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Article

Examining Performance between Different Cognitive-Motor Dual-Task Tests in Community-Dwelling Older Adults

by
Anastasios Georgantas
1,
Panagiota Stefani
1,
Epameinondas Lyros
1,
Dimitrios Chytas
1 and
Anna Christakou
2,3,*
1
Lab Basic Sciences, Department of Physiotherapy, School of Health Sciences, University of Peloponnese, 23100 Sparta, Greece
2
Lab Biomechanics, Department of Physiotherapy, School of Health Sciences, University of Peloponnese, 23100 Sparta, Greece
3
Department of Physiotherapy, University of West Attica, 12243 Athens, Greece
*
Author to whom correspondence should be addressed.
Appl. Sci. 2024, 14(17), 7957; https://doi.org/10.3390/app14177957
Submission received: 2 August 2024 / Revised: 30 August 2024 / Accepted: 3 September 2024 / Published: 6 September 2024
Browse Figures
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Abstract

:
Performing dual-task (DT) activities is essential for independent living among elderly people. No study has investigated motor performance in various cognitive-motor DT activities, utilizing the Timed Up and Go (TUG) test. This study aimed to compare motor performance between four cognitive-motor DT tests in community-dwelling older adults. The sample consisted of 60 older women. The cognitive tasks performed with the TUG test were (a) mental calculation, (b) memory recall, (c) verbal fluency, and (d) reaction to a stimulus. Lower limb muscle strength was assessed with the 30-Second Chair Stand Test, balance with the Four Square Step Test, and balance confidence with the Activities-specific Balance Confidence Scale. Completion times and DT costs were calculated. Mental calculation (r = 0.63, p < 0.01) and verbal fluency (r = 0.65, p < 0.01) tasks were similarly correlated with the TUG test, and significantly impacted motor performance compared to other DT tests. The reaction to a stimulus test showed a high relationship with the TUG test (r = 0.89, p < 0.01) and had the least impact on motor performance. These findings suggest that the cognitive task type can significantly influence motor performance during DT activities. Adding a cognitive load to the TUG test may improve its ability to identify older adults at risk for falls, aiding in the development of targeted interventions. Further research is required to validate these findings.

1. Introduction

Dual-task (DT) refers to the concurrent execution of two distinct activities that can be carried out independently, assessed individually, and have separate objectives [1]. This involves performing multiple tasks at the same time, such as walking while simultaneously engaging in a verbal and/or motor task. The successful performance of two simultaneous activities may be considered difficult; in fact, a previous study has reported that people have limited cognitive capacity (attentional capacity theory) [2]. Moreover, a recent study confirmed that in a healthy young population the execution of two simultaneous tasks, requiring the same cognitive resources, leads to a decrease in efficiency in one or both (dual task effect), causing cognitive fatigue with the increasing complexity of one or both tasks [3]. This interference phenomenon is especially emphasized when simultaneous activities are performed by elderly.
Impaired physical activity and cognitive dysfunction due to aging are common, which results in decreased performance in one or both tasks when performed together [4]. Also, the exponential increase in the geriatric population in combination with negative changes due to morphological and pathological disorders are factors contributing to the increasing frequency of falls [5]. Identifying the risk factors which lead to falls and designing appropriate preventative interventions has become of utmost importance. The performance of a DT activity may impair both dynamic balance and cognitive function in the elderly, which leads to this increase in falls [6,7].
Most studies examining older people’s performance in DT activities include one motor task and one cognitive task [8,9]. Executive functions in the elderly comprising working memory, inhibitory control, and cognitive flexibility are considered essential for the proper response to and resolution of everyday life problems [10,11]. Choosing the appropriate cognitive activity during DT assessment can provide important information about older people’s mobility and significantly increase the sensitivity of assessment tests to predict falls. Cognitive tasks that require more complex processing such as the calculation of mental arithmetic operations (working memory) and verbal fluency have been demonstrated to interfere with motor behaviors to a greater extent than tasks that involve automatic central processing, such as reaction time [12]. Nonetheless, geriatric research has not extensively examined how task dependency influences DT gait [13].
The motor tasks typically used involve either the 6- to 10-m gait tests or the TUG test [14]. Tests that involve leaning from a chair, walking, and turning, such as the Timed Up and Go (TUG) test, appear to provide important information compared to the walking tests [14]. Although gait tests can highlight to a greater extent the motor performance of older people, it is often not feasible to evaluate them in a clinical setting due to the lack of necessary space and equipment. In the realm of DT gait, studies typically examine walking forward [14]. Even though turning is a common transition movement during walking, it has not received much attention despite its importance in daily life. Turning is particularly interesting because, even in settings where there is just one task involved, this fleeting motor activity is strongly associated with instability. The distinct physiological and cognitive demands of turns (in contrast to straight-ahead walking) may be the cause of this instability. One such requirement is the cognitive processing of speed [15]. In fact, turning is believed to be more than a reflexive movement; it requires cognitive processing. This involves synthesizing information from the vestibular, somatosensory, and visual systems in order to give feedback and appropriately regulate the body while in motion [16].
The TUG is a clinically valid and reliable test suggested as a tool for assessing fall risk [17] however, it is argued to have limited ability to predict falls for community-dwelling older adults [18] because TUG does not account for the cognitive factors that appear to correlate with fall risk. It may offer promising results for predicting falls compared to gait tests when it is part of a DT activity [14]. Adding a cognitive load to the TUG test could enhance its effectiveness in identifying individuals at a high risk of falling [8].
A limitation of previous studies that assessed older individuals′ performance in DT activities utilizing the TUG test is the selection of only one cognitive task [8,19,20]. Mental number subtraction, usually performed alongside the TUG, is a test that burdens the individual’s working memory, without investigating other cognitive abilities such as memory recall, verbal fluency, and response to a stimulus. This limited approach restricts our understanding of how different cognitive demands influence motor performance in older adults. The assessment of older individuals′ performance in different cognitive-motor DT activities using the TUG test has so far not been investigated. Almajid & Keshner [21] examined motor performance in a sample of young adults in these different cognitive-motor DT TUG tests and suggest conducting a similar study in elderly population.
Therefore, the purpose of the current study was to compare motor performance between four different cognitive-motor dual-task activities in community-dwelling older adults, using the TUG test. The cognitive tasks selected—mental calculation, verbal fluency, memory recall, and verbal reaction to auditory stimuli—were chosen to reflect varying cognitive demands relevant to daily activities. We hypothesized that (a) all the DT tests would overload motor performance over time compared to the simple TUG test because of the added cognitive load; (b) the mental calculation and verbal fluency tasks would overload motor performance over time more than the performance of a simple TUG test, owing to their higher cognitive demands; (c) the verbal reaction to auditory stimuli task would overload motor performance less over time than the performance of a simple TUG test, as it involves less complex cognitive processing.

2. Materials and Methods

2.1. Participants

The sample included 60 elderly women with an average age of 72.22 ± 5.11 years from a community senior center in the Marousi Municipality (Athens, Greece). The inclusion criteria were: (a) elderly people aged 65 to 80 years, (b) female gender, (c) residence in the community, (d) a sufficient ability to understand, write, and speak the Greek language, (e) the ability to perform mental arithmetic operations involving the subtraction of three numbers, (f) the ability to walk independently without relying on any assistive equipment. The exclusion criteria included: (a) having a diagnosis of Parkinson’s disease, stroke, multiple sclerosis, brain tumor, or traumatic brain injury, (b) scoring below 23 on The Mini Mental State Examination (MMSE), (c) having inner ear, brain stem, or cerebellar conditions that could lead to dizziness or falls, (d) using psychoactive drugs or medications that cause confusion or orthostatic hypotension, (e) having vision and hearing problems that impact the ability to perform daily living activities.
The demographics characteristics of the sample are shown in Table 1 and in Table S1 (as Supplementary Materials). Additional sample characteristics were also assessed, such as: (a) functional lower limb muscle strength with the 30-Second Chair Stand Test (30-CST), (b) dynamic balance with the Four Square Step Test (FSST) and (c) balance confidence with the Activities-specific Balance confidence (ABC) scale (Table 1).

2.2. Measures and Instruments

The present study included valid measures such as:
(a)
The Timed Up and Go (TUG) test is a simple and quick assessment tool commonly used to evaluate fall risk in the elderly population. When administered, it records the time taken for a person to rise from a straight-backed chair, walk 3 m, turn around, return to the chair, and sit back down. This is a valid and reliable test, as according to Podsiadlo & Richardson [22] it showed good test-retest reliability (ICC = 0.99) and good inter-rater reliability (ICC = 0.99). The TUG was the motor task completed during the performance of both the single activity and the DT activities in the present study. To measure the necessary distance for the TUG test, a tape measure and a plastic cone were used, which was placed at 3 m from the chair. A digital stopwatch was then employed to record the time of test completion.
(b)
The 30-S Chair Stand Test (30-CST) assesses the functional muscle strength of the lower limbs [23]. The participant sits in the center of a straight-backed chair, approximately 43 cm tall, with no side supports, with the back straight, feet on the floor slightly behind the knees, and arms crossed over the chest. The subject is encouraged to complete as many full raises and chair sits as possible within 30 s, while the examiner is counting the number of raises. Being able to perform more repetitions indicates higher lower limb strength. According to Jones et al. [23], the test showed excellent criterion validity: r = 0.77 (95% CI = 0.64–0.85) compared to weight-adjusted lower limb strength performance for all participants. Also, excellent test-retest reliability was recorded for the entire sample: r = 0.89 (95% CI = 0.79–0.93), and excellent inter-rater reliability in a pilot test among 15 participants: r = 0.95 (95% CI = 0.84–0.97).
(c)
The Four Square Step Test (FSST) assesses dynamic balance [24]. The participant is asked to step over 4 bars in a cross (+) configuration on a flat surface without touching them and to move as fast as possible in each square with both feet forward, right, backward, and left (clockwise and counterclockwise). Two trials are conducted, and the time for each is recorded in seconds. The best time is then chosen for further analysis. According to Dite & Temple [24], the FSST showed excellent concurrent validity with the Step Test (r = −0.83) and the Timed Up and Go (r = 0.88), and adequate concurrent validity with the Functional Reach Test (r = −0.47). Excellent test-retest reliability (ICC = 0.98) and excellent inter-rater reliability (ICC = 0.99) were also recorded.
(d)
The Activities-Specific Balance Confidence (ABC) scale is employed to evaluate older people’s balance confidence. This is a 16-question activity scale where the individual is asked to rate their confidence in performing supposed daily activities without losing balance or feeling unstable. Each question is scored from 0 (no confidence) to 100 (full confidence), and the final score is obtained by summing all the scores and then dividing by the number of questions [25]. The ABC scale has been translated and adapted for a Greek elderly population by Makri et al. [26] with high validity and reliability.

2.3. Procedure

The study was approved by the Research Ethics Committee of the University of the Peloponnese (5365/11-03-2024) and it was conducted in accordance with the Declaration of Helsinki. Data collection was carried out by the authors in a specific room of the community senior center. Only the first authors and each participant were present in the room. Each participant came at a scheduled day and time. The order in which the participants′ data were collected was as follows:
(a)
Collection of demographic data characteristics. Muscle strength was evaluated with the 30-CST test, dynamic balance using the FSST test, and balance confidence using the ABC scale.
(b)
Performing the TUG test (simple activity): Each participant sat in a straight-backed chair, about 46 cm high, with their back touching the back of the chair. On the authors′ ‘Go′ command, the participant stood up, walked straight at a normal walking pace towards the cone (placed 3 m from the chair), walked around the cone (on either side) and returned to the chair at the same walking pace, where she was seated. The time to complete the test was recorded until the subject came into contact with the chair.
(c)
The simultaneous execution of TUG and cognitive tasks (DT activities) as represented in Almajid & Keshner’s study [21].
In all participants, the following DT tests were performed in random order [16]:
(a)
Mental calculation (working memory): Participants performed backward counting by threes from a randomly chosen three-digit number while simultaneously executing the TUG test (TUGMC).
(b)
Memory (memory recall): Participants were asked to memorize a seven-item shopping list after reading it for 15 s while seated. Then, when the DT was conducted, they tried to recall as many products from the list as possible while performing the TUG test (TUGME). This task was never given as the first task, even though the cognitive tasks were randomized. This approach was used to confirm that each participant retained the information for a significant period before recalling it, rather than just verbalizing the items immediately after reading them.
(c)
Verbal fluency: Participants needed to generate as many words as they could starting with the letter “L” while simultaneously performing the TUG test (TUGVF).
(d)
Reaction time: Participants were asked to respond verbally to an auditory stimulus while they were performing the TUG test (TUGRE). Throughout the TUG, they heard the word “book” as a prerecorded auditory stimulus of the same intensity and at a random rate, to which they responded as quickly as possible by uttering the word “top”. The intensity and tempo of the word signal was the same for all participants.
For the calculation of motor performance during the TUG as simple activity (SA) and the TUGMC, TUGME, TUGVF, and TUGRE activities, the time taken to complete the tests (measured in seconds) was noted. Higher values correspond to worse motor performance. In addition, the dual-task costs (DTC) were calculated as the difference between the DT and the simple activity on TUG test performance (in seconds), normalized with the simple activity performance and expressed as a percentage based on the equation:
DTC (%) = − (SA performance − DT performance)/(DT performance) × 100
A negative value signifies a decline in performance (i.e., dual-task cost) relative to the performance of the single-task activity (TUG) [27].

2.4. Statistical Analysis

Descriptive statistics including the mean (M), standard deviation (SD), minimum (minimum), and maximum (maximum) values were calculated. To check the normality of the variables, the Kolmogorov–Smirnov test was applied, which confirmed the normal distribution of data related to participants′ muscle strength, dynamic balance, balance confidence, the time of the TUG test, dual-task (DT) tests, and dual-task costs (DTCs). Therefore, Pearson’s r correlational analyses were performed for all variables. Paired t-tests between the participants’ characteristics, the TUG tests, and the DTCs were performed. All statistical analyses were conducted employing the Statistical Package for the Social Sciences (SPSS version 29.0, SPSS Inc., Chicago, IL, USA) with a significance level set at α = 0.05.

3. Results

Table 2 presents the descriptive statistics of the TUG test and the four different DT tests. Results for the TUG tests are expressed in seconds. All the DT tests had longer durations than the single TUG test. Among the DT tests, the one with the longest duration is the mental calculation Timed Up and Go test (TUGMC), while the test with the shortest duration is the reaction Timed Up and Go test (TUGRE). Table 2 also presents the dual-task costs (DTCs) of the four DT tests which are expressed in percentages (%).
Paired t-tests showed statistically significant differences between the three additional sample characteristics (30-CST, FSST, and ABC) (p < 0.001) (Table 3). Statistically significant differences in performance between the TUG test and the four DT tests (p < 0.001) were shown. Also, the paired t-tests demonstrated significant differences in the DTCs between the DT tests (p < 0.001).
Pearson r correlation analysis between the TUG test and the DT tests showed positive correlations for all the tests, which were statistically significant (p < 0.01) (Table 4, Figure 1).
Pearson’s r correlation analysis between the TUG tests and the three additional physical attributes (muscle strength, balance, and balance confidence) are shown in Table 5.

4. Discussion

4.1. Comparisons of Motor Performance between the DT and TUG Tests

The study’s results indicated that, among the community-dwelling elderly women, not only there was a decrease in motor performance in the DT activities compared to the simple motor activity, but also a different response to the demands of the four dual-task conditions.
Initially, all four different cognitive-motor DT activities, utilizing the TUG test, were found to be more challenging for all participants. This was evident from the longer time needed to complete these tasks, compared to the TUG performed as a simple activity, verifying the first research hypothesis. Comparing motor performance between the different DT tests, it was found that the type of cognitive task modulated the magnitude of the reduction in performance on the TUG test with DT in this sample. The mental calculation test (TUGMC) was performed with the longest duration among the four DT tests. This indicates that it contributed to the greater reduction in motor performance compared to the single TUG test, as evidenced by the high rates of DTCs. The DT test involving verbal fluency (TUGVF) showed a smaller but similar decrease in motor performance compared to the TUGMC test. This is also shown by the high relationship between the tests, where the TUGMC and TUGVF tests showed a similar positive correlation with the TUG test, verifying the second research hypothesis. Moreover, among the four DT tests, the DT test involving verbal reaction to an auditory stimulus (TUGRE) showed the smallest change in motor performance compared to the simple TUG test, as shown by the high relationship between these two tests. That is, the TUGRE test appears to have been the easiest cognitive-motor DT test for this sample, verifying the third research hypothesis. Finally, the memory recall test (TUGME) showed a smaller increase in execution time than the TUGMC and TUGVF tests and a larger increase in execution time than the TUGRE test, thus being characterized as being of moderate difficulty.
The selection of cognitive task is a key contributor to an older person’s motor performance during the performance of a DT task. These results align with the findings of Al-Yahya et al.’s meta-analysis [12]. The simultaneous performance of mental calculations or verbal fluency cognitive tasks in combination with a motor task disrupted motor behavior more than performing a cognitive-motor DT test involving a stimulus reaction task. Also, the same meta-analysis [12] reported that the working memory task led to a significant modulation of the DT test. Activities that induce internal interference, such as TUGMC and TUGVF, may interfere with gait measurements more than activities that induce external interference, such as TUGRE. Walking leads to heightened brain activity in the primary sensorimotor and supplementary motor regions within the frontal and parietal lobes [28]. Except for the TUGRE test, all the other cognitive tests are accompanied by brain activities that are interrelated with those that control movement. During the performance of a verbal fluency task, activation is observed in the frontal and prefrontal regions [29]. Conversely, cognitive tasks involving reaction to auditory stimuli are typically automatic and depend largely on subcortical neural networks. As a result, they tend to cause less disruption to motor behavior during DT activities [12]. The findings of this study align with those of previous studies where mental number subtraction [30] and recitation of alternating letters of the alphabet [31] generally compromised gait performance in older people. A greater DTC was reported in gait during the reverse counting test compared to gait during the alternating letter recitation test [32]. According to the theories of capacity sharing [33] and bottleneck [34], attempting to execute two tasks at once can alter performance on either or both tasks due to limited attentional resources. Our findings confirmed the aforementioned theories as we observed that increased difficulty in the counting task led to higher competition for attentional resources, resulting in a more significant impact on TUG performance. Most likely, the mental calculation task utilized more of the same cortical networks as the gait task compared to the verbal fluency task, which resulted in a greater reduction in TUG performance.
The assessment of the elderly living independently in the community in DT activities involving a motor and a cognitive task aims to better understand their daily mobility, since walking and general activities of daily living are often carried out simultaneously with one or more motor or cognitive tasks. The tests used in this study typically assess gait with two tasks, and each of them involves a specific cognitive process. Although there are not many studies comparing all four different cognitive-motor tests of DT in an elderly sample, the results of the present study are similar to those of Goh et al. [35]. In particular, Goh et al. [35] compared the same cognitive-motor DT tests in a sample of 20 elderly men and women and found the same results, i.e., that the mental counting and verbal fluency tests showed the greatest change in motor performance compared to the simple motor task. The motor task involved an 8-m gait test in a straight line for 30 s at a normal pace on an electronic treadmill, where it was possible to record the DTC of gait speed. As reported by Smith et al.’s systematic review [36], healthy community-dwelling older adults with an average gait speed exceeding 1.0 m/s experience a significant reduction in gait speed when a secondary cognitive task is added.
The use of similar equipment (electronic treadmill) by Goh et al. [35] offers significant advantages in terms of recording the spatiotemporal aspects of gait, and contributes to a more reliable assessment of motor performance. But other previous studies [3,37] used 3D-motion analysis instrumentation in order to assess the spontaneous walking of the subject during dual-task execution. However, the often high cost of this equipment combined with the increased dimensional space required for effective gait assessment makes this protocol difficult to implement. In this study, the TUG test was the motor task utilized in the DT tests to record changes in motor performance. It is an easy and quick test that partially simulates everyday life conditions, as it includes multiple “motor stages”, such as lifting from a chair, walking, and turning, without requiring expensive equipment and a large dimensional space. Previous studies have assessed older adults′ performance on the TUG by adding a cognitive task, like counting backward by threes [19], counting backwards from 100 [20], or answering continuous simple subtraction questions [8]. In all of the DT tests, a decline in motor performance was noted compared to the simple TUG test. Despite the aforementioned advantages of the TUG test, examining motor performance of the elderly in cognitive-motor DT tests that include different cognitive tests and comparing them utilizing the TUG has not been investigated. Almajid & Keshner [21] examined the motor performance of men and women while performing different DT tests using the TUG along with the same cognitive tasks in the current study and came to the same results. The verbal fluency test affected the spatial and temporal measures of the participants′ gaits more than the reaction test. However, the sample was small and did not include older people.
These results offer valuable insights into the simultaneous performance of motor and cognitive tasks in community-dwelling older adults, highlighting their increased difficulty in managing mobility when performing DT activities. This difficulty mirrors the real-life challenges faced by this population in daily activities, where multiple tasks are often performed simultaneously. These findings emphasize the importance for health professionals of selecting and applying appropriate cognitive and motor assessments, such as the TUG combined with cognitive tasks that impact gait (e.g., working memory tests). Such assessments may provide a more accurate evaluation of fall risk and can inform the development of intervention programs aimed at improving DT performance and preventing falls in older adults. Utilizing these types of tests in clinical practice, depending on available time and space, could enhance the understanding of cognitive-motor interactions and contribute to better fall prevention strategies.

4.2. Examining the Relationship of Additional Characteristics with the TUG Tests

A positive direct proportional relationship was found between balance and TUG tests in the present study. That is, as the FSST test duration time increased, the TUG test duration time increased and vice versa. The FSST is more related to the simple TUG test and less related to the TUGMC and TUGVF. Several studies have found a relationship between dual-task and balance tests. Ansai et al. [38] used the single lower limb standing test to test static balance and the tandem test to test dynamic balance. The DT tests were a motor test and a cognitive test combined with the TUG. In the cognitive DT test, participants performed the TUG test and simultaneously repeated the days of the week in reverse order starting from Sunday. A high correlation was found between the DT tests and the balance tests. The TUG cognitive test had the lowest correlation with balance.
A possible reason why the dual-task tests are less related to balance is because they are considered difficult tests and the individual needs more time to perform them, probably because of cognitive impairment. Herman et al. [39] report that the decline in brain mass associated with aging, especially in the frontal lobe, leads to impaired cognitive processing abilities. These modifications restrict the brain’s ability to adapt and compensate for the movement and postural control challenges that come with aging, which explains the poorer performance in DT activities. In contrast, Goto et al. [40] suggest that structural or functional alterations in the brain may primarily explain the link between cognitive function and dynamic balance. Hippocampal volume plays a role in maintaining posture and balance [41]. Additionally, reduced gray matter volume has been linked to both cognitive deterioration and postural instability [42].
Functional muscle strength of the lower limbs appeared to have a negative inverse relationship with all TUG tests except the TUGMC test, where there was no relationship. The higher the participants′ scores on the 30-CST test, the shorter was the time required for the subjects to complete the TUG. The TUGME test had the highest correlation with muscle strength, but it was insignificant. The TUGVF test had the smallest correlation with muscle strength and was similar to the TUGMC. Hallal et al. [43], despite using a different methodology with a similar sample to the present study, found a correlation between muscle strength and the DT tests. The reason why the present study found little relationship between the TUG tests and muscle strength is probably because the 30-CST test is not as sensitive for community-dwelling older adults. This particular test involves a functional movement, leaning out of a chair, which is frequently performed in the daily life of this population, and this is probably the reason why all participants scored high. Assessing lower limb strength with more reliable and accurate tools for this population e.g., a dynamometer, would probably lead to different results.
No significant relationship was observed between balance confidence and the TUG tests. The questions included in the ABC scale describe activities of daily living, which are performed with particular ease in this population, hence the high scores noted. It is possible that by using a different questionnaire/scale with questions describing more difficult functional movements, different results for balance confidence or fear of falling would be noted compared to the performance of the TUG tests.

4.3. Limitations and Recommendations for Future Research

This study has several limitations. First, given the small sample size, the findings cannot be generalized to the entire elderly population. Furthermore, the sample consisted mainly of individuals who had no history of falls in the past year, making it impossible to correlate falls with the motor performance of each DT test. A second limitation is the lack of specific instructions for prioritizing the two tasks, which may have led to some participants focusing more on either the motor task or the cognitive task. Also, cognitive performance was not recorded under the simple activity condition or in the DT tests. Therefore, it was not possible to investigate changes in cognitive performance and the prioritization of the two tasks under the DT conditions. Third, only the cognitive tasks most used in DT gait assessments were investigated. It is not clear whether similar motor behavior would be observed with a secondary task that was either sensory or motor. Fourth, only the time taken to complete each TUG task was noted, without assessing other spatial and temporal parameters of gait, like number of steps or stride length. Although the TUG is easily administered in a clinical setting, this motor task only illustrates one parameter of motor ability, where only the change in completion time between the single test and the DT was analyzed.
A larger sample of different ages e.g., people over 80 years old, with or without cognitive impairment or with or without balance deficits should be included in future studies. It is crucial to investigate and compare the performance on the DT tests between male and female elderly people, and to investigate any gender differences in lower limb strength, dynamic balance, and balance confidence. Not only the type of cognitive task should be examined, but also the difficulty level of these tasks in the performance of walking with DT. The susceptibility of older individuals to different types of secondary tasks or to more challenging tasks has not been thoroughly explored. Also, further research with additional gait assessments will likely provide more information about older adults′ motor performance on the DT tests. Moreover, exploring the application of higher cognitive loads in motor tasks—such as through DT activities with virtual reality (VR) interventions—could be highly beneficial. VR, as demonstrated in previous studies [44], could yield intriguing results by providing immersive and adaptable environments for testing DT scenarios with real-world cognitive and motor challenges. Finally, it seems necessary to conduct a study of older people with a history of falls, not only to increase the sensitivity of the TUG test, for example by adding a cognitive load, but also to create new valid and reliable tests that can be easily applied in a clinical setting.

5. Conclusions

The present study showed that there was a greater decrease in motor performance relative to the simple TUG test when the TUG test with mental calculation and the TUG test with verbal fluency were performed simultaneously. In the mental calculation test, there was a slightly greater decrease in performance. In contrast, the simultaneous performance of the TUG test combined with a verbal reaction to an auditory stimulus was the easiest test, as there was little change in motor performance compared to the simple TUG test. Among the physical and psychological characteristics assessed, a relationship with the TUG tests was observed only with the variables of balance and strength, while no correlation was observed with the variable of balance confidence. Future studies with a larger sample, including a male population, should more effectively assess the performance of both motor and cognitive tasks. The addition of a cognitive load to the TUG test may enhance its ability to identify community-dwelling older adults who are at higher risk for falls by capturing the complex interplay between cognitive and motor functions. This approach may improve fall risk assessments and provide insights into how cognitive demands impact motor performance. As a result, it may serve as a valuable tool for developing targeted interventions that address both cognitive and motor challenges to better prevent falls.

Supplementary Materials

The following supporting information can be downloaded at: https://www.mdpi.com/article/10.3390/app14177957/s1, Table S1: Frequency distribution of demographic characteristics of the sample.

Author Contributions

Conceptualization, A.G., P.S. and A.C.; methodology, A.G., P.S. and A.C.; software, A.G. and P.S.; validation, E.L., D.C. and A.C.; formal analysis, A.G.; investigation, A.G. and P.S.; resources, A.G. and P.S.; data curation, A.G., P.S. and A.C.; writing—original draft preparation, A.G. and P.S.; writing—review and editing, A.C., E.L. and D.C.; visualization, A.G., P.S. and A.C.; supervision, A.C.; project administration, A.C. All authors have read and agreed to the published version of the manuscript.

Funding

This research received no external funding.

Institutional Review Board Statement

The study was conducted in accordance with the Declaration of Helsinki and approved by the Ethics Committee of the School of Health Studies of the University of Peloponnese (5365/11-03-2024).

Informed Consent Statement

Informed consent was obtained from all subjects involved in the study.

Data Availability Statement

Data available on request from the corresponding author due to privacy.

Acknowledgments

We would like to thank all the people who help us conduct the present study.

Conflicts of Interest

The authors declare no conflicts of interest.

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Applsci 14 07957 g001aApplsci 14 07957 g001b
Figure 1. Relationships between Timed Up and Go (TUG) test performance and (a) TUGME, (b) TUGMC, (c) TUGVF and (d) TUGRE performance.
Figure 1. Relationships between Timed Up and Go (TUG) test performance and (a) TUGME, (b) TUGMC, (c) TUGVF and (d) TUGRE performance.
Applsci 14 07957 g001aApplsci 14 07957 g001b
Table 1. Descriptive statistics of the demographic characteristics and the additional characteristics of the sample.
Table 1. Descriptive statistics of the demographic characteristics and the additional characteristics of the sample.
Sample CharacteristicsMeanStandard DeviationMinimum ValueMaximum Value
Age (y)72.225.116580
Hight (m)1.680.061.531.80
Weight (kg)69.878.6349.2090.20
BMI (kg/m2)24.602.082030.70
MMSE28.381.192530
30-CST (number of chair raises)10.581.01912
FSST (s)12.011.519.0015.06
ABC (%)87.877.7360.6298.75
Abbreviations: BMI: Body Mass Index; MMSE: Mini Mental State Examination; 30-CST: 30-Second Chair Stand Test; FSST: Four Square Step Test; ABC: Activities-Specific Balance Confidence scale.
Table 2. Mean values and standard deviations of TUG and DTCs variables.
Table 2. Mean values and standard deviations of TUG and DTCs variables.
VariableMeanStandard DeviationMinimum ValueMaximum Value
TUG (s)10.321.167.8112.21
TUGME (s)12.591.869.0018.39
TUGMC (s)14.302.639.3021.36
TUGVF (s)13.672.429.8519.98
TUGRE (s)11.251.427.9014.65
DTCME (%)−20.7010.48−46.84−2.38
DTCMC (%)−37.2619.19−79.97−4.72
DTCVF (%)−30.4417.43−70.48−2.98
DTCRE (%)−7.916.26−27.70−0.27
Abbreviations: TUG: Timed Up and Go; TUGME: memory Timed Up and Go test; TUGMC: mental calculation Timed Up and Go test; TUGVF: verbal fluency Timed Up and Go test; TUGRE: reaction Timed Up and Go test; DTCME: Dual-task cost (memory test); DTCMC: Dual-task cost (mental calculation test); DTCVF: Dual-task cost (verbal fluency test); DTCRE: Dual-task cost (reaction test).
Table 3. Descriptive statistics and differences between measures of muscle strength (30-CST), dynamic balance (FSST), balance confidence (ABC), the Timed Up and Go (TUG) tests performance and the Dual-task costs (DTCs) using paired t-tests.
Table 3. Descriptive statistics and differences between measures of muscle strength (30-CST), dynamic balance (FSST), balance confidence (ABC), the Timed Up and Go (TUG) tests performance and the Dual-task costs (DTCs) using paired t-tests.
VariablesMeanStandard Deviationt
30-CST–FSST−1.432.28−4.87 **
30-CST–ABC−77.287.42−80.60 **
FSST–ABC−75.858.38−70.07 **
TUG–TUGME−2.271.21−14.42 **
TUG–TUGMC−3.972.09−14.69 **
TUG–TUGVF−3.351.89−13.72 **
TUG–TUGRE−0.920.67−0.75 **
DTCME–DTCMC16.5618.646.88 **
DTCME–DTCVF9.7416.644.53 **
DTCME–DTCRE−12.7810.46−9.46 **
DTCMC–DTCVF−6.8212.10−4.36 **
DTCMC–DTCRE−29.3418.05−12.59 **
DTCVF–DTCRE−22.5215.96−10.92 **
Abbreviations: 30-CST: 30-Second Chair Stand Test; FSST: Four Square Step Test; ABC: Activities-Specific Balance Confidence scale; TUG: Timed Up and Go; TUGME: memory Timed Up and Go test; TUGMC: mental calculation Timed Up and Go test; TUGVF: verbal fluency Timed Up and Go test; TUGRE: reaction Timed Up and Go test; DTCME: Dual-task cost (memory test); DTCMC: Dual-task cost (mental calculation test); DTCVF: Dual-task cost (verbal fluency test); DTCRE: Dual-task cost (reaction test) ** p < 0.001.
Table 4. Pearson’s r correlations between the Timed Up and Go (TUG) test performance and the four dual-task TUG tests (TUGME, TUGMC, TUGVF, TUGRE) performance.
Table 4. Pearson’s r correlations between the Timed Up and Go (TUG) test performance and the four dual-task TUG tests (TUGME, TUGMC, TUGVF, TUGRE) performance.
VariablesTUGMETUGMCTUGVFTUGRE
TUG0.77 **0.63 **0.65 **0.89 **
Abbreviations: TUG: Timed Up and Go; TUGME: memory Timed Up and Go test; TUGMC: mental calculation Timed Up and Go test; TUGVF: verbal fluency Timed Up and Go test; TUGRE: reaction Timed Up and Go test ** p < 0.01.
Table 5. Pearson’s r correlations between the Timed Up and Go (TUG) tests performance and measures of muscle strength (30-CST), dynamic balance (FSST), and balance confidence (ABC).
Table 5. Pearson’s r correlations between the Timed Up and Go (TUG) tests performance and measures of muscle strength (30-CST), dynamic balance (FSST), and balance confidence (ABC).
Variables30-CSTFSSTABC
TUG−0.24 *0.48 **−0.12
TUGME−0.34 **0.46 **−0.16
TUGMC−0.230.28 *−0.14
TUGVF−0.29 *0.32 *−0.08
TUGRE−0.28 *0.41 **−0.22
Abbreviations: TUG: Timed Up and Go; TUGME: memory Timed Up and Go test; TUGMC: mental calculation Timed Up and Go test; TUGVF: verbal fluency Timed Up and Go test; TUGRE: reaction Timed Up and Go test; 30-CST: 30-S Chair Stand Test; FSST: Four Square Step Test; ABC: Activities-Specific Balance Confidence scale ** p < 0.01, * p < 0.05.
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Georgantas, A.; Stefani, P.; Lyros, E.; Chytas, D.; Christakou, A. Examining Performance between Different Cognitive-Motor Dual-Task Tests in Community-Dwelling Older Adults. Appl. Sci. 2024, 14, 7957. https://doi.org/10.3390/app14177957

AMA Style

Georgantas A, Stefani P, Lyros E, Chytas D, Christakou A. Examining Performance between Different Cognitive-Motor Dual-Task Tests in Community-Dwelling Older Adults. Applied Sciences. 2024; 14(17):7957. https://doi.org/10.3390/app14177957

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Georgantas, Anastasios, Panagiota Stefani, Epameinondas Lyros, Dimitrios Chytas, and Anna Christakou. 2024. "Examining Performance between Different Cognitive-Motor Dual-Task Tests in Community-Dwelling Older Adults" Applied Sciences 14, no. 17: 7957. https://doi.org/10.3390/app14177957

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