Effect of body mass index and fat mass on balance force platform measurements during a one-legged stance in older adults

Association between the fat mass/fat-free mass ratio and muscle strength, static balance and exercise capacity in older adults: a cross-sectional study

BACKGROUND

the FM/FFM ratio has been proposed as a new body composition variable. However, the association between FM/FFM ratio and physical function in older adults remains limited. Therefore, the aim of this study was to analyze the association between FM/FFM ratio and muscle strength, static balance, and exercise capacity in older adults.

METHODS

this was a cross-sectional study involving 392 older adults from Londrina, Brazil. Subjects underwent body composition analysis by bioelectrical impedance, and assessments for aerobic capacity, muscle strength and static balance including the 6-minutes walking test, handgrip strength and one-legged stance test. Statistical analysis was conducted using correlation tests and lineal regression models adjusted for age and gender. The statistical significance considered was p < 0.05.

RESULTS

a total of 392 older adults participated (mean age = 69.77 years; women: 74.7 %). The FM/FFM ratio was significantly associated with muscle strength (β = -22.779, 95 % CI: -26.741 to -18.818; p < 0.001), static balance (β = -14.335, 95 % CI: -19.980 to -8.690; p < 0.001), and exercise capacity (β =-98.937, 95 % CI: -152.286 to -45.588, p < 0.001). After adjusting for age and gender, FM/FFM ratio was an important predictor of muscle strength (β = -4.687, 95 % CI: -8.646 to -0.728; p = 0.020) and static balance (β = -18.361, 95 % CI: -24.943 to -11.778; p < 0.001).

CONCLUSIONS

the FM/FFM ratio is an important clinical measure of body composition that is significantly associated with key indicators of physical performance, including muscle strength, static balance, and exercise capacity in older adults.

Convergent Validity of the Lower Quarter Y Balance Test Against Two-Step and Timed Up and Go Tests in Thai Older Adults with and Without Locomotive Syndrome

Locomotive syndrome (LS) predisposes older adults to falls and functional dependency. In older adults with LS, the validity of the Lower Quarter Y Balance Test (YBT-LQ)-a dynamic balance assessment tool-remains unclear. This cross-sectional study aimed to assess the convergent validity of the YBT-LQ with the Two-Step and Timed Up and Go (TUG) tests and compare YBT-LQ performance between individuals with and without LS. Sixty Thai community-dwelling older adults (≥60 years) were equally divided into LS and non-LS groups and performed the YBT-LQ, Two-Step test, and TUG test. Correlation analyses and independent t-tests assessed relationships and between-group comparisons, respectively. The YBT-LQ exhibited moderate positive correlations with the Two-Step test (r = 0.366, p = 0.004) and moderate negative correlations with the TUG test (r = -0.412, p = 0.001). The LS group exhibited significantly lower YBT-LQ scores across all reach directions than the non-LS group (p < 0.05), highlighting impaired balance in individuals with LS. The YBT-LQ is a valid and reliable tool for assessing dynamic balance and postural control, as well as identifying multidirectional stability deficits in older adults, particularly those with LS. Implementing the YBT-LQ in routine geriatric evaluations could enhance early detection and targeted interventions to reduce fall risk and improve mobility in aging populations.

The Effect of Weight Distribution in the Foot on Balance and Plantar Pressure in Female Adolescent Athletes

BACKGROUND

It is widely reported that the weight distribution in each foot is approximately 60% in the rearfoot and 40% in the forefoot. For balance training, it is recommended to transfer some weight to the forefoot. However, it is still unclear whether fore-rear foot weightbearing ratio affects balance and plantar pressure parameters.

HYPOTHESIS

There is a relationship between the forefoot weightbearing ratio and balance and plantar pressure in female adolescent athletes.

STUDY DESIGN

Cross-sectional study.

LEVEL OF EVIDENCE

Level 3.

METHODS

A total of 91 adolescent female athletes aged between 10 and 19 years were included in the study. Weightbearing ratios of the forefoot, balance, and plantar pressure were assessed using a plantar pressure platform (FootWork, AMCube IST). In the static and stabilometric evaluation, the weightbearing ratio (%), mean and maximum plantar pressure (kPa), center of pressure (CoP) total, antero-posterior and medio-lateral sway length (cm), CoP surface area (cm2), and length over area (cm-1) were recorded. In the dynamic evaluation, the maximum pressure (kPa) acting on each foot was recorded.

RESULTS

Two groups with forefoot weightbearing ratio <40% and ≥40% were compared. Maximum pressure values in static conditions, CoP anteroposterior, and total sway length were significantly different between these groups. In addition, as the amount of load transferred to the forefoot increased, CoP total and anteroposterior sway length increased postural stability.

CONCLUSION

Although postural control mechanisms are quite complex, plantar pressure and postural control parameters can be varied by optimizing rear-to-fore foot weight transfer.

CLINICAL RELEVANCE

This study will contribute to the development of appropriate training and rehabilitation strategies to optimize athlete performance and reduce injury risk.

Comparative analysis of postural stability and risk of falling and developing disability among overweight and obese women over 40 years

BACKGROUND

Increased body mass index (BMI) adversely affects the mechanics of the musculoskeletal system. It is known that obese people have poorer postural stability and mobility-related outcomes compared to normal weight people, but there is limited research comparing overweight and class 1 obese people, two consecutive and prevalent BMI categories.

AIMS

To compare postural stability, functional mobility, and risk of falling and developing disability between overweight and obese women, and to investigate the relationship of BMI and body weight with the outcomes.

METHODS

Thirty women with class 1 obesity and 30 overweight women were included. Standing postural stability with eyes-open and eyes-closed and stability limits were assessed using the Prokin system. The Timed Up and Go Test (TUG) was used to assess functional mobility and risk of falling (≥11 s) and developing disability (≥9 s).

RESULTS

The average center of pressure displacements on the y-axis (COPY) obtained during quiet standing with both eyes-open and eyes-closed were higher in obese women than overweight women (p < 0.05) and the effect sizes were moderate for the results. The COPY values in the eyes-open and eyes-closed conditions were correlated with BMI (r = 0.295 and r = 0.285, p < 0.05). Furthermore, the COPX value in the eyes-open condition and the TUG score were correlated with body weight (r = 0.274 and r = 0.257, p < 0.05).

CONCLUSIONS

Obese women had poorer static standing stability in the anteroposterior direction than overweight women, while functional mobility and risk of falling and developing disability did not differ. Furthermore, BMI and body weight were related to poorer static standing stability.

Impact of frailty and sex-related differences on postural control and gait in older adults with Parkinson's Disease

BACKGROUND

Parkinson's Disease (PD), a neurodegenerative condition, affects normal aging and leads to reduced motor abilities. In addition, frailty syndrome can increase vulnerability and risks of undesirable effects such as disease progression, falls, disability, and premature death among individuals with PD.

AIMS

To assess the impact of frailty on balance and gait parameters in older with PD and to determine if sex mediates these measures.

METHODS

Twenty-seven (27) participants (n = 18 men; n = 10 frail) performed 4 balance tasks on a force platform (eyes opened/closed in bipodal/semi-tandem position) while linear center of pressure (COP) parameters were calculated. Participants also performed two different speed walks on a gait analysis system to assess gait parameters.

RESULTS

Significant differences between the frail and non-frail group were observed on postural control (mainly for area of COP p = 0.013/d = 0.47/70 %; sway velocity p = 0.048/d = 0.41/23 %) where frail reported poor balance. No significant sex differences were reported for postural control. Gait analysis was comparable between frail and non-frail, while significant differences between men and women were observed for step length (p = 0.002, d = 0.71), step width (p = 0.001, d = 0.75) and base of support (p = 0.012, d = 0.64) variables.

CONCLUSION

Frail Parkinson's individuals present poorer postural control than non-frail individuals, but comparable gait parameters. Men and women are comparable on postural control but show different gait parameters. These results may have implications in clinical decision-making in rehabilitation for frailty in older adults, men and women with Parkinson's disease when balance and gait are of concern.

Dual-task performance and balance in patients with severe COPD: a cross-sectional study

BACKGROUND

Chronic obstructive pulmonary disease (COPD) significantly impacts respiratory and motor function, balance, and cognition, leading to muscle weakness and impaired exercise capacity. The impairments often result in challenges with daily activities, particularly those requiring dual-tasking.

OBJECTIVES

The study investigated whether patients with severe COPD would exhibit more significant cognitive and motor performance decline during dual tasks compared to healthy controls.

DESIGN

This study employed a cross-sectional design to compare cognitive and motor performance in dual tasks between patients with severe COPD and healthy controls.

METHODS

We included 44 patients with severe COPD and 43 healthy individuals. Participants underwent various tests, including pulmonary function tests, six-minute walking tests, dual Timed Up and Go tests (TUG), dual single-leg stance tests (SLS), Berg Balance Scale assessments, and Falls Efficacy Scale International evaluations (FES-I).

RESULTS

The COPD group had significantly lower scores in the Berg Balance Scale (BBS; 44.79 ± 4.70 vs 52.67 ± 2.16, p < 0.0001) and longer times for the TUG test (12.44 s; [11.44, 13.50] vs 9.14 s; [7.91, 10.11], p < 0.0001) and shorter times for the SLS test (14.15 s; [12.31, 15.65] vs 26.20 s; [23.45, 30.88], p < 0.0001), indicating poorer functional mobility and balance. Furthermore, dual-task interference (DTI) outcomes revealed poorer performance in the COPD group (p < 0.0001). The fear of falling (FES-I) was increased in the COPD group. There was a significant positive correlation between DTI TUG and FES-I (r = 0.35, p = 0.01) and a negative correlation between DTI SLS and BBS (r = -0.41, p = 0.005) in the COPD group.

CONCLUSION

The study reveals significant impairments in DTI and balance among patients with severe COPD. Patients with severe COPD performed worse in tests involving dual tasks. They had poorer balance overall compared to healthy controls, with longer times for the dual Timed Up and Go test and shorter times for the SLS test, indicating a higher susceptibility to DTI and a greater fear of falling.

The impact of obesity on static and proactive balance and gait patterns in sarcopenic older adults: an analytical cross-sectional investigation

Background

Obesity is increasingly recognized as a significant factor in the susceptibility of older adults to falls and related injuries. While existing literature has established a connection between obesity and reduced postural stability during stationary stances, the direct implications of obesity on walking dynamics, particularly among the older adults with sarcopenia, are not yet comprehensively understood.

Objective

Firstly, to investigate the influence of obesity on steady-state and proactive balance, as well as gait characteristics, among older adults with sarcopenic obesity (SO); and secondly, to unearth correlations between anthropometric characteristics and balance and gait parameters in the same demographic.

Methods

A cohort of 42 participants was categorized into control (CG; n = 22; age = 81.1 ± 4.0 years; BMI = 24.9 ± 0.6 kg/m²) and sarcopenic obese (SOG; n = 20; age = 77.7 ± 2.9 years; BMI = 34.5 ± 3.2 kg/m²) groups based on body mass index (BMI, kg/m²). Participants were assessed for anthropometric data, body mass, fat and lean body mass percentages (%), and BMI. Steady-state balance was gauged using the Romberg Test (ROM). Proactive balance evaluations employed the Functional Reach (FRT) and Timed Up and Go (TUG) tests. The 10-m walking test elucidated spatiotemporal gait metrics, including cadence, speed, stride length, stride time, and specific bilateral spatiotemporal components (stance, swing, 1st and 2nd double support, and single support phases) expressed as percentages of the gait cycle.

Results

The time taken to complete the TUG and ROM tests was significantly shorter in the CG compared to the SOG (p < 0.05). In contrast, the FRT revealed a shorter distance achieved in the SOG compared to the CG (p < 0.05). The CG exhibited a higher gait speed compared to the SOG (p < 0.05), with shorter stride and step lengths observed in the SOG compared to the CG (p < 0.05). Regarding gait cycle phases, the support phase was longer, and the swing phase was shorter in the SOG compared to the CG group (p < 0.05). LBM (%) showed the strongest positive correlation with the ROM (r = 0.77, p < 0.001), gait speed (r = 0.85, p < 0.001), TUG (r = -0.80, p < 0.001) and FRT (r = 0.74, p < 0.001).

Conclusion

Obesity induces added complexities for older adults with sarcopenia, particularly during the regulation of steady-state and proactive balance and gait. The percentage of lean body mass has emerged as a crucial determinant, highlighting a significant impact of reduced muscle mass on the observed alterations in static postural control and gait among older adults with SO.

What Influences Proprioceptive Impairments in Patients with Rheumatic Diseases? Analysis of Different Factors

Rheumatic diseases lead to postural problems, which increase the risk of falls and lead to greater disability. The aim of the present work is to evaluate posture disorders in patients with osteoarthritis (OA) and rheumatoid arthritis (RA), as well as to evaluate the influence of other factors. A total of 71 subjects were enrolled in this study. Joint position sense (JPS) and the functional assessment of proprioception on a balance platform for both lower limbs were examined. The Average Trace Error (ATE), test time (t), and Average Platform Force Variation (AFV) were calculated. Additionally, an equilibrium test was carried out in the one-legged standing position (Single Leg Stance-SLS). The results were compared in several ways and revealed the following: (1) A JPS of 10° plantar flexion in RA obtained significantly worse results when repeating the movement than OA; the ATEs were significantly lower in RA; and RA needed more support during SLS assessment. (2) RA patients with higher DAS28 had statistically significantly higher values in JPS, with 5° plantar flexion and 10° dorsal flexion, SLS assessment, and stabilometric rates. A statistically significant correlation between DAS28 and RA was found in a JPS of 10° plantar flexion. The VAS ruler demonstrated a significant moderate correlation with t. (3) Patients who experienced at least one fall demonstrated higher JPS and t. Our study shows that proprioception is the most influenced by the nature of the disease and the level of disease activity. We can see that the stability and balance functions are also greatly influenced by the patient's falling experience and the level of pain. These findings may be useful in designing an optimal proprioception-enhancing movement training plan.

Impact of plantar fasciitis on postural control and walking in young middle-aged adults

PURPOSE

To assess if plantar fasciitis has an impact on postural control and walking pattern from gait analysis across different experimental conditions.

METHODS

Thirty participants (n = 15 with plantar fasciitis) performed 5 different balance tasks on a force platform, and the center of pressure (COP) was computed for postural control analysis. Participants were also asked to walk at 3 different speeds on a gait analysis system to compute the spatial-temporal parameters. Clinical foot measurements (pain, mobility) were also collected through all participants.

RESULTS

Clinical foot measurements showed no significant difference between the two groups; except for pain palpation in plantar fasciitis group. Significant differences were observed between the two groups for COP area displacement sway (p < 0.01; d = 0.08) and velocity (p = 0.022; d = 0.04), where the fasciitis group reported poorer postural control than control mainly during more challenging balance tasks (semi-tandem, unipodal). Plantar fasciitis group reported a decrease of gait velocity (p < 0.01; d = 0.12), step length (p < 0.01; d = 0.16) and step width (p < 0.01; d = 0.18) when compared to the healthy group across walking speed tests.

CONCLUSIONS

Individuals with plantar fasciitis report poor postural control and changes in walking pattern across three speeds performance.

Predictors of Step Length from Surface Electromyography and Body Impedance Analysis Parameters

Step length is a critical hallmark of health status. However, few studies have investigated the modifiable factors that may affect step length. An exploratory, cross-sectional study was performed to evaluate the surface electromyography (sEMG) and body impedance analysis (BIA) parameters, combined with individual demographic data, to predict the individual step length using the GAITRite® system. Healthy participants aged 40−80 years were prospectively recruited, and three models were built to predict individual step length. The first model was the best-fit model (R2 = 0.244, p < 0.001); the root mean square (RMS) values at maximal knee flexion and height were included as significant variables. The second model used all candidate variables, except sEMG variables, and revealed that age, height, and body fat mass (BFM) were significant variables for predicting the average step length (R2 = 0.198, p < 0.001). The third model, which was used to predict step length without sEMG and BIA, showed that only age and height remained significant (R2 = 0.158, p < 0.001). This study revealed that the RMS value at maximal strength knee flexion, height, age, and BFM are important predictors for individual step length, and possibly suggesting that strengthening knee flexor function and reducing BFM may help improve step length.

Study of Anthropometric and Body Composition Variables in the Overweight/Obese, Sedentary Elderly Men Using WATERinMOTION Aqua Training: A cross-Sectional Study

Background: The effect of aqua training on human body composition still causes inconsistency. Objectives: This study was set to identify the effects of WATERinMOTION (WiM) as a water-based exercise on anthropometric and body composition variables without dietetic supervision in overweight/obese, sedentary elderly men. Methods: Participants (n = 70; age: 70.5 ± 4.4 years) derived by purposive and accessible selection were randomly distributed to either a one-month WiM aqua training group (n = 35, two weekly sessions each included 55 minutes on WiM aqua training) or a control group (n = 35, at the same time in sitting state). Anthropometric measures (height, weight, and waist circumference [WC]) and body composition variables (body mass index [BMI], fat mass [FM], total body water [TBW], and free fat mass [FFM]) were evaluated pre/post-study. Results: Upon analysis, statistically significant changes (P ≤ 0.05) were set on weight, BMI, and FM by comparing pre/post study for the WiM group. Furthermore, comparing groups at post disclosed a significant change in anthropometric measures (weight and WC) and body composition variables (BMI, FM, TBW, and FFM). Conclusions: A short-run, non-diet-supervised WiM program suggests supporting a loss in weight, FM, and BMI in overweight/obese, sedentary elderly men.

The Impact of Parkinson's Disease on Postural Control in Older People and How Sex can Mediate These Results: A Systematic Review

INTRODUCTION

Parkinson's disease is most prevalent among elderly people, 65 years and over, and leads to an alteration in motor control associated with postural instability. Current evidence shows that postural control decreases with the aging process. In addition, postural control is more altered in healthy aged men than in women. Until today, few studies have evaluated the combined impact of Parkinson's disease and sex on postural control. This review has allowed to evaluate the impact of Parkinson's disease and sex on postural control measurements in elderly people.

METHODOLOGY

Studies have been selected from two main databases: PubMed and EBSCO using the keywords "Parkinson", "postural control OR balance" and "sex". Articles related to the evaluation of postural control, including men and women with Parkinson's aged over 65 years old, regardless of stage, were included (n = 179). Articles were excluded if not written in French or English or not presenting original content.

RESULTS

Ten (10) studies out of 179 that fulfilled inclusion and exclusion criteria were reported in the final analysis, which cumulates a total of 944 individuals with Parkinson's (410 women). In general, results show greater postural instability among people with Parkinson's compared to healthy subjects, and this according to different objective measurements using stabilographic parameters from force platforms. Only two studies out of ten evaluated postural control while briefly considering distinctions between sex, but without showing a significant difference between men and women with Parkinson's. Parkinson's severity, length of time of Parkinson's disease and cognitive state of the person are the three variables with a negative impact on postural control.

CONCLUSION

Older people with Parkinson's disease have greater postural instability. Sex does not seem to influence the postural control of elderly people with Parkinson's, although more studies are necessary.

Association between Anthropometric Variables, Sex, and Visual Biofeedback in Dynamic Postural Control Assessed on a Computerized Wobble Board

Anthropometrics and sex influence balance performances, and visual information can change anthropometrics’ relation and the postural sway. Therefore, the aim of the present study was to evaluate the effect of anthropometric characteristics, sex, and visual biofeedback and/or their interaction on a computerized wobble board. Twenty-seven (14 females, 13 males) young adults performed three 30-s double leg stance trials on a wobble board during two conditions: with visual and without visual biofeedback. Visual biofeedback improved (p = 0.010) balance on a wobble board with respect to the condition without visual biofeedback. Regardless of sex, no differences between conditions were found (p = 0.088). When investigating the effect of anthropometrics variables, sex, and their interactions on conditions, a significant main effect of the lower limb/height ratio, sex, and their interaction on the condition without visual biofeedback was found (p = 0.0008; R2 = 0.57). For the visual biofeedback condition, significant effects for sex and body mass (p = 0.0012; R2 = 0.43) and sex and whole-body moment of inertia (p = 0.0030; R2 = 0.39) were found. Results from the present study showed (1) visual biofeedback improved wobble board balance performance; (2) a significant main effect of lower limb/height ratio, sex, and their interaction on the wobble board performances without visual biofeedback emerged; (3) significant effects were found for sex and body mass and sex and moment of inertia in the visual biofeedback condition. Findings from the present study could have an impact on training and evaluations protocols, especially when several populations such as children, athletes, older adults and people with balance disorders are involved.

Equimetrix Device: Criteria Based Validation and Reliability Analysis of the Center of Mass and Base of Support of a Human Postural Assessment System

Human postural control is a fundamental ability for static and dynamic tasks, especially in hiper- and hipo-functional populations, such as the elderly. The Equimetrix is a clinical device developed to assess both the base of support (BoS) and the center of mass (CoM) dynamics, thus allowing their use as new evaluation and training tools. This study aims to perform a criteria based validation of Equimetrix by comparing the BoS and CoM data with gold-standard equipment. A motion capture system, force platform, and pressure mat were used to calculate the CoM, center of pressure (CoP) and BoS during bipedal, unipedal, feet together and full tandem stances. Results demonstrate an excellent reliability of Equimetrix in terms of spatial accuracy of the CoM, although over-estimating the CoM height. Differences were found when comparing Mean velocity Path with the CoM, but not with the CoP, indicating a lower reliability in time-based parameters. The Equimetrix presents a tendency to overestimate the BoS, with mixed reliability values, which may be related to the different size of sensing elements between the Equimetrix and the pressure sensing mat. These are encouraging results that should be further explored during dynamic tasks.

Standard reference values of weight and maximum pressure distribution in healthy adults aged 18-65 years in Germany

Background

The aim of this study was to collect standard reference values of the weight and the maximum pressure distribution in healthy adults aged 18–65 years and to investigate the influence of constitutional parameters on it.

Methods

A total of 416 healthy subjects (208 male / 208 female) aged between 18 and 65 years (Ø 38.3 ± 14.1 years) participated in this study, conducted 2015–2019 in Heidelberg. The age-specific evaluation is based on 4 age groups (G1, 18–30 years; G2, 31–40 years; G3, 41–50 years; G4, 51–65 years). A pressure measuring plate FDM-S (Zebris/Isny/Germany) was used to collect body weight distribution and maximum pressure distribution of the right and left foot and left and right forefoot/rearfoot, respectively.

Results

Body weight distribution of the left (50.07%) and right (50.12%) foot was balanced. There was higher load on the rearfoot (left 54.14%; right 55.09%) than on the forefoot (left 45.49%; right 44.26%). The pressure in the rearfoot was higher than in the forefoot (rearfoot left 9.60 N/cm², rearfoot right 9.51 N/cm²/forefoot left 8.23 N/cm², forefoot right 8.59 N/cm²). With increasing age, the load in the left foot shifted from the rearfoot to the forefoot as well as the maximum pressure (p ≤ 0.02 and 0.03; poor effect size). With increasing BMI, the body weight shifted to the left and right rearfoot (p ≤ 0.001, poor effect size). As BMI increased, so did the maximum pressure in all areas (p ≤ 0.001 and 0.03, weak to moderate effect size). There were significant differences in weight and maximum pressure distribution in the forefoot and rearfoot in the different age groups, especially between younger (18–40 years) and older (41–65 years) subjects.

Discussion

Healthy individuals aged from 18 to 65 years were found to have a balanced weight distribution in an aspect ratio, with a 20% greater load of the rearfoot. Age and BMI were found to be influencing factors of the weight and maximum pressure distribution, especially between younger and elder subjects. The collected standard reference values allow comparisons with other studies and can serve as a guideline in clinical practice and scientific studies.

Posturographic Analysis in the Elderly with and without sensorineural Hearing Loss

Introduction  Sensorineural hearing loss (SNHL) is a serious public health problem. Some evidence suggests a significant relationship between SNHL and balance disorders. The inability to maintain balance associated with SNHL while standing further increases the risk of falls among older people. Objective  To investigate the association between SNHL on the postural balance in elderly individuals of both genders. Methods  The sample consisted of 247 (166 women) physically independent elderly individuals, (mean age = 68.4 ± 6.0). The instruments used were the anamnesis and the pure tone audiometry for hearing loss, and for balance a force platform based in measures of center of pressure area and of sway velocity in the anteroposterior and mediolateral directions. Results  Presence of hearing loss (HL) was observed in 68% of the participants. We observed a significant association between SNHL and characteristics of balance between the groups with and without HL for center of pressure (COP) area ( p  = 0.010), anteroposterior velocity ( p  = 0.001) and mediolateral velocity ( p  = 0.020). There was a significant difference between the gender groups for center of pressure area ( p  = 0.004), anteroposterior velocity ( p  = 0.001) and mediolateral velocity ( p  = 0.001) with better performance in the female group. Amongst men, there was a difference between the ones with HL and those without it, for COP area ( p  = 0.049). Conclusion  In the present study, elderly individuals with SNHL exhibited more instability on the postural balance, and elderly men presented worse results in the test.

Interactions among obesity and age-related effects on the gait pattern and muscle activity across the ankle joint

OBJECTIVE

The purposes of this study were to investigate the combined effects of age and obesity on gait and to analyze the relationship between age and obesity on ankle muscle activities during walking.

MATERIALS AND METHODS

4 groups; the young non-obese control group (CG, n = 50, age = 31.8 ± 4.5 years; BMI = 21.4 ± 2.2 kg/m²), the young obese group (OB, n = 30, age = 35.4 ± 4.1 years; BMI = 38.6 ± 3.5 kg/m²), the non-obese older adults group (OA, n = 20, age = 76.1 ± 3.5 years; BMI = 24.4 ± 1.1 kg/m²) and the obese older adults group (OBOA, n = 20, age = 79.6 ± 5.7 years; BMI = 35.5 ± 2.7 kg/m²) walked on an instrumented gait analysis treadmill at their preferred walking speed. Spatiotemporal parameters, walking cycle phases, Vertical ground reaction force (GRFv) and center of pressure (CoP) velocity were sampled from the treadmill software. Electromyography (EMG) activity of the gastrocnemius medialis (GM), the soleus (SOL) and tibialis anterior (TA) were also collected during the walking test. A forward stepwise multiple regression analysis was performed to determine if body weight or age could predict ankle muscle activities during the different walking cycle phases.

RESULTS

Compared to OB, OBOA walked with higher CoP velocity, shorter stride, spending more time in support phase (p < .05). These manifestations were associated with higher TA and SOL activities during the 1st double support (1st DS) and higher TA activity during the single support (SS) (p < .05). Compared to OA, OBOA walked with lower GRFv, shorter and wider stride and spend more time in SU (p < .05). Moreover, SOL, TA and GM activities of OBOA were higher compared to OAG during 1st DS, SS and 2nd Double support (2nd DS), respectively (p < .05). During the 1ST DS, the stepwise multiple regression revealed that age accounted for 87% of the variance of TA activity. The addition of age contributed a further 16% to explain the variance TA activity. During the SS, age accounted for 64% and 46% of the variance of SOL and TA activity respectively. The addition of the body weight added further 15% and 66% of the variation of SOL and TA activity respectively. During the 2nd DS, body weight accounted for 86% of the variance and the addition of the body weight added a further 17% to explain the high level of GM.

CONCLUSION

Age in obese adults and obesity in older adults should be considered separately to evaluate neuromuscular responses during walking and, subsequently, optimize the modality of treatment and rehabilitation processes in obese individuals in order to reduce and/or prevent the risk of falls.

Determination of critical time points in non-collision incidents of elderly passengers in standing position on urban bus

Objective: Due to the reduced physical ability of elderly, the occurrence of non-collision incidents is higher for these passengers in standing position. Therefore, the purpose of the present study is to determine the critical time points of non-collision incidents using the level of leg muscle activity in elderly standing passengers on urban bus.Methods: To determine the critical time points in the occurrence of non-collision incidents, the level of muscular activity of the standing passengers was analyzed using a surface electromyography (surface EMG) device during the movement scenario of the bus. The results of assessing the leg muscle activity was analyzed in SPSS software.Results: The contraction pattern of the leg muscles in standing passengers was consistent with Newton's First Law. The results showed that the level of muscular activity decreased in the right leg muscles when changing the phase of bus motion from acceleration to constant velocity. This level of muscular activity in the left leg muscles increased when constant velocity changed to deceleration. These changes were quite significant in the medial gastrocnemius and soleus muscles (P < 0.05).Conclusions: According to these findings, it was found that the acceleration and deceleration phases, especially the starting and changing phases of bus motion, are the most critical time points in the occurrence of non-collision incidents in elderly standing passengers on urban bus.

Influence of Obesity and Impact of a Physical Activity Program on Postural Control and Functional and Physical Capacities in Institutionalized Older Adults: A Pilot Study

Objective: To evaluate the role of obesity in the effects of physical activity (PA) on postural control and functional and physical capacities in the older adults and to assess the effectiveness of a PA program on these capacities. Methods: Six obese (age = 78.8 [3.7] y; body mass index > 30 kg/m2), 7 overweight (age = 80.9 [2.8] y; 25 < body mass index < 30 kg/m2), and 6 normal weight (age = 80.8 [5.7] y; body mass index < 25 kg/m2) older adults performed the time up and go test, the 6-minute walk test, and the Tinetti test. Static and dynamic (forward leaning) postural control tests were also assessed. All these tests were similarly assessed 4 months later, during which only the obese group and overweight group participated in a PA program. Results: Before PA, results of the time up and go test, 6-minute walk test, Tinetti test, quiet standing, and forward lean tests revealed that physical capacities and static and dynamic postural control were impaired in the obese group when compared to the normal weight group. After PA, results of quiet standing, physical and functional tests were improved for obese group. Conclusions: Obesity is an additional constraint to age-related postural control and functional and physical capacities deteriorations. Nevertheless, a PA program is effective in improving balance and functional capacities in obese older adults.

Effects of physical activity and smoking on cardio-ankle vascular index, respiratory muscle strength, and exercise performance in early normal weight adulthood: a cross-sectional study

Few studies have shown the impact of unhealthy habits on arterial stiffness, respiratory muscle strength and exercise performance in early normal weight adulthood. This study sought to determine the effects of physical activity and smoking on its parameters in normal weight male participants. Forty-eight participants were divided into four groups: physically inactive nonsmokers and smokers and physically active nonsmokers and smokers (n=12 in each group). All of the participants were measured for body composition, arterial stiffness, respiratory muscle strength and exercise performance. Two-way analysis of variance design was used to test the main and interaction effects of physical activity by group (smokers vs. nonsmokers). P-value of less than 0.05 was considered as a statistically significant difference. As a result, cardio-ankle vascular index and respiratory muscle strength were diminished in smokers and physically inactive participants, while body and visceral fat mass were increased in both those groups. Fat-free mass was lower in only physically inactive participants. This study also found the interaction effects on body fat and arterial stiffness. In conclusion, participants with healthy normal weight, but smoked and performed inappropriate physical activity, exhibited body composition imbalance, decreased respiratory muscle strength, exercise performance, and increased arterial stiffness. Therefore, smoking cessation and exercise in younger adults are appropriate ways of improving body composition, respiratory muscle strength, aerobic capacity and arterial stiffness instead of trying to control their weight by smoking.

Effects of obesity on postural balance and occurrence of falls in asymptomatic adults

Abstract Introduction: Previous studies suggested that body weight is a strong predictor for postural balance. High body mass index (BMI) presented an association with increased postural sway. However, it seems controversial since studies reported no difference between obese and control group regarding the position of the center of pressure in static postural balance (PB). Also, there is a lack of investigations about the impact of obesity on PB, free of the confound effect of cardiometabolic risk. Objective: The aim of this study was to evaluate the effects of obesity in static PB and occurrence of falls in asymptomatic adults and older adults over 40 years old. Method: The PB of 624 subjects divided into quartiles for BMI, waist-to-hip ratio, waist-to-height and fat body mass as percentage (%FBM) was assessed with and without vision using a force platform. An MANOVA was used to determine if there were differences between quartiles and a logistic regression analysis adjusted for confounders variables were applied to determine the obesity role in the occurrence of falls. Results: We found weak to moderate bivariate correlations between obesity and static PB, which became non-significant after adjustment. We found significant differences between first and fourth quartiles, especially using %FBM. Obesity was not related to the occurrence of falls since the odds ratio values became non-significant for all the indices of obesity after adjustment. Conclusion: Obesity presents little influence on maintaining static PB and seems not to determine the occurrence of falls among subjects over 40 years old.

Y balance test: Are we doing it right?

OBJECTIVES

The multifaceted characteristic and task-specificity of postural control clearly reflects the need of knowing which factors could influence the balance measures in order to provide reliable and unbiased information. Therefore, this study aimed to investigate the effects of selected anthropometric characteristics, sex, lower limb's strength and dominance on the Y balance test (YBT).

DESIGN

Descriptive laboratory study.

METHODS

Forty-two young adults performed the YBT. The raw and normalized reach distances values were recorded. ANOVA was used to examine differences between sex and limb dominance, whereas multiple linear regression models were built to identify variables associated with better postural control.

RESULTS

No significant sex differences were observed, except for the normalized anterior direction (p=0.0324). No significant differences between limbs emerged. Regression models significantly explained between 8-49% of the variance. Trunk length, strength, and the interaction between sex with strength were the major predictors of the raw measures. Unexpectedly, lower limb length explained only 0.08% of the raw anterior direction variance. Strength and its interaction with sex were positively associated with normalized measures. Surprisingly, the relative lower limb length variable was negatively associated with the normalized measures. Each % point increase in relative lower limb length was associated with a decrease in normalized performance ranging from 1.73 to 4.91%.

CONCLUSIONS

Anthropometric characteristics, sex and lower limb strength differently influenced the YBT measures, regardless of limb dominance. Consequently, these variables should be controlled to limit the variability for an accurate evaluation of postural balance, especially if different YBT measures are used.

Walking and postural balance in adults with severe short stature due to isolated GH deficiency

OBJECTIVES

Walking and postural balance are extremely important to obtain food and to work. Both are critical for quality of life and ability to survive. While walking reflects musculoskeletal and cardiopulmonary systems, postural balance depends on body size, muscle tone, visual, vestibular and nervous systems. Since GH and IGF-I act on all these systems, we decided to study those parameters in a cohort of individuals with severe short stature due to untreated isolated GH deficiency (IGHD) caused by a mutation in the GHRH receptor gene. These IGHD subjects, despite reduction in muscle mass, are very active and have normal longevity.

METHODS

In a cross-sectional study, we assessed walking (by a 6-min walk test), postural balance (by force platform) and fall risk (by the 'Timed Up and Go' test) in 31 IGHD and 40 matched health controls.

RESULTS

The percentage of the walked distance measured in relation to the predicted one was similar in groups, but higher in IGHD, when corrected by the leg length. Absolute postural balance data showed similar velocity of unipodal support in the two groups, and better values, with open and closed eyes and unipodal support, in IGHD, but these differences became non-significant when corrected for height and lower-limb length. The time in 'Timed Up and Go' test was higher in IGHD cohort, but still below the cut-off value for fall risk.

CONCLUSION

IGHD subjects exhibit satisfactory walking and postural balance, without increase in fall risk.

One-legged stance sway of older adults with and without falls

Postural instability is a common problem among older people, and it is associated with mobility impairments, activity limitation and fear of falling. The evaluation of postural control can contribute to the early detection of balance deficits and help health professionals to manage this problem to prevent falls in older adults. The aim of this study was to identify center of pressure cut-offs to differentiate between older adults with and without falls in the past 12 months. The participants were 170 older adults (mean age 67 years, 50 fallers and 120 non-fallers). Center of pressure area and sway velocity in the anterior-posterior and medio-lateral directions were assessed using a force platform during three 30s one-legged stance trials with eyes open. The mean across trials was used for analysis. The time-limit (how long the participant was able to stay in one-legged stance, up to 30s) was also assessed. Fallers had poorer postural control than non-fallers (effect size ≥ 0.52, P <0.05). The cut-offs identified were 10.3 cm² for Center of pressure area, 2.9 cm/s for velocity in the anterior-posterior, and 3.4 cm/s for medio-lateral velocity. The force platform parameters obtained an area under the curve of 0.72, with sensitivity of 78% and specificity of 68%. There were no significant differences between non-fallers and fallers for time-limit variable (17 seconds vs. 18 seconds). Force platform parameters during one-legged stance were associated with history of falls in older adults. The cut-offs obtained acceptable area under curve, sensitivity and specificity, with center of pressure area presenting the best performance to differentiate between fallers and non-fallers.