Lower extremity muscle quality and gait variability in older adults

Exploring the Promising Impact of Pulmonary Rehabilitation on Gait and Balance in Patients With COPD: A Systematic Review and Meta-Analysis

PURPOSE

Chronic obstructive pulmonary disease (COPD) is commonly associated with respiratory difficulties, but it also presents with musculoskeletal problems. The objective of this systematic review and meta-analysis was to evaluate the effects of pulmonary rehabilitation (PR) on balance and gait in patients with COPD.

REVIEW METHODS

We conducted a comprehensive search of 4 databases, including PubMed, Google Scholar, Science Direct, and Web of Science, from inception to November 2023. The review included studies reporting the association between COPD status and balance and gait using PR. Two independent reviewers examined the titles and abstracts, extracted the data using a standardized form, and assessed the risk of bias of the included articles.

SUMMARY

A total of 14 studies with 320 patients in the study groups and 188 controls were included in the analysis. The risk of bias in the included studies was medium to high. The results showed that PR non-statistically significantly improved balance, as demonstrated by moderate effect sizes in the Timed Up and Go (standardized mean difference [SMD] = 0.1: 95% CI, -1.41 to 1.69) and Berg Balance Scale (SMD = -0.39: 95% CI, -1.30 to 0.53). However, the impact of PR on gait function was less clear, with mixed results. The study findings highlight the positive but non-significant effects of PR on balance in individuals with COPD. The results suggest that PR programs could include exercises that target balance improvement to enhance the overall quality of patients. However, further research is needed to determine the optimal duration and intensity of these exercises to achieve maximum benefits for patients with COPD.

Increased Variability in Lower Limb Muscle Activation Is Observed with Increasing Walking Speed in Fall-Risk Older Adults

This study is a cross-sectional study and aims to determine the differences in lower limb muscle activation and variability at preferred, slow, and fast walking speeds according to age and fall risk. We divided 301 participants into groups based on fall risk (fall-risk vs. non-fall-risk). We measured muscle activation and its coefficients of variation (CV) for the rectus femoris (RF), biceps femoris (BF), tibialis anterior (TA), and medial gastrocnemius muscle (GCM) at speeds 20% slower, 20% faster, and 40% faster than the preferred speed (PS). When compared by fall risk, fall-risk older adults had significantly lower GCM activity and higher CVs of RF, BF, TA, and GCM in PS. With changes in gait speed, fall-risk older adults had significantly increased CVs of RF, BF, and GCM. Our findings provide new evidence that variability rather than muscle activity increases with walking speed in older adults at risk of falls, highlighting the importance of decreasing muscle activity variability in preventing fall risk.

Walking performance differs between people with multiple sclerosis who perform distinct types of exercise

Aim: To determine whether walking performance differed between people with multiple sclerosis (MS) who performed distinct types, volumes and intensities of exercise.Materials & methods: Forty-five people with relapsing-remitting MS performed two trials of the 2-min walk test, one at a preferred speed and another at a fast speed. Gait metrics were measured by wireless inertial sensors. Participants reported the type (aerobic, resistance), volume and intensity of exercise performed.Results: Walking speed reserve and gait variability were better in participants who performed combined aerobic and resistance exercises compared with those who performed aerobic-only exercise.Conclusion: Walking performance differs in people with mild MS disability based on the type and volume of exercise performed.

Machine learning approach to classifying declines of physical function and muscle strength associated with cognitive function in older women: gait characteristics based on three speeds

Background

The aging process is associated with a cognitive and physical declines that affects neuromotor control, memory, executive functions, and motor abilities. Previous studies have made efforts to find biomarkers, utilizing complex factors such as gait as indicators of cognitive and physical health in older adults. However, while gait involves various complex factors, such as attention and the integration of sensory input, cognitive-related motor planning and execution, and the musculoskeletal system, research on biomarkers that simultaneously considers multiple factors is scarce. This study aimed to extract gait features through stepwise regression, based on three speeds, and evaluate the accuracy of machine-learning (ML) models based on the selected features to solve classification problems caused by declines in cognitive function (Cog) and physical function (PF), and in Cog and muscle strength (MS).

Methods

Cognitive assessments, five times sit-to-stand, and handgrip strength were performed to evaluate the Cog, PF, and MS of 198 women aged 65 years or older. For gait assessment, all participants walked along a 19-meter straight path at three speeds [preferred walking speed (PWS), slower walking speed (SWS), and faster walking speed (FWS)]. The extracted gait features based on the three speeds were selected using stepwise regression.

Results

The ML model accuracies were revealed as follows: 91.2% for the random forest model when using all gait features and 91.9% when using the three features (walking speed and coefficient of variation of the left double support phase at FWS and the right double support phase at SWS) selected for the Cog+PF+ and Cog-PF- classification. In addition, support vector machine showed a Cog+MS+ and Cog-MS- classification problem with 93.6% accuracy when using all gait features and two selected features (left step time at PWS and gait asymmetry at SWS).

Conclusion

Our study provides insights into the gait characteristics of older women with decreased Cog, PF, and MS, based on the three walking speeds and ML analysis using selected gait features, and may help improve objective classification and evaluation according to declines in Cog, PF, and MS among older women.

Research of Global Tilt and Functional Independence: Insights into Spinal Health of Older Women

Spinal alignment intricately influences functional independence, particularly in older women with osteopenia experiencing mild neck and back pain. This study elucidates the interplay between spinal alignment, bone mineral density (BMD), and muscle strength in elderly women presenting with mild neck and back pain. Focusing on a cohort of 189 older women, we examined the associations among global tilt (GT), coronal and sagittal alignment, BMD, grip strength, and functional independence as gauged by the Barthel index. Our findings indicate significant associations between functional capacity and grip strength, bone density, GT, and pelvic tilt (PT). Elderly women with a Barthel Index above 80 demonstrated higher grip strength and better bone quality, reflected by less negative average T scores. These individuals also exhibited lower values of GT and PT, suggesting a better sagittal alignment compared to those with a Barthel index of 80 or below. The results highlight that deviations in GT and PT are significantly associated with decreased functional independence. These insights emphasize the importance of maintaining optimal spinal alignment and muscle strength to support functional independence in elderly women. This study underscores the potential for targeted interventions that improve postural stability and manage pain effectively in this vulnerable population.

How Healthy Older Adults Enact Lateral Maneuvers While Walking

BACKGROUND

Walking requires frequent maneuvers to navigate changing environments with shifting goals. Humans accomplish maneuvers and simultaneously maintain balance primarily by modulating their foot placement, but a direct trade-off between these two objectives has been proposed. As older adults may rely more on foot placement to maintain lateral balance, they may be less able to adequately adapt stepping to perform lateral maneuvers.

RESEARCH QUESTION

How do older adults adapt stepping to enact lateral lane-change maneuvers, and how do physical and perceived ability influence their task performance?

METHODS

Twenty young (21.7 ± 2.6 yrs) and 18 older (71.6 ± 6.0 yrs) adults walked on a motorized treadmill in a virtual environment. Following an audible and visual cue, participants switched between two parallel paths, centered 0.6 m apart, to continue walking on their new path. We quantified when participants initiated the maneuver following the cue, as well as their step width, lateral position, and stepping variability ellipses at each maneuver step.

RESULTS

Young and older adults did not differ in when they initiated the maneuver, but participants with lower perceived ability took longer to do so. Young and older adults also did not exhibit differences in step width or lateral positions at any maneuver step, but participants with greater physical ability reached their new path faster. While only older adults exhibited stepping adaptations prior to initiating the maneuver, both groups traded off stability for maneuverability to enact the lateral maneuver.

SIGNIFICANCE

Physical and perceived balance ability, rather than age per se, differentially influenced maneuver task performance. Humans must make decisions related to the task of walking itself and do so based on both physical and perceived factors. Understanding and targeting these interactions may help improve walking performance among older adults.

Minimal Detectable Changes in the Five Times Sit-to-Stand Test in Older Japanese Adults with Sarcopenia Requiring Long-Term Care

Background and Objectives: Although the importance of sarcopenia control has been suggested, there are no minimal detectable change (MDC) studies of older adults with sarcopenia, to our knowledge, and the criteria for determining the effectiveness of interventions are unknown. The purpose of this study was to calculate the MDC in the five times sit-to-stand test (FTSST) in older Japanese adults with sarcopenia and use it as an index to determine the effectiveness of future interventions. Materials and Methods: This was a cross-sectional study conducted in January and February 2023. The participants of this study were older Japanese adults using daycare rehabilitation. Thirty-eight participants performed the FTSST twice a week. Grip strength, walking speed, and skeletal muscle mass were measured to determine the presence of sarcopenia. The diagnosis of sarcopenia was defined as low skeletal muscle mass and low muscle strength and/or low physical function, based on the Asian Working Group for Sarcopenia 2019 diagnostic criteria. Participants were further classified as sarcopenic or non-sarcopenic. Intraclass correlation coefficients (ICCs) and MDCs were calculated for the overall, sarcopenia, and non-sarcopenia groups using the two FTSST measures. The average and difference of the two variables were used to calculate the MDC. Results: Overall, the ICC (1,1) was 0.94, MDC was 2.87 s, and MDC% was 23.3%. The sarcopenia group had an ICC (1,1) of 0.93, MDC of 3.12 s, and MDC% of 24.0%. The non-sarcopenia group had an ICC (1,1) of 0.95, MDC of 2.25 s, and MDC% of 19.2%. Conclusions: Despite the limitation of the data being only from this study population, we found that a change of ≥3.12 s or ≥24.0% in the FTSST of older adults with sarcopenia was clinically meaningful and may help to determine the effectiveness of sarcopenia treatment. The improvement or decline in older Japanese adults with sarcopenia should be determined by changes in the FTSST over a longer period of time than that for other conditions.

A machine learning approach to identify important variables for distinguishing between fallers and non-fallers in older women

Falls are a significant ongoing public health concern for older adults. At present, few studies have concurrently explored the influence of multiple measures when seeking to determine which variables are most predictive of fall risks. As such, this cross-sectional study aimed to identify those functional variables (i.e. balance, gait and clinical measures) and physical characteristics (i.e. strength and body composition) that could best distinguish between older female fallers and non-fallers, using a machine learning approach. Overall, 60 community-dwelling older women (≥65 years), retrospectively classified as fallers (n = 21) or non-fallers (n = 39), attended three data collection sessions. Data (281 variables) collected from tests in five separate domains (balance, gait, clinical measures, strength and body composition) were analysed using random forest (RF) and leave-one-variable-out partial least squares correlation analysis (LOVO PLSCA) to assess variable importance. The strongest discriminators from each domain were then aggregated into a multi-domain dataset, and RF, LOVO PLSCA, and logistic regression models were constructed to identify the important variables in distinguishing between fallers and non-fallers. These models were used to classify participants as either fallers or non-fallers, with their performance evaluated using receiver operating characteristic (ROC) analysis. The study found that it is possible to classify fallers and non-fallers with a high degree of accuracy (e.g. logistic regression: sensitivity = 90%; specificity = 87%; AUC = 0.92; leave-one-out cross-validation accuracy = 63%) using a combination of 18 variables from four domains, with the gait and strength domains being particularly informative for screening programmes aimed at assessing falls risk.

Spatial characteristics of reactive stepping among people living with chronic incomplete spinal cord injury

Objective: Compare the spatial characteristics of reactive stepping between individuals with chronic motor incomplete spinal cord injuries (iSCI) and able-bodied (AB) individuals.Design: Cross sectional.Setting: Lyndhurst Centre.Participants: Twelve individuals with iSCI (3 males, 53.6 ± 15.2 years old) and 11 age- and sex-matched AB individuals (3 males, 54.8 ± 14.0 years old).Interventions: The Lean-and-Release test was used to elicit reactive stepping. A horizontal cable, attached at waist height, was released when 8-12% body weight was supported in a forward lean position. Participants underwent up to 10 Lean-and-Release trials in a session. Kinematic and kinetic data were recorded.Outcome measures: The length, width and height of the first reactive step of each trial were calculated. Standard deviation between trials was calculated to represent the variability in step length, width and height within a participant. Among participants with iSCI, correlation coefficients were used to explore the relationship between step length and width variability and (1) Lean-and-Release test behavioral responses, (2) 3-month fall history, and (3) lower extremity strength.Results: Step length (P = 0.94), width (P = 0.52) and height (P = 0.97), normalized for participant height, did not differ between groups. Participants with iSCI showed greater variability in step length (P = 0.02) and width (P = 0.01), but not height (P = 0.32). No correlation was found between step length or width variability and behavioral responses, 3-month fall history, or lower extremity strength.Conclusions: Individuals with iSCI showed increased variability in length and width of reactive stepping compared to AB individuals, which may contribute to their impaired ability to execute single-step reactive responses.Trial registration: ClinicalTrials.gov identifier: NCT02960178.

The Effects of 12-Week Dual-Task Physical-Cognitive Training on Gait, Balance, Lower Extremity Muscle Strength, and Cognition in Older Adult Women: A Randomized Study

This study aims to investigate the effects of dual-task physical-cognitive the training on body balance (BB), gait performance (GP), lower limb muscle strength (LEMS), and cognitive performance (CP) in a group of cognitively normal older adult women (n = 44; 66.20 ± 4.05 years). Of these, 22 were randomly allocated to the dual-task training (DT) group, and 22 participated in the control group (CG). Assessments were performed at baseline, after 12 weeks of intervention, and at the end of 12 weeks of follow-up, using the following instruments: Timed Up & Go (TUG), Timed Up & Go manual (TUGm), Timed Up & Go cognitive (TUGc), Balance Test (TEC), sit-to-stand test (STS), and verbal fluency test (VF). After 12 weeks of DT training, participants showed a significant time × group interaction in all motor assessments (BB, GP, LEMS), as well as in three cognitive tests (VF-grouping, VF-exchange, VF-total). No time-group interaction effect was indicated for the VF-category test. At all evaluation times, CG members maintained constant physical and cognitive performance. We conclude that 12 weeks of physical-cognitive DT training was effective in promoting BB, GP, and LEMS, as well as CP in cognitively normal older adult women, with lasting effects up to 12 weeks after the intervention.

How Healthy Older Adults Enact Lateral Maneuvers While Walking

Background

Walking requires frequent maneuvers to navigate changing environments with shifting goals. Humans accomplish maneuvers and simultaneously maintain balance primarily by modulating their foot placement, but a direct trade-off between these two objectives has been proposed. As older adults rely more on foot placement to maintain lateral balance, they may be less able to adequately adapt stepping to perform lateral maneuvers.

Research Question

How do older adults adapt stepping to enact lateral lane-change maneuvers, and how do physical and perceived ability influence their task performance?

Methods

Twenty young (21.7 ± 2.6 yrs) and 18 older (71.6 ± 6.0 yrs) adults walked on a motorized treadmill in a virtual environment. Following an audible and visual cue, participants switched between two parallel paths, centered 0.6m apart, to continue walking on their new path. We quantified when participants initiated the maneuver following the cue, as well as their step width, lateral position, and stepping variability ellipses at each maneuver step.

Results

Young and older adults did not differ in when they initiated the maneuver, but participants with lower perceived ability took longer to do so. Young and older adults also did not exhibit differences in step width or lateral positions at any maneuver step, but participants with greater physical ability reached their new path faster. While only older adults exhibited stepping adaptations prior to initiating the maneuver, both groups traded-off stability for maneuverability to enact the lateral maneuver.

Significance

Physical and perceived balance ability, rather than age per se, differentially influenced maneuver task performance. Humans must make decisions related to the task of walking itself and do so based on both physical and perceived factors. Understanding and targeting these interactions may help improve walking performance among older adults.

Association of preoperative muscle composition of the lower extremity with gait function after total knee arthroplasty

BACKGROUND

Limitations of gait function persist in some patients with knee osteoarthritis after total knee arthroplasty. This study aimed to identify preoperative muscle composition variables of the operated limb associated with postoperative gait function.

METHODS

Longitudinal data from 45 patients who underwent unilateral primary total knee arthroplasty were retrospectively analyzed. Timed Up-and-Go test and gait speed were measured preoperatively and at 3 and 6 months postoperatively. Preoperative muscle composition in the glutei medius and minimus, the quadriceps, the hamstrings, and combination of the hamstrings and quadriceps were evaluated by computed tomography. The area ratio of the individual muscle composition to the total muscle was calculated. The factors associated with Timed Up-and-Go test and gait speed were identified using stepwise regression analysis.

RESULTS

Shorter Timed Up-and-Go test and faster gait speed at each time point correlated with higher lean muscle mass area of the total hamstrings, higher area ratio of lean muscle mass to the total hamstrings or to combination of the hamstrings and quadriceps, and lower area ratio of low density lean tissue or intramuscular adipose tissue to the total hamstrings. Shorter Timed Up-and-Go test at each time point also correlated with higher combined area of lean muscle mass of the hamstrings and quadriceps. Faster gait speed at each time point additionally correlated with lower area ratio of intramuscular fat to the total hamstrings and lower area ratio of lean tissue mass or intramuscular adipose tissue to combination of the hamstrings and quadriceps. Regression analysis using the significant muscle composition variables revealed that the area ratio of lean muscle mass to the total hamstrings was the only predictor of Timed Up-and-Go test and gait speed after operation.

CONCLUSIONS

Preoperative area ratio of ipsilateral lean muscle mass to the total hamstrings could predict gait function after total knee arthroplasty.

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.

A systematic review of chiropractic care for fall prevention: rationale, state of the evidence, and recommendations for future research

BACKGROUND

Falls in older adults are a significant and growing public health concern. There are multiple risk factors associated with falls that may be addressed within the scope of chiropractic training and licensure. Few attempts have been made to summarize existing evidence on multimodal chiropractic care and fall risk mitigation. Therefore, the broad purpose of this review was to summarize this research to date. BODY: Systematic review was conducted following PRISMA guidelines. Databases searched included PubMed, Embase, Cochrane Library, PEDro, and Index of Chiropractic Literature. Eligible study designs included randomized controlled trials (RCT), prospective non-randomized controlled, observational, and cross-over studies in which multimodal chiropractic care was the primary intervention and changes in gait, balance and/or falls were outcomes. Risk of bias was also assessed using the 8-item Cochrane Collaboration Tool. The original search yielded 889 articles; 21 met final eligibility including 10 RCTs. One study directly measured the frequency of falls (underpowered secondary outcome) while most studies assessed short-term measurements of gait and balance. The overall methodological quality of identified studies and findings were mixed, limiting interpretation regarding the potential impact of chiropractic care on fall risk to qualitative synthesis.

CONCLUSION

Little high-quality research has been published to inform how multimodal chiropractic care can best address and positively influence fall prevention. We propose strategies for building an evidence base to inform the role of multimodal chiropractic care in fall prevention and outline recommendations for future research to fill current evidence gaps.

Lifestyle factors associated with muscle quality in community-dwelling older people with type 2 diabetes in Japan and Taiwan: a cross-sectional study

BACKGROUND

Type 2 diabetes mellitus (T2DM), common in older people, is an important reason for muscle loss in Japanese and Taiwanese populations. However, little is known about the association between lifestyle behaviours and muscle quality. We aimed to compare the lifestyle behaviours of Japanese and Taiwanese older adults with T2DM and to the identify lifestyle factors associated with muscle quality.

METHODS

This cross-sectional study was conducted among community-dwelling individuals with T2DM aged ≥65 years in Taiwan and Japan. Totally, 114 Japanese and 226 Taiwanese participants were enrolled in the study. Outcomes were measured by blood biochemical examinations, body composition analyses and structured self-reported questionnaires to assess lifestyle behaviours and muscle quality. Linear regression models were used to examine the relationship between lifestyle factors and muscle quality using SPSS version 27.0 with a statistical significance level of P < 0.05.

RESULTS

Japanese subjects were more likely to be smokers and alcohol consumers, and they were less likely to have well-balanced diets and engage in more physical activity as compared to Taiwanese subjects. The muscle quality in the Japanese subjects was significantly poorer than that in the Taiwanese subjects. Physical activity, dietary habits and smoking were associated with muscle quality, after adjusting for age, gender and body mass index.

CONCLUSIONS

Physical activity of insufficient intensity, unhealthy dietary habits and smoking could be risk factors for poor muscle quality. These findings can contribute to the development of effective strategies to improve muscle quality in community-dwelling older Asian people with T2DM.

Association of Muscle Mass, Muscle Strength, and Muscle Function with Gait Ability Assessed Using Inertial Measurement Unit Sensors in Older Women

Aging-related muscle atrophy is associated with decreased muscle mass (MM), muscle strength (MS), and muscle function (MF) and may cause motor control, balance, and gait pattern impairments. This study determined associations of three speed-based gait variables with loss of MM, MS, and MF in older women. Overall, 432 older women aged ≥65 performed appendicular skeletal muscle, handgrip strength, and five times sit-to-stand test to evaluate MM, MS, and MF. A gait test was performed at three speeds by modifying the preferred walking speed (PWS; slower walking speed (SWS); faster-walking speed (FWS)) on a straight 19 m walkway. Stride length (SL) at PWS was significantly associated with MM. FWS and coefficient of variance (CV) of double support phase (DSP) and DSP at PWS showed significant associations with MS. CV of step time and stride time at SWS, FWS, and single support phase (SSP) at PWS showed significant associations with MF. SL at PWS, DSP at FWS, CV of DSP at PWS, stride time at SWS, and CV of SSP at PWS showed significant associations with composite MM, MS, and MF variables. Our study indicated that gait tasks under continuous and various speed conditions are useful for evaluating MM, MS, and MF.

Muscle Quality of Knee Extensors Based on Several Types of Force in Multiple Sclerosis Patients with Varying Degrees of Disability

Background and Objectives: Multiple sclerosis (MS) tends to affect muscle performance, mainly in the lower extremities. The degree of disability is associated with the loss of strength and muscle mass, to varying extents. Muscle quality (MQ) expresses the amount of force produced relative to the activated muscle mass. The purpose of this study was to compare the MQ of the knee extensors in the main manifestations of strength (isometric, dynamic strength, and power) among patients with differing degrees of neurological disability and evolutionary forms of the disease. We also establish reference values for MQ in MS patients (pwMS). Materials and Methods: In total, 250 pwMS were evaluated according to the Expanded Disability Status Scale (EDSS). The maximum dynamic and isometric forces and muscle power manifested a load of 60% of the maximum dynamics of the knee extensors. The lean mass of the thigh and hip was determined by densitometry, and the MQ was calculated for the three types of force evaluated. Results: The pwMS with relapsing remitting MS (RRMS) presented isometric MQ values that were 15.8% better than those of pwMS with primary progressive MS (PPMS) and 13.8% better than those of pwMS with secondary progressive MS (SPMS). For pwMS with SPMS, the dynamic MQ was 16.7% worse than that of patients with RRMS, while the power MQ was 29.5% worse. By degree of disability (<4 >7.5 EDSS score), patients with better MQ had mild EDSS scores, and patients with severe EDSS scores had 24.8%, 25.9%, and 40.3% worse isometric, dynamic, and power MQ scores, respectively, than those with RRMS. Based on these results, reference values for MQ in pwMS were established. Conclusions: The pwMS with different types of MS do not show differences in lean mass or strength but do show differences in MQ. In pwMS with different EDSS grades, there are no differences in lean mass, but there are differences in strength based on MQ, especially power MQ.

Aerobic capacity and skeletal muscle characteristics in glycogen storage disease IIIa: an observational study

Background

Individuals with glycogen storage disease IIIa (GSD IIIa) (OMIM #232400) experience muscle weakness and exercise limitation that worsen through adulthood. However, normative data for markers of physical capacity, such as strength and cardiovascular fitness, are limited. Furthermore, the impact of the disease on muscle size and quality is unstudied in weight bearing skeletal muscle, a key predictor of physical function. We aim to produce normative reference values of aerobic capacity and strength in individuals with GSD IIIa, and to investigate the role of muscle size and quality on exercise impairment.

Results

Peak oxygen uptake (V̇O₂peak) was lower in the individuals with GSD IIIa than predicted based on demographic data (17.0 (9.0) ml/kg/min, 53 (24)% of predicted, p = 0.001). Knee extension maximum voluntary contraction (MVC) was also substantially lower than age matched predicted values (MVC: 146 (116) Nm, 57% predicted, p = 0.045), though no difference was found in MVC relative to body mass (1.88 (2.74) Nm/kg, 61% of predicted, p = 0.263). There was a strong association between aerobic capacity and maximal leg strength (r = 0.920; p = 0.003). Substantial inter-individual variation was present, with a high physical capacity group that had normal leg strength (MVC), and relatively high V̇O₂peak, and a low physical capacity that display impaired strength and substantially lower V̇O₂peak. The higher physical capacity sub-group were younger, had larger Vastus Lateralis (VL) muscles, greater muscle quality, undertook more physical activity (PA), and reported higher health-related quality of life.

Conclusions

V̇O₂peak and knee extension strength are lower in individuals with GSD IIIa than predicted based on their demographic data. Patients with higher physical capacity have superior muscle size and structure characteristics and higher health-related quality of life, than those with lower physical capacity. This study provides normative values of these important markers of physical capacity.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13023-022-02184-1.

The Effect of Body Composition on Gait Variability Varies with Age: Interaction by Hierarchical Moderated Regression Analysis

Although body composition has been found to affect various motor functions (e.g., locomotion and balance), there is limited information on the effect of the interaction between body composition and age on gait variability. The purpose of this study was to determine the effect of body composition on gait according to age. A total of 80 men (40 young and 40 older males) participated in the experiment. Body composition was measured using bioelectrical impedance analysis (BIA), and gait parameters were measured with seven-dimensional inertial measurement unit (IMU) sensors as each participant walked for 6 min at their preferred pace. Hierarchical moderated regression analysis, including height as a control variable and age as a moderator variable, was performed to determine whether body composition could predict gait parameters. In young males, stride length decreased as body fat percentage (BFP) increased (R² = 13.4%), and in older males, stride length decreased more markedly as BFP increased (R² = 26.3%). However, the stride length coefficient of variation (CV) of the older males increased significantly as BFP increased (R² = 16.2%), but the stride length CV of young males did not change even when BFP increased. The increase in BFP was a factor that simultaneously caused a decrease in gait performance and an increase in gait instability in older males. Therefore, BFP is more important for a stable gait in older males.

Effects of age, physical and self-perceived balance abilities on lateral stepping adjustments during competing lateral balance tasks

BACKGROUND

Daily walking paths exhibit varying environment features and require continuous adjustments to locomotor trajectories. Humans maintain lateral balance while navigating paths by modifying stepping in accordance with changing side-to-side path limitations (e.g. path width, lateral location). These processes are influenced by one's actual physical ability to maintain balance, as well as their self-perceived balance ability. Older adults experience decreases in each of these abilities, which may alter their capacity to execute appropriate lateral stepping adaptations.

RESEARCH QUESTION

How do age, physical and self-perceived balance abilities interact to influence lateral stepping adaptations of older adults walking in complex environments with dynamic lateral path features?

METHODS

Twenty young (age mean ± SD: 21.7 ± 2.6) and 18 older adults (age mean ± SD: 71.6 ± 6.0) walked on an instrumented treadmill in a virtual-reality system. Participants adjusted lateral stepping during two competing lateral balance sub-tasks that manipulated either path width or location. Participants began walking on a gradually-narrowing path (sub-task A), then decided when/ how to laterally maneuver to an adjacent path (sub-task B). Recorded path characteristics were used to quantify spatial thresholds for stepping error onset and sub-task exchange.

RESULTS

Older adults made sub-task A stepping errors on wider paths and exchanged sub-tasks earlier. These differences were not directly attributed to age. Statistical path analyses revealed that physical balance ability mediated age effects on stepping error onset, while self-perceived balance ability mediated age effects on sub-task exchange. Both age groups exchanged sub-tasks when stepping accuracy likelihoods were similar and high, ∼90 %.

SIGNIFICANCE

This work demonstrates important mechanisms for how age, via degradation of physical and self-perceived balance abilities, indirectly and differentially influences navigation of competing lateral balance tasks. Mediating physical and perceptual factors are potential targets for improving older adults' navigation of complex environments.

Fast gait spatiotemporal parameters in adults and association with muscle strength - The Yishun study

BACKGROUND

There is limited data on fast gait speed and spatial-temporal parameters across age groups among Asian adults, and the associations between upper and lower extremity muscle strength with gait.

RESEARCH QUESTION

What values characterise fast gait spatiotemporal parameters across the age groups of an Asian population? Are hand grip strength (HGS) and knee extension strength (KES) associated with fast gait speed and spatiotemporal parameters?

METHODS

Healthy community-living adults between 21-90 years (n = 487) were recruited. Fast gait was assessed using a 6 m instrumented walkway, and spatiotemporal parameters including variability for fast gait speed, stride length, stride width, stride time, stance time, swing time, single support time and double support time were analysed. Maximum HGS and KES were also assessed. Linear regression modelling was used to explore the association of HGS and KES with fast gait speed, spatiotemporal parameters and their variability.

RESULTS

Age reduced fast gait speed and stride length, but increased stride width, stance time, stride time and double support time. Age increased all investigated gait variabilities except stride width variability. Gender differences were observed for all gait features except for fast gait speed and double support time. Both HGS and KES were positively associated with fast gait speed in both young and old adults. KES was positively associated with spatiotemporal variations in stride length, stride time, stance time and double support time. HGS was also significantly associated with two additional temporal parameters - positively with swing time and negatively with double support time variability.

SIGNIFICANCE

The data from this study contributes to reference values database for the use of fast gait assessments in adults.

Five-Year Lower Extremity Function is Associated with White Matter Abnormality in Older Adults

OBJECTIVE

To explore associations between changes of lower extremity function (LEF) parameters over a 5-year period and diffusion tensor imaging (DTI) parameters of white matter tracts among community-dwelling older adults.

DESIGN

A secondary analysis on image and physical function data collected from the Multidomain Alzheimer's Preventive Trial (MAPT).

PARTICIPANTS

208 older adults (aged 75 ± 4 years, with spontaneous memory complaint or limited instrumental daily living activity or slow gait speed, 60% female) of the MAPT-magnetic resonance imaging (MRI) ancillary study. The time interval between a participant's enrolment and MRI scan was on average 110 ± 97 days.

MEASUREMENTS

Forty-eight white matter tracts (WMTs) were measured. LEF parameters (measured after the MRI scan) were assessed as the short physical performance battery (SPPB) score, gait speed, and chair stands time over a 5-year period. Mixed-effects models were performed to explore the associations between baseline DTI values and the progression of LEF parameters. Bonferroni correction was applied for multiple comparison correction.

RESULTS

The progression of LEF was associated with 35 baseline DTI parameters from 24 WMTs. Higher baseline DTI parameter values were related to more decreases in SPPB score and gait speed, and greater increases in chair stands time. Bilateral uncinate fasciculus was associated with all LEF parameters. Other WMTs in cingulum, cerebral and cerebellar peduncle, internal capsule, and corpus callosum also showed close connections with LEF changes.

CONCLUSIONS

Our findings show that DTI parameters of some WMTs are associated with the 5-year decline in LEF, suggesting that alterations in WMT integrity (evaluated by DTI parameters) might be used to explore potential causes of impaired mobility in older adults when no clear explanations can be found.

Comparison of field- and laboratory-based estimates of muscle quality index between octogenarians and young older adults: an observational study

Muscle quality (the ratio of strength to lean muscle mass) might be a better indicator of muscle function than strength alone. Differences in muscle quality index (MQI) between octogenarians and young older adults remain unclear. The aims of the present cross-sectional study were to compare (1) MQI between octogenarians and young older adults, (2) lab versus field-based MQI tools, and (3) determine possible confounding factors affecting MQI in older adults. Compiled data from two cross-sectional studies included 175 younger and older adults (31 men and 144 women) with a mean age of 75.93±9.49 years. Participants with age ≥80 years old were defined as octogenarians (n=79) and <80 years was defined as young older adults (n=96). Laboratory MQI was derived from the ratio of grip strength to arm muscle mass (in kg) measured by dual-energy x-ray absorptiometry. Field-based MQI was quantified from the ratio of grip strength to body mass index (BMI). Octogenarians displayed lower field (P=0.003) and laboratory MQI (P<0.001) as compared with young older adults. There was a strong correlation effect between field MQI and laboratory MQI (P=0.001, R=0.85). BMI (P=0.001), and diabetes mellitus (P=0.001) negatively affected MQI. Women presented lower MQI (P=0.001) values than men. In light of this information, rehabilitation specialists should consider the use of field-based MQI as a tool for evaluation and follow-up of older population.

High density muscle size and muscle power are associated with both gait and sit-to-stand kinematic parameters in frail nonagenarians

Frailty is an important concept in clinical and demographic research in the elderly because of its incidence level and its relationship with adverse outcomes. Functional ability declines with advanced age, likely due to changes in muscle function. This study aimed to examine the relationship between muscle quality and muscle power with kinematics from functional tests in a population of 21 institutionalized frail nonagenarian (91.3 ± 3.1 years). Here, muscle quality was measured by segmenting areas of high- and low-density fibers with computerized tomography. In addition, muscle strength and muscle power were obtained through maximal strength and power tests using resistance exercises. Finally, functional capacity outcomes (i.e., balance, gait velocity and sit-to-stand ability), as well as kinematic parameters, were evaluated from a tri-axial sensor used during a battery of functional tests. Our results show that lower limb muscle quality, maximal strength and power output present statistically significant relationships with different kinematic parameters, especially during the sit-to-stand and gait tests (e.g. leg power and maximum power during sit-to-stand (r = 0.80) as well as quadriceps muscle mass and step asymmetry (r = -0,71). In particular, frail individuals with greater muscle quality needed less trunk range of motion to make the transition between sitting and standing, took less time to stand up, and exerted a major peak power of force. As a conclusion, a loss of muscle quality and power may lead to motor control impairments such as gait, sit-to-stand and balance that can be the cause of adverse events such as falls.

Absolute reliability of tongue pressure measurement in young healthy adults and elderly patients with certification of needing long-term care or support

AIM

We aimed to determine systematic bias and the range of random error in tongue pressure measurements among young healthy adults and elderly patients with certification of requiring long-term care or support, considering sex, and to establish a measurement method.

METHODS

Subjects were 226 adults (88 young healthy adults and 138 elderly patients with certification of requiring long-term care or support). Tongue pressure was measured thrice. Bland-Altman analysis was performed for the first and second trials, and second and third trials.

RESULTS

Fixed bias was revealed for the first and second trials among young healthy adults. Systematic bias was not found for the second and third trials. Fixed bias was revealed for the first and second trials among elderly patients, with a proportional bias with a negative slope for the second and third trials. For young healthy adults, the minimal detectable change was 6.0 and 5.4 kPa in males and females, respectively. For elderly patients, the limit of agreement ranged from -5.9 to 8.6 and from -5.4 to 8.8 kPa in males and females, respectively.

CONCLUSIONS

There was a difference in systematic bias in tongue pressure measurement between young healthy adults and elderly patients with certification of needing long-term care or support. In young healthy adults, the third trial results showed stability, whereas they decreased in elderly patients. In elderly patients, it was suggested that the number of measurements reduced from three to two when a maximum value was adopted. No differences were observed among sexes in either young or elderly patients. Geriatr Gerontol Int 2020; 20: 488-493.

Muscle mass, strength, and physical performance predicting activities of daily living: a meta-analysis

Background Activities of daily living (ADLs) and instrumental activities of daily living (IADLs) are essential for independent living and are predictors of morbidity and mortality in older populations. Older adults who are dependent in ADLs and IADLs are also more likely to have poor muscle measures defined as low muscle mass, muscle strength, and physical performance, which further limit their ability to perform activities. The aim of this systematic review and meta-analysis was to determine if muscle measures are predictive of ADL and IADL in older populations. Methods A systematic search was conducted using four databases (MEDLINE, EMBASE, Cochrane, and CINAHL) from date of inception to 7 June 2018. Longitudinal cohorts were included that reported baseline muscle measures defined by muscle mass, muscle strength, and physical performance in conjunction with prospective ADL or IADL in participants aged 65 years and older at follow-up. Meta-analyses were conducted using a random effect model. Results Of the 7760 articles screened, 83 articles were included for the systematic review and involved a total of 108 428 (54.8% female) participants with a follow-up duration ranging from 11 days to 25 years. Low muscle mass was positively associated with ADL dependency in 5/9 articles and 5/5 for IADL dependency. Low muscle strength was associated with ADL dependency in 22/34 articles and IADL dependency in 8/9 articles. Low physical performance was associated with ADL dependency in 37/49 articles and with IADL dependency in 9/11 articles. Forty-five articles were pooled into the meta-analyses, 36 reported ADL, 11 reported IADL, and 2 reported ADL and IADL as a composite outcome. Low muscle mass was associated with worsening ADL (pooled odds ratio (95% confidence interval) 3.19 (1.29-7.92)) and worsening IADL (1.28 (1.02-1.61)). Low handgrip strength was associated with both worsening ADL and IADL (1.51 (1.34-1.70); 1.59 (1.04-2.31) respectively). Low scores on the short physical performance battery and gait speed were associated with worsening ADL (3.49 (2.47-4.92); 2.33 (1.58-3.44) respectively) and IADL (3.09 (1.06-8.98); 1.93 (1.69-2.21) respectively). Low one leg balance (2.74 (1.31-5.72)), timed up and go (3.41 (1.86-6.28)), and chair stand test time (1.90 (1.63-2.21)) were associated with worsening ADL. Conclusions Muscle measures at baseline are predictors of future ADL and IADL dependence in the older adult population.

Validity, reliability, and feasibility of the uSense activity monitor to register physical activity and gait performance in habitual settings of geriatric patients

OBJECTIVE

The aim of the study was to investigate the psychometric quality of a newly developed activity monitor (uSense) to document established physical activity parameters as well as innovative qualitative and quantitative gait characteristics in geriatric patients.

APPROACH

Construct and concurrent validity, test-retest reliability, and feasibility of established as well as innovative characteristics for qualitative gait analysis were analyzed in multi-morbid, geriatric patients with cognitive impairment (CI) (n  =  110), recently discharged from geriatric rehabilitation.

MAIN RESULTS

Spearman correlations of established and innovative uSense parameters reflecting active behavior with clinically relevant construct parameters were on average moderate to high for motor performance and life-space and low to moderate for other parameters, while correlations with uSense parameters reflecting inactive behavior were predominantly low. Concurrent validity of established physical activity parameters showed consistently high correlations between the uSense and an established comparator system (PAMSys^™), but the absolute agreement between both sensor systems was low. On average excellent test-retest reliability for all uSense parameters and good feasibility could be documented.

SIGNIFICANCE

The uSense monitor allows the assessment of established and-for the first time-a semi-qualitative gait assessment of habitual activity behavior in older persons most affected by motor and CI and activity restrictions. On average moderate to good construct validity, high test-retest reliability, and good feasibility indicated a sound psychometric quality of most measures, while the results of concurrent validity as measured by a comparable system indicated high correlation but low absolute agreement based on different algorithms used.

Fourier-Based Footfall Placement Variability in Parkinson's Disease

The current investigation examined whether Parkinson's patients (PD) have greater Fourier-based footfall placement gait with the greatest mobility dysfunction variability (FPV) than the age and gender matched control group and that variability would be the greatest in the PD participants with the greatest mobility dysfunction indexed Hoehn/Yahr scale. 35 persons undergoing PD and 30 age-matched controls participated in this investigation. Participants repeated two trials' normal walking and average and variability parameters of gait were measured using a 3.66 m electronic walkway. FPV was quantified as a change in the center of pressure during gait. Persons with PD were divided into two groups based on Hoehn/Yahr scale. Overall, persons with PD had smaller average performance indexed by mean and greater gait variability than controls as indexed by CV and Fourier-based variability (p's<0.05). Moreover, PD with higher mobility dysfunction had not only greater variability in traditional parameters but also greater Fourier-based variability than nonfallers with MS (p<.001) with higher effect size (η²=0.37 vs.0.18-0.29). These observations highlight the fact that footfall placement variability is related to mobility dysfunction in PD. Further study is necessary to determine contributing factors to an increased FPV and whether targeted interventions such as exercise can reduce FPV.

Effects of Pulmonary Rehabilitation on Gait Characteristics in Patients with COPD

Pulmonary rehabilitation (PR) improves lower-limb muscle function in patients with chronic obstructive pulmonary disease (COPD). However, it remains unclear whether patients improve gait characteristics, in particular stride-to-stride fluctuations that are associated with fall risks. This study aims to identify whether, and to what extent, PR affects positively gait characteristics in COPD. In this prospective observational study, 44 COPD patients (aged: 62 ± 7 years; Forced expiratory volume in 1 s 56 ± 20% predicted) performed self-paced, treadmill 6-min-walk tests (Gait Real-time Analysis Interactive Lab) before and after PR, while spatiotemporal parameters and center of mass position were recorded (100 Hz, Vicon Nexus). Standard deviation, coefficient of variation, predictability (sample entropy), and consistency in organization (local divergence exponent) were calculated. Sub-analysis was performed to identify gait differences between good and poor responders (<30 m change in a 6-min-walk distance). Patients demonstrated shorter stride times (p = 0.001) and improved lower-limb muscle function (p < 0.001) following PR. The good responders had a greater increase in stride length (p < 0.001) and a greater decrease in stride time (p < 0.001) compared to the poor responders. Current PR improved stride time in patients, while movement patterns within stride-to-stride fluctuations did not change. Training programs specifically targeting balance issues and gait function may be beneficial in improving gait characteristics in COPD.

Explanators of Sarcopenia in Individuals With Diabesity: A Cross-Sectional Analysis

BACKGROUND AND PURPOSE

Excess lower extremity intermuscular adipose tissue (IMAT), reduced strength, and functional limitations are common in obese individuals with and without diabetes (the former termed diabesity). Individuals with diabesity are particularly susceptible to accelerated sarcopenia, which may be underdiagnosed. The purpose of this study was to determine critical values for leg IMAT volume, plantar flexor (PF) muscle strength, and physical performance that help identify individuals with diabesity who have sarcopenia.

METHODS

Forty-three age- and sex-matched obese adults were studied: 12 with type 2 diabetes, 21 with diabetes and peripheral neuropathy, and 10 nondiabetic controls. Dual-energy x-ray absorptiometry-derived skeletal muscle index determined classification of sarcopenia. Leg fat (% IMAT), ankle (PF) peak torque, and power while ascending 10 steps, were used as explanators of sarcopenia. Receiver operating curves identified critical values for each explanator individually. Logistic regression models using all 3 explanators, and only PF torque and stair power, were also created. Receiver operating curve analyses identified the predicted probability that maximized each model's sensitivity and specificity. A leave-one-out cross validation was used to simulate the models' performance in an independent sample.

RESULTS AND DISCUSSION

Thirty-two participants were sarcopenic, and 11 were not. Critical values for individual explanators were 21% IMAT, 68 Nm PF torque, and 441 watts of stair power. Predicted probabilities of .76 and .67 were chosen as the optimal cutoff probabilities for the model combining all 3 explanators, and the model combining PF torque and stair power, respectively. The cross-validation analysis produced an accuracy of 82.4%, using the cutoff probability of .5, and an accuracy of 76.5% using the cutoff of 0.76. The area under the curve for the cross validation receiver operating curve analysis was 0.82. Critical values of leg % IMAT, PF torque, and stair power can classify individuals with diabesity as sarcopenic. The results of the cross validation give us confidence that the sample used in this study was representative of the target population, and suggests models created from this sample may perform well in externally derived data sets.

CONCLUSION

Clinicians may be able to use these critical values to select interventions that specifically target sarcopenia. Measures of % IMAT, PF torque, and stair power may offer a customized alternative to traditional sarcopenic classification systems, which may not be optimally suited to the common impairments among individuals with diabesity.

Patients with Chronic Obstructive Pulmonary Disease Walk with Altered Step Time and Step Width Variability as Compared with Healthy Control Subjects

RATIONALE

Compared with control subjects, patients with chronic obstructive pulmonary disease (COPD) have an increased incidence of falls and demonstrate balance deficits and alterations in mediolateral trunk acceleration while walking. Measures of gait variability have been implicated as indicators of fall risk, fear of falling, and future falls.

OBJECTIVES

To investigate whether alterations in gait variability are found in patients with COPD as compared with healthy control subjects.

METHODS

Twenty patients with COPD (16 males; mean age, 63.6 ± 9.7 yr; FEV₁/FVC, 0.52 ± 0.12) and 20 control subjects (9 males; mean age, 62.5 ± 8.2 yr) walked for 3 minutes on a treadmill while their gait was recorded. The amount (SD and coefficient of variation) and structure of variability (sample entropy, a measure of regularity) were quantified for step length, time, and width at three walking speeds (self-selected and ±20% of self-selected speed). Generalized linear mixed models were used to compare dependent variables.

RESULTS

Patients with COPD demonstrated increased mean and SD step time across all speed conditions as compared with control subjects. They also walked with a narrower step width that increased with increasing speed, whereas the healthy control subjects walked with a wider step width that decreased as speed increased. Further, patients with COPD demonstrated less variability in step width, with decreased SD, compared with control subjects at all three speed conditions. No differences in regularity of gait patterns were found between groups.

CONCLUSIONS

Patients with COPD walk with increased duration of time between steps, and this timing is more variable than that of control subjects. They also walk with a narrower step width in which the variability of the step widths from step to step is decreased. Changes in these parameters have been related to increased risk of falling in aging research. This provides a mechanism that could explain the increased prevalence of falls in patients with COPD.

Development of a rapid stepping test to challenge rapid weight-shifting function in older adults

BACKGROUND

The ability to step rapidly, shift weight from side-to-side, and maintain temporal rhythmicity are important functional elements for walking independently and preventing falls in seniors.

AIMS

The purpose of this study was to develop a clinically feasible test of rapid stepping performance that challenges the ability to step rapidly, shift weight from side-to-side, and maintain temporal rhythmicity.

METHODS

Participants were a volunteer sample of healthy, self-ambulating older adults aged 70-98 years. A Repeated Alternating Stair Touch Test was developed, which involved rapidly shifting weight in the medial-lateral direction by tapping each foot alternately onto a step. Performance on the test was assessed using trunk acceleration signals. Associations between the number of steps completed on the Repeated Alternating Stair Touch Test in 20 s and acceleration magnitude, variability, and stepping rhythmicity were assessed using Pearson correlations and linear regression. Repeatability was assessed during a 2-week follow-up period.

RESULTS

The acceleration magnitude, variability, and stepping rhythmicity variables related moderately with the number of steps on the Repeated Alternating Stair Touch Test (r = 0.534-0.572, p < 0.05) and were independent predictors of the number of steps taken (R ² adj. = 0.624, p < 0.001). Repeatability was mixed, though most acceleration variables and number of steps had moderate to high correlations between sessions (intraclass correlations: 0.486-0.828), but a learning effect was evident; performance improved between sessions.

CONCLUSION

The Repeated Alternating Stair Touch Test has potential as a simple test of rapid, rhythmic weight-shifting function, but requires modification to improve repeatability.

[Subjective Gait Stability in the Elderly]

BACKGROUND

It can be assumed that the feeling of gait stability or gait instability in the elderly may be independent of a possible fear of falling or a history of falling when walking. Up to now, there has been a lack of spatiotemporal gait parameters for older people who subjectively feel secure when walking.

OBJECTIVE

The aim of the study is to analyse the distribution of various gait parameters for older people who subjectively feel secure when walking.

MATERIALS AND METHODS

In a cross-sectional study, the gait parameters stride time, step time, stride length, step length, double support, single support, and walking speed were measured using a Vicon three-dimensional motion capture system (Plug-In Gait Lower-Body Marker Set) in 31 healthy people aged 65 years and older (mean age 72 ± 3.54 years) who subjectively feel secure when walking.

RESULTS

There was a homogeneous distribution in the gait parameters examined, with no abnormalities. The mean values have a low variance with narrow confidence intervals.

CONCLUSION

This study provides evidence that people who subjectively feel secure when walking demonstrate similarly objective gait parameters..

Generating linear regression model to predict motor functions by use of laser range finder during TUG

PURPOSE

The purpose of this study was to investigate which spatial and temporal parameters of the Timed Up and Go (TUG) test are associated with motor function in elderly individuals.

METHODS

This study included 99 community-dwelling women aged 72.9 ± 6.3 years. Step length, step width, single support time, variability of the aforementioned parameters, gait velocity, cadence, reaction time from starting signal to first step, and minimum distance between the foot and a marker placed to 3 in front of the chair were measured using our analysis system. The 10-m walk test, five times sit-to-stand (FTSTS) test, and one-leg standing (OLS) test were used to assess motor function. Stepwise multivariate linear regression analysis was used to determine which TUG test parameters were associated with each motor function test. Finally, we calculated a predictive model for each motor function test using each regression coefficient.

RESULTS

In stepwise linear regression analysis, step length and cadence were significantly associated with the 10-m walk test, FTSTS and OLS test. Reaction time was associated with the FTSTS test, and step width was associated with the OLS test. Each predictive model showed a strong correlation with the 10-m walk test and OLS test (P < 0.01), which was not significant higher correlation than TUG test time.

CONCLUSION

We showed which TUG test parameters were associated with each motor function test. Moreover, the TUG test time regarded as the lower extremity function and mobility has strong predictive ability in each motor function test.

The degree of misjudgment between perceived and actual gait ability in older adults

Successful execution of motor tasks requires an integration of the perception of one's physical abilities and the perception of the task itself. Physical and cognitive decline associated with ageing may lead to misjudgments of these perceived and actual abilities and possibly to errors that may lead to balance loss. We aimed to directly quantify the degree to which older adults misjudge their actual gait ability. Twenty-seven older adults participated and were instructed to walk on a narrow path projected on a treadmill. We tested two paradigms to estimate the participants' perceived gait ability: a path width manipulation, in which participants had to indicate the smallest path width that they could walk on without stepping outside or losing balance (at given speed), and a treadmill speed manipulation, in which they had to indicate the maximum speed that they could use at a given path width. We determined their actual ability as the probability of stepping inside the path over a range of path widths and speeds. The path width paradigm seemed suitable for evaluating self-perception of actual gait ability and revealed that participants appeared to show a range of misjudgment towards either over- or underestimating their actual abilities. Better abilities appeared not associated with better judgment. Direct quantification of the degree of misjudgment provides insight in the interplay between cognition and physical abilities and can be of added value towards prevention of falls and promotion of healthy ageing.

Cognitive Motor Interference in Multiple Sclerosis: Insights From a Systematic Quantitative Review

OBJECTIVE

To synthesize the evidence for differences in cognitive motor interference (CMI) between persons with multiple sclerosis (MS) and those without MS by using systematic review and meta-analysis.

DATA SOURCES

EMBASE, PubMed, ScienceDirect, Scopus, SPORTDiscus, and Web of Science. Our focused literature search was informed by past systematic reviews of CMI during walking in MS.

STUDY SELECTION

The key terms searched included Multiple sclerosis and synonyms of motor function (eg, Gait disorders, Gait, Walking, Balance, or Fall) and motor and cognitive functions (eg, Cognitive motor interference or Thinking).

DATA EXTRACTION

From the 116 abstract-identified articles, 13 experimental studies were selected for the final analysis and were rated using the Quality Assessment of Diagnostic Accuracy Studies tool. A meta-analysis was performed for all considered outcomes.

DATA SYNTHESIS

The results yielded a small overall effect size (ES) of .08 (SE=.17; 95% confidence interval, -.25 to .40; z=.49; P>.05), which indicated a nonsignificant minimal difference in CMI between persons with MS and those without MS. The moderator analysis for motor task (mobility task: ES, .22; postural task: ES, -.11) was not significantly different between persons with MS and those without MS. The moderator analysis for cognitive task (verbal fluency task: ES, .66; mental tracking task: ES, .04; discrimination and decision-making task: ES, -.30) resulted in a significant difference in CMI between persons with MS and those without MS (P<.05).

CONCLUSIONS

We provide evidence that overall there is a minimal difference in CMI between persons with MS and those without MS.

Associations Between Measures of Balance and Lower-Extremity Muscle Strength/Power in Healthy Individuals Across the Lifespan: A Systematic Review and Meta-Analysis

BACKGROUND

It has frequently been reported that balance and lower-extremity muscle strength/power are associated with sports-related and everyday activities. Knowledge about the relationship between balance, strength, and power are important for the identification of at-risk individuals because deficits in these neuromuscular components are associated with an increased risk of sustaining injuries and falls. In addition, this knowledge is of high relevance for the development of specifically tailored health and skill-related exercise programs.

OBJECTIVES

The objectives of this systematic literature review and meta-analysis were to characterize and, if possible, quantify associations between variables of balance and lower-extremity muscle strength/power in healthy individuals across the lifespan.

DATA SOURCES

A computerized systematic literature search was performed in the electronic databases PubMed, Web of Science, and SPORTDiscus up to March 2015 to capture all relevant articles.

STUDY ELIGIBILITY CRITERIA

A systematic approach was used to evaluate the 996 articles identified for initial review. Studies were included only if they investigated healthy individuals aged ≥6 years and tested at least one measure of static steady-state balance (e.g., center of pressure [CoP] displacement during one-legged stance), dynamic steady-state balance (e.g., gait speed), proactive balance (e.g., distance in the functional-reach-test), or reactive balance (e.g., CoP displacement during perturbed one-legged stance), and one measure of maximal strength (e.g., maximum voluntary contraction), explosive force (e.g., rate of force development), or muscle power (e.g., jump height). In total, 37 studies met the inclusionary criteria for review.

STUDY APPRAISAL AND SYNTHESIS METHODS

The included studies were coded for the following criteria: age (i.e., children: 6-12 years, adolescents: 13-18 years, young adults: 19-44 years, middle-aged adults: 45-64 years, old adults: ≥65 years), sex (i.e., female, male), and test modality/outcome (i.e., test for the assessment of balance, strength, and power). Studies with athletes, patients, and/or people with diseases were excluded. Pearson's correlation coefficients were extracted, transformed (i.e., Fisher's z-transformed r z value), aggregated (i.e., weighted mean r z value), back-transformed to r values, classified according to their magnitude (i.e., small: r ≤ 0.69, medium: r ≤ 0.89, large: r ≥ 0.90), and, if possible, statistically compared. Heterogeneity between studies was assessed using I2 and Chi-squared (χ2) statistics.

RESULTS

Three studies examined associations between balance and lower-extremity muscle strength/power in children, one study in adolescents, nine studies in young adults, three studies in middle-aged adults, and 23 studies in old adults. Overall, small-sized associations were found between variables of balance and lower-extremity muscle strength/power, irrespective of the age group considered. In addition, small-sized but significantly larger correlation coefficients were found between measures of dynamic steady-state balance and maximal strength in children (r = 0.57) compared with young (r = 0.09, z = 3.30, p = 0.001) and old adults (r = 0.35, z = 2.94, p = 0.002) as well as in old compared with young adults (z = 1.95, p = 0.03).

LIMITATIONS

Even though the reported results provided further insight into the associations between measures of balance and lower-extremity muscle strength/power, they did not allow us to deduce cause and effect relations. Further, the investigated associations could be biased by other variables such as joint flexibility, muscle mass, and/or auditory/visual acuity.

CONCLUSIONS

Our systematic review and meta-analysis showed predominately small-sized correlations between measures of balance and lower-extremity muscle strength/power in children, adolescents, and young, middle-aged, and old adults. This indicates that these neuromuscular components are independent of each other and should therefore be tested and trained complementarily across the lifespan. Significantly larger but still small-sized associations were found between measures of dynamic steady-state balance and maximal strength in children compared with young and old adults as well as in old compared with young adults. These findings imply that age/maturation may have an impact on the association of selected components of balance and lower-extremity muscle strength.

An exploratory investigation of changes in gait parameters with age in elderly Japanese women

BACKGROUND

The aim of the present study was to identify gait parameters in elderly Japanese women. 30 elderly women (65-74.9 years old) and 19 very elderly women (≥75 years old) participated in this study. A 3-dimensional (3D) motion analysis system was used to collect kinematic data, and a total of 70 gait parameters were analysed. Gait parameters included basic gait parameters, gait cycle parameters, and joints angle parameters, as well as angular velocity parameters, such as peak velocity and timing at the hip, knee, and ankle joints.

RESULTS

Our results indicated that basic gait parameters, such as the gait cycle, peak joint angle timing, and angular velocity parameters, significantly differ between elderly and very elderly women. Delayed peak joint angle timing and angular velocity parameters occurred during critical phases throughout the gait cycle: pre-swing, initial swing, and terminal swing phases.

CONCLUSIONS

Several gait parameters exhibited significant differences between elderly and very elderly women. The timing of the peak joint angle and angular velocity parameters are primary characteristics defining gait changes in the elderly.

Anti-sarcopenic effects of diamino-diphenyl sulfone observed in elderly female leprosy survivors: a cross-sectional study

BACKGROUND

It has been reported that 4,4'-diamino-diphenyl sulfone (DDS), the longtime treatment of choice for leprosy, prolongs the lifespan and increases mobility in animal models by reducing the levels of reactive oxygen species and inhibiting muscle pyruvate kinase activity. This study aimed to investigate whether sarcopenic status in leprosy survivors was influenced by recent history of DDS medication.

METHODS

Forty-one elderly female leprosy survivors were recruited. The DDS group was defined as survivors who had been taking the drug for the past year or more. Body composition measured by dual energy X-ray absorptiometry, limb muscle strength, short physical performance battery, and International Physical Activity Questionnaire in Korean were compared.

RESULTS

The DDS group tended to have higher skeletal muscle mass index (24.4 ± 2.7 vs. 22.6 ± 2.2%, P = 0.066) and regional skeletal muscle mass index in non-dominant leg (8.9 ± 1.0 vs. 7.9 ± 0.9%, P = 0.018) than those of the control group although they had significantly worse leprosy disability than the control group (P = 0.027). The DDS group had greater strength than the control group in non-dominant shoulder abductor, elbow flexor, hip flexor, and knee extensor (P = 0.005, P = 0.029, P = 0.021, and P = 0.002, respectively). Weekly walking amount was significantly longer (P = 0.020) in the DDS group than the control group. The total lifetime DDS exposure significantly correlated with skeletal muscle mass of the lower extremity in non-dominant leg (r = 0.379, P = 0.015).

CONCLUSIONS

DDS-taking leprosy survivors had larger skeletal muscle mass and greater muscle strength over non-taking survivors. There was a dose-response relationship between total lifetime DDS exposure and skeletal muscle mass of lower extremity. These findings might suggest potential anti-sarcopenic effects of DDS.

Differences in Functional Fitness Among Older Adults With and Without Risk of Falling

PURPOSE

This study aimed to identify the differences in functional fitness between older adults who were at risk of falling and those who were not.

METHODS

A total of 104 older adults aged 65-74 years were recruited from a local community senior center. They were independent older adults without a history of falls in the preceding 12 months. Falling risk status was assessed using the Fall Risk Test. Five dimensions of functional fitness with seven testing parameters (i.e., 30-second chair stand test, 30-second arm curl test, 2-minute step test, chair sit and reach test, back scratch test, 8-foot up and go test, and body mass index) were evaluated by the Senior Fitness Test.

RESULTS

Only 78 participants completed all the tests, of which 48 participants were identified with risk of falling, and 30 participants were free from risk of falling. Results from multivariate analysis of variance found significant differences on the combined outcome variables, especially in the 8-foot up and go test, 2-minute step test, and 30-second arm curl test. Results from discriminant analysis found a significant discriminant function among all the seven testing parameters, where the 8-foot up and go test, and the 2-minute step test contributed most.

CONCLUSIONS

Older adults who are at the early stage of risk of falling tend to have lower functional fitness capacities, especially in agility and dynamic balance, aerobic endurance as well as in a combined relationship among all the testing parameters.

A Pilot Study of Gait Function in Farmworkers in Eastern North Carolina

Farmworkers endure many job-related hazards, including fall-related work injuries. Gait analysis may be useful in identifying potential fallers. The goal of this pilot study was to explore differences in gait between farmworkers and non-farmworkers. The sample included 16 farmworkers and 24 non-farmworkers. Gait variables were collected using the portable GAITRite system, a 16-foot computerized walkway. Generalized linear regression models were used to examine group differences. All models were adjusted for two established confounders, age and body mass index. There were no significant differences in stride length, step length, double support time, and base of support; but farmworkers had greater irregularity of stride length (P = .01) and step length (P = .08). Farmworkers performed significantly worse on gait velocity (P = .003) and cadence (P < .001) relative to non-farmworkers. We found differences in gait function between farmworkers and non-farmworkers. These findings suggest that measuring gait with a portable walkway system is feasible and informative in farmworkers and may possibly be of use in assessing fall risk.

Parameters of gait among community-dwelling older adults

BACKGROUND

Functional fitness is the ability of an older adult to perform activities of daily living. Stair-climb power is a well-documented marker of functional fitness among older adults. Gait velocity and parameters of gait are related to functional fitness but have been understudied to date.

PURPOSE

The purpose of this observational study was to determine differences in parameters of gait between high- and low-functioning older adults.

METHODS

Twenty high-functioning older adults, mean age (SD)=71.6 (5.6), volunteered for the cross-sectional observational study. Functional fitness was determined by a stair-climb performance test. Parameters of gait included velocity, step length, swing and stance phase, double support time, ground reaction forces, impulse, and propulsion during habitual walking. Analysis of variance was performed to determine differences in the dependent variables between groups.

RESULTS

Individuals with high levels of functional fitness walked 13.1% faster than the lower-functioning group (P=.01). No significant differences (P>.05) were detected for any other measure; however, all gait parameters were more favorable in the higher-functioning group.

CONCLUSION

Functional fitness is imperative for older adults as declines could hinder mobility. Thus, earlier detection of declines in gait parameters may reduce the risk of falling. The results suggest that gait velocity was slower among older adults with lower levels of functional fitness.

Examination of spatiotemporal gait parameters during the 6-min walk in individuals with multiple sclerosis

This investigation examined spatiotemporal parameters of gait during the 6-min walk (6MW) in individuals with multiple sclerosis (MS) and in healthy controls. Eighteen individuals with MS [divided into those who were independently ambulatory (n=10) and those who were ambulatory with assistance (n=8)] and 10 healthy controls performed a 6MW while recording spatiotemporal gait parameters using a pressure-sensitive walkway. Parameters recorded were walking velocity, cadence, step length and width, step time, percent of the gait cycle in double support, and variability of step length and width, step time, and double support. The ambulatory with assistance MS group had a significantly greater reduction in walking velocity (P=0.000) over the course of the 6MW, which coincided with a significantly greater increase in step time and double support (P=0.029) than in the other groups. Only the ambulatory with assistance MS group showed an increase in step-time variability and double-support variability during the 6MW (P's<0.05). The novel results indicate that the reduction in velocity over prolonged walking occurs through a greater change in the temporal parameters of gait in persons with MS who require assistance while walking. In addition, the increase in gait variability in the individuals with MS who require assistance while walking indicates that the control over walking further deteriorates over the course of the 6MW.

Hip but not thigh intramuscular adipose tissue is associated with poor balance and increased temporal gait variability in older adults

BACKGROUND

Intramuscular adipose tissue (IMAT) of the lower extremity is a strong negative predictor of mobility function. Variability in temporal gait factors is another important predictor of mobility function. The purpose of this study was to examine the relationships between IMAT in the hip and thigh muscles, balance, and temporal gait variability in older adults.

METHODS

Forty-eight healthy community dwelling older adults (74 +/- 1 year) underwent a CT scan to quantify IMAT in the gluteus maximus (Gmax), gluteus medius/minimus (Gmed/min), hamstrings, vastus lateralis, and adductor muscles. Temporal Gait measures were collected on a GAITRite walkway and gait variability was determined by calculating intraindividual standard deviations. Individuals were divided by tertiles of temporal gait variability into categories of high, medium, and low variability. Differences in the IMAT of the hip abductors were calculated for those with high and low gait variability and partial correlations for gait variability and all muscle composition measures were determined for all variables with normalized gait speed as a covariate.

RESULTS

Gmed/min IMAT was greater in those with higher gait variability compared to those with lower gait variability (p<0.05). Gmed/min IMAT was related to stride width variability (r=0.30, p<0.05). Gmax IMAT was also related to time variability of swing (r=0.42), stance (r=0.26), double limb support (r=0.43), double support loading (r=0.44), and double support unloading (r=0.50) (all p<0.05).

CONCLUSION

Increased IMAT in the proximal hip muscles, particularly the hip abductors, was associated with increased gait variability and poorer balance. These findings may have implications for the assessment and treatment of balance and falls such that interventions for enhancing balance and mobility among older individuals should take into account the importance of gluteal muscle composition.

Associations between measures of gait stability, leg strength and fear of falling

Fear of falling (FoF) in elderly frequently leads to decreased quality of life. FoF is suggested to be associated with changes in gait quality and muscle strength with aging. The aim of this study was to determine whether gait quality and maximal voluntary torque (MVT) of knee extensor muscles are associated with FoF. We hypothesized that high between-stride variability and local divergence exponent (LDE) of trunk kinematics in gait are associated with higher FoF in non-fallers, but not in fallers. Moreover, we hypothesized that knee extensor muscle strength is associated with a high variability and LDE of trunk kinematics during gait. 134 four adults, aged 62.4 (SD 6.2) years agreed to participate. FoF was assessed on a 10-point numerical rating scale. Subjects with at least one fall in the past 12 months were considered as fallers. LDE and variability were calculated from data of a trunk-mounted inertial-sensor collected during several minutes of treadmill walking. Maximal voluntary knee extension torque (MVT) was assessed isometrically. Fall history was an effect modifier in the association between LDE and FoF only, i.e. only subjects without fall history and a high LDE had a five times higher chance of reporting FoF. Gait variability was not associated with FoF. Low MVT was associated with FoF. Multivariate analysis demonstrated that LDE was more strongly associated with FoF than MVT. Decreased stability of gait as reflected in a high LDE and low muscle strength are associated with and a potential cause of FoF in subjects without fall history.