Gait characteristics associated with walking speed decline in older adults: results from the Baltimore Longitudinal Study of Aging

High cadence cycling not high work rate, increases gait velocity post-exercise

Gait velocity, or walking speed, has been referred to as the sixth vital sign, and research suggests that it is highly sensitive to change. Previous research has demonstrated the utility of cycling to improve gait parameters and in particular gait velocity in a variety of populations. However, it is unclear if the benefits from cycling to gait velocity stem from increased cadence, increased work rate, or the interaction between them. Therefore, the objective of the current research was to explicitly test the relationship between cycling work rate, cycling cadence, and gait velocity. 45 recreationally active young adults were randomly assigned to cycle at a normalised cadence and work rate, a higher cadence, or a higher work rate (CONTROL, FAST, HARD). All participants completed two ten-metre walk tests (10 MWT) pre- and post-cycling intervention. There was a significant interaction between group and time and post hoc comparisons showed that the FAST group walked significantly faster than the HARD group post-cycling. These results support the hypothesis that cycling at a cadence greater than the comfortable walking cadence, and not cycling at an increased work rate, increased gait velocity post-exercise for all members of our sample of healthy young adults.

Exploring new balance and gait factors that are associated with osteosarcopenia in patients with a previous fall and/or fracture history

Osteosarcopenic individuals have poor muscle function and increased bone fragility, which results in a severe detriment to health outcomes. Hence, there is a necessity to discover easily accessible factors associated with osteosarcopenia to develop timely interventions. This study aimed to determine new sensitive balance and/or gait variables that are associated with osteosarcopenia in a population of older people with a history of falls and/or fractures. In a cross-sectional cohort study, 306 men and women aged ≥65 years completed a series of questionnaires, clinical assessments and muscle strength and function tests. Subsequently, participants were separated into osteopenia, osteoporosis and osteosarcopenia, groups for comparison and further analysis. Osteosarcopenia performed worse than osteopenia and osteoporosis in grip strength, gait speed, physical function scores and in multiple gait and balance indices (p<0.001). During posturography testing, there were larger elliptical areas with eyes open (p = 0.003), and eyes closed (p = 0.043) and increased sway velocity on a firm platform (p = 0.007) in the osteosarcopenia group, compared to osteoporosis. Limits of stability and eyes open ellipse area significantly contributed to the multivariable model (p = 0.029 and p = 0.038, respectively), suggesting that these balance parameters, along with grip strength, may be useful in identifying older adults with osteosarcopenia from those with only osteopenia/osteoporosis. Older adults with osteosarcopenia and a history of falls and/or fractures demonstrated inferior strength, function, and gait characteristics. This study identified indices of balance that were sensitive discriminators for osteosarcopenia and could be easily implemented into routine assessment.

A full-body motion capture gait dataset of 138 able-bodied adults across the life span and 50 stroke survivors

This reference dataset contains biomechanical data of 138 able-bodied adults (21-86 years) and 50 stroke survivors walking bare-footed at their preferred speed. It is unique due to its size, and population, including adults across the life-span and over 70 years, as well as stroke survivors. Full-body kinematics (PiG-model), kinetics and muscle activity of 14 back and lower limbs muscles was collected with a Vicon motion capture system, ground-embedded force plates, and a synchronized surface EMG system. The data is reliable to compare within and between groups as the same methodology and infrastructure were used to gather all data. Both source files (C3D) and post-processed ready-to-use stride-normalized kinematics, kinetics and EMG data (MAT-file, Excel file) are available, allowing high flexibility and accessibility of analysis for both researchers and clinicians. These records are valuable to examine ageing, typical and hemiplegic gait, while also offering a wide range of reference data which can be utilized for age-matched controls during normal walking.

Normative reference values, determinants and regression equations for the incremental shuttle walk test (ISWT) in healthy Asian population aged 21 to 80 years

BACKGROUND

The validated Incremental Shuttle Walk Test (ISWT) is widely used for evaluating maximal exercise capacity, with the distance-walked (IWSD) as the primary outcome. However, there are no normative reference values (NRV) and reference equations to predict ISWD for the Singaporean population.

OBJECTIVES

This study aims to establish the NRV and reference equations for ISWD in healthy Singaporeans aged 21 to 80 and investigate the determining variables during ISWT.

METHODS

This cross-sectional study recruited community-dwelling healthy subjects aged 21-80 from the community via convenience sampling. Each subject completed two trials of the ISWT according to the standard protocol. Variables measured during the trials included ISWD, pre-and post-test heart rate (HR), oxygen saturation, blood pressure (BP), modified Borg's dyspnoea score and Borg's rate of perceived exertion (RPE).

RESULTS

199 healthy Singaporean (females = 114, males = 85) participated in the study. The overall median ISWD was 660.0 metres (m) [interquartile range (IQR):440.0-850.0]. The age-stratified mean ISWD ranged from 430.0 m (IQR:350.0-450.0) (aged 60-80) to 480.0 m (IQR:438.0-650.0) (aged 40-59) to 780.0 m (IQR:670.0-960.0) (aged 21-39). Gender, age, weight, height and HR change (highest post-test HR minus pre-test HR) were the most significant variables (p < 0.001). IWSD (m) = 651.4(Height, m) +89.7(Gender, male = 1; female = 0) -6.31(Age, years) -3.61(Weight, kilograms) +2.54(HR change, beats per minute); R2 = 0.741. Previously published ISWT reference equations cannot accurately predict the ISWD in the Singaporean population.

CONCLUSIONS

This study investigated the ISWD NRV and established reference equations for healthy Singaporeans aged 21-80. The information would be beneficial in setting performance benchmarks to guide physical assessment, intervention and rehabilitation.

Influence of transcutaneous electrical nerve stimulation on walking kinematics and standing balance of older adults who differ in walking speed

The purpose was to determine the impact of transcutaneous electrical nerve stimulation (TENS) on measures of walking kinematics and standing balance of healthy older adults who were stratified into two groups based on differences in the distance walked during the 6-min test of walking endurance. Regression models were developed to explain the variance in the 6-min distance and to assess the predictive power of balance metrics to categorize the 26 older adults (72 ± 5.4 yrs) as either slow or fast walkers. Walking kinematics were measured during 6- and 2-min walk tests that were performed with and without the concurrent application of TENS to the hip flexor and ankle dorsiflexor muscles. Participants walked briskly during the 6-min test and at a preferred pace during the 2-min test. The supplementary sensory stimulation provided by TENS did not alter the power of the models to explain the variance in the Baseline 6-min distance: Baseline, R² = 0.85; TENS, R² = 0.83. In contrast, TENS improved the explanatory power of the data obtained during the 2-min walk to account for the variance in the Baseline 6-min distance: no TENS, R² = 0.40; TENS, R² = 0.64. Logistic regression models based on force-plate and kinematic data obtained during the balance tasks were able to discriminate between the two groups with excellent certainty. The impact of TENS was greatest when older adults walked at a preferred speed but not when they walked at a brisk pace or performed tests of standing balance.

Low Correlation between Gait and Quality of Life in Advanced Knee Osteoarthritis

Advanced knee osteoarthritis patients' gait usually undergoes alterations leading to decreased mobility and lower functional performance, which can result in a worsening of their quality of life (QoL). While several authors have reported a moderate correlation between gait parameters and QoL assessed by generic questionnaires, the literature is scarce. This study aimed to explore the relationship between gait and QoL parameters assessed by a generic and a disease-specific questionnaire in patients with advanced knee osteoarthritis. In this single-centre, prospective, observational study, 129 patients with advanced knee osteoarthritis scheduled for elective total knee replacement were selected. The patients' gait was evaluated by means of a validated wireless device while they walked 30 m at a comfortable speed. Patient function was also analysed using the Knee Society Score (KSS). QoL was measured with the EQ-5D and the Knee Injury and Osteoarthritis Outcome Score (KOOS) questionnaires. Patients showed a mean walking speed of 0.95 ± 0.19 m/s, a mean cadence of 105.6 ± 9.9 steps/min, and a mean stride length of 1.25 ± 0.17 m on both legs. They presented poor knee status (KSS < 60) and poor QoL, with an EQ-5D of 0.44 ± 0.24 and a total KOOS of 29.77 ± 13.99. Positive low correlations (r <0.5, p <0.5) were found only between the speed, propulsion and stride length of both legs, and the overall and ADLs subscale scores of the total KOOS questionnaire. In conclusion, several gait parameters have a significant low correlation with the QoL of patients with advanced knee osteoarthritis, as assessed by an osteoarthritis-specific questionnaire.

Free-Living Gait Cadence Measured by Wearable Accelerometer: A Promising Alternative to Traditional Measures of Mobility for Assessing Fall Risk

BACKGROUND

Wearable devices have become widespread in research applications, yet evidence on whether they are superior to structured clinic-based assessments is sparse. In this manuscript, we compare traditional, laboratory-based metrics of mobility with a novel accelerometry-based measure of free-living gait cadence for predicting fall rates.

METHODS

Using negative binomial regression, we compared traditional in-clinic measures of mobility (6-minute gait cadence, speed, and distance, and 4-m gait speed) with free-living gait cadence from wearable accelerometers in predicting fall rates. Accelerometry data were collected with wrist-worn Actigraphs (GT9X) over 7 days in 432 community-dwelling older adults (aged 77.29 ± 5.46 years, 59.1% men, 80.2% White) participating in the Study to Understand Fall Reduction and Vitamin D in You. Falls were ascertained using monthly calendars, quarterly contacts, and ad hoc telephone reports. Accelerometry-based free-living gait cadence was estimated with the Adaptive Empirical Pattern Transformation algorithm.

RESULTS

Across all participants, free-living cadence was significantly related to fall rates; every 10 steps per minute higher cadence was associated with a 13.2% lower fall rate (p = .036). Clinic-based measures of mobility were not related to falls (p > .05). Among higher-functioning participants (cadence ≥100 steps/minute), every 10 steps per minute higher free-living cadence was associated with a 27.7% lower fall rate (p = .01). In participants with slow baseline gait (gait speed <0.8 m/s), all metrics were significantly associated with fall rates.

CONCLUSION

Data collected from biosensors in the free-living environment may provide a more sensitive indicator of fall risk than in-clinic tests, especially among higher-functioning older adults who may be more responsive to intervention.

CLINICAL TRIAL REGISTRATION

NCT02166333.

Walk Smarter, Not Harder: Effects of Cadence Manipulation on Gait Biomechanics in Patients with Patellofemoral Osteoarthritis

PURPOSE

This study aimed to investigate the effect of walking cadence on knee flexion angular impulse and peak external flexion moment in patients with patellofemoral osteoarthritis (OA).

METHODS

Forty-eight patients with patellofemoral OA underwent repeated quantitative gait analyses on an instrumented treadmill using a randomized crossover design. Walking trials were conducted at a fixed gait speed, under three cadence conditions: (i) preferred cadence, (ii) +10% increased cadence, and (iii) -10% decreased cadence, completed in random order. Using a linear mixed model, we tested the association of cadence conditions with surrogate measures of patellofemoral load (primary outcome measure: knee flexion angular impulse) while controlling for body mass. We then repeated the analyses while sequentially replacing the dependent variable with secondary outcome measures.

RESULTS

Walking with increased cadence decreased (adjusted mean difference [95% confidence interval]) the knee flexion angular impulse (-0.85 N·m·s -1 [-1.52 to -0.18], d = 0.20) and peak knee flexion moment (-4.11 N·m [-7.35 to -0.86], d = 0.24), whereas walking with decreased cadence increased the knee flexion angular impulse (1.83 N·m·s -1 [1.15 to 2.49], d = 0.42) and peak knee flexion moment (3.55 N·m [0.30 to 6.78], d = 0.21). Similar decreases and increases were observed for secondary outcome measures.

CONCLUSIONS

Walking with increased cadence, while maintaining a fixed gait speed, reduces knee flexion angular impulse as well as other surrogate measures of knee loading in patients with patellofemoral OA.

Are Age, Self-Selected Walking Speed, or Propulsion Force Predictors of Gait-Related Changes in Older Adults?

There is limited research that directly compares the effect of reduced speed with reduced propulsive force production (PFP) on age-related gait changes. We aimed to determine how changes in the gait of older adults correlate with age, speed, or peak PFP over a 6-year span. We collected kinematics and kinetics of 17 older subjects at 2 time points. We determined which biomechanical variables changed significantly between visits and used linear regressions to determine whether combinations of self-selected walking speed, peak PFP, and age correlated to changes in these variables. We found a suite of gait-related changes that occurred in the 6-year period, in line with previous aging studies. Of the 10 significant changes, we found 2 with significant regressions. Self-selected walking speed was a significant indicator of step length, not peak PFP or age. Peak PFP was a significant indicator for knee flexion. None of the biomechanical changes were correlated to the chronological age of the subjects. Few gait parameters had a correlation to the independent variables, suggesting that changes in gait mechanics were not solely correlated to peak PFP, speed, and/or age. This study improves understanding of changes in ambulation that lead to age-related gait modifications.

Steps parameters of elderly patients hospitalised for an acute medical illness in a Swiss University Hospital: a monocentric observational pilot-study

BACKGROUND

Objective mobility goals for elderly hospitalised medical patients remain debated. We therefore studied steps parameters of elderly patients hospitalised for an acute illness, to determine goals for future interventional trials and medical practice.

METHODS

Observational study conducted from February to November 2018 in a medical ward of the Lausanne University Hospital, Switzerland. We measured the step parameters of consecutive medical patients aged ≥65 years admitted for an acute medical illness using a wrist accelerometer (Geneactiv). We also collected demographic, somatic and functional factors.

RESULTS

Overall, 187 inpatients had their step parameters (daily step count, walking cadence and bout duration) measured with accelerometers worn for a mean of 3.6 days (standard deviation [SD] 3.2). Elderly inpatients (81.5 years, SD 8.5) walked a median of 603 steps daily (interquartile range [IQR] 456-809), at a median cadence of 100 steps/minute (IQR 99-101) with median walking bouts of 33 seconds (IQR 27-37) and with 70% of the walking bouts lasting less than 30 seconds. Patients walking ≥600 steps were younger (80.4 years, SD 8.9 vs 82.8 years,SD 7.9, p = 0.050) and had a longer length of stay (7.8 days, SD 5.1 vs 6.1 days, SD 4.1, p = 0.011) than those walking <600 steps. Patients at high risk of bed sores walked less (564 steps, IQR 394-814 vs 626, IQR 526-840) than those with a lower risk of sores.

CONCLUSION

During a hospitalisation for an acute medical illness, patients aged ≥65 years walk a mere 603 steps daily and most of the time for periods of less than 30 seconds. This information should be used to build up future interventional trials or to set mobility goals for patients hospitalised in Swiss hospitals.

Determination of the Predictors with the Greatest Influence on Walking in the Elderly

Background and Objectives: Previous studies have revealed that independent variables (lower extremity strength, postural control ability, and body composition) influence gait performance and variability, but the difference in the relative influence between these variables is unclear. Hence, this study determines the variable that is the most influential predictor of gait performance and variability among potential independent variables in the elderly. Materials and Methods: Seventy-eight subjects aged ≥60 years participated. For each subject, the gait variables and lower extremity muscle strength were measured using an accelerometer worn on both feet during a 6-minute walk and a manual force sensor, respectively. The static balance ability was measured through two force plates, and the body composition was measured by applying bioelectrical impedance analysis. Linear regression analyses were performed stepwise to determine whether these variables affect gait performance and variability. Results: After adjusting for sex and gait performance, the ankle strength, body fat mass, mean velocity in the medial-lateral direction, ankle plantar flexion strength, and girth were predictors of gait speed dorsiflexion, gait performance, swing width of the gait performance, walking speed, and gait variability, respectively. Conclusions: Overall, gait performance in the elderly is related to muscle strength, postural control, and body composition in a complex manner, but gait variability appears to be more closely related to ankle muscle strength. This study provides further evidence that muscle strength is important in motor function and stability.

The Role of Physical Function in the Association between Physical Activity and Gait Speed in Older Adults: A Mediation Analysis

Adequate levels of physical function (PF) are essential for vulnerable older adults to perform their daily tasks safely and remain autonomous. Our objective was to explore the mediating role of PF in the relationship between physical activity (PA) and gait speed (GS) in a large sample of older adults from the north of Brazil. This is a cross-sectional study that analyzed 697 older adults (mean age 70.35 ± 6.86 years) who participated in the project "Health, Lifestyle, and Physical Fitness in Older Adults in Amazonas" (SEVAAI). PA was assessed using the Baecke Questionnaire, PF using the Senior Fitness Test, and GS using the 50-foot Walk Test. Mediation pathways were analyzed to test the possible mediating role of PF between specific PA domains (PA-total score, PA-housework, PA-sport, PA-leisure) and GS. Regarding PA-total, the analysis showed that high-performance GS was partially mediated in approximately 19% by better PF performance. Moreover, the PF could partially mediate the association between PA-sport and PA-leisure with GS, at levels of approximately 9% and 46%, respectively. An inverse relationship was observed between PA-housework (sedentary lifestyle) and GS. This association was partially mediated to an extent of approximately 9% by better PF performance. We conclude that PF plays a crucial role in mediating the association between PA and GS among vulnerable older adults.

The Toronto Concussion Study: Reference Data for Balance and Gait Measures in Community-Dwelling Adults With Concussion

OBJECTIVE

Concussion can cause deficits in balance and gait. Much of what is known about how concussion affects balance and gait has been derived from studies involving youth, high school, and university athletes. However, investigation into the effects of concussion on balance and gait in community-dwelling young, middle-age, and older aged adults is limited. This study aimed to present descriptive reference values for common balance and gait measures in community-dwelling adults between the ages of 20 and 69 years with concussion.

METHODS

In this observational study, 318 participants were enrolled from a concussion care clinic at a rehabilitation hospital in an urban center and were assessed within 7 days of injury. Balance measures included the Balance Error Scoring System (BESS), modified BESS, and center-of-pressure root mean square during quiet standing. Gait measures included velocity (absolute and height adjusted), cadence, and step length during self-paced gait. Data were binned by decade-long age range.

RESULTS

Mean (SD) per-decade scores for the BESS ranged from 14.8 (5.1) to 21.8 (5.6) errors and 4.0 (3.0) to 9.4 (4.6) errors for the modified BESS. Mean values for center-of-pressure root mean square in the anteroposterior direction ranged from 0.42 (0.18) to 0.52 (0.26) with the eyes open, and from 0.49 (0.19) to 0.62 (0.39) with eyes closed. Mean absolute gait velocity ranged from 98.5 (9.1) to 119.3 (21.3) cm/s. The range of step length values was 58.2 (6.8) to 66.3 (7.3) cm and cadence ranged from 102.1 (9.8) to 108.6 (10.8) steps/min across age groups.

CONCLUSION

These data provide insight into the impact of concussion on balance and mobility in community-dwelling adults across the lifespan.

IMPACT

Community-dwelling adults can experience concussion across the lifespan. Availability of reference values for commonly used balance and gait measures can help to inform clinical strategies and progression of recovery of balance and mobility after injury.

Natural aging course of lumbar extensor muscle mass and strength in community-dwelling older women: a 1-year prospective observational study

BACKGROUND

Although the loss of skeletal limb muscle mass and muscle strength in the elderly have been demonstrated, the aging process of the back muscles to maintain core stability is not well known. This 1-year prospective observational study aimed to investigate the natural aging course of the lumbar extensor muscles (LEMs) compared with the extremity muscles and determine whether muscle strength or mass decreases more in community-dwelling older women.

METHODS

Twenty-four older urban-dwelling women aged 70 years or older were initially enrolled. Their demographic variables, conventional and spinal sarcopenia indices, and functional outcome parameters were evaluated. We also measured back extensor strength, radiological parameters for spinal sagittal balance on whole-spine radiography, and volumetric parameters of the LEM on computed tomography.

RESULTS

After the exclusion of 6 subjects, 18 older women were finally analyzed. All variables related to extremity muscle mass, muscle strength, physical performance, and LEM volume declined over the study period, but the changes were insignificant. However, back extensor strength decreased significantly (median, first, and third quartile: 35.20 [30.80, 44.00] N to 31.40 [29.25, 37.90] N, P = 0.026). Among spinal sagittal balance-related parameters, lumbar lordosis (44.25 [39.30, 47.35]° to 43.15 [31.43, 45.75]°, P = 0.043) and sagittal vertical axis (33.85 [3.57, 58.75] mm to 45.15 [25.35, 58.68] mm, P = 0.004) showed significant changes during the study.

CONCLUSIONS

When the natural aging course of LEM in women aged 70 years or older was observed for 1 year, muscle mass decreased less than back extensor strength and spinal sagittal balance. Measurements of back extensor strength and spinal sagittal balance are necessary for the clinical evaluation of spinal aging.

Association among cognitive function, physical fitness, and health status in older women

This study examined the association among cognitive function, physical fitness, and health status in healthy older women. Ninety-four females aged from 62 to 86 years (72.66±5.38 years) from community healthcare centers and an exercise club in Seoul, South Korea. Cognitive function was assessed using the Seoul Neuropsychological Screening Battery. Physical performance comprised cardiorespiratory endurance, lower extremity strength, active balance ability, and walking speed. Health status included blood pressure and waist circumference. Multiple linear regression analyses were performed to determine the relationship among cognitive function, fitness components, and health status, with age and educational attainment as covariates. In the unadjusted model, attention was significantly associated with cardiovascular endurance (B=0.19, P<0.05). Memory was significantly associated with lower limb strength (B=0.77, P<0.05) and active balance ability (B=2.35, P<0.05). In the adjusted model, attention was significantly associated with cardiovascular endurance (B=0.15, P<0.05). Memory was significantly associated with lower limb strength (B=0.87, P<0.05). In both models, cognitive function was not significantly associated with any health status variable. Though limited by a relatively small sample of female participants, who were healthy registrants of a community exercise program with normal cognitive function, the current study demonstrates that cognitive function is significantly associated with physical fitness, but not with health status, in healthy older women.

Influencing factors for the decline of limb muscle strength and the association with all-cause mortality: evidence from a nationwide population-based cohort study

BACKGROUND

The decline of muscle strength, a typical characteristic of sarcopenia, greatly affects aging-related health outcomes; however, prospective data on influencing factors and mortality in the Chinese population are relatively sparse.

AIMS

We investigated the influencing factors for the declined limb muscle strength and the association with all-cause mortality among the elderly Chinese individuals aged ≥ 65 years in a large long-term prospective cohort study.

METHODS

We used data from the China Health and Retirement Longitudinal Study (CHARLS). Logistic regression analyses were performed to investigate the influencing factors of declined limb muscle strength. Cox proportional hazard models were used to analyze the impact on all-cause mortality, whose performance was evaluated by train-test cross-validation.

RESULTS

The prevalences of declined upper and lower limb strength, which were defined by low hand grip strength (HS) and gait speed (GS), respectively, were 34.4% and 59.7%. The declined HS was significantly associated with older age (p < 0.001), female (p < 0.001), lower educational level (p < 0.001), lower BMI (p < 0.001), and combined with chronic diseases (p = 0.001). Moreover, the declined limb muscle strength was correlated with all-cause mortality (HR: 1.13, 95% CI 1.03-1.21 for HS; HR: 1.09, 95% CI 1.04-1.15 for GS), according to a multi-adjusted model with moderate predictive ability (C-index: 0.714, AUC of 7 year follow-up: 0.716).

CONCLUSIONS

The decline of limb muscle strength was prevalent among elderly Chinese individuals and had a strong impact on all-cause mortality. Identification of key populations and tailored interventions on their influencing factors should be implemented in further research.

Longitudinal effects of physical exercise on health-related outcomes based on frailty status in community-dwelling older adults

AIM

To clarify the difference in the longitudinal effects of physical exercise on health-related outcomes according to the baseline frailty status (frail or non-frail) in community-dwelling older adults.

METHODS

Participants included 177 adults aged ≥65 years who carried out multicomponent physical exercises (strength, aerobic, gait and balance) for 40 min, one to three times per week, for 1 year at a day-care center. Bodyweight, comfortable walking speed, 6-min walking distance and Mini-Mental State Examination were measured at baseline and every 3 months. For longitudinal trend, we analyzed the change in scores from baseline for each outcome using the linear mixed effects model. Fixed effects included "group" (frail or non-frail), "time" (4 time points every 3 months, from 3 to 12 months) and "interaction between group and time."

RESULTS

The effect sizes from baseline showed almost all positive values for each outcome. The linear mixed effects model showed significant effects on "interaction between group and time" in changes in bodyweight (P = 0.033), "group" in changes in walking speed (P = 0.013) and "time" in changes in the Mini-Mental State Examination (P < 0.001). Bodyweight showed a decreasing trend in the non-frail group after 3 months, unlike in the frail group. For walking speed, moderate effect sizes (d = 0.67-0.74) were sustained over time in the frail group, as did lesser effect sizes (d = 0.26-0.40) in the non-frail group.

CONCLUSIONS

Exercise-based multicomponent interventions were effective for both groups. The longitudinal effects on walking speed and bodyweight were greater in the frail group. Geriatr Gerontol Int 2022; ••: ••-••.

A Wearable Biofeedback Device to Increase Gait Swing Time Could Have Positive Effects on Gait among Older Adults

Older adults walk with a shorter stride length, reduced hip range of motion (ROM) and higher cadence. These are signs of reductions in walking ability. This study investigated whether using a wireless smart insole system that monitored and provided biofeedback to encourage an extension of swing time could increase stride length and hip flexion, while reducing the cadence. Seven older adults were tested in this study, with and without the biofeedback device, in an outdoor environment. Gait analysis was performed by using GaitRite system and Xsens MVN. Repeated measures analysis demonstrated that with biofeedback, the swing time increased by 6.45%, stride length by 4.52% and hip flexion by 14.73%, with statistical significance. It also decreased the cadence significantly by 5.5%. This study has demonstrated that this smart insole system modified positively the studied gait parameters in older adults and has the potential to improve their walking ability.

Impact of regional white matter hyperintensities on specific gait function in Alzheimer's disease and mild cognitive impairment

BACKGROUND

Gait disturbance and musculoskeletal changes are evident in persons living with Alzheimer's disease (AD). Because complex gait control requires the integration of neural networks, cerebral small vessel disease (SVD), which is highly prevalent in persons with AD, might have an additional impact on gait disturbance. This study investigated whether white matter hyperintensities (WMH) are more predominantly associated with gait disturbance in persons with AD than in individuals with mild cognitive impairment (MCI) and normal cognition (NC) and further identified the regional impact of WMH on specific gait changes.

METHODS

This study included 396 subjects (aged 65 to 86 years, 63.9% female) diagnosed with AD (n = 187), MCI (n = 118), or NC (n = 91). WMH, lacunes, perivascular spaces, and cerebral microbleeds were assessed as markers of SVD. The volume of WMH was quantified in each brain lobe (frontal, temporal, occipital, and parietal) and sublobar regions in the basal ganglia and thalamus. Gait function was assessed using an electronic walkway. We investigated the association between regional WMH and gait disturbance in individuals with AD, MCI, and NC, adjusted for classical and musculoskeletal confounders.

RESULTS

Among markers of SVD, WMH were most associated with gait disturbance. In AD subjects, periventricular WMH in the frontal and parietal lobes were associated with slow gait speed (r_s  = -0.21, P = 0.007 and r_s  = -0.18, P = 0.019, respectively). These lesions were also associated with changes in stride time, double-leg support time, and walking angle (all r_s  > 0.20, P < 0.01). Lesions in the basal ganglia and thalamus were associated with slow gait speed (r_s  = -0.16, P = 0.034 and r_s  = -0.18, P = 0.023, respectively) and greater gait speed variability (r_s  = 0.16, P = 0.034 and r_s  = 0.20, P = 0.010, respectively). MCI subjects showed only associations between sublobar lesions and shorter stride length (r_s  = -0.24, P = 0.016) and increased walking angle (r_s  = 0.32, P = 0.002). NC subjects did not show associations between WMH and gait parameters. MCI and NC subjects were more affected by muscle weakness than WMH for global gait function (r_s  = 0.42, P < 0.001 and r_s  = 0.23, P = 0.046, respectively).

CONCLUSIONS

Persons with AD showed a predominant association between WMH and gait disturbance compared with MCI and NC subjects, and regional WMH had a detrimental effect on specific gait changes.

Calibration-Free Gait Assessment by Foot-Worn Inertial Sensors

Walking is a central activity of daily life, and there is an increasing demand for objective measurement-based gait assessment. In contrast to stationary systems, wearable inertial measurement units (IMUs) have the potential to enable non-restrictive and accurate gait assessment in daily life. We propose a set of algorithms that uses the measurements of two foot-worn IMUs to determine major spatiotemporal gait parameters that are essential for clinical gait assessment: durations of five gait phases for each side as well as stride length, walking speed, and cadence. Compared to many existing methods, the proposed algorithms neither require magnetometers nor a precise mounting of the sensor or dedicated calibration movements. They are therefore suitable for unsupervised use by non-experts in indoor as well as outdoor environments. While previously proposed methods are rarely validated in pathological gait, we evaluate the accuracy of the proposed algorithms on a very broad dataset consisting of 215 trials and three different subject groups walking on a treadmill: healthy subjects (n = 39), walking at three different speeds, as well as orthopedic (n = 62) and neurological (n = 36) patients, walking at a self-selected speed. The results show a very strong correlation of all gait parameters (Pearson's r between 0.83 and 0.99, p < 0.01) between the IMU system and the reference system. The mean absolute difference (MAD) is 1.4 % for the gait phase durations, 1.7 cm for the stride length, 0.04 km/h for the walking speed, and 0.7 steps/min for the cadence. We show that the proposed methods achieve high accuracy not only for a large range of walking speeds but also in pathological gait as it occurs in orthopedic and neurological diseases. In contrast to all previous research, we present calibration-free methods for the estimation of gait phases and spatiotemporal parameters and validate them in a large number of patients with different pathologies. The proposed methods lay the foundation for ubiquitous unsupervised gait assessment in daily-life environments.

Short Physical Performance Battery as a Measure of Physical Performance and Mortality Predictor in Older Adults: A Comprehensive Literature Review

The association between the Short Physical Performance Battery (SPPB) score and several adverse health outcomes, including mortality, has been reported in the scientific literature. We conducted a comprehensive literature review of studies on the relationship between SPPB and mortality. The current paper synthesizes the characteristics and main findings of longitudinal studies available in the literature that investigated the role of the SPPB in predicting mortality in older adults. The studies (n = 40) are from North America, South America, Europe, and Asia; the majority (n = 16) were conducted with community-dwelling older adults and reported an association between lower SPPB scores and a higher risk of mortality, and between higher SPPB scores and higher survival. Nevertheless, few studies have analyzed the accuracy of the instrument to predict mortality. The only study that established cut-off points was conducted with older adults discharged from an acute care hospital. Although an SPPB score lower than 10 seems to predict all-cause mortality, further studies showing cut-off points in specific settings and loco-regional specificities are still necessary.

The Pandora's Box of Frailty Assessments: Which Is the Best for Clinical Purposes in TAVI Patients? A Critical Review

Frailty assessment is recommended before elective transcatheter aortic valve implantation (TAVI) to determine post-interventional prognosis. Several studies have investigated frailty in TAVI-patients using numerous assessments; however, it remains unclear which is the most appropriate tool for clinical practice. Therefore, we evaluate which frailty assessment is mainly used and meaningful for ≤30-day and ≥1-year prognosis in TAVI patients. Randomized controlled or observational studies (prospective/retrospective) investigating all-cause mortality in older (≥70 years) TAVI patients were identified (PubMed; May 2020). In total, 79 studies investigating frailty with 49 different assessments were included. As single markers of frailty, mostly gait speed (23 studies) and serum albumin (16 studies) were used. Higher risk of 1-year mortality was predicted by slower gait speed (highest Hazard Ratios (HR): 14.71; 95% confidence interval (CI) 6.50–33.30) and lower serum albumin level (highest HR: 3.12; 95% CI 1.80–5.42). Composite indices (five items; seven studies) were associated with 30-day (highest Odds Ratio (OR): 15.30; 95% CI 2.71–86.10) and 1-year mortality (highest OR: 2.75; 95% CI 1.55–4.87). In conclusion, single markers of frailty, in particular gait speed, were widely used to predict 1-year mortality. Composite indices were appropriate, as well as a comprehensive assessment of frailty.

Walking cadence (steps/min) and intensity in 61-85-year-old adults: the CADENCE-Adults study

BACKGROUND

Heuristic (i.e., evidence-based, rounded) cadences of ≥100 and ≥ 130 steps/min have consistently corresponded with absolutely-defined moderate (3 metabolic equivalents [METs]) and vigorous (6 METs) physical activity intensity, respectively, in adults 21-60 years of age. There is no consensus regarding similar thresholds in older adults.

PURPOSE

To provide heuristic cadence thresholds for 3, 4, 5, and 6 METs in 61-85-year-old adults.

METHODS

Ninety-eight community-dwelling ambulatory and ostensibly healthy older adults (age = 72.6 ± 6.9 years; 49% women) walked on a treadmill for a series of 5-min bouts (beginning at 0.5 mph with 0.5 mph increments) in this laboratory-based cross-sectional study until: 1) transitioning to running, 2) reaching ≥75% of their age-predicted maximum heart rate, or 3) reporting a Borg rating of perceived exertion > 13. Cadence was directly observed and hand-tallied. Intensity (oxygen uptake [VO2] mL/kg/min) was assessed with indirect calorimetry and converted to METs (1 MET = 3.5 mL/kg/min). Cadence thresholds were identified via segmented mixed effects model regression and using Receiver Operating Characteristic (ROC) curves. Final heuristic cadence thresholds represented an analytical compromise based on classification accuracy (sensitivity, specificity, positive and negative predictive value, and overall accuracy).

RESULTS

Cadences of 103.1 (95% Prediction Interval: 70.0-114.2), 116.4 (105.3-127.4), 129.6 (118.6-140.7), and 142.9 steps/min (131.8-148.4) were identified for 3, 4, 5, and 6 METs, respectively, based on the segmented regression. Comparable values based on ROC analysis were 100.3 (95% Confidence Intervals: 95.7-103.1), 111.5 (106.1-112.9), 116.0 (112.4-120.2), and 128.6 steps/min (128.3-136.4). Heuristic cadence thresholds of 100, 110, and 120 were associated with 3, 4, and 5 METs. Data to inform a threshold for ≥6 METs was limited, as only 6/98 (6.0%) participants achieved this intensity.

CONCLUSIONS

Consistent with previous data collected from 21-40 and 41-60-year-old adults, heuristic cadence thresholds of 100, 110, and 120 steps/min were associated with 3, 4, and 5 METs, respectively, in 61-85-year-old adults. Most older adults tested did not achieve the intensity of ≥6 METs; therefore, our data do not support establishing thresholds corresponding with this intensity level.

TRIAL REGISTRATION

Clinicaltrials.gov NCT02650258 . Registered 24 December 2015.

Estimation of free-living walking cadence from wrist-worn sensor accelerometry data and its association with SF-36 quality of life scores

Objective. We evaluate the stride segmentation performance of the Adaptive Empirical Pattern Transformation (ADEPT) for subsecond-level accelerometry data collected in the free-living environment using a wrist-worn sensor.Approach. We substantially expand the scope of the existing ADEPT pattern-matching algorithm. Methods are applied to subsecond-level accelerometry data collected continuously for 4 weeks in 45 participants, including 30 arthritis and 15 control patients. We estimate the daily walking cadence for each participant and quantify its association with SF-36 quality of life measures.Main results. We provide free, open-source software to segment individual walking strides in subsecond-level accelerometry data. Walking cadence is significantly associated with the role physical score reported via SF-36 after adjusting for age, gender, weight and height.Significance. Methods provide automatic, precise walking stride segmentation, which allows estimation of walking cadence from free-living wrist-worn accelerometry data. Results provide new evidence of associations between free-living walking parameters and health outcomes.

The Smart-Insole Dataset: Gait Analysis Using Wearable Sensors with a Focus on Elderly and Parkinson's Patients

Gait analysis is crucial for the detection and management of various neurological and musculoskeletal disorders. The identification of gait events is valuable for enhancing gait analysis, developing accurate monitoring systems, and evaluating treatments for pathological gait. The aim of this work is to introduce the Smart-Insole Dataset to be used for the development and evaluation of computational methods focusing on gait analysis. Towards this objective, temporal and spatial characteristics of gait have been estimated as the first insight of pathology. The Smart-Insole dataset includes data derived from pressure sensor insoles, while 29 participants (healthy adults, elderly, Parkinson’s disease patients) performed two different sets of tests: The Walk Straight and Turn test, and a modified version of the Timed Up and Go test. A neurologist specialized in movement disorders evaluated the performance of the participants by rating four items of the MDS-Unified Parkinson’s Disease Rating Scale. The annotation of the dataset was performed by a team of experienced computer scientists, manually and using a gait event detection algorithm. The results evidence the discrimination between the different groups, and the verification of established assumptions regarding gait characteristics of the elderly and patients suffering from Parkinson’s disease.

12-Week Exercise Training of Knee Joint and Squat Movement Improves Gait Ability in Older Women

This study analyzed the effects of an exercise training program consisting of a knee joint complex exercise device (leg-link system) with digitally controlled active motion function and squat movement on physical fitness and gait ability of elderly women aged 70 or above. Fifty four (54) elderly women aged 70 or above were divided into three groups as control group (n = 18), aerobic training group (n = 18), and combined training group with resistance and aerobic exercise (n = 18). Health-related physical fitness, gait ability-related physical fitness, and the temporal and spatial parameters of gait ability were compared. The health-related physical fitness after the 12-week training was not significantly altered in control group, whereas combined training group showed significant increase in all factors (p < 0.05) and aerobic training group showed significant increase (p < 0.05) only in the physical efficiency index. The gait ability-related physical fitness and all items of the temporal and spatial parameters of gait were found to have significantly increased (p < 0.05) in combined training group after the 12-week exercise training; however, in aerobic training group, only the factors related to muscular endurance and balance showed significant increase (p < 0.05). This study suggested that the exercise training consisting of knee joint complex exercise with digitally controlled active motion function and squat exercise for strengthening lower extremities and core muscles had positive effects on enhancing the ambulatory competence in elderly women.

Evaluation of impact-shock on gait after the implementation of two different training programs in older adults

BACKGROUND

Gait is negatively affected with increasing age. It is widely accepted that training produces physical-functional improvements in older adults, which can be assessed with numerous physical-functional tests. However, very few studies have been carried out using accelerometry to analyse the training effect on kinetic and kinematic variables in older adults, and there is no one that investigate the effects of two different training programs. Therefore, the aim of this study is to analyse the effects of an interval-walking program and a multicomponent program on the acceleration impacts, shock attenuation, step-length, stride frequency, and gait speed in older adults.

METHODS

23 participants were divided into multicomponent training group [n = 12, 7 female, 71.58 (4.56) years] and interval-walking group [n = 11, 6 female, 69.64 (3.56) years]. We evaluated the participants using three triaxial accelerometers, placing one on the distal end of each tibia and one on the forehead.

FINDINGS

After 14 weeks' of training, the maximum acceleration values both for the head accelerometer and for the non-dominant tibia, as well as the attenuation in the same leg, increased in the multicomponent training group. The maximum acceleration values for the head and the stride frequency also increased in the interval-walking group. Lower limb strength improved in both groups.

INTERPRETATION

Given the benefits we found for each of these programs, we encourage their consideration when planning older adults training programs and suggest that multicomponent programs should be introduced prior to the start of walking-based programs.

Interactions Between Different Age-Related Factors Affecting Balance Control in Walking

Maintaining balance during walking is a continuous sensorimotor control problem. Throughout the movement, the central nervous system has to collect sensory data about the current state of the body in space, use this information to detect possible threats to balance and adapt the movement pattern to ensure stability. Failure of this sensorimotor loop can lead to dire consequences in the form of falls, injury and death. Such failures tend to become more prevalent as people get older. While research has established a number of factors associated with higher risk of falls, we know relatively little about age-related changes of the underlying sensorimotor control loop and how such changes are related to empirically established risk factors. This paper approaches the problem of age-related fall risk from a neural control perspective. We begin by summarizing recent empirical findings about the neural control laws mapping sensory input to motor output for balance control during walking. These findings were established in young, neurotypical study populations and establish a baseline of sensorimotor control of balance. We then review correlates for deteriorating balance control in older adults, of muscle weakness, slow walking, cognitive decline, and increased visual dependency. While empirical associations between these factors and fall risk have been established reasonably well, we know relatively little about the underlying causal relationships. Establishing such causal relationships is hard, because the different factors all co-vary with age and are difficult to isolate empirically. One option to analyze the role of an individual factor for balance control is to use computational models of walking comprising all levels of the sensorimotor control loop. We introduce one such model that generates walking movement patterns from a short list of spinal reflex modules with limited supraspinal modulation for balance. We show how this model can be used to simulate empirical studies, and how comparison between the model and empirical results can indicate gaps in our current understanding of balance control. We also show how different aspects of aging can be added to this model to study their effect on balance control in isolation.

Age-stratified differences of physical capacity in rural community-dwelling Taiwanese older women: A cross-sectional study

OBJECTIVES

Physical capacity decline may precede physical disability. We explored age-related physical capacity decline among rural community-dwelling Taiwanese older women to provide reference values and to identify indicators of early-onset decline in physical capacity.

METHODS

Older women aged 65-96 were recruited from rural community centers. Physical capacity was measured by handgrip strength (HS), gait speed (GS), five-times-sit-to-stand (5xSTS), timed up and go (TUG), and the Berg balance scale (BBS). Participants were stratified into four age groups: 65-69, 70-74, 75-79, and ≥80 years.

RESULTS

Of 137 participants, 61 % exhibited poor 5xSTS, 34-49 % showed low HS, poor TUG and BBS, and 26 % had slow GS. The mean values in GS, HS, 5xSTS, TUG, and BBS were 1.02 m/s, 17.8 kg, 14.5 s, 12.6 s, and 50 points, respectively. Abnormal mean values were first noted at age 70-74 years for 5xSTS, age 75-79 years for HS, TUG, and BBS, and age ≥80 years for GS. Also, more than half the participants exhibited the first poor 5xSTS at age 70-74 years; the first poor HS and TUG at age 75-79 years; and lastly, the first poor BBS and GS at age ≥80 years. At age 65-69 years, 14-41 % of participants reported poor performance in all measures except for GS.

CONCLUSIONS

Low HS and poor 5xSTS and TUG performance were more common and had earlier onset than slow GS. More attention should be directed toward the 5xSTS, TUG, and HS in rural community-dwelling Taiwanese older women.

Factors Related to Self-rated Health in Older Adults: A Clinical Approach Using the International Classification of Functioning, Disability, and Health (ICF) Model

BACKGROUND AND PURPOSE

A growing population of older adults will require health care professionals to become increasingly knowledgeable in geriatric care. Patient ratings, functional measures, and emphasis on health and wellness should be part of geriatric physical therapy practice. The purpose of the current study was to examine relationships between self-rated health (SRH) and movement-related variables in older adults using the International Classification of Functioning, Disability, and Health (ICF) as a research framework. Associations between body mass index (BMI), gait, and balance confidence were also explored.

METHODS

Thirty older adults (mean age = 74.1 years; 18 women and 12 men) participated in the study and completed the following questionnaires: SRH, Short Activities-specific Balance Confidence scale, Keele Assessment of Participation, and the Neighborhood Environment Walkability Scale-Abbreviated. Spatiotemporal gait parameters, BMI, and isokinetic knee extensor strength were also assessed.

RESULTS

Bivariate results indicated significant associations between SRH and double-support time during gait (rs = -0.6, P < .001), gait speed (rs = 0.4, P = .05), step length (rs = 0.4, P = .05), BMI (rs = -0.4, P = .015), and hilliness of neighborhood (rs = -0.4, P = .015). Individual regression models, controlling for education and age, demonstrated that double-support time was the strongest predictor of SRH (R = 0.50, P = .001). Comparisons of the low versus high BMI groups indicated more favorable balance confidence and gait characteristics for the low BMI group, particularly in double support (t = -3.8, P = .001).

CONCLUSIONS

SRH should be considered as a quick, patient-focused assessment of health in older adults. Measures of double-support time and BMI may provide clinicians with useful information about their geriatric patients' overall health and function.

Optic flow improves step width and length in older adults while performing dual task

BACKGROUND

Dual-task paradigms are used to investigate gait and cognitive declines in older adults (OA). Optic-flow is a virtual reality environment where the scene flows past the subject while walking on a treadmill, mimicking real-life locomotion.

AIMS

To investigate cost of environment (no optic-flow v. optic-flow) while completing single- and dual-task walking and dual-task costs (DTC; single- v. dual-task) in optic-flow and no optic-flow environments.

METHODS

Twenty OA and seven younger adults (YA) walked on a self-paced treadmill in 3-min segments per task and both environments. Five task conditions included: no task, semantic fluency (category), phonemic fluency (letters), word reading, and serial-subtraction.

RESULTS

OAs had a benefit of optic-flow compared to no optic-flow for step width (p = 0.015) and step length (p = 0.045) during letters compared to the YA. During letters, OA experienced improvement in step width DTC; whereas YA had a decrement in step width DTC from no optic-flow to optic-flow (p = 0.038). During serial-subtraction, OA had less step width DTC when compared to YA in both environments (p = 0.02).

DISCUSSION

During letters, step width and step length improved in OA while walking in optic-flow. Also, step width DTC differed between the two groups. Sensory information from optic-flow appears to benefit OA. Letters relies more on verbal ability and word knowledge, which are preserved in aging. However, YA use a complex speech style during dual tasking, searching for complex words and an increased speed of speech.

CONCLUSIONS

OA can benefit from optic-flow by improving spatial gait parameters, specifically, step width, during dual-task walking.

Reference values of gait parameters measured with a plantar pressure platform in community-dwelling older Japanese adults

Background

Gait measures such as gait speed, stride length, step width, and stance duration change with advanced age and are associated with adverse health outcomes among older adults. The stride-to-stride variabilities of gait measures are also related to falls and cognitive decline in older adults; however, reference values of these gait parameters in older Japanese adults do not exist. This study aimed to determine the reference values of gait parameters as measured by a plantar pressure platform in community-dwelling older Japanese adults.

Methods

Community-dwelling adults (N=1,212) who were independent in basic activities of daily living and aged 70-96 years (491 men, 721 women) completed the gait performance measurement in a geriatric health assessment. We assessed 10 gait performance measures with a plantar pressure platform system (P-WALK, BTS Bioengineering) and calculated means and coefficient of variations (CVs) of the gait measures as well as quintiles for those gait parameters per age group among men and women.

Results

Mean (SDs) of gait speed, stride length, step width, and stance durations were 1.26 (0.24) meters per second (m/s), 121.9 (19.8) cm, 24.0 (3.2) cm, and 552.4 (60.4) milliseconds (ms), respectively, in men, and 1.27 (0.21) m/s, 115.7 (16.3) cm, 17.9 (2.8) cm, and 517.6 (59.8) ms, respectively, in women. Mean of CVs (SD) of stride length, step width, and single-stance duration were 2.76 (1.35), 12.06 (3.98), and 5.74 (2.66), respectively, in men and 2.69 (1.24), 15.65 (4.53), and 5.77 (2.40), respectively, in women. Gait parameters (except CVs of step width) declined significantly with age regardless of gender (P< 0.01 for trends).

Conclusion

This study determined age group dependent gait parameter reference values, presented as means with quintile ranges, in community-dwelling older Japanese adults. These reference values may be useful metrics for gait assessment in the elderly.

Capacidad de marcha y dependencia funcional en adultos mayores con alteración visual

Introducción: La alteración visual puede producir cambios en la marcha y afectar la autonomía del adulto mayor, entendida como la necesidad de ayuda de otras personas o aditamentos para realizar, adecuadamente, sus actividades de la vida diaria. Objetivo: Conocer la relación entre la capacidad de marcha y dependencia funcional en adultos mayores con alteración de la agudeza visual. Material y métodos: Estudio descriptivo y correlacional, en una población de adultos mayores con alteración de la agudeza visual, muestra conformada por 94 adultos mayores. La marcha se midió con el sistema GAITRite, para la dependencia en Actividades Básicas de la Vida Diaria, se utilizó el Índice de Barthel, para las Actividades Instrumentales de la Vida Diaria el índice de Lawton y Brody. Resultados: La capacidad de marcha y dependencia funcional, presentó relación positiva entre la velocidad de marcha (p = 0.000) y longitud del paso (p = 0.000) con las ABVD; la velocidad de marcha (p = 0.000), cadencia (p = 0.023) y longitud del paso (p = 0.000) con las AIVD y relación negativa entre la amplitud del paso (p = 0.012) y AIVD. Conclusión: La valoración de la marcha en los AM con alteración en la agudeza visual, desde el primer nivel de atención, permitirá desarrollar intervenciones y programas encaminados a preservar la independencia del adulto mayor, reducir las tasas de morbilidad, disminuir costos en salud y contribuir en una mejor calidad de vida.

Physical frailty and gait speed in community elderly: a systematic review

OBJECTIVE

To identify the outcomes of studies on gait speed and its use as a marker of physical frailty in community elderly.

METHOD

Systematic review of the literature performed in the following databases: LILACS, SciELO, MEDLINE/PubMed, ScienceDirect, Scopus and ProQuest. The studies were evaluated by STROBE statement, and the PRISMA recommendations were adopted.

RESULTS

There were 6,303 studies, and 49 of them met the inclusion criteria. Of the total number of studies, 91.8% described the way of measuring gait speed. Of these, 28.6% used the distance of 4.6 meters, and 34.7% adopted values below 20% as cutoff points for reduced gait speed, procedures in accordance with the frailty phenotype. Regarding the outcomes, in 30.6% of studies, there was an association between gait speed and variables of disability, frailty, sedentary lifestyle, falls, muscular weakness, diseases, body fat, cognitive impairment, mortality, stress, lower life satisfaction, lower quality of life, napping duration, and poor performance in quantitative parameters of gait in community elderly.

CONCLUSION

The results reinforce the association between gait speed, physical frailty and health indicator variables in community elderly.

An examination of the heterogeneity in the pattern and association between rates of change in grip strength and global cognition in late life. A multivariate growth mixture modelling approach

Background

previous research has demonstrated how older adults exhibit different patterns of change in cognitive and physical functioning, suggesting differences in the underlying causal processes.

Objective

to (i) identify subgroups of older adults that best account for different patterns of longitudinal change in performance on global cognition and grip strength, (ii) examine the interrelationship between global cognition and grip strength trajectories within these subgroups and (iii) identify demographic and health-related markers of class membership.

Methods

multivariate growth mixture models (GMM) were used to identify groups of individuals with similar developmental trajectories of muscle strength measured by grip strength, and global cognition measured by Mini Mental State Examination (MMSE).

Results

GMM analyses indicated high, moderate and low functioning groups. Individuals in the high and moderate classes demonstrated better cognitive and physical functioning at the start of the study and less decline than those in the low functioning group. Notably, cognitive performance was related to physical functioning at study entry only among individuals in the low functioning group.

Conclusion

the study demonstrates the applicability of the multivariate GMM to achieve a better understanding of the heterogeneity of various aging related processes.

Mental Well-Being of Older People in Finland during the First Year in Senior Housing and Its Association with Physical Performance

Growing numbers of older people relocate to senior housing, when their physical or mental performance declines. The relocation is known to be one of the most stressful events in the life of older people and affect their mental and physical well-being. More information about the relationships between mental and physical parameters is required. We examined self-reported mental well-being of 81 older people (aged 59⁻93, living in northern Finland), and changes in it 3 and 12 months after relocation to senior housing. The first measurement was 3 months and the second measurement 12 months after relocation. Most participants were female (70%). Their physical performance was also measured, and associations between these two were analyzed. After 12 months, mental capability was very good or quite good in 38% of participants, however 22% of participants felt depressive symptoms daily or weekly. Moreover, 39% of participants reported daily or weekly loneliness. After 12 months participants reported a significant increase in forgetting appointments, losing items and difficulties in learn new things. They felt that opportunities to make decisions concerning their own life significantly decreased. Furthermore, their instrumental activities of daily living (IADL), dominant hand’s grip strength and walking speed decreased significantly. Opportunities to make decisions concerning their life, feeling safe, loneliness, sleeping problems, negative thoughts as well as fear of falling or having an accident outdoors were associated with these physical parameters. In addition to assessing physical performance and regular exercise, the various components of mental well-being and their interactions with physical performance should be considered during adjustment to senior housing.

Impact of Physical Activities on Frailty in Community-Dwelling Older Women

Aims

The aim of the study was to determine whether increased physical activities (PA) affect frailty for old women, 75 years and older (OO), compared to 60-74 years old (YO).

Methods

This crosssectional study measured 19 frailty indicators (muscle strength and endurance, balance, gait characteristics, and function), using 46 community-dwelling women. PA were divided into three levels by caloric expenditure per week (<2,000 kcal/week, 2,000-3,999 kcal/week,>4,000 kcal/week).

Results

As PA level increased, a gap (=difference) between OO and YO narrowed for step length and function, but for quadriceps strength and endurance, a gap widened.

Conclusions

Frailty progresses with aging but older women who engage in a high level of physical activity (>4,000 kcal/week) can increase mobility and functional capacity, but not for muscle strength and endurance. Starting regular resistance training activities early in the aging process is critical to improve or maintain muscle quality to offset age-related frailty.

Social Environment of Older People during the First Year in Senior Housing and Its Association with Physical Performance

Increasing numbers of older people relocate into senior housing when their physical performance declines. The change in social environment is known to affect their wellbeing, providing both challenges and opportunities, but more information on the relations between social and physical parameters is required. Thus, we elicited perceptions of the social environment of 81 older people (aged 59-93 years, living in northern Finland) and changes in it 3 and 12 months after relocation to senior housing. We also measured their physical performance, then analysed associations between the social and physical variables. Participants reported that they had freedom to do whatever they liked and generally had enough contact with close people (which have recognized importance for older people's wellbeing), but changes in their physical condition limited their social activity. Moreover, their usual walking speed, dominant hand's grip strength and instrumental activities of daily living (IADL) significantly decreased. The pleasantness of the residential community, peer support, constraints on social activity imposed by changes in physical condition, meaningful activity at home and meeting close people all affected these physical performance parameters. Clearly, in addition to assessing physical performance and encouraging regular exercise, the complex interactions among social factors, physical performance and wellbeing should be considered when addressing individuals' needs.

Mastoid vibration affects dynamic postural control during gait in healthy older adults

Vestibular disorders are difficult to diagnose early due to the lack of a systematic assessment. Our previous work has developed a reliable experimental design and the result shows promising results that vestibular sensory input while walking could be affected through mastoid vibration (MV) and changes are in the direction of motion. In the present paper, we wanted to extend this work to older adults and investigate how manipulating sensory input through mastoid vibration (MV) could affect dynamic postural control during walking. Three levels of MV (none, unilateral, and bilateral) applied via vibrating elements placed on the mastoid processes were combined with the Locomotor Sensory Organization Test (LSOT) paradigm to challenge the visual and somatosensory systems. We hypothesized that the MV would affect sway variability during walking in older adults. Our results revealed that MV significantly not only increased the amount of sway variability but also decreased the temporal structure of sway variability only in anterior-posterior direction. Importantly, the bilateral MV stimulation generally produced larger effects than the unilateral. This is an important finding that confirmed our experimental design and the results produced could guide a more reliable screening of vestibular system deterioration.

The association of waist circumference with walking difficulty among adults with or at risk of knee osteoarthritis: the Osteoarthritis Initiative

OBJECTIVE

Excess weight is a known risk factor for functional limitation and common in adults with knee osteoarthritis (OA). We asked to what extent high waist circumference was linked with developing difficulty with walking speed and distance over 4 years in adults with or at risk of knee OA.

METHOD

Using data from the Osteoarthritis Initiative (OAI), we employed World Health Organization (WHO) categories for Body Mass Index (BMI) and waist circumference (small/medium and large). Difficulty with speed was defined by slow gait: <1.2 m/s during a 20-m walk, and difficulty with distance was defined by an inability to walk 400 m. We calculated risk ratios (RR) to examine the likelihood of developing difficulty with distance and speed using obesity and waist circumference as predictors with RRs adjusted for potential confounders (i.e., age, sex, race, education, physical activity, and OA status).

RESULTS

Participants with obesity and large waists were 2.2 times more likely to have difficulty with speed at 4 years compared to healthy weight and small/medium waisted participants (Adjusted RR 2.2 [95% Confidence interval (CI) 1.6, 3.1], P < .0001). Participants with obesity and a large waist circumference had 2.4 times the risk of developing the inability to walk 400 m compared with those with a healthy BMI and small/medium waist circumference (Adjusted RR 0.9 [95% CI 1.6, 3.7], P < .0001).

CONCLUSIONS

Waist circumference may be a main risk factor for developing difficulty with speed in adults with or at risk of knee OA.

Older adult Alexander Technique practitioners walk differently than healthy age-matched controls

The Alexander Technique (AT) seeks to eliminate harmful patterns of tension that interfere with the control of posture and movement and in doing so, it may serve as a viable intervention method for increasing gait efficacy in older adults. The purpose of this study was to compare the comfortable pace gait kinematics of older AT practitioners with those of healthy, age-matched controls. Participants were six licensed AT practitioners and seven healthy age-matched controls between the ages of 61-76. During the stance phase, AT participants exhibited significantly greater ankle stance range of motion (ROM) and plantar flexion at toe off, as well as lower ROM of the trunk and head compared to controls. During the swing phase, the AT practitioners had significantly increased hip and knee flexion and a trend toward significantly increased dorsiflexion. The findings suggest that the older AT practitioners walked with gait patterns more similar to those found in the literature for younger adults. These promising results highlight the need for further research to assess the AT's potential role as an intervention method for ameliorating the deleterious changes in gait that occur with aging.

Dual Tasking for the Differentiation between Depression and Mild Cognitive Impairment

Differentiation of mild cognitive impairment from depression in elderly adults is a clinically relevant issue which is not sufficiently solved. Gait and dual task (DT) parameters may have the potential to complement current diagnostic work-up, as both dementia and depression are associated with changes of gait and DT parameters.

METHODS

Seven hundred and four participants of the TREND study (Tübinger evaluation of Risk factors for Early detection of NeuroDegeneration) aged 50-80 years were assessed using the Consortium to Establish a Registry for Alzheimer's Disease Plus test battery for testing cognition and Beck's Depression Inventory for evaluation of depression. Based on these results, four groups were defined: acute depressed (N = 53), cognitively mildly impaired (N = 97), acute depressed, and cognitively mildly impaired (N = 15), and controls (N = 536). Participants underwent a 20 m walk and checking boxes task under single (ST) and DT conditions. ST and DT performance and dual task costs (DTC) were calculated. Due to the typical age of increasing incidence of depressive and also cognitive symptoms, the 7th decade was calculated separately.

RESULTS

ST speeds of gait and checking boxes, DT walking speed, and walking DTC were significantly different between groups. Healthy controls were the fastest in all paradigms and cognitively mildly impaired had higher DTC than depressed individuals. Additionally, we constructed a multivariate predictive model differentiating the groups on a single-subject level.

CONCLUSION

DT parameters are simply and comfortably measureable, and DTC can easily be determined. The combination of these parameters allows a differentiation of depressed and cognitively mildly impaired elderly adults.

Validity of the iPhone M7 motion co-processor as a pedometer for able-bodied ambulation

Physical activity benefits for disease prevention are well-established. Smartphones offer a convenient platform for community-based step count estimation to monitor and encourage physical activity. Accuracy is dependent on hardware-software platforms, creating a recurring challenge for validation, but the Apple iPhone® M7 motion co-processor provides a standardised method that helps address this issue. Validity of the M7 to record step count for level-ground, able-bodied walking at three self-selected speeds, and agreement with the StepWatch^TM was assessed. Steps were measured concurrently with the iPhone® (custom application to extract step count), StepWatch^TM and manual count. Agreement between iPhone® and manual/StepWatch^TM count was estimated through Pearson correlation and Bland-Altman analyses. Data from 20 participants suggested that iPhone® step count correlations with manual and StepWatch^TM were strong for customary (1.3 ± 0.1 m/s) and fast (1.8 ± 0.2 m/s) speeds, but weak for the slow (1.0 ± 0.1 m/s) speed. Mean absolute error (manual-iPhone®) was 21%, 8% and 4% for the slow, customary and fast speeds, respectively. The M7 accurately records step count during customary and fast walking speeds, but is prone to considerable inaccuracies at slow speeds which has important implications for certain patient groups. The iPhone® may be a suitable alternative to the StepWatch^TM for only faster walking speeds.

Role of physical activity, physical fitness, and chronic health conditions on the physical independence of community-dwelling older adults over a 5-year period

The variability in the individual characteristics and habits could help determine how older adults maintain independence. The impact of the variability in physical activity, physical fitness, body composition, and chronic health conditions (co-morbidities) on the independence of older adults, especially over time, is seldom examined. This study aims to analyze quantitatively the impact of baseline values and changes in physical activity, physical fitness, body composition, and co-morbidities on the physical independence of community-dwelling, older adults over a 5-year period. Data from 106 and 85 community-dwelling adults (≥60 years) were collected at baseline and after five years, respectively. Linear regression selected the main predictors of changes in physical independence as follows: the baseline physical independence (β=0.032, R(2)=9.9%) and co-morbidities (β=-0.191, R(2)=6.3%) and the changes in co-morbidities (β=-0.244, R(2)=10.8%), agility (β=-0.288, R(2)=6.7%), aerobic endurance (β=0.007, R(2)=3.2%), and walking expenditure (β=0.001, R(2)=5.1%) (p<0.05). In conclusion, baseline physical independence, baseline co-morbidities, and changes in co-morbidities, walking, agility, and aerobic endurance predicted physical independence over five years regardless of age and gender. Gains of up to 8.3% in physical independence were associated with improvements in these variables, which corresponds to regaining independence for performing one or two activities of daily living.

Relation of Step Length to Magnetic Resonance Imaging-Detected Structural Damage in the Patellofemoral Joint: The Multicenter Osteoarthritis Study

OBJECTIVE

To investigate the relationship of step length to the sex-specific prevalence and worsening of magnetic resonance imaging (MRI)-detected structural damage in the patellofemoral (PF) joint among a cohort of older women and men with or at risk of knee osteoarthritis (OA).

METHODS

The Multicenter Osteoarthritis Study is a cohort study of persons ages 50-79 years with or at risk of knee OA. Step length was assessed using the GAITRite walkway (CIR Systems) at the 60-month visit, and cartilage damage and bone marrow lesions (BMLs) were graded on MRI at the 60- and 84-month visits. Step length was divided into sex-specific quintiles, and the relationship of step length to the prevalence and worsening of cartilage damage and BMLs in the PF joint was examined using logistic regression, adjusting for age, body mass index (BMI), leg length, and tibiofemoral joint structural damage.

RESULTS

In 1,053 knees, 4,094 and 4,083 PF joint subregions were studied for the cartilage and BML analyses, respectively. Mean ± SD age was 65.6 ± 8.1 years and mean ± SD BMI was 29.1 ± 4.7 kg/m(2) ; 62% of participants were female. In women, compared to those with the shortest step length, those with the longest step length had 0.62 (95% confidence interval [95% CI] 0.43-0.88) and 0.59 (95% CI 0.40-0.87) times the odds of cartilage damage and BMLs, respectively. There was no cross-sectional association in men, and no longitudinal association in either sex.

CONCLUSION

Women with PF joint structural damage may adapt their gait by shortening their step length, but this may not be sufficient to reduce the risk of worsening damage over time.