Preserving Mobility in Older Adults with Physical Frailty and Sarcopenia: Opportunities, Challenges, and Recommendations for Physical Activity Interventions

Lower limb strength and depression: a national cross-sectional study of an elderly population in China

BACKGROUND

The relationship between lower limb strength and depression in the elderly remains underexplored. This study aims to investigate this relationship using representative samples from China.

METHODS

A total of 3421 elderly people aged 60 and above from the China Health and Retirement Longitudinal Study (CHARLS) were included. Five Times Sit-to-Stand (5TSTS) test was used to group the strength of lower limbs, and subjects' demographic characteristics, lifestyle behaviour and health index were evaluated. After adjusting the related variables, the relationship between lower limb strength and depression was determined by logistic regression model, and whether the relationship between lower limb strength and depression was related to different ages was further studied.

RESULTS

There were 1222 (35.7%) participants suffering from depression. Higher lower limb strength was associated with a lower likelihood of depression. Compared to the weakest group (Q1), those with stronger lower limb strength had significantly lower adjusted odds ratio (OR) for depression: OR ranged from 0.722 (95% CI: 0.589-0.886) to 0.446 (95% CI: 0.359-0.553). The relationship between lower limb strength and depression varied by age.

LIMITATIONS

This cross-sectional study cannot establish causality. Additionally, depression assessment relied on self-reports, which may introduce bias. Future longitudinal studies should consider other psychological and social factors to comprehensively understand the determinants of depression in the elderly.

CONCLUSION

There is a correlation between lower limb strength and depression, that is, the incidence of depressive symptoms in the elderly with better lower limb strength is lower, and this significant correlation has been proved in both sexes and almost all age groups.

The interplay between lying, sitting, standing, moving, and walking on obesity risk in older adults: a compositional and isotemporal substitution analysis

INTRODUCTION

Obesity in older adults is linked to various chronic conditions and decreased quality of life. Traditional physical activity guidelines often overlook the specific postures and movements that older adults engage in daily. This study aims to explore the compositional associations between posture-specific behaviours and obesity risk in younger (M = 67.35 ± 2.03 years) and older (M = 75.73 ± 4.17 years) groups of older adults and investigate the differences in body mass index (BMI) associated with replacing time spent in lying, sitting and standing with moving or walking.

METHODS

This cross-sectional study involved 309 older adults aged 65 and above from Czech Republic. Participants' movement behaviours, including lying, sitting, standing, moving, and walking, were measured using accelerometers. The data were analysed using compositional data analysis (CoDA) and isotemporal substitution models to assess the impact of reallocating time between different activities on self-reported (BMI).

RESULTS

The younger group engaged in more overall movement (193.84 min/day vs. 172.41 min/day) and walking (92.15 min/day vs. 76.62 min/day) than the older group. Significant estimated increases in BMI were associated with reallocating 30 min from movement to lying, sitting, or standing (up to + 3.31 kg/m²), while reallocating the same amount of time from lying, sitting, or standing to movement was associated with estimated reductions in BMI (up to - 2.54 kg/m²). In the older group, reallocating time from slow walking to lying or sitting was associated with estimated increases in BMI (up to + 1.86 kg/m²), while increasing time spent slow walking at the expense of lying or sitting theoretically reduced BMI (up to - 0.95 kg/m²).

CONCLUSIONS

The findings suggest that promoting movement and walking, including both slow and fast walking, may play a role in managing obesity risk in older adults. This study highlights the potential benefits of reducing sedentary time and encouraging low-intensity physical activity tailored to the capabilities of seniors, especially those aged 70+, as a possible strategy to mitigate obesity risk. However, further longitudinal studies are needed to confirm these associations and explore causal relationships.

Physical Exercise Intervention Characteristics and Outcomes in Frail and Pre-Frail Older Adults

(1) Background: Frailty is a multifactorial syndrome that significantly impacts the functional abilities of older adults, making them more vulnerable to falls, disabilities, and dependence. Exercise can serve as an effective intervention for pre-frail and frail older adults, improving muscle strength and reducing the risk of falls. This research aims to clarify the physical exercise protocols and their outcomes for this population. (2) Methods: A scoping review was conducted to summarize the evidence on physical activity parameters for frail and pre-frail older adults. The search included primary evidence sources published in PubMed, PEDro, Biomed, Scopus, and Springer, as well as search engines like Google Scholar and Dialnet. The keywords used were ([frailty] OR [frail] AND [exercise]). The PEDro and MINORS scales were used to assess the quality of the evidence and evaluate the risk of bias. (3) Results: Eighteen studies met the eligibility criteria. The most commonly reported exercise program was multicomponent, which included aerobic activities at 70% of the maximum effort and strength exercises at 20% to 80% of the participants' maximum capacity. This approach proved effective for this population. (4) Conclusions: The studies suggest that exercise is a successful intervention strategy for addressing frailty. However, not all the articles provided adequate information regarding the dosing of their interventions.

Meeting Aerobic Physical Activity Guidelines and Associations With Physical Fitness in Men With Metastatic Prostate Cancer: Baseline Results of the Multicentre INTERVAL-GAP4 Trial

BACKGROUND

This study compared the physical activity level of men with metastatic prostate cancer at baseline of the multicentre INTERVAL-GAP4 trial to the American Cancer Society guidelines and examined associations with physical fitness.

METHODS

A total of 140 men on androgen deprivation therapy (ADT) were included in this cross-sectional analysis of baseline data from the INTERVAL-GAP4 trial. Exclusion criteria included a maximum of 1 h of vigorous aerobic exercise or one structured resistance exercise session per week but no restrictions on habitual physical activity. Moderate-to-vigorous physical activity (MVPA) was assessed using a modified Godin-Shephard Leisure-Time Physical Activity Questionnaire. Physical fitness measurements included peak oxygen consumption (VO2peak), maximal power output (Wmax), 400 m walk time, one-repetition maximum (1RM) of leg extension, leg press, chest press and seated row, and handgrip strength. Quantile regression was used to analyse associations of MVPA with physical fitness outcomes at the 25th, 50th and 75th percentiles of the physical fitness distributions.

RESULTS

Total self-reported MVPA was 60 (IQR: 0, 180) min per week, with 29% meeting the aerobic physical activity guidelines. There was a statistically significant association of higher MVPA with higher relative VO2peak at the 25th (β = 0.53, p = 0.020) and 75th percentiles (β = 0.66, p = 0.001), relative Wmax at the 25th (β = 0.05, p = 0.003), 50th (β = 0.05, p = 0.009) and 75th percentiles (β = 0.07, p = 0.004) and reduced 400 m walk time at the 75th percentile (β = -4.26, p = 0.023), with β corresponding to the change in the dependent variable for each one-hour increase in weekly MVPA.

CONCLUSION

Few men recruited to the INTERVAL-GAP4 trial were meeting aerobic physical activity guidelines at baseline. Higher MVPA was associated with better aerobic capacity and walking performance but not maximal strength in men with metastatic prostate cancer on ADT.

TRIAL REGISTRATION

ClinicalTrials.gov: NCT02730338; German Clinical Trials Register: DRKS00010310.

Heterogeneous effects of socio-economic status on social engagement level among Chinese older adults: evidence from CHARLS 2020

Introduction

Older adults benefit from social connections as it aids in their adjustment to the physical and psychological changes that come with aging, thereby improving their health, well-being, and overall quality of life.

Methods

This study utilizes data from the 2020 China Health and Retirement Longitudinal Study (CHARLS) to investigate the influence of Socio-economic Status (SES) on the social activity levels of older persons and the disparities observed among demographic groups, employing the Heckman two-stage analysis and heterogeneity analysis.

Results

The results indicate that SES has a significant positive impact on the social engagement of older adults, and this effect varies across different older groups, with women, married individuals living with a spouse, urban residents, those aged 70-79, and individuals with average health conditions.

Discussion

To effectively address the social needs of older adults, it is essential to prioritize integrating cohesive structural methods that improve social connections. Establishing solid and sustainable social support mechanisms and meeting the social needs of older adults across various SES and demographic groups are crucial in promoting active and healthy aging.

A study of the correlation between sarcopenia and cognitive impairment in older individuals over 60 years: cross-sectional and longitudinal validation

Objective

To validate the correlation between sarcopenia and cognition, and explore cognitive subdomains affected by sarcopenia.

Methods

A case-control study was designed to recruit 90 individuals aged 60 and above from June to October 2023 in the same community, all individuals meeting the inclusion criteria were categorized according to the 2019 Asian criteria for sarcopenia and divided into the sarcopenia group and non-sarcopenia group at baseline. After a 12-week follow-up recording, individuals were classified into the aggravation group and alleviation group based on the change of sarcopenia severity. Sarcopenia tests including muscle mass, calf circumference, grip strength and physical function assessment, using Montreal Cognitive Assessment (MoCA) of nine dimensions for cognitive assessment.

Results

(1) There was a significant positive correlation between cognitive function and grip strength in males (r = 0.42, p < 0.05). (2) There was a moderate correlation between sarcopenia grading and MoCA score (r = -0.4, p < 0.001). (3) Individuals with sarcopenia had significantly lower MoCA total scores and sub-scores in executive function, fluency, calculation and delayed recall compared to non-sarcopenia group (p < 0.05). (4) After 12 weeks, the mean value of the change in fluency in the alleviation group increased by 0.33 points, while the aggravation group decreased by 0.2 points (W = 128, p < 0.05).

Conclusion

There is a correlation between sarcopenia and cognitive function, individuals with sarcopenia performing poorly in overall cognition as well as refined dimensions. The degree of cognition like fluency degenerates over time with increasing severity of sarcopenia.

Knee proprioception, muscle strength, and stability in Type 2 Diabetes Mellitus- A cross-sectional study

Background

The burgeoning prevalence of Type 2 Diabetes Mellitus (T2DM) has been linked to a spectrum of health complications, including those affecting the musculoskeletal system. Knee proprioception, muscle strength, and stability are essential for maintaining functional mobility and preventing falls, yet their relationship with T2DM is not fully elucidated.

Objectives

This study aimed to compare knee proprioception, muscle strength, and limits of stability (LOS) between individuals with T2DM and asymptomatic controls and to examine the moderating role of physical activity on these relationships.

Methods

In a cross-sectional design, 192 participants (96 with T2DM and 96 asymptomatic) underwent assessments for knee proprioception using a digital inclinometer, muscle strength via a handheld dynamometer, and LOS through dynamic posturography, graded as a percentage of maximum lean without losing balance.

Results

Our analysis revealed that individuals with T2DM demonstrated reduced knee muscle strength, with mean differences of 12.90 Nm (right) and 18.80 Nm (left) in 25° of flexion, and 25.78 Nm (right) and 26.36 Nm (left) in 40° of flexion, compared to asymptomatic controls. Proprioception errors were greater in the T2DM group (p < 0.001), with significant deficits noted in both knee 25° of flexion and 40° of flexion. Stability limits were also compromised, with the T2DM group displaying a decreased ability to maintain balance across all tested directions (p < 0.001). Physical activity emerged as a positive moderator, with higher activity levels correlating with improved muscle strength and stability.

Conclusion

T2DM significantly impairs musculoskeletal function, highlighting the need for integrated management strategies. The study underscores the importance of physical activity in mitigating T2DM-related musculoskeletal deterioration, suggesting that therapeutic interventions should include a focus on enhancing muscle strength and stability to improve the quality of life in this population.

Steatosarcopenia: A New Terminology for Clinical Conditions Related to Body Composition Classification

Body composition analysis focuses on measuring skeletal muscle mass and total body fat. The loss of muscle function and mass is related to clinical conditions such as frailty, increased risk of falls, and prolonged hospitalizations. Despite the relevance of the definition of sarcopenic obesity, there is still a gap in the monitoring of patients who have the combination of sarcopenia and myosteatosis, regardless of the presence of obesity. Therefore, we propose a new nomenclature, steatosarcopenia, a condition characterized by the loss of mass or skeletal muscle strength and performance associated with the excessive deposition of ectopic reserve fat in muscle tissue, in the same individual, not necessarily related to excess fat total body mass. A greater understanding of this condition may assist in developing strategies for preventing and treating metabolic diseases.

Bioelectrical impedance analysis-derived phase angle predicts possible Sarcopenia in patients on maintenance hemodialysis: a retrospective study

BACKGROUND

The prevalence of possible sarcopenia is notably high among maintenance hemodialysis (MHD) patients. Possible sarcopenia, defined as a decrease in muscle strength and/or somatic function, is an early and reversible condition between non-sarcopenic and sarcopenia, and early recognition and intervention for possible sarcopenia is important for preventing adverse outcomes and improving the quality of life of these patients. This study aimed to establish a simple and effective model for screening and identifying MHD patients at high risk of possible sarcopenia by using 50 kHz-Whole Body Phase Angle (PhA), with a specific focus on gender differences.

METHODS

This prospective cross-sectional study was conducted from September to December 2023 at the Wenjiang Hemodialysis Center in the Department of Nephrology, West China Hospital, Sichuan University, Chengdu, China. A total of 244 MHD patients, including 130 males and 114 females, were enrolled. Data were collected prospectively, including demographic information and physical measurements. All participants provided informed consent before enrollment. Measurements were taken post-dialysis to ensure consistency. The whole-body phase angle was measured using the InBody S10 device, grip strength was measured using an electronic grip strength tester, and physical function was assessed by the Short Physical Performance Battery (SPPB). The Skeletal Muscle Index (SMI) was also calculated.

RESULTS

A total of 244 patients receiving hemodialysis were enrolled in this study. Among these, 109 patients were categorized as non-sarcopenic, 111 as having possible sarcopenia, and 24 as sarcopenic. The prevalence of sarcopenia among MHD patients is 9.8%, while the prevalence of possible sarcopenia is 45.5%. The receiver operating characteristic (ROC) curve analysis showed that for male patients, the AUC of PhA for predicting possible sarcopenia was 0.798, with a sensitivity of 80.36%, specificity of 69.70%, and a cutoff value of 6.20°. For female patients, the AUC of PhA was 0.701, with a sensitivity of 70.91% and specificity of 62.79%, and a cutoff value of 5.70°.

CONCLUSIONS

PhA may be a useful and simple predictor of the risk of possible sarcopenia in MHD patients, and more research is needed to further promote the use of PhA in possible sarcopenia.

Multi-branch deep learning neural network prediction model for the development of angular biosensors based on sEMG

Introduction

Human gait motion intention recognition is very important for the lower extremity exoskeleton robot to accurately synchronize and respond to the user's natural motion. And motion intention recognition is generally performed through sEMG. Deep learning neural networks perform well in dealing with high-dimensional data and nonlinear relationships such as sEMG, but different deep learning neural networks have their own advantages in dealing with different types of data. Therefore, a multi-branch deep learning neural network, which enables different neural networks to process different feature items, could achieve more accurate and efficient motion intention recognition. The purpose of this study is to 1) Establish a multi-branch deep learning neural network model to achieve accurate gait recognition and effective estimation of joint angles. 2) Quantify the performance of the multi-branch deep learning neural network model in gait recognition and joint angle prediction using sEMG.

Methodology

This study involved the collection of sEMG and plantar pressure data during walking in human subjects. Firstly, the collected signals are filtered and denoised to ensure the quality and reliability of the data. Calculate the time domain features and the frequency domain features to capture the key information of gait. Then, using the sensitivity difference of different structural neural networks to different feature data, a multi-branch deep learning neural network model is developed, in which the extracted features are used as the input of the model. The output of the model includes gait cycle and joint angle, so as to realize the accurate recognition of human gait and the effective estimation of joint angle.

Results

The results show that the proposed method has high accuracy in identifying human gait and estimating joint angles. The multi-branch neural network model successfully integrates time-domain and frequency-domain features and provides reliable prediction of gait cycle and joint angle. The highest accuracy of gait recognition is 95.42%, the lowest is 90.11%, and the average is 92.16%. The average error of joint angle estimation is 3.19.

Discussion

This study designed a human walking gait recognition and joint angle prediction model to achieve accurate human lower limb motion intention recognition.The model can be integrated into the sEMG sensor to design a angular biosensors, which can predict the human joint angle in real time.

The association between blood biological age at rehabilitation admission and physical activity during rehabilitation in geriatric inpatients: RESORT

Geriatric rehabilitation inpatients have high levels of sedentary behaviour (SB) and low levels of physical activity (PA). Biological age predicted by blood biomarkers is indicative of adverse outcomes. The objective was to determine the association between blood biological age at rehabilitation admission and levels of SB and PA during rehabilitation in geriatric inpatients. Inpatients admitted to geriatric rehabilitation wards at the Royal Melbourne Hospital (Melbourne, Australia) from October 22, 2019, to March 29, 2020, in the REStORing health of acute unwell adulTs (RESORT) observational cohort were included. Blood biological age was predicted using SenoClock-BloodAge, a hematological ageing clock. Patients wore an inertial sensor to measure SB and PA. Logistic regression analyses were conducted. A total of 111 patients (57.7% female) with mean age 83.3 ± 7.5 years were included in the analysis. The mean blood biological age was 82.7 ± 8.4 years. Patients with 1-year higher blood biological age had higher odds of having high SB measured as non-upright time greater than 23 h/day (odds ratio (OR): 1.050, 95% confidence interval (CI): 1.000-1.102). Individuals having 1-year higher age deviation trended towards lower odds of having high levels of PA measured as stepping time greater than 7.4 min/day (OR: 0.916, CI: 0.836-1.005) and as greater than 19.5 sit-to-stand transitions/day (OR: 0.915, CI: 0.836-1.002). In conclusion, higher biological age was associated with higher levels of SB and trended towards lower PA. Incorporating blood biological age could facilitate resource allocation and the development of more tailored rehabilitation plans.

Accuracy of four sarcopenia screening methods in patients with chronic stroke in Thailand: a cross-sectional study

AIMS

The aim of this study was to evaluate the accuracy of screening tools for sarcopenia and to determine whether the same or different cutoff points should be applied in patients with chronic stroke.

MATERIALS AND METHODS

Sixty-eight participants with residual hemiparetic deficit for over 6 months were enrolled. We evaluated the accuracy of calf circumference, SARC-F questionnaire, SARC-CalF, and Ishii's score chart using the Asia Working Group for Sarcopenia (AWGS) 2019 revised criteria as the gold standard.

RESULTS

Sarcopenia was identified in 22 participants (32.4%) based on the AWGS criteria. Overall, SARC-F showed the lowest diagnostic accuracy. The Area Under the receiver operating characteristic Curves (AUC) of calf circumference, SARC-F, SARC-CalF, and Ishii's score chart were 0.77 (95% confidence interval [CI], 0.66-0.88), 0.58 (95% CI, 0.42-0.74), 0.75 (95% CI, 0.62-0.87), and 0.78 (95% CI, 0.65-0.90), respectively. The mean AUC of SARC-F was inferior to SARC-CalF (0.58 vs. 0.75, p = 0.035).

CONCLUSIONS

The accuracy and diagnostic properties of calf circumference, SARC-CalF, and Ishii's score chart were comparable (mean AUC of 0.77, 0.75, and 0.78, respectively). SARC-F showed the lowest accuracy (mean AUC = 0.58). The recommended screening tools are calf circumference, SARC-CalF, and Ishii's score chart. It is not recommended to rely solely on SARC-F for screening sarcopenia after stroke. We proposed potential new cutoff points for each screening instrument, including SARC-F, SARC-CalF, calf circumference in women, and Ishii's score chart for both men and women.

Ten-Year Results of the Fitmore® Hip Stem with a Focus on Varus/Valgus Alignment and Subsidence-A Retrospective Monocentric Analysis

Background: Hip arthroplasty is a common elective surgery worldwide, with rising numbers due to demographic changes and an emphasis on maintaining physical activity in the elderly. The development of new implant designs, especially shorter uncemented stems, has contributed to the advancement of minimally invasive implantation techniques. However, the long-term in vivo behaviour of these implants, particularly regarding subsidence, stability, and stress shielding, remains to be fully understood. Methods: This retrospective, monocentric cohort study analyses the long-term radiographic outcomes of the first 141 patients who underwent total hip arthroplasty with the Fitmore® Hip Stem between June 2007 and December 2008. It focuses on subsidence, stability, varus-valgus alignment, and the influence of patient-related, anatomical, and surgical factors on implant behaviour over a 10-year follow-up period. Results: The average change in varus/valgus alignment was 0.7° into varus and the average subsidence was 1.7 mm over 10 years, with most changes occurring within the first six weeks postoperatively. The varus-valgus alignment and subsidence did not significantly change after the first year, indicating stable osteointegration of the implant. Neither patient factors (gender, age) nor surgical and implant factors (implantation angle, approach, stem family, size, total offset) had a significant influence on the long-term behaviour of the implant. Conclusions: The Fitmore® Hip Stem shows highly reliable long-term stability and integration, unaffected by various patient, surgical, and implant factors, as confirmed by excellent register data. Nevertheless, monitoring of this and other new implants should be continued in order to determine implant behaviour, possible weaknesses, and indication limits at an early stage for the benefit of the patient.

Prevalence of and factors associated with cognitive frailty in elderly patients with chronic obstructive pulmonary disease: A cross-sectional study

The status of cognitive frailty in elderly patients with chronic obstructive pulmonary disease (COPD) and its influencing factors in China remains unclear. This study aimed to investigate the prevalence of and factors associated with cognitive frailty in elderly patients with COPD. This cross-sectional study enrolled elderly patients with stable COPD between May and November 2022 from the Respiratory Department of the First Affiliated Hospital of Zhengzhou University and the Fifth Affiliated Hospital of Zhengzhou University. Convenience sampling method was adopted. Frailty Phenotype scale, Montreal Cognitive Assessment scale, Geriatric Depression Scale, and Clinical Dementia Rating scale were used to assess the prevalence of cognitive frailty in elderly patients with COPD. Multivariable logistic regression analysis was used to explore the associated factors. A total of 406 valid questionnaires were collected, and 173 patients (35.6%) had cognitive frailty. Binary logistic regression analysis showed that sex (odds ratio [OR] = 0.009; 95%CI: 0.001-0.770; P = .038), depression (OR = 17.780; 95%CI: 1.092-289.478; P = .043), modified Medical Research Council grade 1-3 (OR = 28.394-4095.683; 95%CI: 1.086-4,592,652.211; P < .05), global initiative for chronic obstructive lung disease grade 2 and 3 (OR = 32.508-282.072; 95%CI: 1.101-12,516.874; P < .05), and frequencies of acute exacerbations of COPD and hospitalizations within 1 year of 2 times (OR = 21.907; 95%CI: 4.587-104.622; P < .001) were independently associated with cognitive frailty. The prevalence of cognitive frailty in elderly patients with stable COPD was high. Female, depression, modified Medical Research Council grade, global initiative for chronic obstructive lung disease grade, and frequencies of acute exacerbations of COPD and hospitalizations within 1 year might be the factors independently associated with cognitive frailty, educational level might be a protective associated factor for cognitive frailty.

A 6-month educational program improves sleep behaviour in community-dwelling frail older adults: A randomised controlled trial

BACKGROUND

The prevalence of sleep-related issues among older adults is a significant concern, with half of the older population reporting these problems. Consequently, strategies to improve sleep are needed for this population. This study aims to assess the effects of a health educational program on sleep behaviour among pre-frail or frail older adults residing in the community and to explore possible associations with frailty.

METHODS

This randomised controlled trial (NCT05610605) included a total of 197 community-dwelling older adults with frailty/pre-frailty, divided into control (n = 88) and educational (n = 109) groups, were assessed at baseline, after the 6-month educational program (6 months), and 6 months after the intervention (12 months). The intervention comprised four group sessions and six follow-up phone calls, focusing on frailty, physical activity, dietary habits, and cognitive training. Sleep quality was measured using the Pittsburgh Sleep Quality Index (PSQI) and wrist-worn accelerometry.

RESULTS

At 6 months, a significant time-by-group interaction was found for self-reported [β = -0.449, 95%CI (-0.844, -0.053), p = 0.026] and accelerometer-measured [β = 0.505, 95%CI (0.085, 0.926), p = 0.019] sleep efficiency, showing improved sleep efficiency in the intervention group vs. controls. A significant time-by-group interaction at 6 months was noted for sleep awakenings [β = -0.402, 95%CI (-0.825, -0.020), p = 0.047]. The educational program led to a significant decrease in awakenings, while the control group experienced an increase. The change in the number of awakenings (Rs = 0.183, p = 0.020) at 6 months was significantly associated with changes in frailty. Moreover, a significant time-by-group interaction was reported at the 12-month assessment [β = -0.449, 95%CI (-0.844, -0.053), p = 0.026] for self-reported sleep quality, indicating better results in the intervention group compared to controls.

CONCLUSION

The educational program improved sleep quality and sleep efficiency while reducing the number of awakenings per night among community-dwelling frail older adults, offering a practical approach to addressing sleep-related challenges in this demographic.

Dietary vitamin K intake in relation to skeletal muscle mass and strength among adults: a cross-sectional study based on NHANES

Background

Previous studies revealed that vitamin K might help maintain muscle homeostasis, but this association has received little attention. We aimed to explore the associations of vitamin K intake with skeletal muscle mass and strength.

Methods

We included cross-sectional data from the U.S. National Health and Nutrition Examination Survey (NHANES, 2011-2018). Vitamin K intake was assessed via 24-h recall. Covariate-adjusted multiple linear regression and restricted cubic splines were used to evaluate the associations of dietary vitamin K intake with skeletal muscle mass and strength, measured by dual-energy X-ray absorptiometry and handgrip dynamometer, respectively.

Results

Dietary vitamin K intake was positively associated with skeletal muscle mass in males (β = 0.05747, p = 0.0204) but not in females. We also revealed a positive association between dietary vitamin K intake and handgrip strength within the range of 0-59.871 μg/d (P nonlinear = 0.049). However, beyond this threshold, increasing vitamin K intake did not cause additional handgrip strength improvements.

Conclusion

We provided evidence for a positive relationship between dietary vitamin K intake and skeletal muscle mass in males. Moreover, our study revealed a nonlinear relationship between dietary vitamin K intake and handgrip strength, highlighting an optimal intake range.

Difficulty with mobility among the aged in Ghana: Evidence from Wave 2 of the World Health Organization's Study on Global Ageing and Adult Health

BACKGROUND

Globally, the population is rapidly ageing, stemming from a recent decline in mortality, and an increase in life expectancy. About 727 million people globally were aged ≥65 in 2020, and 1 in 6 people will be ≥65 years by 2050. About 7% of Ghana's population was over 60 years in 2010, and projected to be 12% by 2050. However, the aged are confronted with degenerative conditions that translate into difficulty with mobility. The study was conducted to investigate the difficulty with mobility among the aged in Ghana.

METHODS

The study utilised a cross-sectional dataset of the 2014/2015 (wave 2) Study on Global Ageing and Adult Health and included 1,856 participants aged ≥50 years. The survey command was applied to adjust for sampling biases and the design of the study. At 5% alpha level, a chi-square test of independence was conducted to determine the association between dependent and independent variables. At 95% confidence interval and 5% alpha level, three-level multilevel logistic regression models were performed. The fixed-effects were presented in odds ratio and the random effects were presented using the Intra-Class Correlation. All analysis were performed using STATA statistical software version 16.0.

RESULTS

Out of the 1,856 participants, 40.3% had difficulty with mobility. Additionally, age (80 and above) [AOR = 3.05, 95%CI = 1.78-5.22], self-reported poor/bad health status [AOR = 2.39, 95%CI = 1.35-4.23], having severe/extreme difficulty performing household activities [AOR = 25.12, 95%CI = 11.49-44.91], experienced severe/extreme bodily pains [AOR = 4.56, 95%CI = 2.16-9.64], severe/extreme sleep problems [AOR = 4.15, 95%CI = 1.68-10.29], and participants with difficulty with sight/vision [AOR = 1.56, 95%CI = 1.16-2.10] had higher odds of difficulty with mobility.

CONCLUSION

The aged in Ghana had relatively higher prevalence (40.3%) of difficulty with mobility which is influenced by demographics, health status, and degeneration associated with ageing. This highlights the need to provide social support and strengthen social capital for the aged in Ghana, especially those with difficulty with vision, experiencing bodily pains and had poor health status. Additionally, the Government and stakeholders should provide assistive devices for the aged and geriatric care including recreational fields and care homes to address the health and physical needs of the aged in Ghana.

Serious leisure and successful aging among elderly air volleyball players: examining the mediating role of social support and flow experience

Introduction

Previous literature has demonstrated that engagement in serious leisure (SL) is associated with subjective well-being among older adults, while the relationship between successful aging (SA) and SL remains unexplored. This study aims to investigated the association between SL, social support (SS), flow experience (FE), and SA.

Methods

A total of 435 older adults participating in air volleyball events were included in this study.

Results

The findings revealed that: (i) SL directly and positively influences on SS, FE, and SA; (ii) SS is positively related to FE, and FE is positively associated with older adults'SA; (iii) Both SS and FE fully mediate the relationship between SL and SA, with SS partially explaining this mediation through FE.

Discussion

This study builds upon prior research in this field and highlights the significance of SL for the SA among older adults. Future studies should further explore the underlying mechanisms linking serious sport experiences to successful elderly life.

Physical activity intensity, frequency, duration, volume and the risk of possible sarcopenia in middle-aged and older adults

This study explored the association of physical activity (PA) from different dimensions including intensity, frequency, duration, and volume with possible sarcopenia (PSA), and established the PA cut-off value to identify PSA in middle-aged and older adults. The data in this study were from the China Health and Retirement Longitudinal Study in 2015. There were 7,957 adults aged over 45 years in the analysis. PA was assessed using a modified version of the International Physical Activity Questionnaire Short Form. Muscle strength and physical performance were measured to define PSA. Results showed that men spending at least 3 days each week, more than 10 min each time on vigorous-intensity PA, or a minimum of 933 Mets on total PA each week had a lower risk of PSA. In women, spending at least 3 days each week, more than 30 min each time on moderate-intensity PA, or taking at least 6 days each week, more than 120 min each time on low-intensity PA, or a minimum of 933 Mets on total PA each week was associated with a lower risk of PSA. In older adults (≥ 65 years), spending at least one day each week, more than 30 min each time on vigorous-intensity PA, or taking a minimum of 933 Mets on total PA each week was linked with a decreased risk of PSA. However, no significant associations were found between any PA dimensions and PSA in middle-aged adults (45-64 years). A receiver operating characteristic analysis showed that the PA cut-off value was 695 and 693 Mets each week for predicting PSA for men and women. The findings suggested that the intensity, frequency, duration, and weekly volume of PA is associated with the risk of PSA in middle-aged and older adults, and the association largely depends on sex and age. The PA cut-off value may be an early indication for a higher risk of sarcopenia.

Enhancing Mobility and Well-Being in Older Adults with Cancer

OBJECTIVE

To analyze mobility challenges in older adult with cancer.

METHODS

Data from previous literature was extracted and analyzed pertaining to the topic of interest.

RESULTS

Mobility issues for the older adult with cancer are multi-factorial and are impacted by age-related changes, comorbidities, cancer itself, and cancer treatment.

CONCLUSIONS

Proven benefits have been suggested with mobility assessments, exercise and dietary interventions, and cancer rehabilitation programs however further research is needed to define integration and utilization of programs, facilitation of cancer survivors returning to work, inclusion of socially disadvantaged patients, program compliance, economic aspects, and caregiver involvement to improve quality of life across the cancer continuum.

IMPLICATIONS FOR NURSING PRACTICE

Oncology nurses are in a key role to impact the care of the older adult with cancer with mobility through patient assessment of mobility function, facilitation of patient referrals for supportive services and cancer rehabilitation and execution of nurse-led intervention programs.

Dietary Protein and Physical Exercise for the Treatment of Sarcopenia

Sarcopenia is a multifactorial age-related disorder that causes a decrease in muscle mass, strength, and function, leading to alteration of movement, risk of falls, and hospitalization. This article aims to review recent findings on the factors underlying sarcopenia and the strategies required to delay and counteract its symptoms. We focus on molecular factors linked to ageing, on the role of low-grade chronic and acute inflammatory conditions such as cancer, which contributes to the onset of sarcopenia, and on the clinical criteria for its diagnosis. The use of drugs against sarcopenia is still subject to debate, and the suggested approaches to restore muscle health are based on adequate dietary protein intake and physical exercise. We also highlight the difference in the amount and quality of amino acids within animal- and plant-based diets, as studies have often shown varying results regarding their effect on sarcopenia in elderly people. In addition, many studies have reported that non-pharmacological approaches, such as an optimization of dietary protein intake and training programs based on resistance exercise, can be effective in preventing and delaying sarcopenia. These approaches not only improve the maintenance of skeletal muscle function, but also reduce health care costs and improve life expectancy and quality in elderly people.

Rheological Analysis and Evaluation of Measurement Techniques for Curing Poly(Methyl Methacrylate) Bone Cement in Vertebroplasty

Vertebroplasty is a minimally invasive surgical procedure used to treat vertebral fractures, which conventionally involves injecting poly(methyl methacrylate) (PMMA) bone cement into the fractured vertebra. A common risk associated with vertebroplasty is cement leaking out of the vertebra during the injection, which may occur due to a lack of understanding of the complex flow behavior. Therefore, experiments to quantify the cement's flow properties are necessary for understanding and proper handling of the bone cement. In this study, we aimed to characterize the behavior of PMMA bone cement in its curing stages to obtain parameters that govern the flow behavior during injection. We used rotational and oscillatory rheometry for our measurements, as well as a custom-made injector setup that replicated a typical vertebroplasty setting. Our results showed that the complex viscoelastic behavior of bone cement is significantly affected by deformations and temperature. We found that the results from rotational tests, often used for characterizing the bone cement, are susceptible to measurement artifacts caused by wall slip and "ridge"-like formations in the test sample. We also found the Cox-Merz rule to be conditionally valid, which affects the use of oscillatory tests to obtain the shear-thinning characteristics of bone cement. Our findings identify important differences in the measured flow behavior of PMMA bone cement when assessed by different rheological methods, an understanding that is crucial for its risk-free usage in downstream medical applications.

Unveiling the Intricate Dance: How Cancer Orchestrates Muscle Wasting and Sarcopenia

Sarcopenia is a prevalent and clinically significant condition, particularly among older age groups and those with chronic disease. Patients with cancer frequently suffer from sarcopenia and progressive loss of muscle mass, strength, and function. The complex interplay between cancer and its treatment, including medical therapy, radiotherapy, and surgery, significantly contributes to the onset and worsening of sarcopenia. Cancer induces muscle wasting through inflammatory processes, metabolic alterations, and hormonal imbalance. Moreover, medical and radiation therapies exert direct toxic effects on muscles, contributing to the impairment of physical function. Loss of appetite, malnutrition, and physical inactivity further exacerbate muscle wasting in cancer patients. Imaging techniques are the cornerstones for sarcopenia diagnosis. Magnetic resonance imaging, computed tomography, and dual-energy X-ray absorptiometry provide valuable insights into muscle structure and quality. Although each modality has advantages and limitations, magnetic resonance imaging produces high-resolution images and provides dynamic information about muscle function. Despite these challenges, addressing sarcopenia is essential for optimizing treatment outcomes and improving survival rates in patients with cancer. This review explored the factors contributing to sarcopenia in oncologic patients, emphasizing the importance of early detection and comprehensive management strategies.

Performance of digital technologies in assessing fall risks among older adults with cognitive impairment: a systematic review

Older adults with cognitive impairment (CI) are twice as likely to fall compared to the general older adult population. Traditional fall risk assessments may not be suitable for older adults with CI due to their reliance on attention and recall. Hence, there is an interest in using objective technology-based fall risk assessment tools to assess falls within this population. This systematic review aims to evaluate the features and performance of technology-based fall risk assessment tools for older adults with CI. A systematic search was conducted across several databases such as PubMed and IEEE Xplore, resulting in the inclusion of 22 studies. Most studies focused on participants with dementia. The technologies included sensors, mobile applications, motion capture, and virtual reality. Fall risk assessments were conducted in the community, laboratory, and institutional settings; with studies incorporating continuous monitoring of older adults in everyday environments. Studies used a combination of technology-based inputs of gait parameters, socio-demographic indicators, and clinical assessments. However, many missed the opportunity to include cognitive performance inputs as predictors to fall risk. The findings of this review support the use of technology-based fall risk assessment tools for older adults with CI. Further advancements incorporating cognitive measures and additional longitudinal studies are needed to improve the effectiveness and clinical applications of these assessment tools. Additional work is also required to compare the performance of existing methods for fall risk assessment, technology-based fall risk assessments, and the combination of these approaches.

The role of the extracellular matrix in the reduction of lateral force transmission in muscle bundles: A finite element analysis

BACKGROUND AND OBJECTIVE

Aging is associated with a reduction in muscle performance, but muscle weakness is characterized by a much greater loss of force loss compared to mass loss. The aim of this work is to assess the contribution of the extracellular matrix (ECM) to the lateral transmission of force in humans and the loss of transmitted force due to age-related modifications.

METHODS

Finite element models of muscle bundles are developed for young and elderly human subjects, by considering a few fibers connected through an ECM layer. Bundles of young and elderly subjects are assumed to differ in terms of ECM thickness, as observed experimentally. A three-element-based Hill model is adopted to describe the active behavior of muscle fibers, while the ECM is modeled assuming an isotropic hyperelastic neo-Hookean constitutive formulation. Numerical analyses are carried out by mimicking, at the scale of a bundle, two experimental protocols from the literature.

RESULTS

When comparing numerical results obtained for bundles of young and elderly subjects, a greater reduction in the total transmitted force is observed in the latter. The loss of transmitted force is 22 % for the elderly subjects, while it is limited to 7.5 % for the young subjects. The result for the elderly subjects is in line with literature studies on animal models, showing a reduction in the range of 20-34 %. This can be explained by an alteration in the mechanism of lateral force transmission due to the lower shear stiffness of the ECM in elderly subjects, related to its higher thickness.

CONCLUSIONS

Computational modeling allows to evaluate at the bundle level how the age-related increase of the ECM amount between fibers affects the lateral transmission of force. The results suggest that the observed increase in ECM thickness in aging alone can explain the reduction of the total transmitted force, due to the impaired lateral transmission of force of each fiber.

Prediction and mediation analysis for treatment responses to combined cognitive and physical training for older adults

Diminished cognitive and physical functions negatively affect the daily functions of individuals. Although combined cognitive and physical training prevents instrumental activities of daily living (IADL) disability in older adults, no predictive model or mediation analysis of IADL after combined training exists. This study aims to employ prediction and mediation analysis to identify the predictors of IADL performance and to elucidate the mediators of the association between baseline global cognition and subsequent IADL performance following combined cognitive and physical training. This study involved 177 participants aged 60 years and older who underwent combined training. Cognitive function was measured with the Montreal Cognitive Assessment (MoCA), Digit Symbol Substitution Test (DSST), Color Trails Test, Word List, and a dual task; physical function with the Timed Up and Go (TUG) test; daily function with the Lawton IADL Scale. We conducted regression analyses to identify the predictors of IADL performance, and mediation analysis to examine whether DSST and TUG mediate the relationship between MoCA and IADL. The pre-intervention DSST and TUG were significant independent predictors of post-intervention IADL. The association between the pre-intervention MoCA and post-intervention IADL was mediated by pre-intervention DSST and TUG. This study highlighted the importance of measuring and improving processing speed and functional mobility before and during interventions to enhance IADL outcomes.Trial registration: NCT03619577, 23/07/2018; NCT04689776, 29/12/2020.

Effects of integrated intrinsic foot muscle exercise with foot core training device on balance and body composition among community-dwelling adults aged 60 and above

BACKGROUND

Evidence on the effects of plantar intrinsic foot muscle exercise in older adults remains limited. This study aimed to evaluate the effect of an integrated intrinsic foot muscle exercise program with a novel three-dimensional printing foot core training device on balance and body composition in community-dwelling adults aged 60 and above.

METHODS

A total of 40 participants aged ≥ 60 years were enrolled in this quasi-experimental, single-group, pretest-posttest design; participants were categorized into two groups, those with balance impairment and those without balance impairment. The participants performed a 4-week integrated intrinsic foot muscle exercise program with a three-dimensional printing foot core training device. The short physical performance battery (SPPB) and timed up and go test were employed to evaluate mobility and balance. A foot pressure distribution analysis was conducted to assess static postural control. The appendicular skeletal muscle mass index and fat mass were measured by a segmental body composition monitor with bioelectrical impedance analysis. The Wilcoxon signed rank test was used to determine the difference before and after the exercise program.

RESULTS

Among the 40 enrolled participants (median age, 78.0 years; female, 80.0%; balance-impaired group, 27.5%), the 95% confidence ellipse area of the center of pressure under the eyes-closed condition was significantly decreased (median pretest: 217.3, interquartile range: 238.4; median posttest: 131.7, interquartile range: 199.5; P = 0.001) after the exercise. Female participants without balance impairment demonstrated a significant increase in appendicular skeletal muscle mass index and a decrease in fat mass. Participants in the balance-impaired group exhibited a significant increase in SPPB.

CONCLUSIONS

Integrated intrinsic foot muscle exercise with a three-dimensional printing foot core training device may improve balance and body composition in adults aged 60 and above.

TRIAL REGISTRATION

ClinicalTrials.gov ID: NCT05750888 (retrospectively registered 02/03/2023).

Physical Activity and Oxidative Stress in Aging

Biological aging, characterized by changes in metabolism and physicochemical properties of cells, has an impact on public health. Environment and lifestyle, including factors like diet and physical activity, seem to play a key role in healthy aging. Several studies have shown that regular physical activity can enhance antioxidant defense mechanisms, including the activity of enzymes such as superoxide dismutase (SOD), catalase, and glutathione peroxidase. However, intense or prolonged exercise can also lead to an increase in reactive oxygen species (ROS) production temporarily, resulting in oxidative stress. This phenomenon is referred to as "exercise-induced oxidative stress". The relationship between physical activity and oxidative stress in aging is complex and depends on various factors such as the type, intensity, duration, and frequency of exercise, as well as individual differences in antioxidant capacity and adaptation to exercise. In this review, we analyzed what is reported by several authors regarding the role of physical activity on oxidative stress in the aging process as well as the role of hormesis and physical exercise as tools for the prevention and treatment of sarcopenia, an aging-related disease. Finally, we reported what has recently been studied in relation to the effect of physical activity and sport on aging in women.

Feasibility and preliminary effects of a mindfulness-based physical exercise (MBPE) program for community-dwelling older people with sarcopenia: A protocol for a parallel, two-armed pilot randomised controlled trial

INTRODUCTION

Physical exercise (PE) is essential for alleviating the symptoms of sarcopenia. Low motivation is a major barrier to PE. Mindfulness-based intervention (MBI) has the potential to improve motivation. However, few studies have used a mindfulness-based PE (MBPE) intervention among older people with sarcopenia.

OBJECTIVES

To assess the feasibility, acceptability and preliminary effects of the MBPE program among community-dwelling older people with sarcopenia.

METHODS AND ANALYSIS

A two-arm pilot randomised controlled trial will be conducted to assess the feasibility, acceptability and preliminary effects of an MBPE program among community-dwelling older people with sarcopenia. A total of 60 participants will be randomised into the intervention group, receiving the MBPE intervention twice a week over 12 weeks, or the control group, receiving health education with the same duration, number of sessions and frequency as the intervention group. Each session of the MBPE program will last about 60 min, including 5-10- min introduction, 20-min MBI, 30-min PE and 5-10-min sharing and discussion. The primary outcomes will be the feasibility (i.e., the time spent recruiting participants, the eligibility rate and the recruitment rate) and acceptability (i.e., the attendance rate, completion rate and attrition rate) of the MBPE program. The secondary outcomes will be the preliminary effects of the MBPE program on symptoms of sarcopenia, motivation for PE, psychological well-being, mindfulness level, physical activity level and quality of life. Individual interviews will be conducted to identify the strengths, limitations and therapeutic components of the intervention. The quantitative data will be analysed by generalised estimating equations. The qualitative data will be analysed by Braun and Clarke's thematic approach.

CONCLUSION

The findings of this study will be able to provide evidence for the health professionals in adopting MBPE as a supportive intervention for the older adults with sarcopenia and the groundworks for the researchers in developing non-pharmacological intervention for older adults. The positive effects could facilitate healthy ageing and relief the burden of the medical system, especially in the countries facing the ageing population.

TRIAL REGISTRATION NUMBER

NCT05982067; ClinicalTrials.gov.

Impact of a Discontinuous Training Program on Sedentary Behavior in Italian Type 2 Diabetes Older Patients: The Results of the TRIPL-A Randomized Controlled Trial

Background: Physical activity is an important predictor of quality of life in older adults with type 2 diabetes (T2D). Unfortunately, most T2D adults adopt a sedentary lifestyle. The randomized, controlled TRIPL-A trial aims to verify the effect of a personalized, discontinuous exercise program on a sedentary lifestyle of T2D older adults. Methods: A total of 305 T2D patients (mean age ± SD: 68.8 ± 3.3 years) were divided into a control arm receiving only behavioral counseling and an intervention arm of an 18-month supervised discontinuous exercise program (ERS). The primary outcomes were the changes in sitting time (ST) and metabolic equivalent (MET) values, both evaluated by the International Physical Activity Questionnaire short form. A repeated measures ANOVA with Bonferroni correction for multiple comparisons was used to compare study outcomes. Results: The ST and MET differed significantly during the study compared to the control group (p = 0.028 and p = 0.004, respectively). In the intervention group, a decrease from baseline in ST at 6 months (p = 0.01) and an increase in MET values at 6 months (p = 0.01) up to 12 months (p < 0.01) were found. No significant differences were found for the other variables. Conclusions: Beneficial lifestyle changes were found within the first year of intervention. These results align with the theory of change.

Brisk walking improves motor function and lower limb muscle strength in Chinese women aged 80 years and older

This study investigates the effects of a 12-week brisk walking exercise regimen on motor function improvements in elderly women. Twenty-six elderly women, aged 84.2 ± 3.2 years, participated in a 12-week brisk walking exercise program. Fitness assessments and blood biomarker analyses (including CHO, HDLC, LDLC, TC) were conducted pre- and post-intervention. Additionally, targeted metabolomics was employed to measure short-chain fatty acids, amino acids, and vitamin metabolites. The intervention led to significant enhancements in participants' flexibility (p < 0.05), lower limb muscle strength (p < 0.01), and cardiorespiratory endurance (p < 0.01), while muscle mass showed no significant changes. Fifteen significant differential metabolites were identified (VIP > 1.0, FC > 1.2 or < 0.8, and p < 0.05), with arginine, ornithine, aspartic acid, glutamine, phenylalanine, tyrosine, and pantothenic acid playing key roles across seven metabolic pathways. A 12-week brisk walking exercise program significantly enhanced flexibility, lower limb muscle strength, and cardiorespiratory endurance among elderly women. These improvements did not extend to muscle mass or upper limb muscle strength. The observed enhancement in exercise capacity may be attributed to improved regulation of neurotransmitters.

Stroke related sarcopenia in individuals with different physical activity levels: A cross-sectional study

BACKGROUND AND OBJECTIVE

Individuals after stroke are likely to deal with the possible development of sarcopenia and reduced physical activity levels. The purpose of this study was to compare sarcopenia of individuals with chronic stroke who were stratified according to their physical activity levels, and to evaluate the relationship between sarcopenia and physical activity levels.

MATERIALS AND METHODS

This cross-sectional study was conducted with individuals after chronic stroke recruited from the general community. Individuals were submitted to sarcopenia screening (SARC-F questionnaire) and assessment of physical activity levels (Human Activity Profile questionnaire) to classify the individuals as impaired, moderately active, and active according to their Adjusted Activity Status (AAS). ANOVA was used to investigate the sarcopenia between groups and Pearson's coefficient to investigate the association among variables.

RESULTS

Fifty-four individuals with a mean age of 56 ± 17.4 years were included. Twenty-one percent of the individuals were screened for sarcopenia. Inactive individuals had higher mean scores in the SARC-F (3.6 ± 2.1 points), whereas moderately active and active individuals presented lower mean scores in the same questionnaire, being 1.2 ± 1.1 points and 0.5 ± 0.7 points, respectively. A statistically significant inverse and high association was found between sarcopenia and physical activity levels (r = -0.716; p < 0.01).

CONCLUSION

Sarcopenia was found to be higher in individuals after chronic stroke with lower physical activity levels considered inactive when compared to individuals with higher physical activity levels. Furthermore, there was an inverse relationship between sarcopenia and physical activity level in stroke survivors.

Skeletal Muscle Energetics Explain the Sex Disparity in Mobility Impairment in the Study of Muscle, Mobility and Aging

The age-related decline in muscle mitochondrial energetics contributes to the loss of mobility in older adults. Women experience a higher prevalence of mobility impairment compared to men, but it is unknown whether sex-specific differences in muscle energetics underlie this disparity. In the Study of Muscle, Mobility and Aging (SOMMA), muscle energetics were characterized using in vivo phosphorus-31 magnetic resonance spectroscopy and high-resolution respirometry of vastus lateralis biopsies in 773 participants (56.4% women, age 70-94 years). A Short Physical Performance Battery (SPPB) score ≤8 was used to define lower-extremity mobility impairment. Muscle mitochondrial energetics were lower in women compared to men (eg, Maximal Complex I&II OXPHOS: Women = 55.06 ± 15.95; Men = 65.80 ± 19.74; p < .001) and in individuals with mobility impairment compared to those without (eg, Maximal Complex I&II OXPHOS in women: SPPB ≥ 9 = 56.59 ± 16.22; SPPB ≤ 8 = 47.37 ± 11.85; p < .001). Muscle energetics were negatively associated with age only in men (eg, Maximal ETS capacity: R = -0.15, p = .02; age/sex interaction, p = .04), resulting in muscle energetics measures that were significantly lower in women than men in the 70-79 age group but not the 80+ age group. Similarly, the odds of mobility impairment were greater in women than men only in the 70-79 age group (70-79 age group, odds ratio [OR]age-adjusted = 1.78, 95% confidence interval [CI] = 1.03, 3.08, p = .038; 80+ age group, ORage-adjusted = 1.05, 95% CI = 0.52, 2.15, p = .89). Accounting for muscle energetics attenuated up to 75% of the greater odds of mobility impairment in women. Women had lower muscle mitochondrial energetics compared to men, which largely explain their greater odds of lower-extremity mobility impairment.

Imaging of Sarcopenia in Type 2 Diabetes Mellitus

Sarcopenia is an age-related condition characterized by the loss of skeletal muscle mass, muscular strength, and muscle function. In older adults, type 2 diabetes mellitus (T2DM) constitutes a significant health burden. Skeletal muscle damage and deterioration have emerged as novel chronic complications in patients with diabetes, often linked to their increased longevity. Diabetic sarcopenia has been associated with increased rates of hospitalization, cardiovascular events, and mortality. Nevertheless, effectively managing metabolic disorders in patients with T2DM through appropriate therapeutic interventions could potentially mitigate the risk of sarcopenia. Utilizing imaging technologies holds substantial clinical significance in the early detection of skeletal muscle mass alterations associated with sarcopenia. Such detection is pivotal for arresting disease progression and preserving patients' quality of life. These imaging modalities offer reproducible and consistent patterns over time, as they all provide varying degrees of quantitative data. This review primarily delves into the application of dual-energy X-ray absorptiometry, computed tomography, magnetic resonance imaging, and ultrasound for both qualitative and quantitative assessments of muscle mass in patients with T2DM. It also juxtaposes the merits and limitations of these four techniques. By understanding the nuances of each method, clinicians can discern how best to apply them in diverse clinical scenarios.

Effects of Physical Activity on Body Composition, Muscle Strength, and Physical Function in Old Age: Bibliometric and Meta-Analyses

OBJECTIVES

Accumulating evidence suggests that physical activity (PA) is an efficient intervention to maintain functional capabilities and mitigate physiological changes in the older population. However, an attempt has yet to be made to comprehensively investigate the published landscape on the subject.

METHODS

This study had two aims. The first aim was to perform a bibliometric analysis for two keywords, "aging" and "PA", to analyze the research trend. Since "frailty" was the most noticeable co-occurring keyword with the two keywords, the second aim was to investigate the effects of PA, particularly, resistance training (RT), on frailty using a meta-analysis to provide a summary of the current evidence base.

RESULTS

The bibliometric analysis revealed that the number of publications on this research topic has gradually increased, highlighting the importance of understanding the role of PA in aging. The meta-analysis found that RT had significant beneficial effects on physical frailty factors, including handgrip strength, lower limb strength, balance, gait speed, and stair-climbing ability.

CONCLUSION

These findings demonstrate that RT is an effective intervention for improving physical function in frail populations; thus, it has important implications for the development of PA programs for older adults with frailty. Future research is warranted to explore the optimal dose, frequency, and duration of RT programs for older adults, as well as the potential benefits of combining RT with other forms of PA, such as aerobic or balance exercises.

Types, functions and mechanisms of robot-assisted intervention for fall prevention: A systematic scoping review

BACKGROUND

Any individual may experience accidental falls, particularly older adults. Although robots can prevent falls, knowledge of their fall-preventive use is limited.

OBJECTIVE

To explore the types, functions, and mechanisms of robot-assisted intervention for fall prevention.

METHODS

A systematic scoping review of global literature published from inception to January 2022 was conducted according to Arksey and O'Malley's five-step framework. Nine electronic databases, namely, PubMed, Embase, CINAHL, IEEE Xplore, the Cochrane Library, Scopus, Web of Science, PsycINFO, and ProQuest, were searched.

RESULTS

Seventy-one articles were found with developmental (n = 63), pilot (n = 4), survey (n = 3), and proof-of-concept (n = 1) designs across 14 countries. Six types of robot-assisted intervention were found, namely cane robots, walkers, wearables, prosthetics, exoskeletons, rollators, and other miscellaneous. Five main functions were observed including (i) detection of user fall, (ii) estimation of user state, (iii) estimation of user motion, (iv) estimation of user intentional direction, and (v) detection of user balance loss. Two categories of mechanisms of robots were found. The first category was executing initiation of incipient fall prevention such as modeling, measurement of user-robot distance, estimation of center of gravity, estimation and detection of user state, estimation of user intentional direction, and measurement of angle. The second category was achieving actualization of incipient fall prevention such as adjust optimal posture, automated braking, physical support, provision of assistive force, reposition, and control of bending angle.

CONCLUSIONS

Existing literature regarding robot-assisted intervention for fall prevention is in its infancy. Therefore, future research is required to assess its feasibility and effectiveness.

Health and sociodemographic factors associated with low muscle strength, muscle mass, and physical performance among people living with HIV

ABSTRACTThis study examined the factors associated with low muscle strength, muscle mass, and physical performance in 331 people living with HIV. Participants completed handgrip as a strength measure, appendicular skeletal muscle mass using bioimpedance analysis, and chair rise was a physical performance measure. Multivariate logistic regression was used to analyze the association between low values on these measures with sociodemographic, HIV-related factors, and comorbidities. Higher body mass index (BMI) (OR = 0.91; CI = 0.86-0.97) and higher CD4/CD8 ratio (OR = 0.38; 95% CI = 0.18-0.82) were associated with decreased likelihood of low handgrip strength. Being non-employed (OR = 2.08; 95% CI = 1.07-4.06), having hypertension (OR = 2.27; 95% CI = 1.13-4.54) and rheumatism (OR = 5.46; 95% CI = 1.68-17.74) increased the chance of low handgrip strength. Higher BMI (OR = 0.43; 95% CI = 0.34-0.56), CD4/CD8 ratio (OR = 0.29; 95% CI = 0.09-0.93), and bioimpedance phase angle (OR = 0.22; 95% CI = 0.12-0.40) were associated with decreased likelihood of low muscle mass. Lastly, having less than eight years of education (OR = 1.87; 95% CI = 1.02-3.41) and being non-employed (OR = 8.18; 95% CI = 3.09-21.61) increased the chance of low chair stand performance. In addition, higher CD4 + lymphocytes count (OR = 0.99; 95% CI = 0.99-0.99) was associated with a decreased likelihood of low chair stand performance. In conclusion, specific and non-specific HIV-related factors are associated with low handgrip strength, low muscle mass, and/or low chair stand performance.

Clinical Risk Factors of Perioperative Pressure Injury in Older Adult Patients with a Hip Fracture

OBJECTIVE

To examine the clinical risk factors of perioperative pressure injury (PrI) in older adults with a hip fracture, including preoperative chronic comorbidities and postoperative complications.

METHODS

In this retrospective study, the authors queried the PearlDiver Patient Records database between January 2011 and January 2020. Data from 54,194 patients without preexisting PrI were included for analyses. Patients were separated into two groups: (1) one or more perioperative PrI and (2) no PrI. Clinical factors as outcome variables include 21 comorbidities and 10 complications.

RESULTS

Univariate analyses were computed to compare the variables between groups, and two logistic regression models were developed to find comorbidity predictors and complication predictors. Of all patients, 1,362 (2.5%) developed one or more perioperative PrI. Patients with perioperative PrIs were more likely to be older men. One-year mortality for patients with perioperative PrI was 2.5 times that of patients without PrI. The regression models showed that predictors of perioperative PrI are malnutrition, hypoalbuminemia, frailty, peripheral vascular disease, dementia, urinary tract infection, perioperative red blood cell transfusion, and atrial fibrillation.

CONCLUSIONS

Screening for these comorbidities and complications may assist in determining the risk of PrI in older adults undergoing hip fracture surgery. Determining PrI risk enables the appropriate prevention strategies to be applied perioperatively.

Skeletal muscle energetics explain the sex disparity in mobility impairment in the Study of Muscle, Mobility and Aging (SOMMA)

The age-related decline in muscle mitochondrial energetics contributes to the loss of mobility in older adults. Women experience a higher prevalence of mobility impairment compared to men, but it is unknown whether sex-specific differences in muscle energetics underlie this disparity. In the Study of Muscle, Mobility and Aging (SOMMA), muscle energetics were characterized using in vivo phosphorus-31 magnetic resonance spectroscopy and high-resolution respirometry of vastus lateralis biopsies in 773 participants (56.4% women, age 70-94 years). A Short Physical Performance Battery score ≤ 8 was used to define lower-extremity mobility impairment. Muscle mitochondrial energetics were lower in women compared to men (e.g. Maximal Complex I&II OXPHOS: Women=55.06 +/- 15.95; Men=65.80 +/- 19.74; p<0.001) and in individuals with mobility impairment compared to those without (e.g., Maximal Complex I&II OXPHOS in women: SPPB≥9=56.59 +/- 16.22; SPPB≤8=47.37 +/- 11.85; p<0.001). Muscle energetics were negatively associated with age only in men (e.g., Maximal ETS capacity: R=-0.15, p=0.02; age/sex interaction, p=0.04), resulting in muscle energetics measures that were significantly lower in women than men in the 70-79 age group but not the 80+ age group. Similarly, the odds of mobility impairment were greater in women than men only in the 70-79 age group (70-79 age group, OR age-adjusted =1.78, 95% CI=1.03, 3.08, p=0.038; 80+ age group, OR age-adjusted =1.05, 95% CI=0.52, 2.15, p=0.89). Accounting for muscle energetics attenuated up to 75% of the greater odds of mobility impairment in women. Women had lower muscle mitochondrial energetics compared to men, which largely explain their greater odds of lower-extremity mobility impairment.

Insulin Glargine is More Suitable Than Exenatide in Preventing Muscle Loss in Non-Obese Type 2 Diabetic Patients with NAFLD

AIM

This study investigated the effects of insulin glargine and exenatide on the muscle mass of patients with newly diagnosed type 2 diabetes (T2DM) and nonalcoholic fatty liver disease (NAFLD).

METHODS

We performed a post-hoc analysis of our previously study, a 24-week randomized controlled multicenter clinical trial (ClinicalTrials.gov, NCT02303730). Seventy-six patients were randomly assigned 1:1 to receive insulin glargine or exenatide treatment. The changes in psoas muscle area (PMA) (mm2) were obtained with the cross-sectional Dixonfat magnetic resonance images at the fourth lumber vertebra.

RESULTS

There were no significant differences in age, BMI, gender, and PMA in insulin glargine and exenatide groups at baseline. After treatment, PMA tended to increase by 13.13 (-215.52, 280.80) mm2 in the insulin glargine group and decrease by 149.09 (322.90-56.39) mm2 in the exenatide group (both p>0.05). Subgroup analysis showed a 560.64 (77.88, 1043.40) (mm2) increase of PMA in the insulin group relative to the Exenatide group in patients with BMI<28 kg/m2 (p0.031) after adjusting for gender, age, and research center. Interaction analysis showed an interaction between BMI and treatment (p0.009). However, no interaction was observed among subgroups with a BMI≥28 kg/m2 or with different genders and ages.

CONCLUSION

Compared to exenatide, insulin glargine can relativity increase PMA in patients with T2DM having BMI<28 kg/m2 and NAFLD.

Measures of perceived mobility ability in community-dwelling older adults: a systematic review of psychometric properties

OBJECTIVES

The objective of this systematic review was to synthesise the psychometric properties of measures of perceived mobility ability and related frameworks used to define and operationalise mobility in community-dwelling older adults.

METHODS

We registered the review protocol with PROSPERO (CRD42022306689) and included studies that examined the psychometric properties of perceived mobility measures in community-dwelling older adults. Five databases were searched to identify potentially relevant primary studies. We qualitatively summarised psychometric property estimates and related operational frameworks. We conducted risk of bias and overall quality assessments, and meta-analyses when at least three studies were included for a particular outcome. The synthesised results were compared against the Consensus-based Standards for the Selection of Health Measurement Instruments criteria for good measurement properties.

RESULTS

A total of 36 studies and 17 measures were included in the review. The Late-Life Function and Disability Index: function component (LLFDI-FC), lower extremity functional scale (LEFS), Mobility Assessment Tool (MAT)-short form (MAT-SF) or MAT-Walking, and Perceived Driving Abilities (PDA) Scale were identified with three or more eligible studies. Most measures showed sufficient test-retest reliability (moderate or high), while the PDA scale showed insufficient reliability (low). Most measures had sufficient or inconsistent convergent validity (low or moderate) or known-groups validity (low or very low), but their predictive validity and responsiveness were insufficient or inconsistent (low or very low). Few studies used a conceptual model.

CONCLUSION

The LLFDI-FC, LEFS, PDA and MAT-SF/Walking can be used in community-dwelling older adults by considering the summarised psychometric properties. No available comprehensive mobility measure was identified that covered all mobility domains.

Machine Learning Models to Predict Future Frailty in Community-Dwelling Middle-Aged and Older Adults: The ELSA Cohort Study

BACKGROUND

Machine learning (ML) models can be used to predict future frailty in the community setting. However, outcome variables for epidemiologic data sets such as frailty usually have an imbalance between categories, that is, there are far fewer individuals classified as frail than as nonfrail, adversely affecting the performance of ML models when predicting the syndrome.

METHODS

A retrospective cohort study with participants (50 years or older) from the English Longitudinal Study of Ageing who were nonfrail at baseline (2008-2009) and reassessed for the frailty phenotype at 4-year follow-up (2012-2013). Social, clinical, and psychosocial baseline predictors were selected to predict frailty at follow-up in ML models (Logistic Regression, Random Forest [RF], Support Vector Machine, Neural Network, K-nearest neighbor, and Naive Bayes classifier).

RESULTS

Of all the 4 378 nonfrail participants at baseline, 347 became frail at follow-up. The proposed combined oversampling and undersampling method to adjust imbalanced data improved the performance of the models, and RF had the best performance, with areas under the receiver-operating characteristic curve and the precision-recall curve of 0.92 and 0.97, respectively, specificity of 0.83, sensitivity of 0.88, and balanced accuracy of 85.5% for balanced data. Age, chair-rise test, household wealth, balance problems, and self-rated health were the most important frailty predictors in most of the models trained with balanced data.

CONCLUSIONS

ML proved useful in identifying individuals who became frail over time, and this result was made possible by balancing the data set. This study highlighted factors that may be useful in the early detection of frailty.

Effectiveness of elastic band training and group-based dance on physical-functional performance in older women with sarcopenia: a pilot study

BACKGROUND

Sarcopenia is a syndrome associated with aging that causes progressive loss of skeletal muscle mass and muscle function. In this pilot study, we compared the effectiveness of elastic band training regarding group-based dance on fat mass, fat-free mass, handgrip strength (HGS; dominant and non-dominant hand), leg strength, timed up-and-go (TUG) and walking speed in older women with sarcopenia.

METHODS

This is a randomized controlled trial, single-blind, repeated measures of parallel groups (elastic band group: EBG, n = 21; group-based dance: GBD, n = 19), and a quantitative methodology. Three 60-minute sessions per week for 12 weeks were dedicated to the interventions with pre- and post-assessments. A two-factor mixed analysis of variance (ANOVA) model with repeated measures was performed to measure the group×time effect.

RESULTS

A significant interaction revealed for fat-free mass (F1,16= 18.91; p < 0.001; EBG + 10.9% vs. GBD - 1.97%), HGS dominant hand (F1,16= 7.44; p = 0.014; EBG + 10.9% vs. GBD + 0.59%), HGS non-dominant hand (F1,16= 6.41; p = 0.022; EBG + 10.21% vs. GBD + 3.80%), leg strength (F1,16= 17.98; p < 0.001; EBG + 9.1% vs. GBD + 3.83%), TUG (F1,16= 7.52; p = 0.014; EBG - 14.7% vs. GBD - 1.0%) and walking speed (F1,16 = 6.40; p = 0.019; EBG - 7.6% vs. GBD - 4.35%) in favor of EBG.

CONCLUSION

Elastic band training produces significantly greater responses on physical-functional performance regarding group-based dance in older women with sarcopenia. On the other hand, the EBG revealed a significant improvement in fat-free mass and upper and lower limb muscle strength, as well as a significant decrease time in TUG, and walking speed. Elastic band exercise is a safe, easy, affordable, and effective physical activity strategy, according to the findings.

Are assessment measures for components of the International Classification of Functioning, Disability and Health reproducible for use on pre-frail and frail older adults? A systematic review

OBJECTIVE

To analyze the internal consistency, reliability and measurement error of assessment measures for body structure and function (postural balance, muscle strength, cardiorespiratory function and physical fitness), activity (walking and mobility) and participation (quality of life and social reintegration) outcomes for use on pre-frail and frail older adults.

METHODS

Searches were performed in six databases (Medline, Embase, ScienceDirect, Web of Science, The Cochrane Library and Lilacs) and reproducibility studies were included. Cronbach's alpha and the classification proposed by Terwee et al. (2007) were used for the interpretation of internal consistency. The intraclass correlation coefficient (ICC) and the Munro classification were used for the determination of reliability. The standard error of measurement (SEM), minimal detectable change (MDC) as well as percentages of error (SEM%) and change (MDC%) were calculated. Methodological quality of the studies was appraised using Boxes 4, 6 and 7 of the COSMIN Risk of Bias checklist.

RESULTS

Six studies were included in the present systematic review, with a total of 835 (82.4 years; 582 women and 253 men) pre-frail and frail older adults analyzed. Seven measures were identified for the assessment of body structure and function, activity and participation outcomes (Hierarchical Assessment of Balance and Mobility, Self-Assessment of Physical Fitness, Sarcopenia Quality of Life, Reintegration to Normal Living Index, Two-Minute Walking test, Six-Minute Walking test and Ten-Meter Walking test). The following measurement properties were identified: internal consistency = 0.84 (mean Cronbach's alpha); reliability = 0.87 (mean ICC); SEM range = 0.06 to 10.10; MDC range = 0.13 to 28.10; SEM% range = 5.2 % to 9.5 %; and MDC% range = 10.7 % to 28.5 %.

CONCLUSION

The present systematic review found adequate internal consistency, high reliability and an acceptable measurement error for assessment measures of body structure and function, activity and participation outcomes for use on pre-frail and frail older adults.

Can Leucine Supplementation Improve Frailty Index Scores?

Sarcopenia and frailty are important conditions that become increasingly prevalent with age. There is partial overlap between the two conditions, especially in terms of the physical aspects of the frailty phenotype: low grip strength, gait speed, and muscle mass. This study examined whether administration of the essential branched-chain amino acid leucine, besides improving sarcopenia, may reduce frailty assessed by frailty index (FI) in older institutionalized people living in nursing homes. We conducted a secondary analysis of a placebo-controlled, randomized, double-blind design study (ClinicalTrials.gov NCT03831399). The study included fifty males and females aged 65 and over who were living in nursing homes and did not have dementia. The participants were randomized to a parallel group intervention of 13 weeks' duration, with a daily intake of leucine (6 g/day) or placebo (lactose, 6 g/day). The outcome of this study was to evaluate whether there was a change in the level of a 95 item FI compared to the baseline and to compare the effect of the leucine group versus the placebo group. A significant inverse correlation was found between FI and performance of the activities of daily life, cognitive function, gait and balance, muscle function parameters, and nutritional status (p < 0.001 in all cases). There were no statistically significant differences in FI levels at baseline (placebo group FI 0.27 ± 0.08 and leucine group FI 0.27 ± 0.10) and at the 13 week follow-up (placebo group FI 0.28 ± 0.10 and leucine group FI 0.28 ± 0.09). There were also no significant differences between the leucine and placebo groups in the mean FI difference between baseline and follow-up (p = 0.316, Cohen's d: 0.04). This pilot study showed that a nutritional supplementation with leucine did not significantly modify the frailty index in older nursing home residents.

Sarcopenia, a condition shared by various diseases: can we alleviate or delay the progression?

Sarcopenia is a severe condition common to various chronic diseases and it is reckoned as a major health problem. It encompasses many different molecular mechanisms that have been for a while discovered but not definitely clarified. Although sarcopenia is a disability status that leads to serious health consequences, the scarcity of suitable animal models has curtailed research addressing this disorder. Another limitation in the field of clinical investigation of sarcopenic patients is the lack of a generally accepted definition coupled with the difficulty of adopting common diagnostic criteria. In fact, both do not permit to clarify the exact prevalence rate and consequently limit physicians to establish any kind of therapeutical approach or, when possible, to adopt preventive measures. Unfortunately, there is no standardized cure, apart from doing more physical activity and embracing a balanced diet, but newly discovered substances start being considered. In this review, authors try to give an overview addressing principal pathways of sarcopenia and offer critical features of various possible interventions.

Oat β-glucan alleviates muscle atrophy via promoting myotube formation and suppressing protein degradation

BACKGROUND

The dangerous inducers of muscle atrophy are inflammatory reaction, oxidative stress, and cachexia, etc. β-Glucan, an important food derived active ingredient, has been reported to exert anti-inflammatory effects, however, its effects on regulating myoblast differentiation and protein degradation are unclear. This study is aimed to investigate the mechanism of oat β-glucan on alleviating muscle atrophy.

RESULTS

The results showed that oat β-glucan treatment reversed tumor necrosis factor-α (TNF-α) induced abnormal myoblast differentiation and reduced muscle atrophy related MuRF-1 and Atrogin-1 protein expression. The similar phenomenon was observed after using MCC950 (NLRP3 specific inhibitor) or AS1842856 (FoxO1 specific inhibitor) to suppress NLRP3 and FoxO1 expression, respectively. Exposure to β-glucan or AS1842856 also inhibited TNF-α induced the activation of TLR4/NF-κB pathway by inactivating FoxO1, and subsequently suppressed the expression of NLRP3.

CONCLUSION

Our results indicate that oat β-glucan exerts essential roles in promoting myoblast differentiation and alleviating muscle atrophy via inactivating FoxO1 and NLRP3 inflammasome signal pathway. © 2023 Society of Chemical Industry.

Anabolic Resistance in the Pathogenesis of Sarcopenia in the Elderly: Role of Nutrition and Exercise in Young and Old People

The development of sarcopenia in the elderly is associated with many potential factors and/or processes that impair the renovation and maintenance of skeletal muscle mass and strength as ageing progresses. Among them, a defect by skeletal muscle to respond to anabolic stimuli is to be considered. Common anabolic stimuli/signals in skeletal muscle are hormones (insulin, growth hormones, IGF-1, androgens, and β-agonists such epinephrine), substrates (amino acids such as protein precursors on top, but also glucose and fat, as source of energy), metabolites (such as β-agonists and HMB), various biochemical/intracellular mediators), physical exercise, neurogenic and immune-modulating factors, etc. Each of them may exhibit a reduced effect upon skeletal muscle in ageing. In this article, we overview the role of anabolic signals on muscle metabolism, as well as currently available evidence of resistance, at the skeletal muscle level, to anabolic factors, from both in vitro and in vivo studies. Some indications on how to augment the effects of anabolic signals on skeletal muscle are provided.

Virtual reality exercise programs ameliorate frailty and fall risks in older adults: A meta-analysis

BACKGROUND

Virtual reality (VR) technology constitutes a promising rehabilitation strategy, but its effect on frailty in older adults remains inconclusive. This study examined the effects of interactive VR training programs on lower-limb muscle strength, walking speed, balance, and fall risks in older adults with frailty.

METHODS

Various electronic databases comprising PubMed, the Cumulative Index to Nursing and Allied Health Literature, the Cochrane Library, Embase, the Chinese Electronic Periodical Service, the Chinese National Knowledge Infrastructure, and gray literature were searched from their inception through December 31, 2022 for relevant studies. Randomized controlled trials that examined the effects of interactive VR training programs on lower-limb muscle strength, balance, walking speed, and fall risks as measured by validated scales or methods. in older adults aged 65 years and older with frailty were included. A random-effects model was employed to examine the overall effect size, and the trim-and-fill method was adopted to examine publication bias.

RESULTS

For those studies that defined frailty using fall risks, substantial evidence demonstrated that interactive VR training interventions increased lower-limb muscle strength (Hedges' g = 0.35, p = 0.015), walking speed (Hedges' g = 0.29, p = 0.003), balance (Hedges' g = 0.62, p = 0.011), and fall risks (Hedges' g = -0.61, p < 0.001). Studies that defined frailty in accordance with the Fried frailty phenotype criteria indicated that interactive VR training interventions only increased walking speed (Hedges' g = 0.28, p = 0.023) and balance (Hedges' g = 0.27, p = 0.049).

CONCLUSIONS

Interactive VR training programs may benefit older adults with frailty with respect to walking speed and balance. More studies with good study quality are required to validate the effects of interactive VR exercise training on these frailty-related parameters in older adults.