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Volume 16, Issue 3 (2024)
3 2024, 16(3): 239-244 |
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Ethics code: IR/SSRI.REC.1402.278
History
Received: 2024/05/30 | Accepted: 2024/08/5 | Published: 2024/09/30
Received: 2024/05/30 | Accepted: 2024/08/5 | Published: 2024/09/30
How to cite this article
Nezhadmohammadi M, Zarei M, Hosseini S, Asady Samani Z. The Effect of Eight Weeks of Square Stepping Exercise on the Risk of Falls in Elderly Men. 3 2024; 16 (3) :239-244
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1- Department of Sports Rehabilitation and Health, Faculty of Sports Sciences and Health, Shahid Beheshti University, Tehran, Iran
2- Department of Physical Education and Sports Sciences, Hasht Behesht Institute of Higher Education, Isfahan, Iran
2- Department of Physical Education and Sports Sciences, Hasht Behesht Institute of Higher Education, Isfahan, Iran
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Introduction
Aging is defined as a dynamic process of increasing age that leads to a decline in functional capacity [1]. Studies indicate that the global population of individuals over 65 is rapidly growing, projected to reach 1.6 billion by 2050 [2]. In Iran, the elderly population is also steadily rising, with many considering it a future challenge due to shifts in population proportions. Aging often brings issues like reduced balance, cognitive power, and coordination. These physical and cognitive declines are generally interconnected [3, 4], leading to problems such as walking difficulties and a higher risk of falls in older adults [5, 6]. Frachi et al. report that 25% of elderly individuals experience at least one fall per year, with fall-related injury rates rising with age [7]. Additionally, fear of falling and reduced confidence can diminish performance levels [8, 9]. Magnus et al. emphasize that fall-prevention interventions should be delivered to high-risk elderly groups in a structured manner to minimize falls [10].Numerous studies have explored ways to reduce fall risk in older adults, discussing various methods [7, 10, 11]. Exercise programs are among the most effective strategies for reducing fall risk [11]. Recently, square-stepping exercises have emerged in Japan as a practical, affordable method to enhance physical and mental fitness in older adults [12]. This program aims to impact both physical and cognitive functioning. Research shows that square-stepping exercises, as an effective intervention for executive function [13] and cognitive status in the elderly, can improve physical and cognitive performance by combining physical and cognitive training. Shigematsu et al. first demonstrated in 2006 that square-stepping exercises could significantly improve balance, flexibility, agility, leg strength, and speed among older adults, thereby enhancing functional fitness. Subsequent research has investigated square-stepping exercises’ effects on postural stability and balance from various angles [12].Asadi et al. studied the three-month effects of square-stepping and resistance training on postural balance and fear of falling in elderly women in Iran, finding that square-stepping exercises could enhance postural stability and positively impact postural balance and fear of falling [14]. Recent reviews further confirm that square-stepping exercises can significantly improve dynamic balance in older adults, reducing fall risk as a result [15]. However, most studies rely on field tests, such as the Y Balance Test and various questionnaires, to assess fall risk. A recent systematic review suggests that none of these tests offer an adequate tool for evaluating fall risk in the elderly [16]. Studies show that stability measurement systems capable of simulating falls provide more accurate tools. These devices enable biomechanical assessments of balance. Perraca et al. noted that Biodex Balance System measures are highly reliable and useful for assessing fall risk and monitoring fall-prevention programs in older adults [17].
Most studies examining the effectiveness of various fall-prevention programs have focused on elderly women [18-20]. However, fall risk factors may differ by gender; for instance, women might be more prone to falls due to concerns about falling, leading to reduced physical activity and lower gait quality [21]. On the other hand, a recent systematic review reveals that older men have a higher fall risk due to combined physical and mental health limitations compared to women, particularly in the 65-74 age group [22]. This study thus aims to examine the impact of an eight-week square-stepping exercise program on fall risk in older men, using the Biodex Balance System.
Materials and Methods
This randomized clinical trial was conducted in the fall of 2023 among elderly men in day care centers in Tehran. Two active centers were identified, and male residents were invited to participate. Using G*Power software version 3.1, a sample size of 28 was calculated based on a test power of 0.80, effect size of 0.55, and alpha error of 0.05, with previous studies referenced [23]. Considering a potential dropout rate of 10%, 30 participants were enrolled and randomly assigned to either a square-stepping exercise group (n=15) or a control group (n=15). Simple randomization (lottery method) was used. All participants signed consent forms, and their medical records were reviewed for study criteria. Assessments were conducted before and eight weeks after the intervention.
Participants eligible for inclusion in this study were elderly men aged 65 and above who were able to walk independently without the need for walking aids and had no significant cognitive impairments, as assessed by a standardized cognitive test. Those who regularly engaged in physical activity or exercise programs within the last three months were excluded to minimize the influence of previous physical training on the study’s outcomes. Additionally, participants with any severe musculoskeletal, neurological, or cardiovascular disorders that could interfere with safe exercise participation or affect balance performance were also excluded from the study. During the study, one participant withdrew due to death, and another left due to lack of interest.
Fall Risk Test Implementation: The Biodex Balance System SD, made by Biodex in the U.S., was used to assess fall risk in the Sports and Wellness Sciences Laboratory at Shahid Beheshti University. This tool has high reliability and validity for evaluating fall risk in elderly men [19]. According to the protocol, participants stood on the balance platform with foot positions adjusted accordingly. Test difficulty was set at level 10 to 12 based on pilot results. Each trial lasted 20 seconds with three attempts and a 10-second rest between each. A circular target appeared on a screen in front of each participant, allowing them to adjust their spatial positioning to maintain stability. Tests were conducted with participants' eyes open for safety.
Stepping Square Exercise Protocol
The intervention group participated in monitored training sessions twice a week over an eight-week period at the Vaghte Zandegi Elderly Day Care Center. Each session included 10 minutes of warm-up activities, such as stretching and physical exercises, 40 minutes of stepping square exercises, and 10 minutes of cooling down. The stepping square exercise protocol, initially developed by Shigematsu, was performed on a grid (100 × 250 cm) with 40 squares (25 cm each) marked on the gym floor. Participants were instructed to follow a specified stepping pattern (Figure 1) from one end of the grid to the other. Once they reached the end, they were asked to return to the starting point via the right side of the grid and line up for the next stage.
Figure 1. Protocol for performing exercises (examples of beginner levels 1 and 2)
After familiarizing themselves with each stepping pattern, participants were further instructed to step on the balls of their feet (heel-high) without stepping on the square boundaries. Each pattern was repeated 4 to 10 times to ensure proficiency, and then the participants progressed to a more complex stepping pattern. In total, 196 step patterns were developed and categorized into eight levels (beginner, 1-2; intermediate, 1-3; and advanced, 1-3) based on gradually increasing complexity. Participants were encouraged to concentrate on executing increasingly complex patterns successfully. They were allowed to perform at their own pace. While they initially took 15-20 seconds to complete each basic pattern, by the final sessions, they could complete each pattern in less than 15 seconds. Given the study duration and specific conditions, only beginner levels one and two were performed in this study. Participants wore athletic shoes and attire throughout the exercises.
Data Analysis
SPSS version 26 was used for data analysis. Descriptive statistics, such as mean and standard deviation, were used to describe the data. Before conducting ANCOVA, the assumptions of homogeneity of variances (Levene's test), normality of distribution (Shapiro-Wilk test), and regression slope equality (testing the absence of interaction between covariate and independent variable) were verified. The significance level was set at 95%.
Findings
There were no significant differences between the groups in terms of age, height, weight, and body mass index (p>0.05; Table 1).
Table 1. Participants demographic characteristics
As the data met the assumptions for ANCOVA, this test was used to determine the intervention's effect. The results of Levene's test confirmed homogeneity of variance for the dependent variable (fall risk scores), and the Shapiro-Wilk test indicated a normal distribution (p>0.05). Finally, the regression slope homogeneity test showed no significant interaction between the covariate and the independent variable (p>0.05), confirming equal regression slopes across the groups (Table 2).
Table 2. Bonferroni test for comparing the effect of group and covariate (risk of falling between the two groups in the pre-test and post-test (n=28)
Following confirmation of ANCOVA assumptions, results revealed a significant main effect for the group at the post-test stage, indicating that the stepping square exercises significantly reduced fall risk in elderly men after eight weeks of training (p=0.001). According to the observed effect size, the intervention had a small effect on reducing fall risk among the elderly (Table 3).
Table 3. Analysis of Covariance (ANCOVA) test for comparing the risk of falling between the two groups in the pre-test and post-test (n=28)
Bonferroni post-hoc tests for estimated marginal means also demonstrated that stepping square exercises were more effective in reducing fall risk in the intervention group (2.33) compared to the control group (4.88).
Discussion
This clinical trial was conducted to examine the effect of stepping square exercises on fall risk in elderly men, measured using a balance assessment device. After eight weeks, we observed a significant reduction in fall risk among elderly men who performed these exercises.
Several similar studies have investigated the impact of stepping square exercises on fall risk [24]. For instance, Teixeira et al. have found out that stepping square exercises significantly reduces fall risk compared to a non-exercising control group [11]. Shigematsu et al. also report a decrease in fall risk following stepping square exercises, although the effect was comparable to a control group engaging in daily outdoor walking [19]. In a recent systematic review, Wang et al. suggest that these exercises can effectively reduce fall risk [25]. The observed improvements in fall risk reduction may reflect benefits related to sequential center of gravity shifts, toe-standing, and single-leg stances, which challenge balance control during the exercises [25].
Orr et al. conducted a study showing that light-load foot strengthening exercises (20% max strength) improve balance by keeping muscles active during the concentric phase of walking, thus maintaining output force. The exercise intensity and movements in their study are comparable to our stepping exercises, incorporating slight knee and ankle bends. Foot exercises like these are presumed to enhance neuromuscular function by reducing response delay, improving postural muscle engagement, and enhancing sensory information processing [26]. Furthermore, multidirectional steps i.e. forward, backward, lateral, and diagonal, engaged during stepping exercises likely result in better activation of foot synergist and agonist muscles. Thus, stepping square exercises may reduce fall risk by improving muscle strength and timing.
A meta-analysis by Fisseha et al. reveals that stepping square exercises effectively reduce fear of falling, which improves balance in older adults. These researchers conclude that these exercises improve balance by enhancing reaction time, feedback, and correction processes, based on active and reactive responses [27]. Other review studies in 2017 and 2020 indicate that exercise alone, or in combination with other interventions, can reduce fall risk and related injuries, aligning with the current study's findings [28, 29]. Gillespie et al. highlighte that home-based exercises are effective for fall risk reduction. Balance exercises conducted three times per week can reduce fall risk by up to 40% [30]. Stepping square exercises are conducted under the guidance of a coach and sports specialist, which may enhance training effectiveness.. Another study explores the effect of Biodex balance training on fall risk in elderly individuals with COPD, showing that combining Biodex-based balance training with standard balance and respiratory exercises yields better results in managing balance impairment and fall risk in COPD patients [31].
Stepping square exercises, a type of gait training, are group-friendly, low-cost, and require minimal equipment, making them suitable for indoor settings, free from challenges posed by outdoor conditions like rain or cold, which may hinder elderly participation. These exercises incorporate physical and cognitive engagement and, as a group activity, have the potential to improve social interactions among older adults. Based on prior studies, stepping square exercises are recommended as a practical and effective approach to reducing fall risk and improving balance in elderly individuals. The main limitation of this study was the training duration. Most studies have suggested that stepping square exercises should be conducted for at least 12 weeks for optimal effectiveness; however, time constraints prevented this in our study. Additionally, the relatively wide age range used due to limited participant availability may limit the generalizability of the results.
Conclusion
Performing Square stepping exercises (SSE) reduces the risk of falling in elderly men
Acknowledgments: We extend our sincere gratitude to the managers and elderly residents of the Vaqt-e Zendegi senior day care center for their participation in this study and for facilitating the implementation process.
Ethical Approvals: The ethical code for this study was approved and registered by the Ethics Committee of the Research Institute of Physical Education and Sport Sciences under code IR/SSRI.REC.1402.278. Additionally, the study is registered in the Iranian Registry of Clinical Trials with code IRCT20230124057206N1. It is worth noting that study participants were blinded to their training program and group allocation, making this study single-blind.
Conflict of Interest: The authors have reported no conflicts of interest.
Author Contributions: Nezhadmohammadi MJ (First Author), Introduction Writer/Main Researcher/Statistical Analyst (35%); Zarei M (Second Author), /Methodologist/Original Researcher/Discussion Writer (30%); Hosseini SM (Third Author), Introduction Writer/Methodologist/Discussion Writer (20%); Asadi Samani Z (Fourth Author), Methodologist/Statistical Analyst (15%)
Fundings: This article is derived from the Master’s thesis of Mr. Mohammad Javad Nejad Mohammadi.
Aging is defined as a dynamic process of increasing age that leads to a decline in functional capacity [1]. Studies indicate that the global population of individuals over 65 is rapidly growing, projected to reach 1.6 billion by 2050 [2]. In Iran, the elderly population is also steadily rising, with many considering it a future challenge due to shifts in population proportions. Aging often brings issues like reduced balance, cognitive power, and coordination. These physical and cognitive declines are generally interconnected [3, 4], leading to problems such as walking difficulties and a higher risk of falls in older adults [5, 6]. Frachi et al. report that 25% of elderly individuals experience at least one fall per year, with fall-related injury rates rising with age [7]. Additionally, fear of falling and reduced confidence can diminish performance levels [8, 9]. Magnus et al. emphasize that fall-prevention interventions should be delivered to high-risk elderly groups in a structured manner to minimize falls [10].Numerous studies have explored ways to reduce fall risk in older adults, discussing various methods [7, 10, 11]. Exercise programs are among the most effective strategies for reducing fall risk [11]. Recently, square-stepping exercises have emerged in Japan as a practical, affordable method to enhance physical and mental fitness in older adults [12]. This program aims to impact both physical and cognitive functioning. Research shows that square-stepping exercises, as an effective intervention for executive function [13] and cognitive status in the elderly, can improve physical and cognitive performance by combining physical and cognitive training. Shigematsu et al. first demonstrated in 2006 that square-stepping exercises could significantly improve balance, flexibility, agility, leg strength, and speed among older adults, thereby enhancing functional fitness. Subsequent research has investigated square-stepping exercises’ effects on postural stability and balance from various angles [12].Asadi et al. studied the three-month effects of square-stepping and resistance training on postural balance and fear of falling in elderly women in Iran, finding that square-stepping exercises could enhance postural stability and positively impact postural balance and fear of falling [14]. Recent reviews further confirm that square-stepping exercises can significantly improve dynamic balance in older adults, reducing fall risk as a result [15]. However, most studies rely on field tests, such as the Y Balance Test and various questionnaires, to assess fall risk. A recent systematic review suggests that none of these tests offer an adequate tool for evaluating fall risk in the elderly [16]. Studies show that stability measurement systems capable of simulating falls provide more accurate tools. These devices enable biomechanical assessments of balance. Perraca et al. noted that Biodex Balance System measures are highly reliable and useful for assessing fall risk and monitoring fall-prevention programs in older adults [17].
Most studies examining the effectiveness of various fall-prevention programs have focused on elderly women [18-20]. However, fall risk factors may differ by gender; for instance, women might be more prone to falls due to concerns about falling, leading to reduced physical activity and lower gait quality [21]. On the other hand, a recent systematic review reveals that older men have a higher fall risk due to combined physical and mental health limitations compared to women, particularly in the 65-74 age group [22]. This study thus aims to examine the impact of an eight-week square-stepping exercise program on fall risk in older men, using the Biodex Balance System.
Materials and Methods
This randomized clinical trial was conducted in the fall of 2023 among elderly men in day care centers in Tehran. Two active centers were identified, and male residents were invited to participate. Using G*Power software version 3.1, a sample size of 28 was calculated based on a test power of 0.80, effect size of 0.55, and alpha error of 0.05, with previous studies referenced [23]. Considering a potential dropout rate of 10%, 30 participants were enrolled and randomly assigned to either a square-stepping exercise group (n=15) or a control group (n=15). Simple randomization (lottery method) was used. All participants signed consent forms, and their medical records were reviewed for study criteria. Assessments were conducted before and eight weeks after the intervention.
Participants eligible for inclusion in this study were elderly men aged 65 and above who were able to walk independently without the need for walking aids and had no significant cognitive impairments, as assessed by a standardized cognitive test. Those who regularly engaged in physical activity or exercise programs within the last three months were excluded to minimize the influence of previous physical training on the study’s outcomes. Additionally, participants with any severe musculoskeletal, neurological, or cardiovascular disorders that could interfere with safe exercise participation or affect balance performance were also excluded from the study. During the study, one participant withdrew due to death, and another left due to lack of interest.
Fall Risk Test Implementation: The Biodex Balance System SD, made by Biodex in the U.S., was used to assess fall risk in the Sports and Wellness Sciences Laboratory at Shahid Beheshti University. This tool has high reliability and validity for evaluating fall risk in elderly men [19]. According to the protocol, participants stood on the balance platform with foot positions adjusted accordingly. Test difficulty was set at level 10 to 12 based on pilot results. Each trial lasted 20 seconds with three attempts and a 10-second rest between each. A circular target appeared on a screen in front of each participant, allowing them to adjust their spatial positioning to maintain stability. Tests were conducted with participants' eyes open for safety.
Stepping Square Exercise Protocol
The intervention group participated in monitored training sessions twice a week over an eight-week period at the Vaghte Zandegi Elderly Day Care Center. Each session included 10 minutes of warm-up activities, such as stretching and physical exercises, 40 minutes of stepping square exercises, and 10 minutes of cooling down. The stepping square exercise protocol, initially developed by Shigematsu, was performed on a grid (100 × 250 cm) with 40 squares (25 cm each) marked on the gym floor. Participants were instructed to follow a specified stepping pattern (Figure 1) from one end of the grid to the other. Once they reached the end, they were asked to return to the starting point via the right side of the grid and line up for the next stage.
Figure 1. Protocol for performing exercises (examples of beginner levels 1 and 2)
After familiarizing themselves with each stepping pattern, participants were further instructed to step on the balls of their feet (heel-high) without stepping on the square boundaries. Each pattern was repeated 4 to 10 times to ensure proficiency, and then the participants progressed to a more complex stepping pattern. In total, 196 step patterns were developed and categorized into eight levels (beginner, 1-2; intermediate, 1-3; and advanced, 1-3) based on gradually increasing complexity. Participants were encouraged to concentrate on executing increasingly complex patterns successfully. They were allowed to perform at their own pace. While they initially took 15-20 seconds to complete each basic pattern, by the final sessions, they could complete each pattern in less than 15 seconds. Given the study duration and specific conditions, only beginner levels one and two were performed in this study. Participants wore athletic shoes and attire throughout the exercises.
Data Analysis
SPSS version 26 was used for data analysis. Descriptive statistics, such as mean and standard deviation, were used to describe the data. Before conducting ANCOVA, the assumptions of homogeneity of variances (Levene's test), normality of distribution (Shapiro-Wilk test), and regression slope equality (testing the absence of interaction between covariate and independent variable) were verified. The significance level was set at 95%.
Findings
There were no significant differences between the groups in terms of age, height, weight, and body mass index (p>0.05; Table 1).
Table 1. Participants demographic characteristics
As the data met the assumptions for ANCOVA, this test was used to determine the intervention's effect. The results of Levene's test confirmed homogeneity of variance for the dependent variable (fall risk scores), and the Shapiro-Wilk test indicated a normal distribution (p>0.05). Finally, the regression slope homogeneity test showed no significant interaction between the covariate and the independent variable (p>0.05), confirming equal regression slopes across the groups (Table 2).
Table 2. Bonferroni test for comparing the effect of group and covariate (risk of falling between the two groups in the pre-test and post-test (n=28)
Following confirmation of ANCOVA assumptions, results revealed a significant main effect for the group at the post-test stage, indicating that the stepping square exercises significantly reduced fall risk in elderly men after eight weeks of training (p=0.001). According to the observed effect size, the intervention had a small effect on reducing fall risk among the elderly (Table 3).
Table 3. Analysis of Covariance (ANCOVA) test for comparing the risk of falling between the two groups in the pre-test and post-test (n=28)
Bonferroni post-hoc tests for estimated marginal means also demonstrated that stepping square exercises were more effective in reducing fall risk in the intervention group (2.33) compared to the control group (4.88).
Discussion
This clinical trial was conducted to examine the effect of stepping square exercises on fall risk in elderly men, measured using a balance assessment device. After eight weeks, we observed a significant reduction in fall risk among elderly men who performed these exercises.
Several similar studies have investigated the impact of stepping square exercises on fall risk [24]. For instance, Teixeira et al. have found out that stepping square exercises significantly reduces fall risk compared to a non-exercising control group [11]. Shigematsu et al. also report a decrease in fall risk following stepping square exercises, although the effect was comparable to a control group engaging in daily outdoor walking [19]. In a recent systematic review, Wang et al. suggest that these exercises can effectively reduce fall risk [25]. The observed improvements in fall risk reduction may reflect benefits related to sequential center of gravity shifts, toe-standing, and single-leg stances, which challenge balance control during the exercises [25].
Orr et al. conducted a study showing that light-load foot strengthening exercises (20% max strength) improve balance by keeping muscles active during the concentric phase of walking, thus maintaining output force. The exercise intensity and movements in their study are comparable to our stepping exercises, incorporating slight knee and ankle bends. Foot exercises like these are presumed to enhance neuromuscular function by reducing response delay, improving postural muscle engagement, and enhancing sensory information processing [26]. Furthermore, multidirectional steps i.e. forward, backward, lateral, and diagonal, engaged during stepping exercises likely result in better activation of foot synergist and agonist muscles. Thus, stepping square exercises may reduce fall risk by improving muscle strength and timing.
A meta-analysis by Fisseha et al. reveals that stepping square exercises effectively reduce fear of falling, which improves balance in older adults. These researchers conclude that these exercises improve balance by enhancing reaction time, feedback, and correction processes, based on active and reactive responses [27]. Other review studies in 2017 and 2020 indicate that exercise alone, or in combination with other interventions, can reduce fall risk and related injuries, aligning with the current study's findings [28, 29]. Gillespie et al. highlighte that home-based exercises are effective for fall risk reduction. Balance exercises conducted three times per week can reduce fall risk by up to 40% [30]. Stepping square exercises are conducted under the guidance of a coach and sports specialist, which may enhance training effectiveness.. Another study explores the effect of Biodex balance training on fall risk in elderly individuals with COPD, showing that combining Biodex-based balance training with standard balance and respiratory exercises yields better results in managing balance impairment and fall risk in COPD patients [31].
Stepping square exercises, a type of gait training, are group-friendly, low-cost, and require minimal equipment, making them suitable for indoor settings, free from challenges posed by outdoor conditions like rain or cold, which may hinder elderly participation. These exercises incorporate physical and cognitive engagement and, as a group activity, have the potential to improve social interactions among older adults. Based on prior studies, stepping square exercises are recommended as a practical and effective approach to reducing fall risk and improving balance in elderly individuals. The main limitation of this study was the training duration. Most studies have suggested that stepping square exercises should be conducted for at least 12 weeks for optimal effectiveness; however, time constraints prevented this in our study. Additionally, the relatively wide age range used due to limited participant availability may limit the generalizability of the results.
Conclusion
Performing Square stepping exercises (SSE) reduces the risk of falling in elderly men
Acknowledgments: We extend our sincere gratitude to the managers and elderly residents of the Vaqt-e Zendegi senior day care center for their participation in this study and for facilitating the implementation process.
Ethical Approvals: The ethical code for this study was approved and registered by the Ethics Committee of the Research Institute of Physical Education and Sport Sciences under code IR/SSRI.REC.1402.278. Additionally, the study is registered in the Iranian Registry of Clinical Trials with code IRCT20230124057206N1. It is worth noting that study participants were blinded to their training program and group allocation, making this study single-blind.
Conflict of Interest: The authors have reported no conflicts of interest.
Author Contributions: Nezhadmohammadi MJ (First Author), Introduction Writer/Main Researcher/Statistical Analyst (35%); Zarei M (Second Author), /Methodologist/Original Researcher/Discussion Writer (30%); Hosseini SM (Third Author), Introduction Writer/Methodologist/Discussion Writer (20%); Asadi Samani Z (Fourth Author), Methodologist/Statistical Analyst (15%)
Fundings: This article is derived from the Master’s thesis of Mr. Mohammad Javad Nejad Mohammadi.
Keywords: