysis, gait training was not included.^33,40,41^ In two studies focused on proprioceptive training, exercises were performed exclusively with eyes open.^33,42^ Additional studies,^35,43^ incorporated exercises like rolling a ball with one foot while standing and standing on a foam cushion with the alternate foot. The variations in methodologies and exercises across these studies underscore the ambiguity surrounding the definition of proprioceptive training. Such discrepancies emphasize the need for a more standardized and clear understanding of what truly constitutes proprioceptive training. This would ensure consistency in research and application, providing clearer insights into its benefits and best practices.

Sensorimotor training is often discussed in the context of sensory-motor integration. This integration is facilitated by the central nervous system, which merges sensory and motor information to produce skillful and coordinated bodily movements.^44,45^ A harmonious interaction between the sensory and motor systems is essential for acquiring and executing coordinated movements. Ahmad et al.^18^ suggested that sensorimotor training focuses on enhancing the assimilation of somatosensory and proprioceptive stimuli, reducing muscle imbalances, and instituting an accurate motor program within the central nervous system. Their training regimen included balance exercises on unstable surfaces, trunk muscle strengthening, and gait training. Specific exercises included back-sliding squats on vertical surfaces, unilateral standing exercises, and toe and heel stepping on a balance mat. Additionally, exercises targeting trunk muscle strengthening and various walking patterns were incorporated. Da Silva et al.^34^ adopted a similar approach, employing a circuit training model. Their sensory-motor exercises were diverse, being executed on both stable and unstable platforms. Participants trained with both eyes open and closed, and exercises were designed for dualleg and alternating single-leg stances. Training also encompassed walking in various forward, backward, sideways, over obstacles, and upstairs. Additionally, participants adapted their walking based on auditory cues from researchers. Morat et al.^46^ emphasized that sensorimotor marching exercises are more tailored for enhancing balance and preventing falls when compared to traditional balance-enhancing exercises, such as postural holds. In their study, participants engaged in a controlled exercise regimen, focusing on a specific protocol of marching exercises in both stable and unstable settings. The training was conducted on an advanced exercise platform equipped with force sensors and a display (Dividat Senso). This platform facilitates diverse training, honing both cognitive and motor skills. The intervention encompassed 11 distinct marching tasks executed using Exergames (including Targete, Divided, Simon, Flexi, Snake, Tetris, Habitats, Birds, and Hexagon). While two tasks (Ski and Rocket) were devoid of additional cognitive challenges, the remaining games were instrumental in stimulating cognitive abilities in participants. This was achieved through exercises targeting divided and selective attention, visual-spatial working memory, mental rotation, and cognitive flexibility. Overall, the sensorimotor training content partially overlapped with proprioceptive exercise. Figure 8 shows examples of exercises found within papers investigating sensorimotor training.

Limitations and future perspectives

One of the significant limitations of this study is the grouping of studies in the meta-analyses. We included studies that focused on elderly people of both sexes, as well as studies that exclusively targeted elderly men or elderly women. While this was done in light of low number of available studies, we have to admit that by integrating these distinct studies, there is a potential risk of introducing additional heterogeneity that compromises the specificity of our findings.

Recognizing this, it is essential for future meta-analyses in this domain to adopt a more discerning approach, possibly through stratified analyses based on gender, to ensure more robust and nuanced conclusions. Another constraint we faced was the limited number of studies included in the meta-analysis, preventing subgroup analyses for most outcomes. Furthermore, it is crucial to recognize that the outcomes derived from our metaanalysis reflect only short-term effects. The lack of longterm follow-up on subjects means that the long-term impacts of the protocols remain unknown. Notwithstanding the plethora of studies on proprioceptive and sensory-motor training, a definitive understanding of these terms, their encompassed interventions, and their specific impacts on the balance of older individuals remains elusive. When evaluating the training interventions detailed in the various studies, it became apparent that there is inconsistent and, at times, incorrect usage of the terms 'proprioceptive' and 'sensorymotor' by some authors. To illustrate, when reviewing studies not included in our meta-analysis, we found that two studies described identical training interventions but labeled them differently - one as proprioceptive and the other as sensorimotor. For instance, one study classified their home-based training as sensory-motor.^47^ Yet, this training was identical to that another study,^9^ where it was labeled proprioceptive.

The prevalent, casual usage of “proprioception” in many studies is a cause for concern. Often, this term is used in contexts that refer to multi-modal sensory-motor learning tasks. Accepting a broad view that equates all forms of sensory-motor learning to proprioceptive training renders the term virtually meaningless to both the scientific and clinical realms. If a study posits proprioceptive training as a unique form of sensory training or specialized sensory-motor learning, it is imperative for clarity's sake to state this distinction explicitly. This would mitigate the potential for terminological confusion and ambiguity.^17^ Consequently, some researchers advocate for eschewing the term 'proprioceptive training' when referencing training types known to boost motor function but not proven to enhance proprioceptive function .^21,22^

In this systematic review and meta-analysis, we assessed the impact of sensorimotor and proprioceptive exercises on balance in older adults. The majority of the studies included both male and female participants with ages spanning from middle-aged to elderly. The interventions varied in frequency and duration, but consistently showed potential benefits for improving balance. Common outcome measures underscored the significance of exercises in enhancing balance, mobility, and overall proprioceptive function. The study quality was predominantly good to fair, reinforcing the validity of the findings. Overall, the evidence suggests that sensorimotor and proprioceptive exercises play a pivotal role in promoting balance and reducing fall risk in older adults. This highlights the importance of integrating such exercises into regular therapeutic and fitness regimens for the elderly population. We also observed an ambiguity and inconsistency regarding the usage of the terms proprioceptive and sensorimotor training, which should be addressed in the future.