Background
The previous studies have investigated causes of and risk factors for falls and impairment of functional capability in older adults. However, the biomechanical factors involved in ...functional performance and postural control, and the contribution of hip muscles, are still unknown.
Aims
The aim of the present study was to verify the association between the muscle function of hip abductors and adductors and static and dynamic balance, in a narrow base of support, in community-dwelling older adults.
Methods
Eighty-one older adults, including both women and men, were evaluated. Tandem gait and single-leg stance were used to assess static and dynamic balance, and an isokinetic dynamometer was used to analyze muscle function (peak torque and rate of torque development according to body weight). Data were analyzed by a multivariate linear regression test without adjustment and with adjustment using two models: adjustment I (sex) and adjustment II (age).
Results
There was a statistically significant association between peak torque of abductor in single-leg stance and tandem gait speed. The PT of hip adductors contributed to static balance performance, in a narrow base of support from the unadjusted data and from the adjusted data by sex.
Conclusion
The findings of the present study are relevant, because if deficits in balance and functionality in older adults can be linked to a decline in maximum muscle strength of hip abductors, this parameter can be treated to maintain independence in older adults for as long as possible.
•Grip strength can represent global muscle strength in community-dwelling older people.•Grip strength can be used to represent flexor muscles of the trunk, hip and knee.•There is no association ...between grip strength and ankle dorsiflexors.•Grip strength does not eliminate the need to specifically assess lower limb muscles.
There are still conflicting results regarding the association between grip and global muscle strength in older people. Therefore, the objective of the present study was to determine the association between grip strength and global muscle strength, as well as between grip strength and individual trunk, hip, knee and ankle muscle strengths.
Grip strength was assessed using a manual dynamometer, and trunk, hip, knee and ankle muscle strength with an isokinetic dynamometer, in order to obtain the global muscle strength variable, in 150 older men and women from the community. The association between grip and global muscle strength and between grip strength and the strength of each muscle group was determined through the Pearson correlation test, followed by multivariate linear regression adjusted for sex, age, body mass index, level of physical activity and number of comorbidities.
A positive significant association was found between grip strength and global muscle strength in older people (r = 0.690; β = 10.07; p < 0.001; R2 = 0.604), even after adjustment. There was also a low to moderate association between all the muscle groups and grip strength. However, when the model was adjusted, the relationship between grip strength and ankle dorsiflexor peak torque lost significance (p = 0.924).
Grip strength can represent global muscle strength in younger older people in the community, even when confounding variables are considered in the statistical model. However, grip strength does not eliminate the need for specific assessment of different muscle groups, when indicated.
The objective was to investigate the association between rate of torque development (RTD) and torque steadiness (TS) of the lower limb and the occurrence of prospective falls in community-dwelling ...older adults without falls in the previous year. One hundred older adults performed the tests to obtain the RTD and TS of the hip, knee, and ankle. New episodes of falls were monitored through telephone contact for a prospective period of 12 months. The association of RTD and TS with the occurrence of prospective falls was verified by multiple logistic regression adjusted for confounding variables. There was no association between RTD of hip, knee, and ankle and prospective falls. Only the TS at 50% of the peak torque of the hip flexors was associated with the occurrence of future falls (p = .023). Identifying modifiable risk factors for the first fall in older adults is essential for the development of adequate prevention programs.
The objective of the present study was to evaluate the association of hip muscle strength, dynamic balance and functional capacity in the older adults aged 60 to 79 years and older adults aged ...80 years and older. A total of 191 community-dwelling older adults participated in this study. Isometric muscle strength was quantified as the peak torque (PT), measured using an isokinetic dynamometer. Functional capacity was determined by the forward step test (ST) and the dynamic balance by the tandem gait (TG) test. The hip flexor, extensor, abductor and adductor PT in the older adults aged 60 to 79 years had a positive influence on the execution of the step test (p < 0.05). The peak adductor torque did not show a significant association with tandem gait (p = 0.649). In older adults aged 80 years and older, the peak adductor torque was the only one that showed an association with the performance of the ST (p = 0.001) and TG (p = 0.024) tests. The hip adductors may have a higher contribution in adults aged 80 years and older during the execution of clinical tests. These findings are relevant to clinical practice as they can help in the development of appropriate physical exercise programs targeting older adults of different age groups.
With increases in life expectancy, it is important to understand the influence of aging on gait, given that this activity is related to the independence of older adults and may help in the ...development of health strategies that encourage successful aging in all phases of this process.
To compare gait parameters with usual and fast speeds for independent and autonomous older adults throughout the aging process (60 to 102 years old), and also to identify which of the gait variables are best for identifying differences across the different age groups.
Two hundred older adults aged between 60 and 102 years were evaluated. The sample was divided into 3 age groups: 60 to 79 years, 80 to 89 years and 90 years and over. The analyzed gait variables were: speed (meters/s), cadence (steps/min), stride time (seconds), step length (centimeters), double support (percentage of the gait cycle), swing (percentage of the gait cycle), step length variability (CoV%) and stride time variability (CoV%).
Group comparison regarding usual gait and fast gait revealed a significant difference in all gait variables. In addition, it can be seen that variables such as gait speed and step length showed greater effect sizes in intergroup comparison (usual gait: 0.48 and 0.47; fast gait: 0.36 and 0.40; respectively), possibly showing that these variables can better detect the changes observed with increasing age.
There are differences in the gait performance of older adults from different age groups for usual and fast gait speeds, which is more evident regarding gait speed and step length variables. We recommend the use of usual gait for the identification of the effects of aging because, besides showing a higher effect size values it is more comfortable and requires less effort from older subjects.
•Physiological age has a greater influence on gait than chronological age in younger older adults.•Eighty years or more of chronological age may be a determining factor for gait alterations.•Age-related changes in gait variables are more pronounced in gait speed and step length.
Background and purpose
The pathophysiology of Parkinson's disease (PD) negatively affects brain network connectivity, and in the presence of brain white matter hyperintensities (WMHs) cognitive and ...motor impairments seem to be aggravated. However, the role of WMHs in predicting accelerating symptom worsening remains controversial. The objective was to investigate whether location and segmental brain WMH burden at baseline predict cognitive and motor declines in PD after 2 years.
Methods
Ninety‐eight older adults followed longitudinally from Ontario Neurodegenerative Diseases Research Initiative with PD of 3–8 years in duration were included. Percentages of WMH volumes at baseline were calculated by location (deep and periventricular) and by brain region (frontal, temporal, parietal, occipital lobes and basal ganglia + thalamus). Cognitive and motor changes were assessed from baseline to 2‐year follow‐up. Specifically, global cognition, attention, executive function, memory, visuospatial abilities and language were assessed as were motor symptoms evaluated using the Movement Disorder Society Unified Parkinson's Disease Rating Scale Part III, spatial–temporal gait variables, Freezing of Gait Questionnaire and Activities Specific Balance Confidence Scale.
Results
Regression analysis adjusted for potential confounders showed that total and periventricular WMHs at baseline predicted decline in global cognition (p < 0.05). Also, total WMH burden predicted the decline of executive function (p < 0.05). Occipital WMH volumes also predicted decline in global cognition, visuomotor attention and visuospatial memory declines (p < 0.05). WMH volumes at baseline did not predict motor decline.
Conclusion
White matter hyperintensity burden at baseline predicted cognitive but not motor decline in early to mid‐stage PD. The motor decline observed after 2 years in these older adults with PD is probably related to the primary neurodegenerative process than comorbid white matter pathology.
Reference values for the Balance Evaluation Systems Test (BESTest) and the Mini-Balance Evaluation Systems Test (Mini-BESTest) need to be established to predict falls in older adults during every ...stage of aging. The purpose of this study was to determine the cutoff scores for the BESTest and the Mini-BESTest for community-dwelling older adults in order to predict fall risk.
A total of 264 older adults, of both sexes, between the ages of 60 and 102 years, were divided into 4 groups according to age range. After evaluation, participants received telephone follow-up for 6 months to record the number of fall episodes. To define the reference values of the tests in relation to fall risk prediction, a receiver operating characteristic curve was drawn to identify the area under the curve and the sensitivity and specificity of the tests. Statistical analyses were done using SPSS (Version 16.0-SPSS Inc) with a significance level of 5% (P ≤ .05).
The cutoff scores to identify older adults with fall risk according to the BESTest and the Mini-BESTest in the different age groups were 99 and 25 points, respectively, for people 60 to 69 years of age, 92 and 23 points for the age group of 70 to 79 years, 85 and 22 points for people 80 to 89 years of age, and 74 and 17 points for people 90 years of age or older.
The BESTest and the Mini-BESTest are good tools for predicting fall risk in the 6 months following an initial evaluation in community-dwelling Brazilian older adults. The study also determined that cutoff values vary for different age groups.
Abstract
Objective
The objective of this study was to determine the accuracy of 3 clinical tests (lateral step LS, tandem gait TG, and single-leg stance SS) in identifying older women with reduced ...hip abductor muscle strength and to determine the post-test probability of each test and of their combination in changing the certainty of diagnosis.
Methods
In this cross-sectional study, a total of 123 older women received clinical testing to obtain the variables LS height, time for TG execution, percentage of errors in TG, and time of permanence on SS and were tested for isometric hip abductor peak torque using an isokinetic dynamometer. Only the dominant lower limb was evaluated. Multiple linear regression analysis with adjustment was performed to determine the association among variables, followed by the receiver operating characteristic curve to identify clinical variables that can discriminate older women with reduced abductor muscle strength. Post-test probability was then calculated based on the receiver operating characteristic curve data.
Results
Although the 4 clinical variables showed correlation with abductor peak torque, only LS and TG time were able to discriminate reduced abductor muscle strength with low accuracy (area under the curve was between 0.5 and 0.7). However, the combination of LS and TG time increased post-test probability from 47% (prevalence of weakness in the population) to 76% when both tests were positive and reduced it from 47% to 18% when both tests were negative.
Conclusion
The combination of the LS test and TG time is useful for the indirect assessment of hip abductor strength in community-dwelling older women.
Impact
Hip abductor muscle strength is extremely important for function in older women. This study presents clinicians with simple, fast, and inexpensive methods for assessing hip abductor muscle strength.
•Hip abductor fatigue negatively affected tests that involve unipodal support.•The single limb stance test was the most affected task by hip abductor fatigue.•Small limitation of functional tests ...suggests the presence of postural compensations.
Hip abductor muscles are important for the maintenance of postural stability, mainly on the mediolateral direction and unipodal support conditions. The objective of the present study was to evaluate the effect of unilateral induced fatigue of hip abductor muscles on balance and functional capacity of older women.
The study included physically independent women aged 60–75 years. We assessed static balance with the single limb stance test (SLS) and evaluated functional capacity with the maximum gait speed (MGS) and step test (ST). We ran the protocol of hip abductor muscle fatigue with a Biodex isokinetic dynamometer. Assessment of balance and functional capacity happened before and after the muscle fatigue protocol. We applied the t-test for repeated measures to determine whether unilateral hip abductor muscle fatigue influences the performance in the tests (SLS, MGS and ST).
The protocol of hip abductor muscle fatigue negatively affected all three evaluated tasks: SLS (p = 0.000), ST (p = 0.000) and MGS (p = 0.000). However, the single limb stance test was the most task affected (effect size = 0.51, pre- and post-fatigue difference = 28.1 %).
After the unilateral muscle fatigue of hip abductors, we observed the worst performance on clinical tests, mainly regarding the SLS test, which shows the involvement of hip abductors during usual motor tasks. However, the small magnitude of the limitation of functional tests (MGS and ST) suggests the presence of postural compensations.
•Discussion about changes gait kinematics in older faller during dual-task gait.•Older fallers and non-fallers had similar abnormalities on gait during dual task gait.•Cognitive dual task gait ...challenges more older adults than motor dual task gait.
Human gait has been widely investigated under dual-task conditions because it has been demonstrated to be an important way to uncover differences in gait biomechanics between older fallers and non-fallers. However, exactly how simultaneous tasks affect the kinematics of walking remains unclear. In the present study, gait kinematic properties of older fallers and non-fallers were compared under cognitive and motor dual-task conditions. The gait kinematic properties of interest were recorded under three different conditions: walking at preferred speed, walking when performing a cognitive task (naming animals), and walking when performing a motor task (transferring a coin from one pocket to the other). The following variables were analyzed: gait speed, cadence, stride time, step length, single support, stride time variability, and the dual-task cost. In addition, functional balance was evaluated by means of the Balance Evaluation – Systems Test (BESTest). Two-way repeated-measures ANOVAs revealed significant main effects of walking conditions. However, no significant main effects of group (fallers vs. non-fallers) and no significant interaction effects between group and walking condition were observed. The BESTest revealed that functional balance in fallers was worse than in non-fallers. The cognitive task leads to more significant changes in gait kinematics than does a motor task and the step length and stride time variability were variables more sensitive to that cognitive influence.
