Go Across Immersive Technology: A Preliminary Study of the Design and Development of a System for Gait Training Using Virtual Reality

Virtual reality (VR) allows visuotactile interaction in a virtual environment. VR has several potential applications such as surgical training, phobia treatments, and gait rehabilitation. However, further interface development is required. Therefore, the objective of this study was to develop a noninvasive wearable device control to a VR gait training program. It consists of custom-made insoles with vibratory actuators, and plantar pressure sensor-based wireless interface with a VR game. System usability testing involved a habituation period and three gaming sessions. Significant gait improvement was associated with game scores (P < 0.05). This VR gait training system allowed real-time virtual immersive interaction with anticipatory stimulus and feedback during gait.

Independent and joint associations of cardiorespiratory fitness and lower-limb muscle strength with cardiometabolic risk in older adults

The aim of this study was to investigate the independent and joint associations of low cardiorespiratory fitness and lower-limb muscle strength with cardiometabolic risk in older adults. A total of 360 community-dwelling older adults aged 60-80 years participated in this cross-sectional study. Cardiometabolic risk was based on the diagnosis of Metabolic Syndrome and poor Ideal Cardiovascular Health according to the American Heart Association guidelines. Cardiorespiratory fitness and lower-limb muscle strength were estimated using the six-minute walk and the 30-second chair stand tests, respectively. Participants in the 20th percentile were defined as having low cardiorespiratory fitness and lower-limb muscle strength. Poisson's regression was used to determine the prevalence ratio (PR) and 95% confidence intervals (CI) of Metabolic Syndrome and poor Ideal Cardiovascular Health. Participants with low cardiorespiratory fitness alone and combined with low lower-limb muscle strength were similarly associated with a higher risk for Metabolic Syndrome (PR 1.27, 95% CI 1.09-1.48, and PR 1.32, 95% CI 1.10-1.58, respectively), and poor Ideal Cardiovascular Health (PR 1.76, 95% CI 1.25-2.47, and PR 1.65, 95% CI 1.19-2.28, respectively). Low lower-limb muscle strength alone was not associated with a higher risk for either Metabolic Syndrome or poor Ideal Cardiovascular Health (PR 1.23, 95% CI 0.81-1.87, and PR 1.11, 95% CI 0.89-1.37, respectively). Low cardiorespiratory fitness alone or combined with low lower-limb muscle strength, but not low lower-limb muscle strength alone, was associated with a higher cardiometabolic risk in older adults. The assessment of physical fitness may be a "window of opportunity" to identify youngest-old adults with a high cardiovascular disease risk.

Modeling Cues May Reduce Sway Following Sit-To-Stand Transfer for People with Parkinson's Disease

Cues are commonly used to overcome the effects of motor symptoms associated with Parkinson's disease. Little is known about the impact of cues on postural sway during transfers. The objective of this study was to identify if three different types of explicit cues provided during transfers of people with Parkinson's disease results in postural sway more similar to healthy controls. This crossover study had 13 subjects in both the Parkinson's and healthy control groups. All subjects completed three trials of uncued sit to stand transfers. The Parkinson's group additionally completed three trials of sit to stand transfers in three conditions: external attentional focus of reaching to targets, external attentional focus of concurrent modeling, and explicit cue for internal attentional focus. Body worn sensors collected sway data, which was compared between groups with Mann Whitney U tests and between conditions with Friedman's Tests. Sway normalized with modeling but was unchanged in the other conditions. Losses of balance presented with reaching towards targets and cueing for an internal attentional focus. Modeling during sit to stand of people with Parkinson's disease may safely reduce sway more than other common cues.

Relationship between inspiratory muscle strength and balance in women: A cross-sectional study

BACKGROUND

There is scarce evidence on changes at the functional level associated with the respiratory area in women. This study aims to analyse the relationship between inspiratory muscle strength and balance in women.

MATERIAL AND METHODS

In this cross-sectional observational study, the sample consisted of groups according to the results obtained in the balance test. Inspiratory muscle weakness was defined as maximum inspiratory pressure (MIP) ≤ 80% of the predictive value. MIP was carried out using through a mouthpiece, with an electronic manometer. Logistic regression model was used to examine if MIP predicts balance.

RESULTS

159 women participated in the study. Approximately 20% of them achieved balance ≤ 2 seconds and 18% presented MIP≤80%. MIP was associated with the time achieved in the one-leg support test. Subjects with MIP ≤ 80% of the predictive value show 3 times more risk of having a lower performance in the balance test (OR = 3.26).

CONCLUSIONS

Inspiratory muscle weakness is associated with deficient balance in this sample. It shows the need for multidimensional assessment and rehabilitation strategies for patients identified as having MIP weakness and/or balance disorders.

Older Adults' Vigorous Occupational Physical Activity Levels in Six Countries Are Explained by Country and 'Having Multiple Jobs'

Several studies have compared physical activity (PA) levels between countries, but none of these studies focused on older adults and occupational PA. This study aimed to assess potential inequalities in older adults' occupational PA across six countries and to ascertain whether having multiple jobs is a factor that interacts with country of residence to modify inequalities. This study adopted a cross-sectional design with a statistical technique screening for potential covariates. Older adults (mean age = 64 years; range = 50-114 years) from six countries (Russia, Mexico, China, India, Ghana, and South Africa) participated in the study. We utilised data from the first wave of the Study on Global AGEing and Adult Health (SAGE). These data were collected from 2007 to 2010. A random sample of 34,114 older adults completed the survey. We analysed the data with a two-way multivariate analysis of variance after screening for the ultimate covariates. There were differences in occupational PA levels (i.e., vigorous and moderate PA) among the six countries. Occupational PA levels were not significantly associated with having multiple jobs. However, having multiple jobs interacted with country of residence to influence vigorous occupational PA. Older adults from most countries who had more than one job reported more vigorous occupational PA. Older adults' occupational PA differed among the six countries, and having multiple jobs was associated with more vigorous occupational PA. Older adults who keep multiple jobs at a time may be more active than their counterparts who had one job or were unemployed.

Does 8-Week Resistance Training with Slow Movement Cadenced by Pilates Breathing Affect Muscle Strength and Balance of Older Adults? An Age-Matched Controlled Trial

This study investigated the balance and dorsiflexion strength of older adults after eight weeks of resistance training, with the exercise velocity cadenced by the Pilates breathing technique and the volume modulated by the session duration. Forty-four older adults were divided into two groups: resistance training (TR; n = 22) and resistance training with the Pilates breathing technique cadencing all exercises (TR + P; n = 22), both during eight weeks. The total exercising volume was controlled by time of execution (50 min/session). The dorsiflexion strength and balance were assessed. The RT group showed higher dorsiflexion strength after the protocol: Right (RT = 29.1 ± 7.7 vs. RT + P = 22.9 ± 5.2, p = 0.001) and Left (RT = 29.5 ± 6.9 vs. RT + P = 24.0 ± 5.2, p = 0.001). All balance parameters were improved in RT + P group compared to its own baseline: Path Length (cm) (pre = 71.0 ± 14.3 vs. post = 59.7 ± 14.3, p = 0.003); Sway Velocity (cm/s) (pre = 3.6 ± 0.7; post = 2.9 ± 0.7; p = 0.001); Sway Area (cm²) (pre = 8.9 ± 5.3 vs. post = 5.7 ± 2.1, p = 0.003); Excursion Medio Lateral (cm) (pre = 3.0 ± 0.7 vs. post = 2.6 ± 0.5 cm, p = 0.002); and Excursion AP (cm) (pre = 3.6 ± 1.4 vs. post = 2.8 ± 0.7 cm, p = 0.010). Resistance training using slower velocity movement cadenced by Pilates breathing technique produced balance improvements compared to baseline (moderate to large effect sizes), but no between-group effect was observed at the end of the protocol. The dorsiflexion strength was higher in the RT group compared to RT + P group.

Adaptation of Anaerobic Field-Based Tests for Wheelchair Basketball Athletes

Purpose: The aim of this study was to propose field-based tests to estimate the anaerobic power of wheelchair basketball athletes. Methods: Eleven lower class wheelchair basketball players performed the Wingate test (WT) and two field-based tests (repeated sprints) of 15 (S-15) and 20 (S-20) meters. The WT provides data in Watts (W). The S-15 and S-20 are recorded in seconds and converted to W using the Running-based Anaerobic Sprint Test (RAST) equation. The participants also completed other field-based tests, such as right and left handgrip strength (HGS) tests and the medicine ball chest pass test. In addition, body mass and height were measured, and the body composition was estimated. The field-based tests and anthropometric measures were used to estimate WT peak power (PP) and mean power (MP) using multiple linear regressions. Results: The field-based tests underestimated the anaerobic power measured with the WT (in W). However, a linear regression model based on S-15 PP, right HGS, height, and body mass explained 76% (P= .040) of the WT PP variance. Another model based on S-15 MP and right HGS explained 72% (P= .006) of the WT MP variance. Both models had excellent reliability (ICC > 0.90). Conclusion: WT PP can be estimated using S-15 PP (W), right HGS, height, and body mass. The WT MP is predicted using S-15 MP (W) and right HGS. Therefore, a combination of field-based tests and anthropometric measures seem to be appropriate to determine anaerobic power of lower class wheelchair basketball athletes.

What is the traditional method of resistance training: a systematic review

BACKGROUND

Many resistance studies state that they used the traditional method of resistance training in the intervention. However, there is a wide difference on the characteristics of the training protocols used even though they are labeled as "the traditional method". There is no clear definition and characteristics for the traditional method of resistance training.

OBJECTIVE

To describe the most common definitions and references, and also the main characteristics of the training variables of the studies using the traditional training method for strengthening.

DATABASE

Searches were carried out in Pubmed, Embase, SPORTDiscus and Web of Science.

STUDY SELECTION

We included randomized controlled trials that included a strengthening program using the "traditional method" and that evaluated hypertrophy and/or maximum strength in healthy individuals.

RESULT

The initial search resulted in 26,057 studies, but only 39 studies were eligible and included in this review. The common characteristics of the traditional training protocol were frequency of 3 sessions/week, 3 sets of 9 repetitions, with weight = 75% 1RM. The movement time was 2±1 seconds for the concentric and for the eccentric phases. Resting time between sets was 2±1 minutes. The concepts used to define the method as traditional and the characteristics of the intervention protocols were different. The American College of Sports Medicine (ACSM) was the most cited reference.

CONCLUSIONS

The "traditional method of resistance training" can be defined as: "Three (±1) sets of 9±6 repetitions of concentric and eccentric exercises using an external load of 75±20% of one maximum repetition, completed 3±1 times/week.

Eight-week equipment-based Pilates exercises positively affects quality of life, and functional capacity in non-active adult women: a randomized controlled trial

BACKGROUND

The Pilates exercises are popular for muscle conditioning among women. However, the effects on conditioning of healthy non-active adult women due to Pilates practicing are not fully explained. The aim of this randomized controlled trial was to assess the effects of equipment-based Pilates exercises on the percentage of body fat, weight, body mass index (BMI), functional capacity, and quality of life of adult healthy women.

METHODS

Seventy-eight non-active women were randomly assigned to 2 groups (Pilates or Control). The Pilates group performed a total of 16 exercise sessions (60 minutes each, performed twice a week for 8 consecutive weeks). The control group was instructed to perform no exercise. Percentage of body fat (DXA scans), weight, BMI, distance covered in the incremental shuttle walk test, maximal oxygen uptake (VO<inf>2max</inf>), and quality of life (SF-36 scores) were analyzed.

RESULTS

There were no significant between-group differences at baseline, but significant group-by-time interaction was observed for Pilates group postintervention. Higher distance covered (P=0.01), VO<inf>2max</inf> (P=0.04), and quality of life (P=0.04) were observed after the intervention compared to the control group. No differences were observed for body composition.

CONCLUSIONS

Two months of equipment-based Pilates training improved functional capacity and quality of life in healthy adult women.

Using Augmented Reality with Older Adults in the Community to Select Design Features for an Age-Friendly Park: A Pilot Study

Sedentary behavior is prevalent in older adults. Older adults often underutilize public parks for exercising because the parks do not support their needs and preferences. Engaging older adults on the redesign of parks may help promote active lifestyles. The objectives of this pilot study were to evaluate (1) the effects of wearing augmented reality (AR) and virtual reality (VR) glasses on balance; (2) the effects of different virtual walls separating the walking trail from the roadway on older adults' gait, and (3) the preferences of the participants regarding wall design and other features. The participants were ten older adults (68 ± 5 years) who lived within two miles from the park. Balance and gait were assessed using a force plate and an instrumented mat. It was feasible to use AR with older adults in the park to evaluate features for redesign. Motion sickness was not an issue when using AR glasses, but balance was affected when wearing VR goggles. The area of postural sway increased approximately 25% when wearing AR glasses, and it increased by close to 70% when wearing VR goggles compared to no glasses. This difference is clinically relevant; however, we did not have enough power to identify the differences as statistically significant because of the small sample size and large variability. Different walls did not significantly affect the participants' gait either because they did not alter the way they walked or because the holograms were insufficiently realistic to cause changes. The participants preferred a transparent wall rather than tall or short solid walls to separate the park from the roadway.

Effectiveness of exergames for improving mobility and balance in older adults: a systematic review and meta-analysis

BACKGROUND

Exergaming is a fun, engaging, and interactive form of exercising that may help overcome some of the traditional exercise barriers and help improve adherence on the part of older adults, providing therapeutic applications for balance recovery and functional mobility. The purpose of this systematic review is to summarize the effects of exergames on mobility and balance in older adults.

METHODS

The PRISMA guidelines for systematic reviews were followed. The following databases were searched from inception to August 2019: Cochrane Central Register of Controlled Trials, MEDLINE, EMBASE, PEDro, CINAHL, and INSPEC. We selected randomized controlled trials that assessed the effects of exergames on balance or mobility of older adults without neurological conditions, in comparison to no intervention or health education. Two review authors independently screened the trials' titles and abstracts and identified trials for inclusion according to the eligibility criteria. An almost perfect agreement between the authors was observed with respect to interrater reliability of trial selection (kappa = 0.84; P < 0.001). We performed descriptive analysis of the quantitative data to summarize the evidence. Meta-analysis was carried out using RevMan. A random effects model was used to compute the pooled prevalence with 95% confidence intervals.

RESULTS

After screening 822 records, 12 trials comparing exergames with no intervention were included. A total of 1520 older adults participated in the studies, with a mean age of 76 ± 6 years for the experimental group and 76 ± 5 years for the control group. Quantitative synthesis showed significant improvements in balance and mobility based on the center of pressure sway (SMD = - 0.89; 95%CI = - 1.26 to - 0.51; P = 0.0001; I² = 58%), Berg Balance Scale (MD = 2.15; 95%CI = 1.77 to 2.56; P = 0.0001; I² = 96%), and on Timed Up and Go test (MD = - 2.48; 95%CI = - 3.83 to - 1.12; P = 0.0003; I² = 0).

CONCLUSIONS

Exergames improved balance and mobility in older adults without neurological disorders and motivate patients to keep performing balance exercises. High quality studies with standardized assessment protocols are necessary to improve the strength of the evidence.

Vestibular function in severe GH deficiency due to an inactivating mutation in the GH-releasing hormone receptor gene

PURPOSE

Body balance involves the vestibular, visual, and proprioceptive systems. IGF-I is a GH-dependent key factor in the development and postnatal differentiation of the inner ear in mice and men, but its role in the vestibular function in adult humans is unknown. We have previously described a cohort of individuals with severe isolated GH deficiency (IGHD) caused by a mutation in the GHRH receptor (GHRHR) gene. These individuals complain of dizziness, exhibit mild sensorineural loss, but have normal postural balance, without increase in falls risk. The aim of this study was to evaluate their vestibular function.

METHODS

We performed physical examination (clinical head impulse and Fukuda dynamic stepping test), oculomotor (saccadic eye movements, spontaneous, semi-spontaneous and opotokinetic nystagmus, and pendular tracking) and caloric stimulation (postcaloric reflex and ocular fixation index) tests, in 15 GH-naïve IGHD (seven males) and 15 controls (five males).

RESULTS

IGHD subjects showed lower height and weight, with similar BMI to controls, and higher number of individuals with abnormal clinical head impulse test and abnormal oculomotor tests, namely the saccadic movements and the spontaneous nystagmus. There was a nonsignificant trend in abnormalities in the Fukuda stepping test and postcaloric reflex test.

CONCLUSIONS

Adult untreated IGHD individuals have higher prevalence of moderate peripheral vestibular impairment, and of abnormal vestibular-ocular reflex.

Increasing Protein Intake to Help Older Adults Increase Muscle Strength and Function: A Pilot, Single-Arm Investigation Using Coaching and a Per-Meal Protein Prescription

Objective

To evaluate the effects of nutrition education, diet coaching, and a protein prescription (PP) on protein intake, and associations with muscle strength and function.

Design

Prospective pretest posttest single-arm study.

Setting

Urban area, East coast of South Florida. Participants: 20 white, non-Hispanic adults, aged 73.3 + 10.4 years.

Intervention

10-week telephone-based diet coaching, nutrition education and a per-meal PP.

Measurements

Protein and energy intakes, weight, grip strength (GS), and 5-chair-rise (5CR), timed up and go (TUG), 3-meter walk (3mW) tests at baseline and 10 weeks.

Results

Pre to 10-week post values significantly improved (p<0.05) for protein intake/kg body weight (0.8 + 0.3 to 1.2 + 0.3g), protein intake/meal (17.2 ± 4.8g to 26.4 ± 6.g), protein intake/100 kcal (3.74 + 1.16 to 5.97 + 0.98g), GS (22.4 to 23.4kg), and times for TUG (10 to 8sec), 3mW (4 to 3sec), and 5CR (13 to 11sec).

Conclusions

Given the positive findings of this unique pilot investigation, additional studies, which include a larger more diverse group of participants and provide for control group(s), are needed to better investigate the effectiveness of this approach and its effects on muscle strength and function.

EFFECT OF CHAIR YOGA ON FRAILTY IN OLDER ADULTS WITH LOWER EXTREMITY OSTEOARTHRITIS: RANDOMIZED CLINICAL TRIAL

This study examined whether chair yoga (CY) could reduce severity of frailty in community-dwelling older adults with lower extremity osteoarthritis (OA). Participants were randomly assigned to CY or health education program (HEP) at each of two sites and attended twice-weekly 45-minute sessions for 8 weeks. Data were collected at baseline and 4 and 8 weeks. For primary analysis, followed by Rockwood’s suggesiton, 97 deficits/variables measuring OA symptoms, physical function, balance, fatigue, depression, social activities, and life satisfaction were used to construct a frailty index, ranging from 0 to 1. Fewer deficits/variables were used to construct three alternative versions of the index. Linear mixed-effects models with random intercept were used to analyze longitudinal repeated outcome measures. A total of 112 participants (n = 63 CY, n = 49 HEP; 75.3[7.5] years; 76% female, 46% Hispanic) completed the study. After adjusting for site, cohort effect, and baseline of frailty, there was no significantly greater decline in frailty in the CY group compared to the HEP group (between-group difference, -0.019; 95% CI, -0.063 to 0.025) or the trend of changes in the index (p for interaction = .489). Additional adjustment for baseline characteristics (age, gender, ethnicity, marital status, living alone, health status, pain medication) did not change results substantially. Secondary analysis of three alternative versions of the index indicated similar nonsignificant changes. Thus, an 8-week CY intervention did not reduce severity of frailty in older adults with lower extremity OA. A longer duration of CY with a larger sample size is needed.

DOES WEARING AUGMENTED-REALITY GOGGLES AFFECT OLDER ADULTS’ KINEMATICS DURING GAIT?

Virtual-reality (VR) testing can cause motion sickness and impair safety, especially for older adults, but augmented-reality (AR) may allow the testing of holograms embedded into a mixed-reality environment without the VR impediments. However, wearing AR googles may affect the way people walk, but this possibility has not being tested. The objective of this study was to evaluate if wearing AR googles during gait would affect the kinematics of older adults. Ten older adults (68±5 years), who could walk without assistive devices, participated in this study. The participants walked outdoors in a public park with and without the AR googles. The participants were instrumented inertial movement units to track their kinematics (MTw Awinda trackers, Xsens Technologies B.V., Enschede, the Netherlands). The goal of the study was to assess if simply wearing the googles would affect gait, therefore no holograms were displayed. Ten gait cycles were analyzed and the mean of each subject was used to compare the joint kinematics between the conditions (with vs without googles) using T-tests in SPSS 18. The foot, ankle, knee and hip angles were not different between the conditions (p&gt;0.05), but there were significantly less trunk flexion at 44% of the gait cycle (p=0.035) and less forward head flexion throughout the gait cycle (p=0.023) when the participants were wearing the googles vs. when they were not. The findings indicate that wearing AR goggles changed the trunk and head posture cycle, but did not affect the lower limb kinematics during gait.

ONE-LEGGED STANCE BALANCE OF OLDER ADULTS WITH AND WITHOUT FALLS

Balance impairment is a common problem among older adults. Poor balance in older adults is often associated with mobility impairments, activity limitations and fear of falling in older adults. Thus, balance assessment is useful for early detection of postural control deficits to prevent mobility impairments and falls in older adults. The aim of this study was to assess if balance measures based in center of pressure (COP) parameters during one-legged stance could differentiate between older adults with and without falls in the past 12 months. One-hundred and seventy older adults (50 fallers and 120 non-fallers, age range: 63-72 years) performed three 30s one-legged stance trials with eyes open on a force platform with 30s of rest between each trial. The following variables were evaluated: COP 95% elliptical area, COP velocity in the anterior-posterior and medio-lateral directions, and test duration (how long the participant was able to stay in one-legged stance, up to 30s). Fallers had poorer balance than non-fallers (P ≤0.004). The COP parameters presented an area under the curve between 0.65-0.72, with sensitivity varying from 66 to 78% and specificity from 54 to 68%. There were no significant differences between fallers and non-fallers on test duration (17 vs. 18s, respectively). The findings showed that the fallers had similar duration time, but poorer balance than the non-fallers during one-legged stance. The COP parameters were able to differentiate the balance between fallers and non-fallers with acceptable area under curve, sensitivity and specificity.

RISK FACTORS FOR FALLS IN OLDER ADULTS WITH TYPE 2 DIABETES

The objective of this study was to evaluate the probability of the risk of falls in the older adults with type 2 diabetes. One-hundred and eleven older adults (age: 69±7 years) with type 2 diabetes participated in this cross-sectional observational study. The participants sociodemographics, physical function, cognitive status (Mini Mental State Exam – MEEM and Geriatric Depression Scale – GDS), balance (Mini BEST test), functional performance (WHODAS 2.0) and falls risk (Quick Screen Clinical Falls Risk Assessment – QuickScreen) were evaluated. The data was analyzed using the Kruskall-Wallis, Chi-square, and Fisher’s exact tests (p<0.05). Thirty percent of the participants had fallen during the previous 12 months, and 80% of the participants reported fear of falling. The average number of falls risks was 3.5±2. Increased number of falls risks were associated with lower educational level (p=0.005), poorer general health (p=0.001), vision impairment (p=0.017), higher number of diseases (p<0.0001), higher number of medications (p<0.0001), longer diabetes duration (p<0.0001), lower limb pain (p<0.0001), depression (p<0.001), worse functional performance (p<0.0001), and worse balance (p<0.0001). Older adults with type 2 diabetes with lower education, worse health and vision, greater number of diseases and medications, longer diagnosis of diabetes, lower limb pain, depressive symptoms, worse functional performance and balance presented more risks for falls.

IS THERE A RELATIONSHIP BETWEEN PAIN AND FEAR OF FALLING IN OLDER ADULTS LIVING IN LONG-TERM CARE FACILITIES?

Fear of falling is common in older adults and it is associated with multiple factors such as gait and balance issues, difficulties in activities of daily living, visual impairment, and frailty. Unfortunately, fear of falls increases the risk of falls as opposed to protect from falls. Pain can impair mobility, affects activities of daily living, and may also be associated with fear of falling but no studies have evaluated this potential association. The objectives of this study were to evaluate if there was an association between pain and fear of falling in older adults living in long-term care facilities. One hundred and eight older adults living in long-term care facilities participated in the study. The mean age was 79±7 years, and 65% of the participants were women. The participants completed the Geriatric Pain Measure (GPM) questionnaire for multidimensional pain assessment (scores range from 0 to 42), and the Falls Efficacy Scale International (FES-I) for fear of falling assessment (scores range from 16 to 64). The data was analyzed using multiple linear regression. Forty-five percent of the participants had chronic pain (≥3 months) and 18% had acute pain (<3 months). Pain scores were 29±31. Pain was associated with an increase of 3 to 7 points (out of 64 max) in the FES-I. The prevalence of pain in long-term care residents was high, and pain was associated with increased fear of falling.

How many balance task trials are needed to accurately assess postural control measures in older women?

Taking the average of different trials is recommended for better balance assessment, but few studies have really proven this point under different balance conditions.

OBJECTIVE

To assess the effects of averaging trials of five different balance tasks on postural control measures in older women.

METHODS

A total of 90 older women (means: Age: 68 years; Weight: 67 kg; Height: 1.56 m; Body mass index, 27 kg/m²) participated in this study. The participants completed five balance tasks with three performance trials for each task on a force platform in random order. The participants completed a total of three 30-s trials of tasks with 30 s of rest between trials. Repeated measure ANOVA and coefficient of variation were computed to compare differences for one trial vs. averaging across two or three trials on center of pressure (COP) sway values.

RESULTS

There were no significant differences (P > 0.05) in COP sway values when comparing one vs. the average of two or three trials for all balance tasks. However, the coefficient of variation was higher for three trials (10-40%) than two (6-37%) or one trial (3-23%) for COP parameters.

CONCLUSIONS

Based on reduction of variability, the present study recommends the averaging of a minimum of two trials for balance assessment in older women. The results of the current study have implications for balance assessment in older people in fall prevention programs.

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.

Age- and low back pain-related differences in trunk muscle activation during one-legged stance balance task

BACKGROUND

Postural control declines with age and can be affected by low back pain. Poor balance has been reported in people with chronic low back pain (CLBP), which in turn could be explained by the changes in trunk muscle activation.

RESEARCH QUESTION

Are there differences between younger and older adults with and without chronic low back pain (CLBP) on trunk muscle activity during one-legged stance task?

METHODS

Twenty (20) with, and 20 subjects without nonspecific CLBP participated in the study. Each group was comprised of 10 younger (50% males; mean age: 31 years) and 10 older adults (50% males; mean age: 71 years). Subjects performed 3 × 30-second trials of one-legged stance, with eyes open, on a force platform, while surface electromyography (EMG) measurements were obtained bilaterally on the multifidus at L5, iliocostalis lumborum at L3, rectus abdominis and biceps femoris muscles.EMG amplitude analysis was processed by the Root Mean Square (250 ms window epochs) and normalized by the peak of activation during the balance tasks, to determine the muscular activity of each muscle.

RESULTS

Participants with CLBP presented 15% lower lumbar muscle activation (p <  0.05), and 23% higher co-activation (ratio between rectus adominis by multifidus) than participants without CLBP, regardless of age. Significant differences (p <  0.05) between older and young groups were observed only for lower lumbar muscles (mean 24% lower in older than younger adults) and rectus adominis muscles (mean 17% lower in older than younger adults).

SIGNIFICANCE

CLBP individuals have different trunk muscle activity than those without CLBP, and older adults exhibit lower trunk activation during one-legged stance balance task. The use of the EMG in evaluation of trunk neuromuscular function during one-legged stance may thus be a valuable tool when assessing balance in CLBP and older people.

Adult individuals with congenital, untreated, severe isolated growth hormone deficiency have satisfactory muscular function

PURPOSE

While growth hormone (GH) and the insulin-like growth factor type I (IGF-I) are known to exert synergistic actions on muscle anabolism, the consequences of prolonged GH deficiency (GHD) on muscle function have not been well defined. We have previously described a large cohort of subjects with isolated GHD (IGHD) caused by a mutation in the GH-releasing hormone receptor gene, with low serum levels of GH and IGF-I. The aim of this study was to assess muscular function in these IGHD subjects.

METHODS

A total of 31 GH-naïve IGHD (16 males) and 40 control (20 males) subjects, matched by age and degree of daily physical activity, were enrolled. Fat free mass was measured by bioelectrical impedance; muscle strength by dynamometry of handgrip, trunk extension, and knee extension; myoelectric activity and muscle fatigue by fractal dimension; conduction velocity in vastus medialis, rectus femoris, and vastus lateralis muscles by surface electromyography.

RESULTS

The IGHD group showed higher knee extension strength both when corrected for weight and fat free mass, and higher handgrip and trunk extension strength corrected by fat free mass. They also exhibit higher conduction velocity of the muscles vastus medialis, rectus femoris, and vastus lateralis, but lower free fat mass and myoelectric activity of the vastus medialis, rectus femoris and vastus lateralis. There were no differences between the two groups in fractal dimension in all studied muscles.

CONCLUSION

Individuals with untreated IGHD have better muscle strength parameters adjusted for weight and fat free mass than controls. They also exhibit greater peripheral resistance to fatigue, demonstrating satisfactory muscle function.

Osteoporosis, Activities of Daily Living Skills, Quality of Life, and Dietary Adequacy of Congregate Meal Participants

Osteoporosis, a chronic disease that results in low bone mass with an increased risk of fragility fractures, is prevalent in older adults. Diet can prevent or lessen the severity of osteoporosis. The purpose of this cross-sectional study was to assess differences in diet, quality of life, self-rated health, and physical function between congregate meal participants with and without osteoporosis. Data were from telephone survey, 10th Annual National Survey of Older American Act Participants, a representative sample of congregate meal attendees across the United States. (N = 888). Osteoporosis was present in 20% of this population. Participants with, as compared to without, osteoporosis reported that their physical health limited moderate activities (31.5% vs. 18.9%, p = 0.026), stair climbing (32.2% vs. 22.8%, p = 0.032), and shopping (27.4 vs. 15.3, p = 0.018). More than half of the participants consumed less than the recommended servings of dairy, meat, grains, and fruits/vegetables regardless of osteoporosis status. Participants with osteoporosis had lower self-rated health and more physical limitations than people without osteoporosis. Although congregate meals are a way to improve nutritional intake, additional methods to improve nutrition (including education) may be of benefit, since undernutrition is a concern in this population.

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

The purpose of this study was to evaluate the impact of body mass index (BMI) and fat mass on balance force platform measurements in older adults. The sample consisted of 257 participants who were stratified into four groups by BMI: low weight, normal weight, pre-obesity and obesity. For fat mass variables, older individuals were classified into low and high-fat mass. All groups investigated performed three trials of one-legged stance balance on a force platform. Center of pressure (COP) domain parameters were computed from the mean across trials. Analysis of variance results revealed no significant interactions for groups and sexes for all COP parameters. Comparable balance results were found for BMI and fat groups for all COP parameters. A statistical effect (P < 0.05) was only reported for sex differences for COP parameters, regardless of BMI and fat mass variables. Overall, women presented better balance than men. In conclusion, BMI and fat mass do not seem to influence the balance of older adults during a one-leg stance task.

Staphylococcus aureus Colonization and Long-Term Risk for Death, United States

To examine the association of colonization by Staphylococcus aureus and general population mortality, we followed 10,598 adults for 8.5 years on average. Methicillin-susceptible S. aureus colonization was not associated with death. Methicillin-resistant S. aureus carriage predicted death in a crude analysis but not after adjustment for socioeconomic status and co-morbidities.

Various Types of Arthritis in the United States: Prevalence and Age-Related Trends From 1999 to 2014

OBJECTIVES

To determine the prevalence trends of osteoarthritis (OA), rheumatoid arthritis (RA), and other types of arthritis in the United States from 1999 to 2014.

METHODS

We analyzed data on 43 706 community-dwelling adults aged 20 years and older who participated in the 1999-2014 National Health and Nutrition Examination Surveys. We accounted for survey design and sampling weights so that estimates were nationally representative. We assessed temporal trends in age-standardized arthritis prevalence by using joinpoint regression.

RESULTS

Age-adjusted prevalence of arthritis was 24.7% (OA = 9.7%; RA = 4.2%; other arthritis = 2.8%; "don't know" type = 8.0%). Prevalence of OA increased from 6.6% to 14.3%, whereas RA prevalence decreased from 5.9% to 3.8%. Increase in OA prevalence was significant in both genders; in non-Hispanic Whites, non-Hispanic Blacks, and Hispanics; and in people with high socioeconomic status. Decrease in RA prevalence was more pronounced in men, non-Hispanic Blacks, and participants with low income or obesity.

CONCLUSIONS

Between 1999 and 2014, nearly one quarter of American adults reported arthritis. The prevalence of OA has more than doubled over time, whereas RA prevalence has declined.

Activity of Lower Limb Muscles During Squat With and Without Abdominal Drawing-in and Pilates Breathing

Barbosa, AC, Martins, FM, Silva, AF, Coelho, AC, Intelangelo, L, and Vieira, ER. Activity of lower limb muscles during squat with and without abdominal drawing-in and Pilates breathing. J Strength Cond Res 31(11): 3018-3023, 2017-The purpose of this study was to assess the effects of abdominal drawing-in and Pilates breathing on the activity of lower limb muscles during squats. Adults (n = 13, 22 ± 3 years old) with some Pilates experience performed three 60° squats under each of the following conditions in a random order: (I) normal breathing, (II) drawing-in maneuver with normal breathing, and (III) drawing-in maneuver with Pilates breathing. Peak-normalized surface electromyography of the rectus femoris, biceps femoris, gastrocnemius medialis, and tibialis anterior during the knee flexion and extension phases of squat exercises was analyzed. There were significant differences among the conditions during the knee flexion phase for the rectus femoris (p = 0.001), biceps femoris (p = 0.038), and tibialis anterior (p = 0.001), with increasing activation from conditions I to III. For the gastrocnemius medialis, there were significant differences among the conditions during the knee extension phase (p = 0.023), with increased activity under condition I. The rectus and biceps femoris activity was higher during the extension vs. flexion phase under conditions I and II. The tibialis anterior activity was higher during the flexion compared with the extension phase under all conditions, and the medial gastrocnemius activity was higher during the extension phase under condition I. Doing squats with abdominal drawing-in and Pilates breathing resulted in increased rectus, biceps femoris, and tibialis anterior activity during the flexion phase, increasing movement stability during squat exercises.

Health Indicators of US Older Adults Who Received or Did Not Receive Meals Funded by the Older Americans Act

BACKGROUND

The Older Americans Act (OAA) requires that nutrition programs provide meals and related nutrition services that promote health and help manage chronic diseases. The purpose of this study was to compare health status, food security, functional limitations, and chronic diseases of older adults who received or did not receive OAA meals using data from a representative sample of US adults.

METHODS

Data were from the National Health and Nutrition Surveys 2011-2014 for 2,392 older adults ≥ 65 years of age, including 187 Mexican Americans, 212 other Hispanics, 521 non-Hispanic Blacks, 219 non-Hispanic Asians, and 1253 non-Hispanic Whites.

RESULTS

Those receiving OAA meals had higher percent of food insecurity and functional disabilities. Adjusting for potential confounders, adults who received OAA meals had higher odds of emphysema (OR = 2.02; 1.05, 3.89) and lower odds of good-to-excellent health (OR = 0.52; 0.36, 0.77). Women and minorities had poorer health status compared to non-Hispanic Whites.

CONCLUSION

A higher proportion of older adults who received nutritional services reported poorer health as compared to older adults who do not participate in these services. Future studies should assess nutritional adequacy for older adults who participate in nutritional programs comparing sex and race/ethnicity.

Health-Related Characteristics of Older Adults Who Attend Congregate Meal Sites in the United States

The purpose of this study was to determine health-related characteristics of a representative sample of older adults who attend congregate meal sites in the United States, and compare races/ethnicities and sexes. Participants were adults, aged 60 years and older, (N = 901) of the 2015 Tenth Annual National Survey of Older American Act Participants (NSOAAP). Difficulties with mobility and Activities of Daily Living were common among older adults who attended congregate meals. Health-related characteristics differed by race/ethnicity and sex. Higher percentages of men reported eating more than half their calories from the site: 61.0% (53, 68), compared to women: 41.2% (33,50); while twice the number of women reported exercising at the site: 42.7% (36, 50), compared to 21.8% (16, 29) for men. Hispanics reported poor/fair health, food insecurity, diabetes, and poverty more often than White non-Hispanics. The odds of reporting that meals helped maintain independence were higher for persons with food insecurity: OR = 2.67 (1.05, 6.80) and those who reported eating half or more of their calories from the site: OR = 5.78 (2.36, 14.30). Strategies that consider preferences by sex and race/ethnicity are required at congregate meal sites to encourage mobility and healthy eating.

People with chronic low back pain have poorer balance than controls in challenging tasks

PURPOSE

To compare the balance of individuals with and without chronic low back pain during five tasks.

METHOD

The participants were 20 volunteers, 10 with and 10 without nonspecific chronic low back pain, mean age 34 years, 50% females. The participants completed the following balance tasks on a force platform in random order: (1) two-legged stance with eyes open, (2) two-legged stance with eyes closed, (3) semi-tandem with eyes open, (4) semi-tandem with eyes closed and (5) one-legged stance with eyes open. The participants completed three 60-s trials of tasks 1-4, and three 30-s trials of task 5 with 30-s rests between trials. The center of pressure area, velocity and frequency in the antero-posterior and medio-lateral directions were computed during each task, and compared between groups and tasks.

RESULTS

Participants with chronic low back pain presented significantly larger center of pressure area and higher velocity than the healthy controls (p < 0.001). There were significant differences among tasks for all center of pressure variables (p < 0.001). Semi-tandem (tasks 3 and 4) and one-leg stance (task 5) were more sensitive to identify balance impairments in the chronic low back pain group than two-legged stance tasks 1 and 2 (effect size >1.37 vs. effect size <0.64). There were no significant interactions between groups and tasks.

CONCLUSIONS

Individuals with chronic low back pain presented poorer postural control using center of pressure measurements than the healthy controls, mainly during more challenging balance tasks such as semi-tandem and one-legged stance conditions. Implications for Rehabilitation People with chronic low back had poorer balance than those without it. Balance tasks need to be sensitive to capture impairments. Balance assessments during semi-tandem and one-legged stance were the most sensitive tasks to determine postural control deficit in people with chronic low back. Balance assessment should be included during rehabilitation programs for individuals with chronic low back pain for better clinical decision making related to balance re-training as necessary.

Work-related musculoskeletal disorders among physical therapists: A systematic review

Physical therapists (PTs) perform demanding tasks that can lead to work-related musculoskeletal disorders (WMSD), but the rates and characteristics of WMSD among PTs are not well known. The objective of this systematic review of the literature was to integrate the information published on the prevalence, types, and risks for WMSD among PTs. Four databases were searched using combinations and synonyms for WMSD, discomfort, symptoms, and PTs. Two reviewers independently searched and screened peer-reviewed articles published in English evaluating WMSD in PTs; agreement between reviewers was evaluated. From 867 unduplicated articles, 32 were eligible and included. Up to 90% of PTs have WMSD during their careers; 50% experience WMSD within 5 years of practice. Low back was the body part most commonly affected. Female PTs and PTs working in hospitals have higher prevalence of WMSD. WMSD are associated with PTs' age, gender, specialty and job tasks. Performing manual therapy, lifting and transferring patients are tasks commonly associated with PTs' developing WMSD. The body parts affected differed by specialty and tasks. The findings presented in this review are useful to inform future research, quality improvement, and educational programs to reduce the rates of WMSD among PTs.

Body Composition, Strength, and Dietary Intake of Patients with Hip or Knee Osteoarthritis

PURPOSE

To describe body composition (fat mass (FM) and fat-free mass (FFM)), strength, and nutritional characteristics of patients with hip or knee osteoarthritis undergoing total joint arthroplasty.

METHODS

In this prospective pilot study, osteoarthritic patients underwent body composition assessment using bioelectrical impedance analysis, grip strength measurement, and completed a 24-h dietary recall during their pre-operative assessment.

RESULTS

Fifty-five patients were included (∼66% females, age 43-89 years). Mean ± SD body mass index (BMI) was 32.79 ± 6.48 kg/m(2) and 62% were obese. Compared with hip osteoarthritis patients, knee osteoarthritis patients had a higher BMI (P = 0.018) and males with knee osteoarthritis had a lower grip strength (P = 0.028). There was a wide range in FM and FFM values across the BMI spectrum. Patients with a higher FM index (FMI, FM/height in m(2)) had higher levels of pain (P = 0.036) and females with higher FMI had a lower grip strength (P = 0.048). Dietary under-reporting was common and many patients did not meet recommendations for protein, vitamins C and E, or omega-3 fatty acids. Those who consumed less protein than the recommended dietary allowance were older (P = 0.018).

CONCLUSIONS

A wide variability of body composition and dietary intake was observed which may impact strength and ultimately affect physical function. As such, patients with osteoarthritis may benefit from targeted nutrition and physical activity interventions before and after surgery.

Falls, physical limitations, confusion and memory problems in people with type II diabetes, undiagnosed diabetes and prediabetes, and the influence of vitamins A, D and E

AIMS

To examine the association between type II diabetes, prediabetes and undiagnosed diabetes with falls, physical limitations, confusion and memory problems, and to evaluate the effects of vitamins A, D and E levels on the associations.

METHODS

Data from 37,973 participants of the National Health and Nutrition Examination Survey was analyzed.

RESULTS

The participants' mean age was 46±17years, 20% had diabetes of which 17% were unaware of their condition (undiagnosed diabetes), and 21% had prediabetes. Diabetes was significantly associated with falls, difficulties in stooping, crouching, kneeling, completing house chores, getting in and out bed, standing and sitting for long periods, reaching over head, grasping, holding objects, and attending social events. The association between diabetes and confusion or memory problems was stronger for those diagnosed before age 40. Memory problems were reported only by people with diabetes with lower vitamin D levels. Vitamin A and E levels did not modify the association between diabetes and falls or any of the physical functions, confusion or memory problems. Prediabetes was only associated with difficulty standing for long periods.

CONCLUSIONS

Diabetes was associated with falls, difficulties in physical functioning and attending social events. Vitamin D levels modified the effects on confusion and memory problems.

Work-related musculoskeletal disorders among physical therapists: an online survey

PURPOSE

To evaluate the rates and characteristics of musculoskeletal disorders (MSDs) in physical therapists (PTs) according to their specialty and setting.

METHOD

Participants completed an online questionnaire including 15 demographic questions, 7 work-related and 8 injury-related questions for 9 different body parts.

RESULTS

Complete responses were obtained from 121 PTs; 96% reported MSD symptoms during the previous 12 months, 64% affecting at least 3 body parts. The body parts with the highest prevalence of symptoms were the low back (66%) and the neck (61%). For PTs specialized in acute care, geriatrics and pediatrics, the body part most commonly affected was the low back, while for PTs specialized in orthopedics and neurology, the body part most commonly affected was the neck. Regarding work settings, the low back was the most commonly affected for PTs working in skilled nursing facilities, outpatient clinics and hospitals, and the neck in PTs working in academic and home health settings.

CONCLUSIONS

MSDs are common among PTs; the body parts most often affected were the low back and neck. The prevalence and body parts affected varied by practice setting and specialty area. The findings can help informing the design of evidence-based rehabilitation, prevention, training and educational programs.

IMPLICATIONS FOR REHABILITATION

Rehabilitation of injured physical therapists needs to address the symptoms of the multiple body parts that are usually affected (e.g. back, wrists and hands). Rehabilitation of injured physical therapists needs to take into consideration their job demands, practice setting and specialty area. The findings can inform the design of rehabilitation, prevention, training and educational programs for physical therapists.

Does wearing unstable shoes reduce low back pain and disability in nurses? A randomized controlled pilot study

OBJECTIVE

To evaluate if wearing unstable shoes reduces low back pain and disability in nurses.

DESIGN

A randomized controlled trial.

SETTING

Hospitals and homecare.

SUBJECTS

A total of 20 matched female registered nurses with low back pain. The mean (standard deviation) age was 31 years (5) for the control and 34 years (6) for the intervention group; height was 161 cm (5) and 165 cm (7), respectively.

INTERVENTIONS

The intervention group received unstable shoes at Week 2 to wear for at least 36 h/week for a month.

MAIN MEASURES

The Oswestry Low Back Pain Disability Questionnaire and a visual analogue pain scale.

RESULTS

The mean (standard deviation) pain level was 6 (1) at baseline vs. 6 (2) at Week 6 for the control group, and 5 (1) vs. 1 (1) for the intervention group. The mean (standard deviation) disability level was 31% (9) at baseline vs. 28% (7) at Week 6 for the control, and 27% (12) vs. 13% (5) for the intervention group. There were no significant changes over time on pain or disability levels for the control group. The intervention group reported lower levels of pain on Weeks 4 (mean difference ⩾-1.4, p ⩽ 0.009) and 6 (mean difference ⩾-3.1, p < 0.001). Disability levels were also lower on Weeks 4 (mean difference = -4.5%, p NS) and 6 (mean difference = -14.1%, p = 0.020).

CONCLUSIONS

Wearing unstable shoes reduced low back pain and disability in nurses and might be helpful as part of the back pain rehabilitation process.

Kinesio Taping effects on knee extension force among soccer players

Background:

Kinesio Taping (KT) is widely used, however the effects of KT on muscle activation and force are contradictory.

Objective:

To evaluate the effects of KT on knee extension force in soccer players.

Method:

This is a clinical trial study design. Thirty-four subjects performed two maximal isometric voluntary contractions of the lower limbs pre, immediately post, and 24 hours after tape application on the lower limbs. Both lower limbs were taped, using K-Tape and 3M Micropore tape randomly on the right and left thighs of the participants. Isometric knee extension force was measured for dominant side using a strain gauge. The following variables were assessed: peak force, time to peak force, rate of force development until peak force, time to peak rate of force development, and 200 ms pulse.

Results:

There were no statistically significant differences in the variables assessed between KT and Micropore conditions (F=0.645, p=0.666) or among testing sessions (pre, post, and 24h after) (F=0.528, p=0.868), and there was no statistical significance (F=0.271, p=0.986) for interaction between tape conditions and testing session.

Conclusion:

KT did not affect the force-related measures assessed immediately and 24 hours after the KT application compared with Micropore application, during maximal isometric voluntary knee extension.

Immediate rather than delayed memory impairment in older adults with latent toxoplasmosis

The neurotropic parasite Toxoplasma gondii infects one third of the world population, but its effect on memory remains ambiguous. To examine a potential relationship of the infection with immediate and delayed memory, a population-based study was conducted in 4485 participants of the Third National Health and Nutrition Examination Survey aged 60years and older. Serum anti-Toxoplasma IgG antibodies were measured by enzyme immune assay and verbal memory was assessed using the Mini-Mental State Examination and the East Boston Memory Test. The prevalence of latent toxoplasmosis was 41%; in one way analysis of variance, anti-Toxoplasma IgG antibody levels significantly differed across tertiles for immediate (P=0.006) but not delayed memory scores (P=0.22). In multinomial logistic regression adjusting for covariates, Toxoplasma seropositivity was associated with lower immediate memory performance (OR: 0.65, 95% CI: 0.44, 0.97 for medium tertile and OR: 0.61, 95% CI: 0.37, 0.98 for highest tertile in reference to the lowest tertile), especially in non-Hispanic Whites (OR: 0.56, 95% CI: 0.36, 0.88 for medium tertile and OR: 0.51, 95% CI: 0.30, 0.87 for highest tertile in reference to the lowest tertile). However, no relationship with delayed memory was observed. In conclusion, latent toxoplasmosis is widespread in older adults and may primarily affect immediate rather than delayed memory, particularly in White Americans.

Temporo-spatial gait parameters during street crossing conditions: a comparison between younger and older adults

Most traffic accidents involving pedestrians happen during street crossing. Safe street crossing by older adults requires complex planning and imposes high cognitive demands. Understanding how street crossing situations affect younger and older adults' gait is important to create evidence-based policies, education and training. The objective of this study was to develop and test a method to evaluate temporo-spatial gait parameters of younger and older adults during simulated street crossing situations. Twenty-two younger (25±2 years old) and 22 older adults (73±6 years old) who lived independently in the community completed 3 walking trials at preferred gait speed and during simulated street crossing with regular and with reduced time. There were significant differences between groups (p<0.001) and conditions (p<0.001). Older adults' street crossing walking speed was higher than their preferred speed (p<0.001). Gait during simulated street crossing resulted in significant and progressive gait changes. The methods developed and tested can be used to (1) evaluate if people are at risk of falls and accidents during street crossing situations, (2) to compare among different groups, and (3) to help establish appropriate times for older pedestrians to cross streets safely. The current time to cross streets is too short even for healthy older adults.

Prospective study of cytomegalovirus seropositivity and risk of mortality from diabetes

Cytomegalovirus (CMV) infects 40 % of the world population and has been suggested to be associated with diabetes; however, no prospective study has ever examined diabetes mortality associated with the infection. A cohort of 14,404 non-diabetic adult participants aged 17-90 years from the Third National Health and Nutrition Examination Survey (1988-1994) was prospectively followed for mortality through 2006. CMV immunoglobulin G was measured by enzyme-linked immunosorbent assay and immunofluorescence assay. Diabetes death was assessed with death records from the National Death Index. Cox proportional hazards modeling was used to determine diabetes mortality risk associated with CMV infection, adjusting for socio-demographics, diabetes risk factors, and comorbidities. At baseline, 76.8 % of subjects were CMV seropositive, and after an average follow-up of 13.7 years, diabetes mortality rate per 10,000 person-years was 6.8 (95 % CI 5.7, 8.0). Among seropositive participants, the diabetes death rate (8.4, 95 % CI 7.0, 9.9) was more than four times the rate in seronegative ones (2.0, 95 % CI 1.1, 3.6) (P value for the difference <0.001). In the adjusted Cox proportional hazards analysis, CMV seropositivity more than doubled the risk of diabetes mortality (HR 2.06, 95 % CI 1.05, 4.06). CMV infection may thus predict future mortality from diabetes in non-diabetic people.

Probiotic administration in early life, atopy, and asthma: a meta-analysis of clinical trials

BACKGROUND AND OBJECTIVE

Probiotics may reduce the risk of atopy and asthma in children. However, results from clinical trials have been conflicting, and several of them may have been underpowered. We performed a meta-analysis of randomized, placebo-controlled trials to assess the effects of probiotic supplementation on atopic sensitization and asthma/wheeze prevention in children.

METHODS

Random-effects models were used to calculate pooled risk estimates. Meta-regression was conducted to examine the effect of potential factors on probiotics efficacy.

RESULTS

Probiotics were effective in reducing total immunoglobulin E (IgE) (mean reduction: -7.59 U/mL [95% confidence interval (CI): -14.96 to -0.22]; P = .044). Meta-regression showed that the reduction in IgE was more pronounced with longer follow-up. Probiotics significantly reduced the risk of atopic sensitization when administered prenatally (relative risk: 0.88 [95% CI: 0.78 to 0.99]; P = .035 for positive result on the skin prick test and/or elevated specific IgE to common allergens) and postnatally (relative risk: 0.86 [95% CI: 0.75 to 0.98]; P = .027 for positive result on skin prick test). Administration of Lactobacillus acidophilus, compared with other strains, was associated with an increased risk of atopic sensitization (P = .002). Probiotics did not significantly reduce asthma/wheeze (relative risk: 0.96 [95% CI: 0.85 to 1.07]).

CONCLUSIONS

Prenatal and/or early-life probiotic administration reduces the risk of atopic sensitization and decreases the total IgE level in children but may not reduce the risk of asthma/wheeze. Follow-up duration and strain significantly modified these effects. Future trials for asthma prevention should carefully select probiotic strain and consider longer follow-up.

Work disability benefits due to musculoskeletal disorders among Brazilian private sector workers

OBJECTIVE

To evaluate the prevalence and characteristics of disability benefits due to musculoskeletal disorders (MSD) granted to Brazilian private sector workers.

METHODS

This was a population-based epidemiological study of MSD-related benefits among registered private sector workers (n=32 959 329). The prevalence (benefits/10 000 workers/year) of work disability benefits was calculated by gender, age, state, Human Development Index (HDI), economic activity, MSD type and work-relatedness.

RESULTS

The prevalence of MSD-related benefits in Brazil among registered private sector workers in 2008 was 93.6/10 000 workers. The prevalence increased with age, and was higher for women (112.2) than for men (88.1), although the former had shorter benefit duration. The gender-adjusted prevalence by state varied from 16.6 to 90.3 for non-work-related, and from 7.8 to 59.6 for work-related benefits. The Brazilian states with a high-very high HDI had the highest prevalence. The top four most common types of MSD-related benefits were due to back pain, intervertebral disc disorders, sinovitis/tenosynovitis and shoulder disorders.

CONCLUSION

MSD is a frequent cause of work disability in Brazil. There were differences in prevalence among economic activities and between states grouped by HDI. This study demonstrates that further evaluation of the contributing factors associated with MSD-related disability benefits is required. Factors that should be considered include production processes, political organisation, socioeconomic and educational characteristics, the compensation and recording systems, and employee-employer power relationships. These factors may play an important role in the prevalence of MSD-related disability benefits, especially in countries with large socioeconomic iniquities such as Brazil.

Cervical muscle response to trunk flexion in whiplash-type lateral impacts

The purpose of this study was to determine the response of the cervical muscles to increasing low-velocity, whiplash-type lateral impacts when the occupant is seated out of the recommended driving position (neutral posture). Twenty healthy volunteers were subjected to left lateral impacts of 4.1, 7.7, 10.5, and 13.7 m/s(2) acceleration, with their trunk flexed by 45 degrees and laterally flexed to the right and left also by 45 degrees at the time of impact. Bilateral electromyograms of the sternocleidomastoids, trapezii, and splenii capitis were recorded. Under these conditions of trunk-flexed postures, in a left lateral impact, muscle responses were of generally low magnitude with the trunk flexed to either the left or right. Even at the highest acceleration of 13.7 m/s(2), all muscles generated less than 37% of their known maximal voluntary contraction electromyogram. Also, in these left lateral impacts, the right splenius capitis showed a greater EMG response than the left splenius capitis regardless of whether the subject was flexed to the right or left at the time of impact. The right splenius capitis (the one contralateral to the left lateral impact direction) was more active than its counterpart. Compared to what is known for EMG responses with an occupant in the neutral posture, the right sternocleidomastoid (usually the most active muscle in a left lateral collision) was significantly less-active with trunk flexion than with neutral posture conditions (P<0.01). In the absence of bodily impact, the flexed trunk posture does not produce a biomechanical response that would increase the likelihood of cervical muscle injury in low velocity lateral impacts, and may lessen the risk of injury for some muscles.

Effect of Trunk Flexion on the Occupant Neck Response to Anterolateral Whiplash Impacts

OBJECTIVE

The purpose of this study was to determine the response of the cervical muscles to increasing low-velocity anterolateral impacts with the volunteer's trunk flexed to the right and left.

METHODS

A total of 20 healthy volunteers were subjected to left anterolateral impacts of 4.0, 7.6, 10.7, and 13.4 m/sec and, sequentially, with trunk flexed either left or right. Bilateral electromyograms (EMGs) of the sternocleidomastoids, trapezii, and splenii capitis were recorded.

DESIGN

At an acceleration of 13.4 m/sec, with the trunk flexed left, the left trapezius generated 48% of its maximal voluntary contraction EMG, whereas the right trapezius (contralateral to the left anterolateral impact) generated 38% of this variable. All other muscle generated </=23% of their maximal voluntary contraction EMG, a significant difference from the trapezii (P = 0.005). Similarly, with the trunk flexed to the right under these same conditions, the left trapezius generated 26% and the right trapezius 35% of their maximal voluntary contraction EMG. Again, all other muscles generated significantly less EMG activity, </=22% (P = 0.009). Overall, the EMG responses were of low magnitude compared with known data with the trunk in neutral posture in this direction of impact.

CONCLUSIONS

When the subject sits with trunk flexed out of neutral posture at the time of an anterolateral impact, the cervical muscle response is reduced compared with anterolateral impacts with the trunk in neutral posture.