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Introduction: The association between specific motor capacity variables obtained in a laboratory and parameters of daily-life mobility performance (MP) obtained via wearables is still unclear. The Timed Up-and-Go (TUG) test is a widely used motor capacity tests available either as traditional hand-stopped TUG or as instrumented TUG (iTUG), providing specific information about its subphases. This study aimed to: (1) estimate the association between the TUG and specific parameters reflecting average and maximum daily-life MP, (2) estimate the benefits of the iTUG in terms of explaining MP in daily life compared to the TUG. Methods: The present study was a cross-sectional analysis using baseline data of 294 older persons (mean age: 76.7 ± 5.3 years). Univariate linear regression analysis was performed to delineate the coefficient of determination between TUG time and participants' MP. MP variables containing mean cadence (MCA) to represent average performance and the 95th percentile of mean cadence of walks with more than three steps (p95>3stepsMCA) to represent maximum performance. To determine whether the iTUG variables give more information about MP, a stepwise multivariate regression analysis between iTUG variables and the p95>3stepsMCA variable to represent maximum performance was conducted. Results: The univariate regression models revealed associations of the TUG with MCA (adjusted R2 = 0.078, p < 0.001) and p95>3stepsMCA (adjusted R2 = 0.199, p < 0.001). The multivariate stepwise regression models revealed a total explanation of maximum daily-life MP (p95>3stepsMCA) of the TUG (adjusted R2 = 0.199, p < 0.001) versus iTUG (adjusted R2 = 0.278, p < 0.010). Discussion/Conclusion: This study shows that the TUG better reflects maximum daily-life MP than average daily-life MP. Moreover, we demonstrate the added value of the iTUG for a more accurate estimation of daily MP compared to the traditional TUG. The iTUG is recommended to estimate maximum daily-life MP in fall-prone older adults. The study is a step toward a specific assessment paradigm using capacity variables from the iTUG to estimate maximum daily-life MP. [ABSTRACT FROM AUTHOR]

Studies on the effects of aging on cognition have been using the same cognitive tests for decades. A Wireless Lighting System (WLS) could be used to assess cognitive functions in a physically active situation, making the assessment of cognition less isolated and more ecological. This pilot study aimed to evaluate the potential of a WLS for assessing older adults' cognitive functions. It was set up with 15 young (M = 23.47 years old) and 18 older adults (M = 71.44 years old). Their performances were recorded on three WLS tests, designed with the Witty SEM system to assess four main cognitive functions (i.e., inhibition, flexibility, visuospatial short-term and working memory), as well as on three traditional (TRAD) tests (Spatial Span Test, Stroop Test, Trail Making Test). The results show a significant difference between the YOUNG and OLD groups on all WLS test measures (except for WLS flexibility), as well as on all TRAD measures. Additionally, for the OLD group, there were significant correlations between WLS and TRAD test results (r = −0.49 for two measures of inhibition to r = −0.80 for two other measures of inhibition), except for visuospatial short-term memory. However, there was no significant correlation for the YOUNG group (ρ = −0.27 for inhibition to r = 0.45 for visuospatial short-term memory). These WLS tests were valid for assessing the cognitive functions (i.e., flexibility, visuospatial short-term and working memory, inhibition) of older adults and were sensitive to aging. [ABSTRACT FROM AUTHOR]

Background and Purpose: Older adults with lower balance confidence demonstrate a reduced willingness to experience instability as the task of walking becomes more challenging (i.e., walking with a faster speed). However, the specific reason why is not known. The purpose of this study was to investigate the extent to which capacity of increasing walking speeds relates to the attentional requirements (i.e., automaticity) of walking. Methods: Sixteen young (31 ± 5.85 years) and 15 older participants (69 ± 3.04 years) began walking on a treadmill at 0.4 m/s, and speed was increased by 0.2 m/s until the participant either chose to stop or reached a speed of 2.0 m/s. Sixty steps were collected at steady-state speed for each walking trial. Kinematic data were collected, and the margin of stability in the anterior direction (MOSAP) at heelstrike was quantified for each step. The timed up and go (TUG) and TUG dual (TUGdual) task were performed, from which an automaticity index (TUG/TUGdual × 100) was calculated. Older individuals were grouped based on whether they did or did not complete all walking speeds (i.e., completers [n = 9] or noncompleters [n = 6]). The fastest walking speed attempted (FSA), automaticity index, and MOSAP were compared, and correlations were assessed between the FSA/MOSAP and the automaticity index. Results: A significant difference was identified in an average MOSAP at heelstrike between older completer and noncompleter groups (p < 0.001). Further, older adults with lower automaticity index choose to stop walking at lower speeds (p = 0.001). The FSA was positively correlated with the automaticity index (ρ = 0.81, p < 0.001). Finally, the average MOSAP at FSA and the automaticity index were also negatively correlated (r = −0.85, p < 0.001). Conclusion: Older adults with lower automaticity of walking choose to stop walking at speeds before they completed all walking speeds, which may relate with increased attentional demands required to maintain dynamic stability at higher walking speeds. Given that these were otherwise healthy adults, the combination of FSA and an automaticity of walking may help to identify individuals who should be considered for an assessment to identify walking problems. [ABSTRACT FROM AUTHOR]

Introduction: Preoperative frailty is an independent risk factor for postoperative complications across surgical specialties. Functional mobility such as gait, timed up and go (TUG), and 5 times sit-to-stand (5-STS) are popular preoperative frailty measurements but are not suitable for patients with severe mobility impairment. A wrist-worn sensor-derived frailty index based on an upper-extremity functional test (20-s repetitive elbow flexion-extension task; UEFI) was developed previously; however, its association with functional mobility remained unexplored. We aimed to investigate the predictive power of the UEFI in predicting functional mobility. Methods: We examined correlation between the UEFI and gait speed, TUG duration, and 5-STS duration in 100 older adults (≥ 65 years) using multivariate regression analysis. The UEFI was calculated using slowness, weakness, exhaustion, and flexibility of the sensor-based 20-s repetitive elbow flexion-extension task. Results: The UEFI was a significant predictor for gait speed and TUG duration and 5-STS duration (all R ≥ 0.60; all p < 0.001) with the variance (adjusted R2) of 35–37% for the dependent variables. The multivariate regression analysis revealed significant associations between the UEFI and gait speed (β = −0.84; 95% confidence interval [95% CI] = [−1.19, −0.50]; p < 0.001) and TUG duration (β = 16.2; 95% CI = [9.59, 22.8]; p < 0.001) and 5-STS duration (β = 33.3; 95% CI = [23.6, 43.2]; p < 0.001), found after accounting for confounding variables (e.g., age and fear of falling scale). Conclusions: Our findings suggest that the UEFI can be performed with a wrist-worn sensor and has been validated with other established measures of preoperative frailty. The UEFI can be applied in a wide variety of patients, regardless of mobility limitations, in an outpatient setting. [ABSTRACT FROM AUTHOR]

Background: In older adults, the linkage between laboratory-assessed 'motor capacity' and 'mobility performance' during daily routine is controversial. Understanding factors moderating this relationship could help developing more valid assessment as well as intervention approaches. We investigated whether the association between capacity and performance becomes evident with transition into frailty, that is, whether frailty status moderates their association. Methods: We conducted a cross-sectional analysis of the observational (blinded for review) study in a community-dwelling cohort in (blinded for review). Participants were N = 112 older adults aged 65 years or older who were categorized as non-frail (n = 40), pre-frail (n = 53) or frail (n = 19) based on the Fried frailty index. Motor capacity was quantified as normal (NWS) and fast walking speed (FWS). Mobility performance was quantified as 1) cumulated physical activity (PA) time and 2) everyday walking performance (average steps per walking bout; maximal number of steps in one walking bout), measured by a motion sensor over a 48 h period. Hierarchical linear regression analyses were performed to evaluate moderation effects. Results: Unlike in non-frail persons, the relationship between motor capacity and mobility performance was evident in pre-frail and frail persons, confirming our hypothesis. A moderating effect of frailty status was found for 1) the relationship between both NWS and FWS and maximal number of steps in one bout and 2) NWS and the average steps per bout. No moderation was found for the association between NWS and FWS with cumulated PA. Conclusion: In pre-frail and frail persons, motor capacity is associated with everyday walking performance, indicating that functional capacity seems to better represent mobility performance in this impaired population. The limited relationship found in non-frail persons suggests that other factors account for their mobility performance. Our findings may help to inform tailored assessment approaches and interventions taking into consideration a person's frailty status. [ABSTRACT FROM AUTHOR]