Muscle Performance as a Predictor of Bone Health: Among Community-Dwelling Postmenopausal Japanese Women from Setagaya-Aoba Study.

Osteoporosis is a significant health concern for postmenopausal women, necessitating efficient screening methods for bone health. This study explores the potential of muscle function, assessed through the 30-s chair stand test (CS-30), as an indicator for low bone stiffness in this demographic, aiming to establish a practical threshold for large-scale fitness surveillance without the need for specialized tools. We analyzed data from 1055 community-dwelling postmenopausal Japanese women, aged 41-89 years, collected between 2016 and 2019. Participants underwent CS-30 to evaluate muscle function alongside quantitative ultrasound (QUS) measurements to assess bone stiffness. The cohort was divided into two groups for the development and validation of a cutoff point for low bone stiffness, defined as a QUS speed of sound less than 1487.3 m/s. The CS-30 cutoff was determined using receiver operating characteristic (ROC) curve analysis and validated through logistic regression, accounting for age, body mass index, and smoking status. Among 577 postmenopausal women, 16.0% exhibited low bone stiffness. In the development group (n = 382), ROC analysis identified a CS-30 cutoff of 25 repetitions for detecting low bone stiffness, with an area under the curve of 0.744 (P < 0.001). In the validation group (n = 195), participants performing ≥ 25 repetitions had a higher risk of low bone stiffness compared to those performing ≤ 24 repetitions. The CS-30 test is an effective preliminary screening tool for identifying postmenopausal women at risk of low bone stiffness, with a threshold of 25 repetitions. This method could facilitate early detection of individuals at higher osteoporosis risk, promoting timely intervention.

Sarcopenia prevalence using handgrip strength or chair stand performance in adults living with type 2 diabetes mellitus.

BACKGROUND: The updated European Working Group on Sarcopenia in Older People (EWGSOP2) recommends handgrip strength (HGS) and the chair stand test (CST) to assess muscle strength, with the CST being a convenient proxy for lower limb strength. However, adiposity may differentially influence these strength criteria and produce discrepant sarcopenia prevalence. OBJECTIVE: To determine the prevalence of sarcopenia using HGS or the CST, and to investigate the associations between these strength criteria and adiposity in adults with type 2 diabetes mellitus. METHODS: The EWGSOP2 definition was used to assess the prevalence of probable (low muscle strength), confirmed (plus low muscle mass) and severe (plus poor physical performance) sarcopenia. Linear regression models were used to study the association between different measures of muscle strength and adiposity. RESULTS: We used data from 732 adults with type 2 diabetes mellitus (35.7% female, aged 64 ± 8 years, body mass index 30.7 ± 5.0 kg/m2). Using the CST compared with HGS produced a higher prevalence of probable (31.7% vs. 7.1%), confirmed (5.6% vs. 1.6%) and severe (1.0% vs. 0.3%) sarcopenia, with poor agreement between strength criteria to identify probable sarcopenia. CST performance, but not HGS, was significantly associated with all measures of adiposity in unadjusted and adjusted models. CONCLUSIONS: Higher levels of adiposity may impact CST performance, but not HGS, resulting in a higher prevalence of sarcopenia in adults with type 2 diabetes mellitus. Consideration should be paid to the most appropriate measure of muscle function in this population.

Sarcopenia and its effects on outcome of lumbar spine surgeries.

PURPOSE: Sarcopenia, defined as progressive impairment of muscle function secondary to loss of skeletal muscle mass, has prevalence of 24-56% in patients > 60 years. Forty-four per cent of elderly patients undergoing orthopaedic surgery are found to be sarcopenic. It is a known risk factor for fall, fractures, disability, increased post-operative morbidity and mortality. If diagnosed pre-operatively, it can help prepare the patient and surgical team to foresee complications and thereby reduce morbidity and mortality. In the present study, we evaluated and correlated sarcopenia with the surgical outcome of operated patients with lumbar spine pathology. MATERIALS AND METHODS: A prospective, observational study was conducted on 114 patients > 40 years undergoing lumbar spine surgeries, who were studied and followed up for 3 months. They were segregated into 5 groups based on age (40-50 year, 50-60 year, 60-70 year, 70-80 year, and > 80 year) and were assessed separately. Data on demography, grip strength analysis, 30-s chair stand test, Psoas muscle index (calculated on pre-operative MRI), pre- and post-operative ODI (Oswestry Disability Index) scores at 2 weeks and 3 months, Dindo-Clavien Classification of peri-operative complications, 90-day readmission rates and mortality (if any) were included. Patients were segregated into sarcopenic and non-sarcopenic groups based on the definition and set parameters as per the European Working Group on Sarcopenia in Older People (EWGSOP). A comparative analysis between these groups was performed. RESULTS: Of 114 patients, there were 18 patients in 40-49 years, 24 in 50-59 years, 33 in 60-69 years, 30 in 70-79 years and 9 in > 80 years age group. Statistically significant difference in peri-operative ODI scores was seen in sarcopenic vs non-sarcopenic patients in all age groups (p < 0.05) except 40-49 years. The results showed that sarcopenic group had higher rate of peri-operative complications, delayed mobilisation, longer stay and mortality compared to non-sarcopenic group. CONCLUSION: We conclude that sarcopenic patients have poor outcome in lumbar spine surgery compared to those without. So, by diagnosing sarcopenia using tests routinely done as pre-operative requirement, one can reduce radiation exposure and cost of treatment. The management can be revolutionised by predicting those who are at high risk of developing post-operative complications and poor surgical outcomes by mere diagnosis of sarcopenia. This knowledge will benefit both the patients and the surgeons.

Sensor-Integrated Chairs for Lower Body Strength and Endurance Assessment.

This paper describes an automated method and device to conduct the Chair Stand Tests of the Fullerton Functional Test Battery. The Fullerton Functional Test is a suite of physical tests designed to assess the physical fitness of older adults. The Chair Stand Tests, which include the Five Times Sit-to-Stand Test (5xSST) and the 30 Second Sit-to-Stand Test (30CST), are the standard for measuring lower-body strength in older adults. However, these tests are performed manually, which can be labor-intensive and prone to error. We developed a sensor-integrated chair that automatically captures the dynamic weight and distribution on the chair. The collected time series weight-sensor data is automatically uploaded for immediate determination of the sit-to-stand timing and counts, as well as providing a record for future comparison of lower-body strength progression. The automatic test administration can provide significant labor savings for medical personnel and deliver much more accurate data. Data from 10 patients showed good agreement between the manually collected and sensor-collected 30CST data (M = 0.5, SD = 1.58, 95% CI = 1.13). Additional data processing will be able to yield measurements of fatigue and balance and evaluate the mechanisms of failed standing attempts.

Comparing associations of handgrip strength and chair stand performance with all-cause mortality-implications for defining probable sarcopenia: the Tromsø Study 2015-2020.

BACKGROUND: Widely adopted criteria suggest using either low handgrip strength or poor chair stand performance to identify probable sarcopenia. However, there are limited direct comparisons of these measures in relation to important clinical endpoints. We aimed to compare associations between these two measures of probable sarcopenia and all-cause mortality. METHODS: Analyses included 7838 community-dwelling participants (55% women) aged 40-84 years from the seventh survey of the Tromsø Study (2015-2016), with handgrip strength assessed using a Jamar + Digital Dynamometer and a five-repetition chair stand test (5-CST) also undertaken. We generated sex-specific T-scores and categorised these as "not low", "low", and "very low" handgrip strength or 5-CST performance. Cox Proportional Hazard regression models were used to investigate associations between these two categorised performance scores and time to death (up to November 2020 ascertained from the Norwegian Cause of Death registry), adjusted for potential confounders including lifestyle factors and specific diseases. RESULTS: A total of 233 deaths occurred (median follow-up 4.7 years) with 1- and 5-year mortality rates at 3.1 (95% confidence interval [CI] 2.1, 4.6) and 6.3 (95% CI 5.5, 7.2) per 1000 person-years, respectively. There was poor agreement between the handgrip strength and 5-CST categories for men (Cohen's kappa [κ] = 0.19) or women (κ = 0.20). Fully adjusted models including handgrip strength and 5-CST performance mutually adjusted for each other, showed higher mortality rates among participants with low (hazard ratio [HR] 1.22, 95% CI 0.87, 1.71) and very low (HR 1.68, 95% CI 1.02, 2.75) handgrip strength compared with the not low category. Similar associations, although stronger, were seen for low (HR 1.88, 95% CI 1.38, 2.56) and very low (HR 2.64, 95% CI 1.73, 4.03) 5-CST performance compared with the not low category. CONCLUSIONS: We found poor agreement between T-score categories for handgrip strength and 5-CST performance and independent associations with mortality. Our findings suggest that these tests identify different people at risk when case-finding probable sarcopenia. As discussions on an international consensus for sarcopenia definitions proceed, testing both handgrip strength and chair stand performance should be recommended rather than viewing these as interchangeable assessments.

The relationship between sarcopenia-related measurements and osteoporosis: The SARCOP study.

As muscle and bone are closely-related, we have explored the association between sarcopenia-related measurements and bone mineral density (BMD) (and osteoporosis) in postmenopausal women. Grip strength, anterior thigh muscle thickness and chair stand test were found to be related with BMD. Additionally, grip strength < 22 kg increased the odds ratio of osteoporosis 1.6 times. INTRODUCTION: As muscle and bone are two closely related tissues, we aimed to investigate the association between sarcopenia-related measurements (i.e., sonographic anterior thigh muscle thickness, grip strength, chair stand test (CST), gait speed) and clinical factors, lumbar/femoral BMD, and the presence of osteoporosis (OP) in postmenopausal women. METHODS: Community dwelling postmenopausal women from two physical and rehabilitation medicine outpatient clinics were consecutively included in this cross-sectional study. Demographic data, age, weight, height, education/exercise status, smoking, and comorbidities were registered. BMD measurements were performed from lumbar vertebrae (L1-4) and femoral neck using dual energy X-ray absorptiometry (DXA). A T-score of ≤ -2.5 SD in the lumbar vertebrae (L1-L4) and/or femoral neck was accepted as OP. Anterior thigh muscle thickness (MT) at the midthigh level was measured sonographically using a linear probe. Grip strength was measured from the dominant side. Physical performance was assessed by CST and gait speed. RESULTS: Among 546 postmenopausal women, 222 (40.7%) had OP. Among sarcopenia-related parameters, grip strength and anterior thigh MT were positively associated with lumbar vertebral BMD. CST performance was positively associated with femoral neck BMD. After adjusting for confounding factors, low grip strength (< 22 kg) increased 1.6 times the risk of OP. CONCLUSION: Loss of muscle mass/function (i.e., sarcopenia) can coexist with loss of trabecular and cortical bone. To this end, grip strength and anterior thigh MT seem to be associated with the lumbar vertebral BMD, while CST is associated with the femoral neck BMD. Lastly, low grip strength might have an association with postmenopausal OP.

The Effect of Social Isolation on Sarcopenia: A Longitudinal Study among the Middle-Aged and Older Population in China.

INTRODUCTION: Although social isolation is associated with premature death and somatic and mental diseases, evidence of its long-term effect on sarcopenia is scarce. This study aimed to examine the longitudinal association between social isolation and possible sarcopenia. METHODS: We extracted baseline and 4-year follow-up data from the China Health and Retirement Longitudinal Study and included participants aged 45 years or above. Social isolation was measured by factors including living alone, marital status, frequency of contact with adult children and friends, and participation in social activity. The change in social isolation from baseline to follow-up was classified into stable, progressive, and regressive groups. Possible sarcopenia was detected using the handgrip strength and five-time chair-stand test. Using mixed-effects logistic regression, we studied the effect of baseline isolation and the change in isolation status on possible sarcopenia at a 4-year follow-up. RESULTS: A total of 5,289 participants aged 45-90 years and without possible sarcopenia at baseline were included. After 4 years, possible sarcopenia was detected in 21.7% (1,146/5,289) of the participants. Compared with the low social isolation group, the middle (OR = 1.53, 95% confidence interval [CI] = 1.16-2.04, p = 0.003) and high social isolation groups (OR = 1.65, 95% CI = 1.26-2.18, p < 0.001) were associated with a higher risk of possible sarcopenia. Being not married/cohabiting (OR = 1.58, 95% CI = 1.19-2.10, p = 0.002), lack of contact with children (OR = 1.86, 95% CI = 1.21-2.85, p = 0.004), and lack of social activities (OR = 1.26, 95% CI = 1.04-1.53, p = 0.019) were associated with an increased risk of possible sarcopenia. Compared with the stable social isolation group, the progressive group was associated with a greater risk of possible sarcopenia (OR = 1.51, 95% CI = 1.17-1.95, p = 0.001). CONCLUSIONS: Social isolation is associated with an increased risk of possible sarcopenia. Progressive social isolation further elevates the risk. The most vulnerable groups are middle-aged and older people who live alone, are not socially active, and lack contact with their children.

Clinical utility of markerless motion capture for kinematic evaluation of sit-to-stand during 30 s-CST at one year post total knee arthroplasty: a retrospective study.

BACKGROUND: Although the importance of kinematic evaluation of the sit-to-stand (STS) test of total knee arthroplasty (TKA) patients is clear, there have been no reports analyzing STS during the 30-s chair sit-up test (30 s-CST) with a focus on kinematic characteristics. This study aimed to demonstrate the clinical utility of kinematic analysis of STS during the 30 s-CST by classifying STS into subgroups based on kinematic parameters, and to determine whether differences in movement strategies are expressed as differences in clinical outcomes. METHODS: The subjects were all patients who underwent unilateral TKA due to osteoarthritis of the knee and were followed up for one year postoperatively. Forty-eight kinematic parameters were calculated using markerless motion capture by cutting STS in the 30 s-CST. The principal components of the kinematic parameters were extracted and grouped by kinematic characteristics based on the principal component scores. Clinical significance was examined by testing whether differences in patient-reported outcome measures (PROMs) were observed. RESULTS: Five principal components were extracted from the 48 kinematic parameters of STS and classified into three subgroups (SGs) according to their kinematic characteristics. It was suggested that SG2, using a kinematic strategy similar to the momentum transfer strategy shown in previous studies, performed better in PROMs and, in particular, may be associated with achieving a "forgotten joint", which is considered the ultimate goal after TKA. CONCLUSIONS: Clinical outcomes differed according to kinematic strategies used STS, suggesting that kinematic analysis of STS in 30 s-CST may be useful in clinical practice. TRIAL REGISTRATION: This study was approved by the Medical Ethical Committee of the Tokyo Women's Medical University (approval number: 5628 on May 21, 2021).

Orthostatic Blood Pressure Recovery Measured Using a Sphygmomanometer Is Not Associated with Physical Performance or Number of Falls in Geriatric Outpatients.

BACKGROUND: Orthostatic hypotension (OH) and impaired OH recovery derived from beat-to-beat blood pressure (BP) measurements are associated with detrimental clinical outcome, but the clinical relevance of OH recovery assessed using the widely available sphygmomanometer is still unclear. METHOD: 635 geriatric outpatients underwent comprehensive geriatric assessment, including orthostatic BP measurements using a sphygmomanometer, during supine rest and 1 and 3 min after standing up and assessment of physical performance (i.e., the timed up and go test and the Short Physical Performance Battery) and the number of falls in the past year. The association between BP recovery, defined as BP at 3 min minus BP at 1 min after standing up, with physical performance and falls was assessed using regression analyses, adjusting for age and sex, both in the entire cohort and after stratifying for the presence of OH at 1 min after standing up. RESULTS: BP recovery was not associated with physical performance or number of falls, neither in the entire cohort, nor in subpopulations with or without OH. CONCLUSION: The clinical relevance of BP recovery between 1 and 3 min after standing up could not be demonstrated. The results suggest that sphygmomanometer measurements have an inadequate time resolution to record the clinically relevant dynamics of orthostatic BP recovery.

Lower body muscle strength, dynapenic obesity and risk of type 2 diabetes -longitudinal results on the chair-stand test from the Survey of Health, Ageing and Retirement in Europe (SHARE).

BACKGROUND: The chair-stand test is a measure of lower body muscle strength. In a longitudinal study with older adults, we investigated whether results of the five-repetition chair-stand test (CST-5) are associated with incident type 2 diabetes, and whether diabetes risk in obese persons is modified by dynapenia (age-related loss of muscle strength) in the lower limbs. METHODS: We used data of the Survey of Health, Ageing and Retirement in Europe (SHARE), a panel study with eight waves carried out between 2004 and 2020 in 28 European countries and Israel mainly in persons aged 50 years or older. Forty-six thousand one hundred nineteen persons (mean age 63.5 years, 44.1% men) with CST-5 data and follow-up data for diabetes were included from wave 2 and waves 4 to 7. The mean follow-up time was 5.3 years (standard deviation 2.9 years). Relative risks with 95% confidence intervals (CI) were estimated from log-linear models with a Poisson working likelihood and robust standard errors. RESULTS: In the crude model, increased risks of diabetes were found for persons who considered the CST-5 as not safe, or whose times for the test were in the highest or second highest quartiles (relative risks 2.18 (95% CI: 1.95-2.43), 1.71 (1.54-1.91), 1.44 (95% CI: 1.29-1.61), reference: lowest quartile). These associations were attenuated in the fully adjusted regression model (relative risks 1.32 (95% CI: 1.17-1.48), 1.23 (1.10-1.37), 1.19 (1.06-1.33)). Furthermore, in fully adjusted models, the risk of diabetes in obese persons did not depend on whether they had low muscle strength or not. In obese persons with times for 5 sits and stands > 15 seconds, the adjusted risk of diabetes was 2.56 (95% CI: 2.22-2.95) times higher than in non-obese persons with times ≤15 seconds. The corresponding relative risk in obese persons with times ≤15 seconds was 2.45 (2.25-2.67). CONCLUSIONS: Poor results in the CST-5 were associated with an increased risk of diabetes. Among obese persons, the risk of diabetes was not modified by results of the CST-5.

Homing in on cognition with cross-sectional analysis of sarcopenia-related measurements: the SARCOG study.

BACKGROUND: Cognitive impairment may cause significant decline in muscle function and physical performance via affecting the neuromotor control. AIM: To investigate the relationship between cognition and sarcopenia-related parameters in middle-aged and older adults. METHODS: Demographic data and comorbidities of adults ≥ 45-year-old were noted. The Mini-Mental State Examination (MMSE) was used to evaluate global cognitive function. Sonographic anterior midthigh muscle thickness, handgrip strength, chair stand test (CST) and gait speed were measured. The diagnosis of sarcopenia was established if low muscle mass was combined with low muscle function. Dynapenia was defined as low grip strength or increased CST duration. RESULTS: Among 1542 subjects (477 M, 1065 F), sarcopenia and dynapenia were detected in 22.6 and 17.2% of males, and 17.2 and 25.3% of females, respectively. Sarcopenic patients were older and had higher body mass index, higher frequencies of hypertension, diabetes mellitus and obesity. They had lower muscle thickness, grip strength in males only, CST performance in females only and gait speed than the other groups (all p < 0.05). Sarcopenic and dynapenic patients had similar MMSE scores which were lower than those of normal subjects (both p < 0.001). After adjusting for confounding factors, MMSE values were positively related with grip strength in females only, CST performance and gait speed (all p < 0.001); but not with muscle thickness in either gender. CONCLUSION: Cognitive impairment may unfavorably affect muscle function and physical performance, but not muscle mass. Accordingly, its prompt management can help to decrease patient morbidity and mortality.

Chair stand test as a proxy for physical performance and muscle strength in sarcopenia diagnosis: the Korean frailty and aging cohort study.

BACKGROUND: The 5-times chair stand test (5CST) is a proxy tool for measuring physical performance and muscle strength in diagnosing sarcopenia. The Asian Working Group for Sarcopenia 2019 guidelines recommends the 5CST for evaluating gait speed, whereas the European Working Group on Sarcopenia in Older People guidelines recommend the chair stand test as a proxy for muscle strength. AIMS: This study sought to determine whether the chair stand test correlates with handgrip strength and gait speed, and investigate sex differences in these relationships. METHODS: We used data collected from 1416 participants (678 men and 738 women) in the 2017 Korean Frailty and Aging Cohort Study (KFACS). RESULTS: The 5CST time had a higher correlation with gait speed (r = - 0.470) than handgrip strength (r = - 0.309). In addition, 5CST time predicted low gait speed (area under the curve [AUC] 0.727) better than low handgrip strength (AUC 0.641). The optimal cutoff values of the 5CST to estimate low gait speed were 10 s for men (sensitivity 62%, specificity 64%) and 11 s for women (sensitivity 68%, specificity 67%). The optimal cutoff values of the 5CST for low handgrip strength were the same as those for low gait speed (10 s for men and 11 s for women). CONCLUSIONS: The 5-times chair stand test fits with gait speed and handgrip strength but seems to be a better proxy of gait speed than handgrip strength. The optimal cutoff values of the 5CST to estimate low gait speed and low handgrip strength were lower in men than women. Although none of the AWGS 2019 or EWGSOP guidelines present sex-specific cutoffs for the 5CST, it needs to be considered in the next guidelines.

Reliability of graded cycling test with talk test and 30-s chair-stand test in men with prostate cancer on androgen deprivation therapy.

PURPOSE: To investigate the absolute and relative reliability of the "graded cycling test with talk test" (GCT-TT) and the "30-second chair-stand test" (30s-CST) in men with prostate cancer receiving androgen deprivation therapy (ADT). METHODS: Men with prostate cancer on ADT were included in this test-retest study. GCT-TT and 30s-CST were performed twice with 1 hour between test sessions. All tests were conducted by two experienced physiotherapists and all patients were familiar with the tests. Only intra-tester reliability was investigated as the test and retest of each participant were performed by the same physiotherapist. Intraclass correlation coefficient (ICC2.1), standard error of measurement (SEM and SEM95), and smallest real difference (SRD) were calculated. RESULTS: Sixty men were included with a mean age of 70.8 ± 6.6 (mean ± SD) years. All performed 30s-CST twice without any problems. Two participants were excluded from the analysis of the GCT-TT results. Relative reliability for 30s-CST (ICC2.1) was 0.97 [95% CI: 0.94-0.98] with low measurement error: SEM95, 1.9 repetitions, and SRD, 2.6 repetitions. The corresponding results for GCT-TT were ICC2.1, 0.90 [95% CI: 0.84-0.94]; SEM95, 19.9 W; and SRD, 28.2 W. CONCLUSIONS: The reliability of 30s-CST and GCT-TT is substantial for men with prostate cancer receiving ADT. Overall, an average 30s-CST improvement of 1.9 repetitions on a group level and three repetitions for individual patients are considered real improvements. A GCT-TT improvement exceeding 19.9 W represents a real improvement for a group of patients. Individual patients need to improve two steps (30 W).

The 30-s chair stand test can be a useful tool for screening sarcopenia in elderly Japanese participants.

BACKGROUND: Low muscle strength has been focused on as an essential characteristic of sarcopenia, and the 30-s chair stand test (CS-30) could be a particularly useful test for assessing muscle strength. While it is speculated to be a beneficial tool for the assessment of sarcopenia, this remains to be verified. In this study, we examined the reliability and optimal diagnostic score of the CS-30 for assessing sarcopenia in elderly Japanese participants. METHODS: This cross-sectional study included 678 participants (443 females and 235 males) who underwent the test for sarcopenia as per the Asian Working Group for Sarcopenia (AWGS) 2019, the CS-30 test, and the isometric knee-extension muscle strength test. ROC analysis was used to estimate the optimal CS-30 scores at which sarcopenia was detected. RESULTS: CS-30 scores were positively associated with sarcopenia (OR: 0.88; 95% CI:0.82-0.93). The AUC of the CS-30 for sarcopenia definition were 0.84 (p < 0.001) for females and 0.80 (p < 0.001) for males. The optimal number of stands in the CS-30 that predicted sarcopenia was 15 for females (sensitivity, 76.4%; specificity, 76.8%) and 17 for males (sensitivity, 75.0%; specificity, 71.7%). CONCLUSIONS: The CS-30 was found to be a reliable test for sarcopenia screening in the elderly Japanese population.

Automatic and Real-Time Computation of the 30-Seconds Chair-Stand Test without Professional Supervision for Community-Dwelling Older Adults.

The present paper describes a system for older people to self-administer the 30-s chair stand test (CST) at home without supervision. The system comprises a low-cost sensor to count sit-to-stand (SiSt) transitions, and an Android application to guide older people through the procedure. Two observational studies were conducted to test (i) the sensor in a supervised environment (n = 7; m = 83.29 years old, sd = 4.19; 5 female), and (ii) the complete system in an unsupervised one (n = 7; age 64-74 years old; 3 female). The participants in the supervised test were asked to perform a 30-s CST with the sensor, while a member of the research team manually counted valid transitions. Automatic and manual counts were perfectly correlated (Pearson's r = 1, p = 0.00). Even though the sample was small, none of the signals around the critical score were affected by harmful noise; p (harmless noise) = 1, 95% CI = (0.98, 1). The participants in the unsupervised test used the system in their homes for a month. None of them dropped out, and they reported it to be easy to use, comfortable, and easy to understand. Thus, the system is suitable to be used by older adults in their homes without professional supervision.

Portable Ultrasound-Based Device for Detecting Older Adults' Sit-to-Stand Transitions in Unsupervised 30-Second Chair-Stand Tests.

Lower-limb strength is a marker of functional decline in elders. This work studies the feasibility of using the quasi-periodic nature of the distance between a subjects' back and the chair backrest during a 30-s chair-stand test (CST) to carry out unsupervised measurements based on readings from a low-cost ultrasound sensor. The device comprises an ultrasound sensor, an Arduino UNO board, and a Bluetooth module. Sit-to-stand transitions are identified by filtering the signal with a moving minimum filter and comparing the output to an adaptive threshold. An inter-rater reliability (IRR) study was carried out to validate the device ability to count the same number of valid transitions as the gold-standard manual count. A group of elders (age: mean (m) = 80.79 years old, SD = 5.38; gender: 21 female and seven male) were asked to perform a 30-s CST using the device while a trained nurse manually counted valid transitions. Ultimately, a moving minimum filter was necessary to cancel the effect of outliers, likely produced because older people tend to produce more motion artefacts and, thus, noisier signals. While the intra-class correlation coefficient (ICC) for this study was good (ICC = 0.86, 95% confidence interval (CI) = 0.73, 0.93), it is not yet clear whether the results are sufficient to support clinical decision-making.

[Evaluation of the relationship between the parameters of peripheral skeletal and respiratory muscles in patients with chronic obstructive pulmonary disease].

Chronic obstructive pulmonary disease (COPD) is a group of diseases with high levels of comorbidity. Pathological changes of peripheral skeletal and respiratory muscles in COPD patients, which are often underestimated, occupy a special place. AIM: To study the relationship between functional and quantitative parameters of the peripheral (limb muscle) and respiratory muscles in COPD patients. MATERIALS AND METHODS: 127 patients (98 men/29 women, mean age 67.68.2 years) were under observation without acute COPD. All COPD patients were classified according to GOLD (2019) into groups A, B, C, D. The algorithm of the European Working Group on Sarcopenia in Older People (EWGSOP2) was used to diagnose sarcopenia. The muscle mass was measured using dual energy X-ray absorptiometry (DXA) and the appendicular lean mass index (ASM) was estimated. Maximal inspiratory pressure (MIP) and maximal expiratory pressure (MEP) were measured by body plethysmograph MasterScreen Body. Quantitative assessment of thoracic muscle cross-sectional areas were performed using the CT scan using Vidar Dicom Viewer software. RESULTS: Sarcopenia was diagnosed in 43.3% of COPD patients. Respiratory muscle dysfunction was determined in 66.1% of patients with COPD, its probability increased in groups C and D in comparison with groups A and B [chance ratio 6.6 (95% confidence interval 2.915.0); p0.0001]. Correlations between the functional parameters of sarcopenia and respiratory muscle strength as well as between the mass of peripheral skeletal muscles and respiratory muscle area have been established according to the data of computerized tomography (р0.01). Sarcopenia as well as respiratory muscle dysfunction was observed more frequently in persons with severe and extremely severe airway obstruction and in patients with predominantly emphysematic COPD phenotype (p0.01). CONCLUSION: Sarcopenia is a frequent comorbidity in COPD and its development is connected with the severity of the course of the main disease. Correlation between parameters of peripheral (limb muscle) and respiratory muscles in patients with COPD has been determined.

The impact of muscle function, muscle mass and sarcopenia on independent ageing in very old Swedish men.

BACKGROUND: Preserved functions of daily life and cognition are cornerstones of independent aging, which is crucial for maintaining a high quality of life. The aim of this study was to examine the impact of sarcopenia, and its underlying components, on independent ageing in a cohort study of very old men. METHODS: The presence of sarcopenia and independent ageing at a mean age of 87 was investigated in 287 men from the Uppsala Longitudinal Study of Adult Men. Five years later 127 men were re-evaluated for independent ageing. Sarcopenia was defined by two different definitions from the European Working Group on Sarcopenia in Older People. In the first definition sarcopenia was defined as skeletal muscle index < 7.26 kg/m2 and either gait speed ≤0.8 m/s or hand grip strength < 30 kg. In the later up-dated definition, HGS < 27 kg and/or chair stand test > 15 s defines probable sarcopenia, which is confirmed by SMI < 7.0 kg/m2. Independent ageing was defined as a Mini-Mental State Examination score of ≥25 points, absence of diagnosed dementia, community-dwelling, independency in personal care and ability to walk outdoors alone. RESULTS: Sarcopenia at baseline was observed in 21% (60/287) and 20% (58/287), respectively, due to definition. The prevalence of independent ageing was 83% (239/288) at baseline and 69% (87/127) five years later. None of the sarcopenia diagnoses were associated with independent ageing. In contrast, gait speed was both in cross-sectional (odds ratio (OR) per one standard deviation increase 2.15, 95% confidence interval (CI) 1.47-3.15), and in longitudinal multivariate analyses (OR 1.84, 95% CI 1.19-2.82). In the cross-sectional analysis also higher hand grip strength was associated with independent ageing (OR 1.58, 95% CI 1.12-2.22), while a slower chair stand test was inversely associated (OR 0.61, 95% CI 0.43-0.86). Muscle mass; i.e. skeletal muscle index, was not associated with independent ageing. CONCLUSIONS: For very old men, especially a higher gait speed, but also a higher hand grip strength and a faster chair stand test, were associated with independent ageing, while skeletal muscle index alone, and the composite sarcopenia phenotype measured with two different definitions, were not.

Comparison between eccentric and concentric resistance exercise training without equipment for changes in muscle strength and functional fitness of older adults.

PURPOSE: The present study tested the hypothesis that resistance exercise training focusing on eccentric muscle contractions would improve muscle strength and functional physical fitness more than concentric contraction-focused resistance training in older adults. METHODS: Healthy older adults (65-84 years) were placed into eccentric (ECC; n = 9) or concentric training group (CON; n = 8). They performed 4-6 basic manual resistance exercises focusing on either eccentric or concentric muscle contractions once at a community centre and at least twice at home a week for 8 weeks. Muscle thickness of the quadriceps femoris (MT), knee extensor maximal voluntary isometric contraction strength (MVC), 30-second chair stand (CS), 3-metre timed up and go (TUG), 2-minute step (2MS), sit and reach (SR), and static balance with eyes open and closed (Bal-EC) were assessed before and 7 days after the last community centre session. RESULTS: Changes in MT (ECC: 21.6 ± 9.2% vs CON: 6.7 ± 7.1%), MVC (38.3 ± 22.6% vs 8.2 ± 8.4%), CS (51.0 ± 21.7% vs 34.6 ± 28.3%), TUG (16.7 ± 9.9% vs 6.3 ± 7.7%), 2MS (9.9 ± 6.0% vs 6.0 ± 7.3%) and Bal-EC (35.1 ± 6.7% vs 8.8 ± 16.2%) from baseline were greater (P < 0.05) for the ECC than the CON group. CONCLUSION: These results show that the eccentric manual resistance exercise training was more effective for improving lower limb strength, mobility, and postural stability of older adults when compared with the concentric training. This suggests the significance of emphasising eccentric muscle contractions in movements to maintain and improve physical function.

Older Adults with Weaker Muscle Strength Stand up from a Sitting Position with More Dynamic Trunk Use.

The ability to stand up from a sitting position is essential for older adults to live independently. Body-fixed inertial sensors may provide an approach for quantifying the sit-to-stand (STS) in clinical settings. The aim of this study was to determine whether measurements of STS movements using body-fixed sensors yield parameters that are informative regarding changes in STS performance in older adults with reduced muscle strength. In twenty-seven healthy older adults, handgrip strength was assessed as a proxy for overall muscle strength. Subjects were asked to stand up from a chair placed at three heights. Trunk movements were measured using an inertial sensor fixed to the back. Duration, angular range, and maximum angular velocity of STS phases, as well as the vertical velocity of the extension phase, were calculated. Backwards elimination using Generalized Estimating Equations was used to determine if handgrip strength predicted the STS durations and trunk kinematics. Weaker subjects (i.e., with lower handgrip strength) were slower during the STS and showed a larger flexion angular range and a larger extension angular range. In addition, weaker subjects showed a greater maximum angular velocity, which increased with lower seat heights. Measurements with a single inertial sensor did reveal that older adults with lower handgrip strength employed a different strategy to stand up from a sitting position, involving more dynamic use of the trunk. This effect was greatest when elevating body mass. Trunk kinematic parameters were more sensitive to reduced muscle strength than durations.