Effects of muscle fatigue on gait characteristics under single and dual-task conditions in young and older adults

Muscle fatigue and dual-task walking (e.g., concurrent performance of a cognitive interference (CI) while walking) represent major fall risk factors in young and older adults. Thus, the objectives of this study were to examine the effects of muscle fatigue on gait characteristics under single and dual-task conditions in young and older adults and to determine the impact of muscle fatigue on dual-task costs while walking

Association between dual task-related decrease in walking speed and real versus imagined Timed Up and Go test performance

Background and aims: To examine whether older people with markedly dual task-related decreases in walking speed—a marker of disturbed higher-level gait control and falls—have a larger discrepancy between real and imagined Timed Up and Go (TUG) test times than those with less dual task-related decreases in walking speed. Methods: Based on a prospective cross-sectional study, 193 older adults (mean age 77.4±5.9years; 44.0% women) referred to and consecutively assessed at a Swiss university clinic for a gait analysis to assess either gait disorders, fall risk or memory disorders were included. For all participants, walking speed was measured using a GAITRite® electronic walkway system during usual walking at self-selected pace and while dual tasking (i.e., usual walking and simultaneously counting backwards out loud). In addition, real Timed Up and Go (TUGr) and imagined Timed Up and Go (TUGi) (i.e., the time needed to imagine performing the TUGr) times were measured with a stopwatch. Differences between both walking conditionsfor walking speed (delta of walking speed) and both TUG conditions (delta of TUG time) were calculated. Age, gender, height, total number drugs taken per day, daily use of psychoactive drugs, use of walking aid, history of falls, Mini-Mental State Examination score, near vision and education level were used as covariables in this analysis. Results: Participants were categorized into two groups based on being in the lowest tertian (i.e., <33%: group A corresponding to participants undisturbed by dual task) or not (i.e., ≥33%: group B corresponding to participants disturbed by dual task) of the delta of walking speed. In both groups, TUGr and TUGi times were similar (P=.169 and P=.839). In both groups, TUGi was faster than TUGr (P<.001). Delta of TUG time was significantly greater in group B compared to group A (P<.001). After adjustment for all covariables, only the delta of walking speed was significantly associated with the delta of TUG time (P=<.001). Stepwise backward regression showed that polypharmacy (P=.017) and delta of walking speed (P=<.001) were associated with an increase in delta of TUG time, whereas an increased MMSE score (P=.030) was associated with a decrease in delta of TUG time. Conclusion: These findings show that a large discrepancy between real and imagined TUG performances is significantly correlated with a decrease in walking speed while dual tasking, and thus may also be a surrogate marker of disturbed higher-level gait control. The quickly and easily performed TUG tests may represent a feasible, practical screening tool for early detection of higher-level gait disorders in older adult

Age-related effects on postural control under multi-task conditions

Changes in postural sway and gait patterns due to simultaneously performed cognitive (CI) and/or motor interference (MI) tasks have previously been reported and are associated with an increased risk of falling in older adults

The effect of three different types of walking aids on spatio-temporal gait parameters in community-dwelling older adults

Background and aims: Gait and balance impairments lead to falls and injuries in older people. Walking aids are meant to increase gait safety and prevent falls, yet little is known about how their use alters gait parameters. This study aimed to quantify gait in older adults during walking without and with different walking aids and to compare gait parameters to matched controls. Methods: This retrospective study included 65 older (≥60years) community dwellers who used a cane, crutch or walker and 195 independently mobile-matched controls. Spatio-temporal gait parameters were measured with an electronic walkway system during normal walking. Results: When walking unaided or aided, walking aid users had significantly worse gait than matched controls. Significant differences between the walking aid groups were found for stride time variability (cane vs. walker) in walking unaided only. Gait performances significantly improved when assessed with vs. without the walking aid for the cane (increased stride time and length, decreased cadence and stride length variability), crutch (increased stride time and length, decreased cadence, stride length variability and double support) and walker (increased gait speed and stride length, decreased base of support and double support) users. Conclusion: Gait in older adults who use a walking aid is more irregular and unstable than gait in independently mobile older adults. Walking aid users have better gait when using their walking aid than when walking without it. The changes in gait were different for the different types of walking aids used. These study results may help better understand gait in older adults and differentiate between pathological gait changes and compensatory gait changes due to the use of a walking aid

Effects of a salsa dance training on balance and strength performance in older adults

Deficits in static and particularly dynamic postural control and force production have frequently been associated with an increased risk of falling in older adults.; The objectives of this study were to investigate the effects of salsa dancing on measures of static/dynamic postural control and leg extensor power in seniors.; Twenty-eight healthy older adults were randomly assigned to an intervention group (INT, n = 14, age 71.6 ± 5.3 years) to conduct an 8-week progressive salsa dancing programme or a control group (CON, n = 14, age 68.9 ± 4.7 years). Static postural control was measured during one-legged stance on a balance platform and dynamic postural control was obtained while walking on an instrumented walkway. Leg extensor power was assessed during a countermovement jump on a force plate.; Programme compliance was excellent with participants of the INT group completing 92.5% of the dancing sessions. A tendency towards an improvement in the selected measures of static postural control was observed in the INT group as compared to the CON group. Significant group × test interactions were found for stride velocity, length and time. Post hoc analyses revealed significant increases in stride velocity and length, and concomitant decreases in stride time. However, salsa dancing did not have significant effects on various measures of gait variability and leg extensor power.; Salsa proved to be a safe and feasible exercise programme for older adults accompanied with a high adherence rate. Age-related deficits in measures of static and particularly dynamic postural control can be mitigated by salsa dancing in older adults. High physical activity and fitness/mobility levels of our participants could be responsible for the nonsignificant findings in gait variability and leg extensor power

Motoric Cognitive Risk Syndrome: Multicountry Prevalence and Dementia Risk

OBJECTIVES: Our objective is to report prevalence of motoric cognitive risk syndrome (MCR), a newly described predementia syndrome characterized by slow gait and cognitive complaints, in multiple countries, and its association with dementia risk. METHODS: Pooled MCR prevalence analysis of individual data from 26,802 adults without dementia and disability aged 60 years and older from 22 cohorts from 17 countries. We also examined risk of incident cognitive impairment (Mini-Mental State Examination decline ≥4 points) and dementia associated with MCR in 4,812 individuals without dementia with baseline Mini-Mental State Examination scores ≥25 from 4 prospective cohort studies using Cox models adjusted for potential confounders. RESULTS: At baseline, 2,808 of the 26,802 participants met MCR criteria. Pooled MCR prevalence was 9.7% (95% confidence interval [CI] 8.2%-11.2%). MCR prevalence was higher with older age but there were no sex differences. MCR predicted risk of developing incident cognitive impairment in the pooled sample (adjusted hazard ratio [aHR] 2.0, 95% CI 1.7-2.4); aHRs were 1.5 to 2.7 in the individual cohorts. MCR also predicted dementia in the pooled sample (aHR 1.9, 95% CI 1.5-2.3). The results persisted even after excluding participants with possible cognitive impairment, accounting for early dementia, and diagnostic overlap with other predementia syndromes. CONCLUSION: MCR is common in older adults, and is a strong and early risk factor for cognitive decline. This clinical approach can be easily applied to identify high-risk seniors in a wide variety of settings

Prevalence and incidence of iron deficiency in European community-dwelling older adults : An observational analysis of the DO-HEALTH trial

Background and aim Iron deficiency is associated with increased morbidity and mortality in older adults. However, data on its prevalence and incidence among older adults is limited. The aim of this study was to investigate the prevalence and incidence of iron deficiency in European community-dwelling older adults aged ≥ 70 years. Methods Secondary analysis of the DO-HEALTH trial, a 3-year clinical trial including 2157 community-dwelling adults aged ≥ 70 years from Austria, France, Germany, Portugal and Switzerland. Iron deficiency was defined as soluble transferrin receptor (sTfR) > 28.1 nmol/L. Prevalence and incidence rate (IR) of iron deficiency per 100 person-years were examined overall and stratified by sex, age group, and country. Sensitivity analysis for three commonly used definitions of iron deficiency (ferritin  1.5) were also performed. Results Out of 2157 participants, 2141 had sTfR measured at baseline (mean age 74.9 years; 61.5% women). The prevalence of iron deficiency at baseline was 26.8%, and did not differ by sex, but by age (35.6% in age group ≥ 80, 29.3% in age group 75–79, 23.2% in age group 70–74); P  1.5. Occurrences of iron deficiency were observed with IR per 100 person-years of 9.2 (95% CI 8.3–10.1) and did not significantly differ by sex or age group. The highest IR per 100 person-years was observed in Austria (20.8, 95% CI 16.1–26.9), the lowest in Germany (6.1, 95% CI 4.7–8.0). Regarding the other definitions of iron deficiency, the IR per 100 person-years was 4.5 (95% CI 4.0–4.9) for ferritin  1.5. Conclusions Iron deficiency is frequent among relatively healthy European older adults, with people aged ≥ 80 years and residence in Austria and Portugal associated with the highest risk

Motor cognitive dual tasking: Early detection of gait impairment, fall risk and cognitive decline

Background: Gait and cognition are closely associated. Older adults with gait deficits have an increased risk of developing cognitive deficits and cognitive deficits are associated with worsened gait. Both gait and cognitive impairments are risk factors for falls in older adults. Objectives: The aims of this article are (1) to highlight the association between gait and cognition, particularly executive function, (2) to present motor cognitive dual tasking test paradigms and (3) to provide an algorithm for standardized mobility tests that can quickly and easily be performed in a private practice or on a hospital ward. Materials and methods: A Pubmed review of current literature on the topic as well as the personal experience and recommendations of the authors are presented. Assessments summarized: clock drawing test, stops walking when talking test, normal walking speed, timed up and go test, regular, as a dual task and imagined. Results: It is recommended that at least two of the presented assessments should be performed at each clinical visit in all patients age 65 years or older. If one of the assessments presented provides abnormal results, patients should be referred to a gait specialist for an in-depth quantitative gait analysis. Conclusion: Assessments of functional mobility, fall risk and cognition should be an integral part of every comprehensive geriatric assessment. Quantitative gait analysis allows not only the early detection of gait deficits and fall risk, but also of cognitive deficits. Early detection allows for timely implementation of targeted interventions to improve gait and/or cognition

Gait variability among healthy adults : low and high stride-to-stride variability are both a reflection of gait stability

BACKGROUND: It has been suggested that high stride-to-stride variability (STV) is a reflection of gait instability. However, both low and high STV has been shown in fallers and in nonfallers; therefore, the interpretation of STV of spatiotemporal gait parameters remains difficult. Thus, we sought to characterize and compare STV of spatial and temporal stride parameters among young and older healthy adults, and to determine the extent to which opposite results in STV could provide similar implications in terms of gait stability. METHODS: Mean values of coefficients of variation of spatiotemporal gait parameters were collected from 30 young adults (14 men and 16 women; mean age 28.1 +/- 6.0 years) and 33 older adults (2 men and 31 women; mean age 74.4 +/- 7.1 years) walking at self-chosen normal walking speed over a GAITRite System. RESULTS: An age-related increase in STV was only observed with stride width (p = 0.012), whereas increased stride length and stance time variability in older adults were related to decreased walking speed (p = 0.006 and p = 0.018). In addition, both low and high STV was found in both groups of subjects and the highest value was observed for stride width (p > 0.001). CONCLUSION: The two main implications of the present results are that decreased walking speed should be taken into account when exploring age-related effects on gait variability, and that both low and high spatiotemporal STV may reflect gait stability in healthy adults

Validity of the German Version of the Continuous-Scale Physical Functional Performance 10 Test

Background. The Continuous-Scale Physical Functional Performance 10 Test (CS-PFP 10) quantitatively assesses physical functional performance in older adults who have a broad range of physical functional ability. This study assessed the validity and reliability of the CS-PFP 10 German version. Methods. Forward-translations and backtranslations as well as cultural adaptions of the test were conducted. Participants were German-speaking Swiss community-dwelling adults aged 64 and older. Concurrent validity was assessed using Pearson correlation coefficients between CS-PFP 10 and gait velocity, Timed Up and Go Test, hand grip strength, SF-36 physical function domain, and Freiburger Physical Activity Questionnaire. Internal consistency was calculated by Cronbach’s alpha. Results. Backtranslation and cultural adaptions were accepted by the CS-PFP 10 developer. CS-PFP 10 total score and subscores (upper body strength, upper body flexibility, lower body strength, balance and coordination, and endurance) correlated significantly with all measures of physical function tested. Internal consistency was high (Cronbach’s alpha 0.95–0.98). Conclusion. The CS-PFP 10 German version is valid and reliable for measuring physical functional performance in German-speaking Swiss community-dwelling older adults. Quantifying physical function is essential for clinical practice and research and provides meaningful insight into physical functional performance of older adults. This trial is registered with ClinicalTrials.gov NCT01539200