Handgrip Strength Is Associated With Hippocampal Volume and White Matter Hyperintensities in Major Depression and Healthy Controls: A UK Biobank Study

"Mind-Muscle Connections": Differential Associations Between Handgrip and Upper Body Strength With Cognitive Function in Young and Middle-Aged Adults

The relationship between muscle strength and cognition is widely studied in older adults; however, understanding this association at younger ages may help detect markers of early cognitive changes and inform future interventions. Accordingly, we aimed to identify relationships between handgrip, whole-body, upper body, and lower body strength and cognitive functions. A total of 112 adults (aged 18-50 years) completed comprehensive measures of muscle strength, aerobic capacity, body composition, and cognitive function. Hierarchical linear regressions revealed that individuals with stronger handgrip had better mental rotation performance (standardized β = 0.39); those with greater upper body strength had superior recognition (standardized β = 0.52) and pattern separation abilities (standardized β = 0.39), but whole- and lower body strength were not associated. Results demonstrate the unique relationship between upper body strength and aspects of cognitive function, in addition to differential associations of upper body and handgrip strength with encoding, retrieval, and spatial skills. The current findings establish an association between strength and cognitive function earlier than previously thought.

Association of sarcopenia with regional brain atrophy and white matter lesions in a general older population: the Hisayama Study

Sarcopenia has been reported to be associated with cognitive decline and the risk of dementia. However, few studies have addressed the association between sarcopenia and brain morphological changes in the general population. A total of 1373 community-dwelling participants aged ≥ 65 years underwent brain MRI. Sarcopenia was defined based on the Asian Working Group for Sarcopenia's criteria. The pattern of regional gray matter volume loss associated with sarcopenia were assessed using a voxel-based morphometry (VBM) analysis. Regional brain volumes, intracranial volumes (ICV), and white matter lesions volumes (WMLV) were also measured using FreeSurfer. An analysis of covariance was used to examine the associations of sarcopenia with regional brain volumes in proportion to ICV. Of the participants, 112 had sarcopenia. The participants with sarcopenia had significantly lower total brain volume/ICV and total gray matter volume/ICV and higher WMLV/ICV than those without sarcopenia after adjusting for confounders. In VBM, sarcopenia was associated with lower gray matter volume in the frontal lobe, insula, cingulate gyrus, hippocampus, amygdala, and basal ganglia. Using FreeSurfer, we confirmed that the participants with sarcopenia had significantly lower frontal, insular, cingulate, and hippocampal volumes than those without sarcopenia. The current study showed that participants with sarcopenia had significantly lower volume in the frontal lobe, insula, cingulate, and hippocampus and higher WMLV than participants without sarcopenia. As these brain regions are likely to play an important role in cognitive function, these changes may suggest a shared underlying mechanism for the progression of sarcopenia and cognitive decline.

Low hand grip strength as an indicator of depression in the Korean population: a large-scale cross-sectional study

Background

Depression is one of the leading global mental health problems, and hand grip strength (HGS) is associated with depression. However, there have been no studies assessing the association between depression and relative HGS indices combined with waist circumference (WC) and the waist-to-height ratio (WHtR). The objective of this study was to examine the association of depression with absolute and relative HGS indices.

Methods

This was a cross-sectional study based on the Korea National Health and Nutrition Examination Survey from 2014 to 2019. A total of 20,649 participants (8,959 men, 43.4% and 11,690 women, 56.6%) were included. The associations between depression and the HGS indices were analyzed through complex sample binary logistic regression models, which were adjusted for age in Model 1 and various covariates in Model 2.

Results

The prevalence of depression was 4.58%, with rates of 2.29% for men and 6.34% for women. The prevalence of depression in women was 2.76 times greater than that in men. In men, the mean HGS values in the dominant hand were 35.48 ± 0.75 kg in the depression group and 38.73 ± 0.11 kg in the non-depression group; in women, they were 21.37 ± 0.22 kg in the depression group and 22.77 ± 0.07 kg in the non-depression group. In men, relative HGS indices as HGS/WC, HGS/body mass index, and HGS/WHtR were more strongly associated with depression than were the absolute HGS indices; however, in women, the associations were similar for both absolute and relative HGS indices. The magnitude of the association was greater for men than for women. In both sexes, all the anthropometric indices had a lower association with depression than did the HGS indices.

Conclusion

Low absolute and relative HGS were negatively associated with depression in the Korean population. But, relative HGS indices were more strongly associated with depression than were absolute HGS and anthropometric indices in men but not in women.

Pulse pressure is associated with decline in physical function in older adults

OBJECTIVES

This study examined the associations between pulse pressure, hypertension, and the decline in physical function in a prospective framework.

STUDY DESIGN

The Healthy Aging Longitudinal Study tracked a group of Taiwanese adults aged 55 or more over an average of 6.19 years to assess pulse pressure and decline in physical function, including in handgrip strength, gait speed, and 6-min walking distance, at baseline (2009-2013) and in the second phase of assessments (2013-2020).

MAIN OUTCOME MEASURES

Pulse pressure was calculated as the difference between systolic and diastolic blood pressure values. Weakness, slowness, and low endurance were defined as decreases of ≥0.23 m/s (one standard deviation) in gait speed, ≥5.08 kg in handgrip strength, and ≥ 57.73 m in a 6-min walk, as determined from baseline to the second phase of assessment. Linear and logistic regressions were employed to evaluate the associations between pulse pressure, hypertension, and decline in physical function.

RESULTS

Baseline pulse pressure was associated with future handgrip strength (beta = -0.017, p = 0.0362), gait speed (beta = -0.001, p < 0.0001), and 6-min walking distance (beta = -0.470, p < 0001). In multivariable models, only handgrip strength (beta = -0.016, p = 0.0135) and walking speed (beta = -0.001, p = 0.0042) remained significantly associated with future pulse pressure. Older adults with high systolic blood pressure (≥140 mmHg) and elevated pulse pressure (≥60 mmHg) exhibited a significantly increased risk of weakness (odds ratio: 1.30, 95 % confidence interval: 1.08-1.58), slowness (1.29, 1.04-1.59), and diminished endurance (1.25, 1.04-1.50) compared with the reference group, who exhibited systolic blood pressure of <140 mmHg and pulse pressure of <60 mmHg.

CONCLUSIONS

Among older adults, pulse pressure is associated with a decline in physical function, especially in terms of strength and locomotion.

Development of a prediction model for cognitive impairment of sarcopenia using multimodal neuroimaging in non-demented older adults

INTRODUCTION

Despite prior research on the association between sarcopenia and cognitive impairment in the elderly, a comprehensive model that integrates various brain pathologies is still lacking.

METHODS

We used data from 528 non-demented older adults with or without sarcopenia in the Catholic Aging Brain Imaging (CABI) database, containing magnetic resonance imaging scans, positron emission tomography scans, and clinical data. We also measured three key components of sarcopenia: skeletal muscle index (SMI), hand grip strength (HGS), and the five times sit-to-stand test (5STS).

RESULTS

All components of sarcopenia were significantly correlated with global cognitive function, but cortical thickness and amyloid-beta (Aβ) retention had distinctive relationships with each measure. In the path model, brain atrophy resulting in cognitive impairment was mediated by Aβ retention for SMI and periventricular white matter hyperintensity for HGS, but directly affected by the 5STS.

DISCUSSION

Treatments targeting each sub-domain of sarcopenia should be considered to prevent cognitive decline.

HIGHLIGHTS

We identified distinct impacts of three sarcopenia measures on brain structure and Aβ. Muscle mass is mainly associated with Aβ and has an influence on the brain atrophy. Muscle strength linked with periventricular WMH and brain atrophy. Muscle function associated with cortical thinning in specific brain regions. Interventions on sarcopenia may be important to ease cognitive decline in the elderly.

Cardiorespiratory fitness mediates the relationship between depressive symptomatology and cognition in older but not younger adults

Aging is commonly associated with emotional, physical, and cognitive changes, with the latter, particularly affecting executive functioning. Further, such changes may interact. For instance, depressive symptomatology is a known risk factor for developing cognitive deficits, especially at older ages. In contrast, an active lifestyle, reflected in high cardiorespiratory fitness (CRF) levels, has proven to protect against adverse effects on cognition across the adult lifespan. Hence, this study aimed to investigate the relationships between depressive symptomatology, CRF, and cognition during critical developmental stages, namely in young adults (YA), when cognitive abilities are at their peak, and in older adults (OA), when they may start to decline. Eighty-one OA with ages between 60 and 89 years (M = 70.46; SD = 7.18) and 77 YA with ages between 18 and 34 years (M = 22.54; SD = 3.72) went through (i) a sociodemographic interview, (ii) an emotional assessment, (iii) a battery of cognitive tests, and (iv) a physical evaluation assessing CRF levels, visceral fat and body-mass index. Results showed that OA exhibited lower general cognitive performance, inhibitory control, cognitive flexibility, memory, and CRF. Depressive symptoms and anxiety were not different among groups, with CRF mediating the relationship between depressive symptoms and cognition in the OA group. The present study provides valuable insights into the interplay between emotional, physical, and cognitive well-being. Additionally, it calls attention to how lifestyle factors can play a protective role against the adverse effects that depressive symptoms have on cognition, particularly at older ages.

Classification of Mild Cognitive Impairment and Alzheimer's Disease Using Manual Motor Measures

INTRODUCTION

Manual motor problems have been reported in mild cognitive impairment (MCI) and Alzheimer's disease (AD), but the specific aspects that are affected, their neuropathology, and potential value for classification modeling is unknown. The current study examined if multiple measures of motor strength, dexterity, and speed are affected in MCI and AD, related to AD biomarkers, and are able to classify MCI or AD.

METHODS

Fifty-three cognitively normal (CN), 33 amnestic MCI, and 28 AD subjects completed five manual motor measures: grip force, Trail Making Test A, spiral tracing, finger tapping, and a simulated feeding task. Analyses included (1) group differences in manual performance; (2) associations between manual function and AD biomarkers (PET amyloid β, hippocampal volume, and APOE ε4 alleles); and (3) group classification accuracy of manual motor function using machine learning.

RESULTS

Amnestic MCI and AD subjects exhibited slower psychomotor speed and AD subjects had weaker dominant hand grip strength than CN subjects. Performance on these measures was related to amyloid β deposition (both) and hippocampal volume (psychomotor speed only). Support vector classification well-discriminated control and AD subjects (area under the curve of 0.73 and 0.77, respectively) but poorly discriminated MCI from controls or AD.

CONCLUSION

Grip strength and spiral tracing appear preserved, while psychomotor speed is affected in amnestic MCI and AD. The association of motor performance with amyloid β deposition and atrophy could indicate that this is due to amyloid deposition in and atrophy of motor brain regions, which generally occurs later in the disease process. The promising discriminatory abilities of manual motor measures for AD emphasize their value alongside other cognitive and motor assessment outcomes in classification and prediction models, as well as potential enrichment of outcome variables in AD clinical trials.

The Grip Strength Loss Rate and the Subsequent Cognitive Decline Rate in Older Adults: The Moderating Role of Social Isolation

Background and Objectives

Accumulating evidence suggests that low grip strength (GS) is associated with a faster cognitive decline, but most previous studies have measured GS at a single time point, ignoring changes in GS. We aimed to explore the association of the GS loss rate with the sequent cognitive decline, as well as the moderating role of social isolation in older adults.

Research Design and Methods

Data were from the English Longitudinal Study of Ageing. Absolute and relative GS loss rates were calculated as the annual losses from Wave 2 (2004-05) to Wave 4 (2008-09). Participants were divided into 3 groups according to the tertiles of GS loss rates. Linear mixed models were used to assess the association of the GS loss rate during Waves 2-4 with the cognitive decline rate during Waves 4-9 (Wave 9, 2018-19).

Results

Of the 4 356 participants included in analyses, 1 938 (44.5%) were men, with a mean age of 68.4 (SD: 8.4) years. Compared with Tertile 1 of the absolute GS loss rate, Tertile 2 (β = -0.009 [95% CI: -0.018 to -0.001] SD/year) and Tertile 3 (β = -0.018 [95% CI: -0.027 to -0.010] SD/year) were associated with a faster cognitive decline rate. The results of relative GS were similar to those of absolute GS. Social isolation was a significant modifier in the associations of the absolute GS loss rate with decline rates in global cognition and episodic memory, but not in temporal orientation. We did not observe that social isolation moderated the association of the relative GS loss rate with the cognitive decline rate.

Discussion and Implications

Both absolute and relative GS loss rates were positively associated with the cognitive decline rate in older adults. Low social isolation scores attenuated the association of the absolute GS loss rate with the cognitive decline rate.

Handgrip strength is associated with cognitive function in older patients with stage 3-5 chronic kidney disease: results from the NHANES

In this study, we aimed to investigate the association between handgrip strength (HGS) and cognitive performance in stage 3-5 chronic kidney disease (CKD) patients aged ≥ 60 years. This cross-sectional study analyzed data from National Health and Nutrition Examination Survey (NHANES) database 2011-2014. Three tests were used to assess the cognitive performance, including consortium to establish a registry for Alzheimer's disease (CERAD), animal fluency test (AFT), and digit symbol substitution test (DSST). The multivariate linear regression analyses adjusting for confounding factors were utilized to evaluate the association of HGS with cognitive performance. A total of 678 older stage 3-5 CKD patients were included in this study. After adjusting for multiple factors, a higher HGS was positively associated with a higher CERAD-delayed recall and DSST score. In addition, our analysis indicated that HGS probably correlated with better performance of immediate learning ability in male, while working memory, sustained attention, and processing speed in female. HGS may be an important indicator for cognitive deficits in stage 3-5 CKD patients, especially for learning ability and executive function. Further research to explore the sex-specific and domain-specific and possible mechanisms are required.

Deficits in force production during multifinger tasks demarcate cognitive dysfunction

BACKGROUND

The multifinger force deficit (MFFD) is the decline in force generated by each finger as the number of fingers contributing to an action is increased. It has been shown to associate with cognitive status.

AIMS

The aim was to establish whether a particularly challenging form of multifinger grip dynamometry, that provides minimal tactile feedback via cutaneous receptors and requires active compensation for reaction forces, will yield an MFFD that is more sensitive to cognitive status.

METHODS

Associations between measures of motor function, and cognitive status (Montreal Cognitive Assessment [MoCA]) and latent components of cognitive function (derived from 11 tests using principal component analysis), were estimated cross-sectionally using generalized partial rank correlations. The participants (n  =  62) were community dwelling, aged 65-87.

RESULTS

Approximately half the participants were unable to complete the dynamometry task successfully. Cognitive status demarcated individuals who could perform the task from those who could not. Among those who complied with the task requirements, the MFFD was negatively correlated with MoCA scores-those with the highest MoCA scores tended to exhibit the smallest deficits, and vice versa. There were corresponding associations with latent components of cognitive function.

DISCUSSION

The results support the view that neurodegenerative processes that are a feature of normal and pathological aging exert corresponding effects on expressions of motor coordination-in multifinger tasks, and cognitive sufficiency, due to their dependence on shared neural systems.

CONCLUSIONS

The outcomes add weight to the assertion that deficits in force production during multifinger tasks are sensitive to cognitive dysfunction.

Uncovering Predictors of Low Hippocampal Volume: Evidence from a Large-Scale Machine-Learning-Based Study in the UK Biobank

INTRODUCTION

Hippocampal atrophy is an established biomarker for conversion from the normal ageing process to developing cognitive impairment and dementia. This study used a novel hypothesis-free machine-learning approach, to uncover potential risk factors of lower hippocampal volume using information from the world's largest brain imaging study.

METHODS

A combination of machine learning and conventional statistical methods were used to identify predictors of low hippocampal volume. We run gradient boosting decision tree modelling including 2,891 input features measured before magnetic resonance imaging assessments (median 9.2 years, range 4.2-13.8 years) using data from 42,152 dementia-free UK Biobank participants. Logistic regression analyses were run on 87 factors identified as important for prediction based on Shapley values. False discovery rate-adjusted p value <0.05 was used to declare statistical significance.

RESULTS

Older age, male sex, greater height, and whole-body fat-free mass were the main predictors of low hippocampal volume with the model also identifying associations with lung function and lifestyle factors including smoking, physical activity, and coffee intake (corrected p < 0.05 for all). Red blood cell count and several red blood cell indices such as haemoglobin concentration, mean corpuscular haemoglobin, mean corpuscular volume, mean reticulocyte volume, mean sphered cell volume, and red blood cell distribution width were among many biomarkers associated with low hippocampal volume.

CONCLUSION

Lifestyles, physical measures, and biomarkers may affect hippocampal volume, with many of the characteristics potentially reflecting oxygen supply to the brain. Further studies are required to establish causality and clinical relevance of these findings.

Size or Strength? how components of muscle relate to behavioral and neuroelectric measures of executive function independent of aerobic fitness

While previous research has linked cognitive function with resistance exercise, the nuanced links between muscle strength, mass, and neuroelectric function are less understood. Therefore, this study investigated the association of muscle strength and mass with inhibitory control (IC), working memory (WM), and related neuroelectric activity. A total of 123 18-50-year-old adults completed maximal aerobic capacity and strength tests, a body composition scan, and IC and WM tasks while the N2 and P3 components of event-related potentials were recorded. Bivariate correlations revealed aerobic fitness, strength, and mass were associated with behavioral and neuroelectric outcomes. After accounting for age, sex, and aerobic fitness, strength was associated with intra-individual response time variability, accuracy, and P3 latency during WM. Muscle mass was associated with N2 latency during IC. While relationships with behavioral outcomes did not persist after controlling for the opposite muscle outcome, greater strength and mass were related to shorter P3 latency during WM and shorter N2 latency during IC, respectively. These results provide initial evidence that muscle outcomes are associated with executive function and neuroelectric processing speed, suggesting distinct contributions of strength and mass to cognition. This work highlights the significance of maintaining muscle strength and mass alongside aerobic fitness for optimal cognitive health.

Can Muscular Parameters Predict Symptoms of Anxiety and Depression?

Major depressive disorder and anxiety disorders are among the major public health issues. Therefore, identifying predictors of symptoms of depression and anxiety holds fundamental importance to avoid the aggravation of these conditions. Muscle strength and function (e.g., handgrip strength and timed-stands test) are widely recognized predictors of health outcomes; however, their association with symptoms of depression and anxiety is still not completely understood. This study investigated the associations between handgrip strength and timed-stands test scores with symptoms of depression and anxiety. In addition, we examined whether individuals exhibiting greater strength levels demonstrate reduced symptoms of anxiety and depression compared to those with lower levels of strength. This is a community-based, cross-sectional study. Participants were recruited through social media and underwent a semi-structured interview to record sociodemographic characteristics, comorbidities, use of tobacco and medication, and symptoms of anxiety (Beck's Anxiety Inventory [BAI]) and depression (Beck's Depressive Inventory [BDI]). Subsequently, anthropometric characteristics, handgrip strength, and functionality (i.e., timed-stands test) were assessed. In all, 216 individuals were evaluated. The adjusted regression model showed an inverse association between handgrip strength and anxiety (β = -0.22; 95% CI [-0.38, -0.07]; R2 = 0.07, p = .005) and depression symptoms (β = -0.25; 95% CI [-0.42, -0.07]; R2 = 0.05, p = .006). Similarly, timed-stands test scores were associated with anxiety (β = -0.33; 95% CI [-0.54, -0.13]; R2 = 0.09, p = .002) and depression (β = -0.32; 95% CI [-0.56, -0.09]; R2 = 0.06, p = .008). Furthermore, the low-strength group showed higher values on the BAI (9.5 vs. 5.9 arbitrary units; p = .0008) and BDI than the high-strength group (10.8 vs. 7.9 arbitrary units; p = .0214). When individuals were stratified by the timed-stands test, the low timed-stands group demonstrated higher values on the BAI (9.9 vs. 5.5 arbitrary units; p = .0030) and BDI than the high timed-stands group (11.2 vs. 7.5 arbitrary units; p < .0001). The results highlight muscular parameters as significant predictors associated with anxiety and depression symptoms.

Bridging Reduced Grip Strength and Altered Executive Function: Specific Brain White Matter Structural Changes in Patients with Alzheimer's Disease

Objective

To investigate the correlation between specific fiber tracts and grip strength and cognitive function in patients with Alzheimer's disease (AD) by fixel-based analysis (FBA).

Methods

AD patients were divided into AD with low grip strength (AD-LGS, n=29) and AD without low grip strength (AD-nLGS, n=25), along with 31 normal controls (NC). General data, neuropsychological tests, grip strength and cranial magnetic resonance imaging (MRI) scans were collected. FBA evaluated white matter (WM) fiber metrics, including fiber density (FD), fiber cross-sectional (FC), and fiber density and cross-sectional area (FDC). The mean fiber indicators of the fiber tracts of interest (TOI) were extracted in cerebral region of significant statistical differences in FBA to further compare the differences between groups and analyze the correlation between fiber properties and neuropsychological test scores.

Results

Compared to AD-nLGS group, AD-LGS group showed significant reductions in FDC in several cerebral regions. In AD patients, FDC values of bilateral uncinate fasciculus and left superior longitudinal fasciculus were positively correlated with Clock Drawing Test scores, while FDC of splenium of corpus callosum, bilateral anterior cingulate tracts, forceps major, and bilateral inferior longitudinal fasciculus were positively correlated with the Executive Factor Score of Memory and Executive Screening scale scores.

Conclusion

Reduced grip strength in AD patients is associated with extensive impairment of WM structural integrity. Changes in FDC of specific WM fiber tracts related to executive function play a significant mediating role in the reduction of grip strength in AD patients.

Loneliness is related to smaller gray matter volumes in ACC and right VLPFC in people with major depression: a UK biobank study

The anterior cingulate cortex (ACC) and right ventrolateral prefrontal cortex (VLPFC) are thought to have important roles in loneliness (feeling of social isolation/exclusion) experience or regulation and in the pathophysiology of their disturbance in major depressive disorder (MDD). However, the structural abnormalities of these regions and the correlates with loneliness in MDD across the healthy population have not fully been clarified. The study analyzed the link between loneliness and gray matter volumes (GMVs) in the ACC and right VLPFC among 1,005 patients with MDD and 7,247 healthy controls (HCs) using UK Biobank data. Significant reductions in GMV in the right VLPFC were found in MDD males compared to HCs. MDD males also showed a higher association between loneliness and reduced GMVs in the right VLPFC and bilateral ACC than HCs. No such associations were found in MDD females. The findings suggest that loneliness may influence brain structures crucial for emotion experience and regulation, particularly in middle-older aged men with MDD. This highlights the potential adverse effects of loneliness on brain structure in MDD and suggests that social engagement could have a positive impact.

The reliability and suitability of strength assessments in frail and pre-frail older adults: recommendations for strength testing in older populations

BACKGROUND

Lifelong strength is fundamental to physical function, health, and quality of life. Reliable appropriate strength assessment measures for older adults play an important role in effective evaluation of baseline ability and exercise prescription to counter disease and disuse. This study aimed to investigate the within-session reliability of maximal isometric knee extension and flexion, hip abduction and adduction, and handgrip strength measures in frail and pre-frail older adults.

METHOD

The study was conducted at a residential care home in Birmingham, UK. All care home residents aged ≥ 65 years; pre-frail or frail according to the Fried Frailty phenotype criteria; able to speak and read English; not currently involved in any other clinical trial; without severe sensory impairments; and with a predicted life expectancy greater than the trial length were eligible. Maximal isometric lower limb testing was performed using specialised resistance training equipment and a portable measurement device, and grip strength was assessed using a portable dynamometer. All eligible participants attended a single testing session and performed three trials per measure. Peak force measures were obtained for analysis. Within-session reliability for each measure was calculated from repeated-measures analysis of variance, intraclass correlation coefficients (ICC), and coefficients of variation (CV) with 95% confidence intervals.

RESULTS

Eleven frail and eleven pre-frail older adults participated in the study. Within-session absolute and relative measures were found to be reliable with the highest overall repeatability indicated between trial 2 and trial 3 for knee extension, hip abduction, and handgrip (CV ≤ 4.65%, ICC ≥ 0.96) with variation evident across all measures, except knee extension, from trial 1 to 2.

CONCLUSIONS

Overall, maximal isometric strength in frail and pre-frail older adults with no previous testing experience can be measured with good to high reliability within their first testing session. An initial two familiarisation trials followed by two measurement trials is recommended to achieve the highest level of overall repeatability.

TRIAL REGISTRATION

The trial was registered with ClinicalTrials.gov: NCT03141879 on 05/05/2017.

Cardiorespiratory Fitness and Muscular Strength Do Not Predict Social Cognitive Capacity in Older Age

OBJECTIVES

Social cognitive function often declines in older age but the mechanisms underlying these declines are not completely clear. Cardiorespiratory fitness (CRF) and muscular strength are positively associated with broader cognitive function in older adults, yet surprisingly, no study has examined whether a similar relationship exists between CRF or muscular strength and social cognition in older age.

METHODS

We assessed whether higher CRF and muscular strength were associated with enhanced social cognitive function in a sample of fifty older adults (Mage = 70.08, standard deviation = 3.93). Participants completed a gold-standard cardiopulmonary exercise test to assess CRF, an isometric handgrip strength test to index muscular strength, and validated measures of social cognition to index emotion perception and theory of mind (ToM).

RESULTS

The results showed that CRF and muscular strength did not explain any unique variance in older adults' social cognitive performance. Bayesian analyses confirmed that the evidence for the null hypothesis was moderate for all tested relationships, except for the relationship between CRF and cognitive ToM where the evidence for the null was anecdotal.

DISCUSSION

This study has provided the first evidence to suggest that CRF and muscular strength-two important modifiable lifestyle factors-are not associated with social cognition in healthy older adults. However, replication studies are now needed to cross-validate these findings and to clarify whether any moderating variables may be important for understanding the relationship between fitness and social cognition in older age.

Handgrip strength, physical activity and incident mild cognitive impairment and dementia

OBJECTIVE

We analyzed the mediating role of handgrip strength in the association between moderate to vigorous physical activity and incident mild cognitive impairment and dementia.

METHODS

We used prospective data from 14 European countries participating in the Survey of Health, Ageing, and Retirement in Europe. 19,686 participants free of dementia and mild cognitive impairment (64.9 ± 8.7 years) were followed up for a mean of 10.2 years. Moderate to vigorous physical activity was self-reported, and handgrip strength was assessed with a dynamometer. Mild cognitive impairment was defined as 1.5 standard deviations below the mean of the standardized global cognition score, while dementia was determined by physician diagnosis. Gender, age, country, education, presence of chronic diseases, depressive symptoms, limitations in activities of daily living, body mass index, and baseline cognitive levels were used as covariates. Cox proportional hazards as well as mediation models were used.

RESULTS

Moderate to vigorous physical activity for at least 1 day per week was independently associated with lower incident mild cognitive impairment (HR: 0.85; 95%CI: 0.74-0.98). A 10 % increase in handgrip strength was associated a 6 % lower hazard for incident mild cognitive impairment (0.94; 0.92-0.97) and 5 % lower hazard for incident dementia (0.95; 0.93-0.98). Handgrip strength partly mediated the association of moderate to vigorous physical activity with mild cognitive impairment (Coefficient: 0.03; 95%CI: 0.01-0.05; 17.9 %).

CONCLUSIONS

Physical activity is independently associated with a lower incidence of mild cognitive impairment.

Clinical Significance of Physical Frailty in Subjects With Subjective Cognitive Decline: A Prospective Study With Amyloid PET Data

BACKGROUND AND PURPOSE

Physical frailty is known to be closely associated with cognitive impairment and to be an early sign of Alzheimer's disease. We aimed to understand the characteristics of physical frailty and define factors associated with physical frailty in subjects with subjective cognitive decline (SCD) by analyzing amyloid data.

METHODS

We prospectively enrolled subjects with SCD from a cohort study to identify predictors for the clinical progression to mild cognitive impairment or dementia from SCD (CoSCo). All of the subjects underwent brain magnetic resonance imaging, and brain amyloid positron-emission tomography (PET) to detect amyloid beta plaques. Self-reported exhaustion, handgrip strength, and gait speed were used to measure physical frailty.

RESULTS

Of 120 subjects with SCD, 26 (21.7%) were amyloid-positive in PET. Female (odds ratio [OR]=3.79, p=0.002) and amyloid-PET-positive (OR=3.80, p=0.008) subjects with SCD were at high risks of self-reported exhaustion. Amyloid PET positivity (OR=3.22, p=0.047) and high burden from periventricular white-matter hyperintensity (OR=3.34, 95% confidence interval=1.18-9.46, p=0.023) were significantly associated with a weaker handgrip. The subjects with SCD with self-reported exhaustion and weaker handgrip presented with lower cognitive performance in neuropsychological tests, especially for information processing speed and executive function. Subjects with a slower gait performed worse in visual memory function tests.

CONCLUSIONS

Amyloid PET positivity was associated with a higher risk of self-reported exhaustion and weaker handgrip in subjects with SCD. The subjects with SCD and physical frailty also performed worse in neuropsychological tests.

Decrease in Gait Speed Over Time Is Associated With Increase in Number of Depression Symptoms in Older Adults With Type 2 Diabetes

BACKGROUND

We examined the cross-sectional and longitudinal relationships of motor functions with depression in older adults with type 2 diabetes (T2D).

METHODS

Participants (n = 984) were from the longitudinal Israel Diabetes and Cognitive Decline (IDCD) study. They were initially cognitively normal and underwent evaluations of motor functions (grip strength and gait speed) and of depression (using the 15-item version of the Geriatric Depression Scale [GDS]) approximately every 18 months. We applied Hierarchical Linear Mixed Models (HLMM) to investigate the associations between motor functions and depression adjusting for sociodemographic, cardiovascular factors, overall cognitive score, and subjective report of exhaustion.

RESULTS

Participants' baseline characteristics were 72 (±5) years of age (59.6% males), 13 (±4) years of education, Mini-Mental Status Exam (MMSE) score of 28.01 (±1.78), and a GDS score of (2 ± 2.00), consistent with normal cognitive status and lack of major affective symptomatology. Slower gait speed at baseline was associated with higher GDS scores (p = .001) and with their increase over time (p = .049). A decrease in walking speed from baseline was associated with an increase in GDS scores (p = .015). Lower grip strength at baseline was associated with higher GDS scores (p = .002), but not with trajectories in GDS scores over time. A faster decrease in grip strength from baseline was associated with a faster increase in GDS scores (p = .022).

CONCLUSIONS

Both gait speed and grip strength are cross-sectionally associated with depression. However, only gait speed and its decrease over time can potentially be used to predict incident depression symptoms, thus facilitating the introduction of depression prevention strategies.

Neighbourhood residential density, urbanicity and incident dementia and Alzheimer's disease: A 12-year prospective cohort study from the UK Biobank

INTRODUCTION

An increasing proportion of global population is exposed to urban densification in an aging society. However, little is known of the role of residential density and urbanicity on the risk of developing dementia including Alzheimer's disease. We examined long-term associations between residential density and urbanicity and risks of incident dementia and Alzheimer's disease.

METHODS

This prospective cohort study included participants from the UK Biobank who lived at the same residential address, had no self-reported neurological conditions and without dementia at baseline. Residential density was measured as the number of dwelling units within 1-km street neighbourhood of participant's home address. A composite index of urbanicity was developed from neighbourhood-level z-standardized densities of housing, retail, public transport and street centrality. Hazard ratios were derived from Cox proportional hazard models adjusted for known risk factors.

RESULTS

The analytic sample included 239,629 participants aged 38-72 years. During a median follow-up of 12.3 years (interquartile range 11.5-13.0 years), 2,176 participants developed dementia and 1,004 Alzheimer's disease. After adjustments for potential risk factors, each 1,000 units/Km2 increment in residential density was associated with higher risks of dementia (hazard ratio [HR]=1.10, 95% confidence interval [CI]: 1.06-1.15) and Alzheimer's disease (HR=1.10, 95% CI: 1.04-1.16). Consistently, categorical models showed that living in neighbourhoods of higher residential density and urbanicity were associated with higher risks of dementia (HR = 1.30, 95% CI: 1.12-1.51 for the highest density quintile compared to the lowest and HR = 1.21, 95% CI: 1.05-1.39 for the highest urbanicity quintile relative to the lowest). The associations were more pronounced in female, age >65 years, and among participants of the low income and those being frail and having shorter leucocyte telomere length (LTL).

CONCLUSIONS

Higher residential density and urbanicity was found to be positively associated with elevated risks of dementia and Alzheimer's disease. Optimizing neighbourhood residential density maybe one of the upstream considerations for mitigating against neurodegenerative diseases.

Handgrip strength is associated with learning and verbal fluency in older men without dementia: insights from the NHANES

Low handgrip strength, a hallmark measure of whole-body strength, has been linked with greater odds of cognitive decline and dementia; however, conflicting findings, which could be due to population characteristics and choice of tools, such for the assessment of handgrip strength and cognitive function domains, also exist. Therefore, we examined the relationship of handgrip strength with a comprehensive list of tests to assess domains of cognitive function using a representative sample of US older men and women without neurodegenerative disorders such as dementia. We analyzed cross-sectional data from the US National Health and Nutrition Examination Survey (NHANES) between 2011 and 2014, with a study cohort of 777 older adults (380 men and 397 women) above 60 years of age. Handgrip strength was assessed using a handgrip dynamometer, while cognitive function was assessed through the Consortium to Establish a Registry for Alzheimer's Disease (CERAD) Word List Learning Test (WLLT), Word List Recall Test (WLRT), Intrusion Word Count Test (WLLT-IC and WLRT-IC), the Animal Fluency Test (AFT), and the Digit Symbol Substitution Test (DSST). Sex-stratified multiple linear regression analyses were performed upon covariate adjustment for age, ethnicity, socio-economic status, education, medical history, body mass index, physical activity, energy, protein, and alcohol intake. Maximal handgrip strength was positively associated with cognitive function scores, including CERAD WLLT (P = 0.009, R² = 0.146) and AFT (P = 0.022, R² = 0.024) in older men, but not in women (CERAD WLLT: P = 0.253, AFT: P = 0.370). No significant associations with CERAD WLLRT (men: P = 0.057, women: P = 0.976), WLLT-IC (men: P = 0.671, women: P = 0.869), WLLRT-IC (men: P = 0.111, women: P = 0.861), and DSST (men: P = 0.108, women: P = 0.091) were observed. Dose-response curves exhibited a prominent linear relationship between all significant associations after covariate adjustment, with no indication of a plateau in these relationships. In conclusion, higher handgrip strength was independently associated with better learning ability for novel verbal information and verbal fluency in US men over the age of 60 and without dementia. Longitudinal studies are required to confirm whether muscle strength independently predicts cognitive function changes in older adults in a sex-specific manner, and whether this connection is affirmed to the possibility of reverse causation due to declines in physical activity levels in the preclinical phase of dementia.

Spatiotemporal Modeling of Grip Forces Captures Proficiency in Manual Robot Control

New technologies for monitoring grip forces during hand and finger movements in non-standard task contexts have provided unprecedented functional insights into somatosensory cognition. Somatosensory cognition is the basis of our ability to manipulate and transform objects of the physical world and to grasp them with the right amount of force. In previous work, the wireless tracking of grip-force signals recorded from biosensors in the palm of the human hand has permitted us to unravel some of the functional synergies that underlie perceptual and motor learning under conditions of non-standard and essentially unreliable sensory input. This paper builds on this previous work and discusses further, functionally motivated, analyses of individual grip-force data in manual robot control. Grip forces were recorded from various loci in the dominant and non-dominant hands of individuals with wearable wireless sensor technology. Statistical analyses bring to the fore skill-specific temporal variations in thousands of grip forces of a complete novice and a highly proficient expert in manual robot control. A brain-inspired neural network model that uses the output metric of a self-organizing pap with unsupervised winner-take-all learning was run on the sensor output from both hands of each user. The neural network metric expresses the difference between an input representation and its model representation at any given moment in time and reliably captures the differences between novice and expert performance in terms of grip-force variability.Functionally motivated spatiotemporal analysis of individual average grip forces, computed for time windows of constant size in the output of a restricted amount of task-relevant sensors in the dominant (preferred) hand, reveal finger-specific synergies reflecting robotic task skill. The analyses lead the way towards grip-force monitoring in real time. This will permit tracking task skill evolution in trainees, or identify individual proficiency levels in human robot-interaction, which represents unprecedented challenges for perceptual and motor adaptation in environmental contexts of high sensory uncertainty. Cross-disciplinary insights from systems neuroscience and cognitive behavioral science, and the predictive modeling of operator skills using parsimonious Artificial Intelligence (AI), will contribute towards improving the outcome of new types of surgery, in particular the single-port approaches such as NOTES (Natural Orifice Transluminal Endoscopic Surgery) and SILS (Single-Incision Laparoscopic Surgery).

Synergistic Effect of Increased Total Protein Intake and Strength Training on Muscle Strength: A Dose-Response Meta-analysis of Randomized Controlled Trials

Background

Protein supplementation augments muscle strength gain during resistance training. Although some studies focus on the dose-response relationship of total protein intake to muscle mass or strength, the detailed dose-response relationship between total protein intake and muscle strength increase is yet to be clarified, especially in the absence of resistance training.

Objective

We aimed to assess the detailed dose-response relationship between protein supplementation and muscle strength, with and without resistance training.

Design

Systematic review with meta-analysis.

Data Sources

PubMed and Ichushi-Web (last accessed on March 23, 2022).

Eligibility Criteria

Randomized controlled trials investigating the effects of protein intake on muscle strength.

Synthesis Methods

A random-effects model and a spline model.

Results

A total of 82 articles were obtained for meta-analyses, and data from 69 articles were used to create spline curves. Muscle strength increase was significantly augmented only with resistance training (MD 2.01%, 95% CI 1.09–2.93) and was not augmented if resistance training was absent (MD 0.13%, 95% CI − 1.53 to 1.79). In the dose-response analysis using a spline model, muscle strength increase with resistance training showed a dose-dependent positive association with total protein intake, which is 0.72% (95% CI 0.40–1.04%) increase in muscle strength per 0.1 g/kg body weight [BW]/d increase in total protein intake up to 1.5 g/kg BW/d, but no further gains were observed thereafter.

Conclusion

Concurrent use of resistance training is essential for protein supplementation to improve muscle strength. This study indicates that 1.5 g/kg BW/d may be the most appropriate amount of total protein intake for maintaining and augmenting muscle strength along with resistance training.

Supplementary Information

The online version contains supplementary material available at 10.1186/s40798-022-00508-w.

The relationship between clinical measures of cognitive function and grip strength in healthy older adults

BACKGROUND

Handgrip strength is considered a surrogate for musculoskeletal strength, however there is emerging evidence of an association with cognition. The specific neurocognitive attribute which best associates with grip strength is unknown.

METHODS

We performed a secondary analysis on baseline data in 49 healthy older adults. Grip strength was corrected for body mass index. Control independent variables included age, Montreal Cognitive Assessment, and Trails B. Experimental variables included a clinical measure of simple reaction time, and clinical and computerized go/no-go tasks. The clinical Go/No-Go measure was determined with ReacStick, a rod-shaped device which - when released by the examiner - requires the participant to decide within 390 ms whether to catch the device or let it fall to the ground.

RESULTS

Bivariate analysis demonstrated that age and all cognitive measures other than the computer go/no-go response accuracy related to grip strength. Multivariate analyses showed that following inclusion of the control variables, only ReacStick measures (reaction accuracy/simple reaction time) significantly predicted grip strength, explaining an additional 15.90% variance (p = 0.026). In contrast, computerized Go/No-Go accuracy (p = 0.391), response time variability (p = 0.463), and the control variables (p value range = 0.566-0.942) did not predict grip strength.

CONCLUSION

A short latency (< 390 ms) visuomotor Go/No-Go task independently predicted over 15% of grip strength variance, whereas a slower screen-based Go/No-Go task did not. These findings support the notion that declining grip strength likely reflects sub-clinical brain changes as well as musculoskeletal dysfunction, possibly explaining the potent relationships between grip strength, disability, chronic disease, and mortality.

Exploring the relationship between brain white matter change and higher degree of invisible hand tremor with computer technology

BACKGROUND: At present, the clinical diagnosis of white matter change (WMC) patients depends on cranial magnetic resonance imaging (MRI) technology. This diagnostic method is costly and does not allow for large-scale screening, leading to delays in the patient’s condition due to inability to receive timely diagnosis. OBJECTIVE: To evaluate whether the burden of WMC is associated with the degree of invisible hand tremor in humans. METHODS: Previous studies have shown that tremor is associated with WMC, however, tremor does not always have imaging of WMC. Therefore, to confirm that the appearance of WMC causes tremor, which are sometimes invisible to the naked eye, we achieved an optical-based computer-aided diagnostic device by detecting the invisible hand tremor, and we proposed a calculation method of WMC volume by using the characteristics of MRI images. RESULTS: Statistical analysis results further clarified the relationship between WMC and tremor, and our devices are validated for the detection of tremors with WMC. CONCLUSIONS: The burden of WMC volume is positive factor for degree of invisible hand tremor in the participants without visible hand tremor. Detection technology provides a more convenient and low-cost evaluating method before MRI for tremor diseases.

Grip force as a functional window to somatosensory cognition

Analysis of grip force signals tailored to hand and finger movement evolution and changes in grip force control during task execution provide unprecedented functional insight into somatosensory cognition. Somatosensory cognition is the basis of our ability to act upon and to transform the physical world around us, to recognize objects on the basis of touch alone, and to grasp them with the right amount of force for lifting and manipulating them. Recent technology has permitted the wireless monitoring of grip force signals recorded from biosensors in the palm of the human hand to track and trace human grip forces deployed in cognitive tasks executed under conditions of variable sensory (visual, auditory) input. Non-invasive multi-finger grip force sensor technology can be exploited to explore functional interactions between somatosensory brain mechanisms and motor control, in particular during learning a cognitive task where the planning and strategic execution of hand movements is essential. Sensorial and cognitive processes underlying manual skills and/or hand-specific (dominant versus non-dominant hand) behaviors can be studied in a variety of contexts by probing selected measurement loci in the fingers and palm of the human hand. Thousands of sensor data recorded from multiple spatial locations can be approached statistically to breathe functional sense into the forces measured under specific task constraints. Grip force patterns in individual performance profiling may reveal the evolution of grip force control as a direct result of cognitive changes during task learning. Grip forces can be functionally mapped to from-global-to-local coding principles in brain networks governing somatosensory processes for motor control in cognitive tasks leading to a specific task expertise or skill. Under the light of a comprehensive overview of recent discoveries into the functional significance of human grip force variations, perspectives for future studies in cognition, in particular the cognitive control of strategic and task relevant hand movements in complex real-world precision task, are pointed out.

Handgrip strength and the risk of major depressive disorder: a two-sample Mendelian randomisation study

Background

Major depressive disorder (MDD) is a common psychiatric disease and a leading cause of disability worldwide. Handgrip strength (HGS) as an objective physical fitness test is a practical index for identifying many diseases. Previous studies drew different conclusions about the relationship between HGS and MDD.

Aims

We aim to explore whether HGS has an effect on the risk of MDD.

Methods

HGS-related single-nucleotide polymorphisms identified by a genome-wide association study were used as instrumental variables in this Mendelian randomisation (MR) study. Summary data on MDD were obtained from the Psychiatric Genomics Consortium. Four methods were applied, including inverse variance weighted (IVW), MR Egger, weighted median and weighted mode. Additional sensitivity analyses, including leave-one-out, heterogeneity test, pleiotropy test and confounders identification, were conducted to test the robustness of our results.

Results

Each 1 kg increase in left HGS is associated with a 21.95% reduction in the risk of MDD (OR_IVW = 0.781, 95% CI: 0.650 to 0.937, p=0.009), while no significant correlation exists in the estimation of right HGS (p=0.146). Sensitivity analyses demonstrated statistical significance (β_IVW = −0.195, p=0.023) after excluding some genetic loci that cause pleiotropy.

Conclusions

Increased left HGS is associated with a reduced risk of MDD. In the future, it may be used as an index for the clinical screening, observation and treatment of MDD.

Associations between grip strength, brain structure, and mental health in > 40,000 participants from the UK Biobank

BACKGROUND

Grip strength is a widely used and well-validated measure of overall health that is increasingly understood to index risk for psychiatric illness and neurodegeneration in older adults. However, existing work has not examined how grip strength relates to a comprehensive set of mental health outcomes, which can detect early signs of cognitive decline. Furthermore, whether brain structure mediates associations between grip strength and cognition remains unknown.

METHODS

Based on cross-sectional and longitudinal data from over 40,000 participants in the UK Biobank, this study investigated the behavioral and neural correlates of handgrip strength using a linear mixed effect model and mediation analysis.

RESULTS

In cross-sectional analysis, we found that greater grip strength was associated with better cognitive functioning, higher life satisfaction, greater subjective well-being, and reduced depression and anxiety symptoms while controlling for numerous demographic, anthropometric, and socioeconomic confounders. Further, grip strength of females showed stronger associations with most behavioral outcomes than males. In longitudinal analysis, baseline grip strength was related to cognitive performance at ~9 years follow-up, while the reverse effect was much weaker. Further, baseline neuroticism, health, and financial satisfaction were longitudinally associated with subsequent grip strength. The results revealed widespread associations between stronger grip strength and increased grey matter volume, especially in subcortical regions and temporal cortices. Moreover, grey matter volume of these regions also correlated with better mental health and considerably mediated their relationship with grip strength.

CONCLUSIONS

Overall, using the largest population-scale neuroimaging dataset currently available, our findings provide the most well-powered characterization of interplay between grip strength, mental health, and brain structure, which may facilitate the discovery of possible interventions to mitigate cognitive decline during aging.

Frailty in individuals with depression, bipolar disorder and anxiety disorders: longitudinal analyses of all-cause mortality

BACKGROUND

Frailty is a medical syndrome that is strongly associated with mortality risk and an emerging global health burden. Mental disorders are associated with reduced life expectancy and elevated levels of frailty. In this study, we examined the mortality risk associated with frailty in individuals with a lifetime history of mental disorders compared to individuals without a history of mental disorders.

METHODS

The UK Biobank study recruited > 500,000 adults, aged 37-73, between 2006 and 2010. We derived the two most common albeit distinctive measures of frailty, the frailty phenotype and the frailty index. Individuals with lifetime depression, bipolar disorder or anxiety disorders were identified from multiple data sources. The primary outcome was all-cause mortality. We have also examined differences in frailty, separately by sex and age.

RESULTS

Analyses included up to 297,380 middle-aged and older adults with a median follow-up of 12.19 (interquartile range = 1.31) years, yielding 3,516,706 person-years of follow-up. We observed higher levels of frailty in individuals with mental disorders for both frailty measures. Standardised mean differences in the frailty index ranged from 0.66 (95% confidence interval [CI] 0.65-0.67) in individuals with anxiety disorders to 0.94 (95% CI 0.90-0.97) in individuals with bipolar disorder, compared to people without mental disorders. For key comparisons, individuals with a mental disorder had greater all-cause mortality hazards than the comparison group without mental disorders. The highest hazard ratio (3.65, 95% CI 2.40-5.54) was observed among individuals with bipolar disorder and frailty, relative to non-frail individuals without mental disorders.

CONCLUSIONS

Our findings highlight elevated levels of frailty across three common mental disorders. Frailty and mental disorders represent potentially modifiable targets for prevention and treatment to improve population health and life expectancy, especially where both conditions coexist.

Muscle strength and incidence of depression and anxiety: findings from the UK Biobank prospective cohort study

BACKGROUND

Depression and anxiety are the leading mental health problems worldwide; depression is ranked as the leading cause of global disability with anxiety disorders ranked sixth. Preventive strategies based on the identification of modifiable factors merit exploration. The aim of the present study was to investigate the associations of handgrip strength (HGS) with incident depression and anxiety and to explore how these associations differ by socio-demographic, lifestyle, and health-related factors.

METHODS

The analytic sample comprised 162 167 participants (55% women), aged 38-70 years, from the UK Biobank prospective cohort study. HGS was assessed at baseline using dynamometry. Depression and anxiety were extracted from primary care and hospital admission records. Cox proportional models were applied, with a 2 year landmark analysis, to investigate the associations between HGS and incident depression and anxiety.

RESULTS

Of the 162 167 participants included, 5462 (3.4%) developed depression and 6614 (4.1%) anxiety, over a median follow-up period of 10.0 years (inter-quartile range: 9.3-10.8) for depression and 9.9 (inter-quartile range: 9.0-10.8) for anxiety. In the fully adjusted model, a 5 kg lower HGS was associated with a 7% (HR: 1.07 [95% CI: 1.05, 1.10]; P < 0.001) and 8% (HR: 1.08 [95% CI: 1.06, 1.10]; P < 0.001) higher risk of depression and anxiety, respectively. Compared with participants in the sex and age-specific highest tertiles of HGS, those in the medium and lowest tertiles had an 11% (HR: 1.11 [95% CI: 1.04, 1.19]; P = 0.002) and 24% (HR: 1.24 [95% CI: 1.16, 1.33]; P < 0.001) higher risk of depression and 13% (HR: 1.13 [95% CI: 1.06, 1.20]; P < 0.001) and 27% (HR: 1.27 [95% CI: 1.19, 1.35]; P < 0.001) higher risk of anxiety, respectively. The association of HGS with depression was stronger among participants with average or brisk walking pace (vs. slow walking pace; P_interaction  < 0.001). The association with anxiety was stronger in those participants aged ≥58 years (vs. ≤58 years; P_interaction  = 0.002) and those living in more affluent areas (vs. deprived; P_interaction  = 0.001).

CONCLUSIONS

Handgrip strength was inversely associated with incident depression and anxiety. Because HGS is a simple, non-invasive, and inexpensive measure, it could be easily used in clinical practice to stratify patients and identify those at elevated risk of mental health problems. However, future research should assess if resistance training aimed at increasing HGS can prevent the occurrence of mental health conditions.

The Association Between Grip Strength and Depression Among Adults Aged 60 Years and Older: A Large-Scaled Population-Based Study From the Longitudinal Aging Study in India

Background

The association between grip strength and depression in elderly individuals in low- and middle-income countries (LMICs) has rarely been studied. This study aims to explore the relevance of grip strength and depression in the elderly population using data from a national large-scale population.

Methods

This study was conducted using data from seniors over 60 years old in wave 1 of the Longitudinal Aging Study in India (LASI). Grip strength is the maximum of three measurements by the dynamometer. Depression symptoms were assessed using 10 items on the Center for Epidemiologic Studies Depression Scale (CESD-10) with a 10-point boundary. Multivariate linear regression analysis, non-linear analysis, subgroup analysis, interaction tests and sensitivity analysis were performed.

Results

There were 27,343 participants in this study, including 19,861 participants with low grip strength and 7,482 participants with normal grip strength. The results revealed that grip strength and depression were negatively correlated in elderly individuals after adequate adjustment for confounding factors [odds ratio (OR) = 1.237, 95% confidence interval (CI) 1.172-1.305, p < 0.00001]. The results remained stable after adjusting for all confounding factors (OR = 1.090, 95% CI 1.030-1.155, p = 0.00307). Regression analysis showed that physical activity (PA), comorbidities and cognition may have an impact on the correlation between grip strength and depression symptoms. Smooth curve fit suggested that grip strength and depressive symptoms were linearly related. The interaction test results of gender in the relationship between grip strength and depression were significant (p for interaction < 0.05).

Conclusion

Grip strength and depression were negatively correlated in older Indians, and larger prospective studies are needed in the future to determine this association.

Handgrip strength and all-cause dementia incidence and mortality: findings from the UK Biobank prospective cohort study

BACKGROUND

This study aimed to investigate the associations of grip strength with incidence and mortality from dementia and whether these associations differ by sociodemographic and lifestyle factors.

METHODS

A total of 466 788 participants of the UK Biobank (median age 56.5 years, 54.5% women). The outcome was all-cause dementia incidence and mortality and the exposure was grip strength. Grip strength was assessed using a Jamar J00105 hydraulic hand dynamometer.

RESULTS

Excluding the first 2 years of follow-up (landmark analysis), mean follow-up was 9.1 years (inter-quartile range: 8.3; 9.7) for incidence and 9.3 (inter-quartile range: 8.7; 10.0) for mortality. During this time, 4087 participants developed dementia, and 1309 died from it. Lower grip strength was associated with a higher risk of dementia incidence and mortality independent of major confounding factors (P < 0.001). Individuals in the lowest quintile of grip strength had 72% [95% confidence interval (CI): 1.55; 1.92] higher incident dementia risk and 87% [95% CI: 1.55; 2.26] higher risk of dementia mortality compared with those in the highest quintile. Our PAF analyses indicate that 30.1% of dementia cases and 32.3% of dementia deaths are attributable to having low grip strength. The association between grip strength and dementia outcomes did not differ by lifestyle or sociodemographic factors.

CONCLUSIONS

Lower grip strength was associated with a higher risk of all-cause dementia incidence and mortality, independently of important confounding factors.

Associations Between Handgrip Strength and Dementia Risk, Cognition, and Neuroimaging Outcomes in the UK Biobank Cohort Study

IMPORTANCE

The associations between muscle strength and cognitive outcomes have sparked interest in interventions that increase muscle strength for prevention of dementia, but the associations between muscle strength and cognitive aging are unclear, particularly among middle-aged adults.

OBJECTIVE

To evaluate the association between handgrip strength (HGS) and dementia, reduced cognition, and poorer neuroimaging outcomes in a UK population of middle-aged adults.

DESIGN, SETTING, AND PARTICIPANTS

This cohort study evaluated UK Biobank participants aged 39 to 73 years enrolled from 2006 to 2010 with measured HGS and prospectively followed up for dementia diagnosis. Data were analyzed from October 2021 to April 2022.

EXPOSURES

HGS assessed in both hands via dynamometer.

MAIN OUTCOMES AND MEASURES

Outcomes included cognitive test scores (fluid intelligence and prospective memory), brain magnetic resonance imaging measures (total brain volume, white matter hyperintensity, and hippocampal volume), and incident dementia (all-cause, vascular, and Alzheimer disease [AD] from primary care, hospital, or death records) over a median (IQR) of 11.7 (11.0-12.4) years of follow-up. Mixed-effects linear and logistic regressions and Cox proportional-hazard models were used to estimate associations, stratified by gender and adjusted for covariates. Estimates are presented per 5-kg decrement in HGS. To evaluate reverse causation, we assessed whether a polygenic risk score for AD is associated with HGS.

RESULTS

A subsample of 190 406 adult participants in the UK Biobank (mean [SD] age, 56.5 [8.1] years; 102 735 women [54%]) were evaluated. A 5-kg decrement in HGS was associated with lower fluid intelligence scores in men (β, -0.007; 95% CI, -0.010 to -0.003) and women (β, -0.04; 95% CI, -0.05 to -0.04. A 5-kg decrement in HGS was associated with worse odds of correctly responding to a prospective memory task for men (odds ratio, 0.91; 95% CI, 0.90 to 0.92) and women (odds ratio, 0.88; 95% CI, 0.87 to 0.90). A 5-kg decrement in HGS was associated with greater white matter hyperintensity volume in men (β, 92.22; 95% CI, 31.09 to 153.35) and women (β, 83.56; 95% CI, 13.54 to 153.58). A 5-kg decrement in HGS was associated with incident dementia for men (hazard ratio, 1.20; 95% CI, 1.12 to 1.28) and women (hazard ratio, 1.12; 95% CI, 1.00 to 1.26). The AD genetic risk score was not significantly associated with HGS.

CONCLUSIONS AND RELEVANCE

These findings suggest that HGS is associated with measures of neurocognitive brain health among men and women and they add to a growing body of research indicating that interventions designed to increase muscle strength, particularly among middle-aged adults, may hold promise for the maintenance of neurocognitive brain health.

Deficits in rate of force production during multifinger tasks are associated with cognitive status

OBJECTIVES

The multifinger force deficit (MFFD) is the decline in force generated by an individual finger as the number of fingers contributing to the action is increased. It has been proposed that as a measure of neural sufficiency rather than muscle status, it provides a means of detecting individuals at risk of cognitive decline. Age-related deficits in central neural drive exert a disproportionate impact on the rate at which force can be generated. We examined whether a MFFD derived from the maximum rate at which force is generated, is more sensitive to individual differences in cognitive status, than one calculated using the maximum level of force.

METHODS

Monotonic associations between each of two variants of the MFFD, and cognition (measured with the Montreal Cognitive Assessment), were estimated cross sectionally using generalized partial rank correlations, in which age, level of education and degree of handedness were included as covariates. The participants (n=26) were community dwelling adults aged 66-87.

RESULTS

The MFFD derived using the maximum rate of force development was negatively associated with cognitive status. The association for the MFFD based on the maximum level of force, was not statistically reliable. The associations with cognitive status obtained for both variants of the MFFD were of greater magnitude than those reported previously for standard grip strength dynamometry.

CONCLUSION

The sensitivity with which the MFFD detects risk of cognitive decline may be enhanced by using the maximum rate of force developed by each finger, rather than the maximum force generated by each finger.

Weak Hand Grip Strength Is Associated with Alexithymia in Outpatients in a Mexican Population

Hand grip strength has been considered as a possible marker for metabolic and psychiatric disease. To date, however, no research has focused on the association between alexithymia and hand grip strength. The objective of the present study was to investigate the correct association between hand grip strength and alexithymia. A cross-sectional study was carried out in Comalcalco, Tabasco, México. A total of 246 individuals were included. Hand grip strength was evaluated in the dominant hand using a Takei^® portable digital dynamometer. Alexithymia was measured using the Toronto Alexithymia Scale (TAS-20). Two linear regression models adjusted by confounders were used to determine the association between alexithymia and hand grip strength. The rate for positive alexithymia was 39.0% (n = 94). Individuals with alexithymia showed a weaker hand grip strength than the comparison group (t = 2.4, 244 df, p = 0.01). Individuals with alexithymia had significantly reduced levels of hand grip strength (β = −0.39 ± 0.14; p = 0.006); after additional adjustment for clinical variables, decreased hand grip strength remained (β = 8.00 ± 1.86; p ≤ 0.001). Our results suggest that a decrease in hand grip strength could be associated with alexithymia. This measurement could be useful as a predictive marker for the identification of alexithymia in Mexican individuals who attend outpatient clinics.

Preventive Effect of Hippocampal Sparing on Cognitive Dysfunction of Patients Undergoing Whole-Brain Radiotherapy and Imaging Assessment of Hippocampal Volume Changes

Objective

Preventive effect of hippocampal sparing on cognitive dysfunction of patients undergoing whole-brain radiotherapy and imaging assessment of hippocampal volume changes.

Methods

Forty patients with brain metastases who attended Liaoning Cancer Hospital from January 2018 to December 2019 were identified as research subjects and were randomly divided into a control group and an experimental group, with 20 cases in each group. The control group was treated with whole-brain radiotherapy (WBRT), and the experimental group was treated with hippocampal sparing-WBRT (HS-WBRT). The Montreal Cognitive Assessment (MoCA) score, Eastern Cooperative Oncology Group (ECOG) score, cancer quality-of-life questionnaire (QLQ-C3O) score, hippocampal volume changes, and prognosis of the two groups were compared.

Results

The MoCA scores decreased in both groups at 3, 6, and 12 months after radiotherapy, with significantly higher scores in the experimental group than in the control group (P < 0.05). After radiotherapy, both groups had lower ECOG scores, with those in the experimental group being significantly lower than those in the control group (P < 0.05). After radiotherapy, the QLQ-C30 score was elevated in both groups, and that of the experimental group was significantly higher than that of the control group (P < 0.05). The experimental group outperformed the control group in terms of the prognosis (P < 0.05). The hippocampal volume of the control group was significantly smaller than that of the experimental group (P < 0.05).

Conclusion

The application of hippocampal sparing in patients receiving whole-brain radiotherapy is effective in preventing cognitive dysfunction, improving the quality of life and prognosis of patients, and avoiding shrinkage of hippocampal volume.

A Link between Handgrip Strength and Executive Functioning: A Cross-Sectional Study in Older Adults with Mild Cognitive Impairment and Healthy Controls

Older adults with amnestic mild cognitive impairment (aMCI) who in addition to their memory deficits also suffer from frontal-executive dysfunctions have a higher risk of developing dementia later in their lives than older adults with aMCI without executive deficits and older adults with non-amnestic MCI (naMCI). Handgrip strength (HGS) is also correlated with the risk of cognitive decline in the elderly. Hence, the current study aimed to investigate the associations between HGS and executive functioning in individuals with aMCI, naMCI and healthy controls. Older, right-handed adults with amnestic MCI (aMCI), non-amnestic MCI (naMCI), and healthy controls (HC) conducted a handgrip strength measurement via a handheld dynamometer. Executive functions were assessed with the Trail Making Test (TMT A&B). Normalized handgrip strength (nHGS, normalized to Body Mass Index (BMI)) was calculated and its associations with executive functions (operationalized through z-scores of TMT B/A ratio) were investigated through partial correlation analyses (i.e., accounting for age, sex, and severity of depressive symptoms). A positive and low-to-moderate correlation between right nHGS (rp (22) = 0.364; p = 0.063) and left nHGS (rp (22) = 0.420; p = 0.037) and executive functioning in older adults with aMCI but not in naMCI or HC was observed. Our results suggest that higher levels of nHGS are linked to better executive functioning in aMCI but not naMCI and HC. This relationship is perhaps driven by alterations in the integrity of the hippocampal-prefrontal network occurring in older adults with aMCI. Further research is needed to provide empirical evidence for this assumption.

Prospective Associations of Leisure-Time Physical Activity With Psychological Distress and Well-Being: A 12-Year Cohort Study

OBJECTIVE

This study aimed to investigate the associations of leisure-time physical activity with psychological distress and well-being, and potential mediators.

METHODS

We used data from the 1970 British Cohort Study (n = 5197; 2688 men), including waves 34y (2004), 42y (2012), and 46y (2016). Participants reported leisure-time physical activity frequency and intensity (exposure) at age 34 years (baseline); cognition (vocabulary test), body mass index, disability, mobility and pain perception (potential mediators) at age 42 years; and psychological distress (Malaise Inventory) and well-being (Warwick-Edinburgh scale) at age 46 years. Baseline confounders included sex, country, education, employment status, alcohol use, tobacco smoking, and psychological distress. Main analyses included logistic regression and mediation models.

RESULTS

Higher leisure-time physical activity intensity at baseline was associated with lower psychological distress at 46y (β = -0.038 [95% confidence interval {CI} =-0.069 to -0.007]), but not leisure-time physical activity frequency. Baseline leisure-time physical activity frequency and intensity were associated with higher psychological well-being at 46y (frequency: β = 0.089 [95% CI = 0.002 to 0.176]; intensity: β = 0.262 [95% CI = 0.123 to 0.401]); and total: β = 0.041 [95% CI = 0.013 to 0.069]). Only body mass index at 42y partially mediated the association between leisure-time physical activity frequency (15.7%) and total leisure-time physical activity (6.2%) at 34y, with psychological well-being at 46y.

CONCLUSIONS

Our findings highlight the role of leisure-time physical activity in psychological distress and well-being, with greater effect sizes associated with higher frequency and intensity of leisure-time physical activity. Future interventions should consider examining potential mediators of the association of leisure-time physical activity with psychological well-being, such as body mass index.

The short and long-term effects of aerobic, strength, or mixed exercise programs on schizophrenia symptomatology

The purpose of this study was to compare the effects of three different physical exercise programs on the symptomatology, body composition, physical activity, physical fitness, and quality of life of individuals with schizophrenia. A total of 432 patients were assessed for eligibility and 86 were randomized into the aerobic (n = 28), strength (n = 29) or mixed (n = 29) groups. Positive, negative, and general symptoms of psychosis, body mass index (BMI), physical activity (IPAQ-SF), physical fitness (6-min walk test [6MWT] and hand-grip strength [HGS]), and quality of life (WHOQUOL-BREF) were assessed at baseline, post-intervention (16 weeks), and at 10-months. Our results at 16 weeks showed significant improvements in all three groups in the negative, general, and total symptoms with moderate to large effect sizes (P < 0.01, η_p² > 0.11), no change in the BMI, 6MWT or IPAQ-SF, and a significant improvement in the HGS test in the strength and mixed groups (P ≤ 0.05, η_p² > 0.08). Nonetheless, all the improvements had disappeared at 10 months. We concluded that 3 weekly sessions of a moderate to vigorous progressive exercise program for 16 weeks improved the symptomatology of individuals with schizophrenia in all three groups, with no differences between them. However, the effects had declined to baseline levels by the 10-month follow-up, suggesting that exercise interventions should be maintained over time.

Comparison of three different exercise training modalities (aerobic, strength and mixed) in patients with schizophrenia: study protocol for a multicentre randomised wait-list controlled trial

INTRODUCTION

Numerous studies support the practice of different physical exercise modalities as an effective treatment to address the problems associated with schizophrenia, reporting that they result in improvements in patient symptoms and quality of life. Given the lack of studies comparing different types of training in controlled environments, the aim of this proposed study will be to compare the effects of three physical exercise programmes (strength, aerobic and mixed) on the symptoms, body composition, level of physical activity and health-related quality of life of patients with schizophrenia.

METHODS AND ANALYSIS

A multicentre, single-blinded (evaluator), randomised, wait-list controlled (ratio 2:2:2:1) trial will be conducted with 105 patients recruited from different psychosocial care centres. The participants will be randomised into three 16-week training groups comprising 48 sessions lasting 1 hour each, or to the wait-list control group. The training groups will complete aerobic, strength or mixed (aerobic+strength) training. The participants will be assessed before, immediately after and 6 months after the end of the intervention. The patients in the wait-list control group (n=15) will receive one of the three trainings immediately after the intervention. The study variables will include positive, negative and general symptomology (Positive and Negative Syndrome Scale) as the primary outcome; as secondary outcome: body composition (by assessing body mass index, body fat mass and waist circumference), physical activity levels (International Physical Activity Questionnaire-Short Form) and quality of life (abbreviated WHO Quality of Life questionnaire).

ETHICS AND DISSEMINATION

This study was approved by the ethics committees for Biomedical Research at the CEU Cardenal Herrera University of Valencia, Spain (CEI18/215). Participants will be fully informed of the purpose and procedures of the study, and written informed consent will be obtained. The results from this study will be published in peer-reviewed journals and presented in scientific conferences.

TRIAL REGISTRATION NUMBER

NCT04987151.

Grip strength from midlife as an indicator of later-life brain health and cognition: evidence from a British birth cohort

BACKGROUND

Grip strength is an indicator of physical function with potential predictive value for health in ageing populations. We assessed whether trends in grip strength from midlife predicted later-life brain health and cognition.

METHODS

446 participants in an ongoing British birth cohort study, the National Survey of Health and Development (NSHD), had their maximum grip strength measured at ages 53, 60-64, and 69, and subsequently underwent neuroimaging as part of a neuroscience sub-study, referred to as "Insight 46", at age 69-71. A group-based trajectory model identified latent groups of individuals in the whole NSHD cohort with below- or above-average grip strength over time, plus a reference group. Group assignment, plus standardised grip strength levels and change from midlife were each related to measures of whole-brain volume (WBV) and white matter hyperintensity volume (WMHV), plus several cognitive tests. Models were adjusted for sex, body size, head size (where appropriate), sociodemographics, and behavioural and vascular risk factors.

RESULTS

Lower grip strength from midlife was associated with smaller WBV and lower matrix reasoning scores at age 69-71, with findings consistent between analysis of individual time points and analysis of trajectory groups. There was little evidence of an association between grip strength and other cognitive test scores. Although greater declines in grip strength showed a weak association with higher WMHV at age 69-71, trends in the opposite direction were seen at individual time points with higher grip strength at ages 60-64, and 69 associated with higher WMHV.

CONCLUSIONS

This study provides preliminary evidence that maximum grip strength may have value in predicting brain health. Future work should assess to what extent age-related declines in grip strength from midlife reflect concurrent changes in brain structure.

Cross-Sectional Examination of Homocysteine Levels with Sarcopenia and Its Components in Memory Clinic Outpatients

BACKGROUND

Homocysteine is a common risk factor for cognitive impairment and sarcopenia. However, very few studies have shown an association between sarcopenia and serum homocysteine levels after adjustment for cognitive function.

OBJECTIVE

The purpose of this study was to investigate the relationship between homocysteine and sarcopenia in memory clinic patients.

METHODS

This cross-sectional study investigated outpatients in a memory clinic. We enrolled 1,774 participants (≥65 years old) with measured skeletal muscle mass index (SMI), hand grip strength (HGS), and homocysteine. All participants had undergone cognitive assessments and were diagnosed with dementia, mild cognitive impairment, or normal cognition. Patient characteristics were compared according to sarcopenia presence, SMI level, or HGS. Multivariate logistic regression analysis was performed to determine the association of homocysteine with sarcopenia, low SMI, or low HGS. Next, linear regression analysis was performed using HGS as a continuous variable.

RESULTS

Logistic regression analysis showed that low HGS was significantly associated with homocysteine levels (p = 0.002), but sarcopenia and low SMI were not. In linear regression analysis, HGS was negatively associated with homocysteine levels after adjustment for Mini-Mental State Examination score (β= -2.790, p < 0.001) or clinical diagnosis of dementia (β= -3.145, p < 0.001). These results were similar for men and women.

CONCLUSION

Our results showed a negative association between homocysteine and HGS after adjustment for cognitive function. Our findings strengthen the assumed association between homocysteine and HGS. Further research is needed to determine whether lower homocysteine levels lead to prevent muscle weakness.

Higher Handgrip Strength Is Linked to Better Cognitive Performance in Chinese Adults with Hypertension

OBJECTIVE

There is growing evidence that in adults, higher levels of handgrip strength (HGS) are linked to better cognitive performance. However, the relationship between HGS and cognitive performance has not been sufficiently investigated in special cohorts, such as individuals with hypertension who have an intrinsically higher risk of cognitive decline. Thus, the purpose of this study was to examine the relationship between HGS and cognitive performance in adults with hypertension using data from the Global Ageing and Adult Health Survey (SAGE).

METHODS

A total of 4486 Chinese adults with hypertension from the SAGE were included in this study. Absolute handgrip strength (aHGS in kilograms) was measured using a handheld electronic dynamometer, and cognitive performance was assessed in the domains of short-term memory, delayed memory, and language ability. Multiple linear regression models were fitted to examine the association between relative handgrip strength (rHGS; aHGS divided by body mass index) and measures of cognitive performance.

RESULTS

Overall, higher levels of rHGS were associated with higher scores in short-term memory (β = 0.20) and language (β = 0.63) compared with the lowest tertiles of rHGS. In male participants, higher HGS was associated with higher scores in short-term memory (β = 0.31), language (β = 0.64), and delayed memory (β = 0.22). There were no associations between rHGS and cognitive performance measures in females.

CONCLUSION

We observed that a higher level of rHGS was associated with better cognitive performance among hypertensive male individuals. Further studies are needed to investigate the neurobiological mechanisms, including sex-specific differences driving the relationship between measures of HGS and cognitive performance in individuals with hypertension.

Lifetime depression and age-related changes in body composition, cardiovascular function, grip strength and lung function: sex-specific analyses in the UK Biobank

Individuals with depression, on average, die prematurely, have high levels of physical comorbidities and may experience accelerated biological ageing. A greater understanding of age-related changes in physiology could provide novel biological insights that may help inform strategies to mitigate excess mortality in depression. We used generalised additive models to examine age-related changes in 15 cardiovascular, body composition, grip strength and lung function measures, comparing males and females with a lifetime history of depression to healthy controls. The main dataset included 342,393 adults (mean age = 55.87 years, SD = 8.09; 52.61% females). We found statistically significant case-control differences for most physiological measures. There was some evidence that age-related changes in body composition, cardiovascular function, lung function and heel bone mineral density followed different trajectories in depression. These differences did not uniformly narrow or widen with age and differed by sex. For example, BMI in female cases was 1.1 kg/m2 higher at age 40 and this difference narrowed to 0.4 kg/m2 at age 70. In males, systolic blood pressure was 1 mmHg lower in depression cases at age 45 and this difference widened to 2.5 mmHg at age 65. These findings suggest that targeted screening for physiological function in middle-aged and older adults with depression is warranted to potentially mitigate excess mortality.

Identification of novel and rare variants associated with handgrip strength using whole genome sequence data from the NHLBI Trans-Omics in Precision Medicine (TOPMed) Program

Handgrip strength is a widely used measure of muscle strength and a predictor of a range of morbidities including cardiovascular diseases and all-cause mortality. Previous genome-wide association studies of handgrip strength have focused on common variants primarily in persons of European descent. We aimed to identify rare and ancestry-specific genetic variants associated with handgrip strength by conducting whole-genome sequence association analyses using 13,552 participants from six studies representing diverse population groups from the Trans-Omics in Precision Medicine (TOPMed) Program. By leveraging multiple handgrip strength measures performed in study participants over time, we increased our effective sample size by 7-12%. Single-variant analyses identified ten handgrip strength loci among African-Americans: four rare variants, five low-frequency variants, and one common variant. One significant and four suggestive genes were identified associated with handgrip strength when aggregating rare and functional variants; all associations were ancestry-specific. We additionally leveraged the different ancestries available in the UK Biobank to further explore the ancestry-specific association signals from the single-variant association analyses. In conclusion, our study identified 11 new loci associated with handgrip strength with rare and/or ancestry-specific genetic variations, highlighting the added value of whole-genome sequencing in diverse samples. Several of the associations identified using single-variant or aggregate analyses lie in genes with a function relevant to the brain or muscle or were reported to be associated with muscle or age-related traits. Further studies in samples with sequence data and diverse ancestries are needed to confirm these findings.

Eight-week high-intensity interval training is associated with improved sleep quality and cardiorespiratory fitness in patients with depressive disorders

PURPOSE

This study aimed to examine the effect of high-intensity interval training (HIIT) on both sleep and cardiorespiratory fitness in patients with depression.

METHODS

Using a single pre- and post-test study design with no control group, 82 patients diagnosed with depressive disorders underwent HIIT comprising a total of 24 15-min sessions, three times per week for 8 weeks. Depressive symptoms, sleep quality, and cardiorespiratory fitness were evaluated using the Beck depression inventory-II, the Pittsburgh sleep quality index (PSQI), and cardiopulmonary exercise testing (CPET) in the form of maximum oxygen uptake (VO₂ max), respectively.

RESULTS

All 82 patients completed the intervention. HIIT training was associated with significant improvements in BDI-II score (diff =  - 1.57 [95% CI - 2.40 to - 0.73], P = 0.001), PSQI score (diff =  - 1.20 [95% CI - 2.10 to - 0.32], P = 0.008), and CPET VO₂ max (diff = 0.95 [95% CI 0.62-1.28], P = 0.001). Effect size calculations revealed that the greatest improvement occurred in CPET VO₂ max (Cohen's d = 0.64) and that improvements in the BDI-II and PSQI scores were somewhat smaller in magnitude (Cohen's d =  - 0.41 and - 0.30, respectively). Sleep quality improvements were observed in sleep latency, habitual sleep efficiency, and the use of sleep-promoting medications (Cohen's d = 0.18, 0.19, and 0.25, respectively). Change in cardiorespiratory fitness successfully predicted change in sleep quality but not in depressive symptoms. Adverse effects were limited to minor injuries which did not interfere with completion of training.

CONCLUSIONS

HIIT training delivered over 8 weeks was associated with improvements in depression symptoms, sleep quality, and cardiorespiratory fitness in patients with depressive disorders.

Exercise Reduces Pain and Deleterious Histological Effects in Fibromyalgia-like Model

Fibromyalgia (FM) is characterized by chronic pain and associated comorbidities such as fatigue, anxiety, depression, and sleep disorders. There is a large amount of evidence regarding the benefits of physical exercise in controlling chronic pain. However, there is no consensus on which exercise modality is most suitable and the real benefits of this intervention to treat FM symptoms. The present study investigated the analgesic and antidepressant effects and morphophysiological responses induced by different physical exercise (aerobic and strength protocols) during the experimental model of FM. Spontaneous pain, mechanical hyperalgesia, thermal allodynia, depression-related behavior, and locomotor activity were evaluated weekly, as well as the morphological evaluation of the spinal cord and dorsal root ganglion. Aerobic and strength training protocols consistently abolished nociceptive behaviors, reducing spontaneous pain scores, cold allodynia, and frequency of response to mechanical hyperalgesia. The strength exercise modulated the depressive-like behavior. Finally, our data demonstrated that physical exercise performed for two weeks increased the number of glial cells in the dorsal root horn. However, it was not sufficient to control the other deleterious effects of the reserpine model on the spinal cord and the dorsal root. Together, these results demonstrated that different physical exercise modalities, when performed regularly in mice, proved to be effective and safe non-pharmacological alternatives for the treatment of FM. However, some gaps have yet to be studied regarding the neuroadaptive effects of physical exercise.

Leisure-time exercise is associated with lower depressive symptoms in community dwelling adults

Physical activity has been associated with enhanced mental health among adults. However, it is not clear in the literature which domains (occupational, transport and leisure-time exercise) and intensities (moderate, vigorous and moderate-to-vigorous) of activity provide the greatest benefits. The aim of the present study was to describe the association of different domains and intensities of physical activity with depressive symptoms in adults. This was a cross-sectional observational study conducted among 209 adults (≥18 years) in Brazil. Depressive symptoms were assessed using the HADS questionnaire (Hospital Anxiety and Depression Scale). Physical activity intensities (moderate, vigorous and moderate-to-vigorous) were device-measured by accelerometry. Physical activity in different domains (occupational, transport, and leisure-time exercise) was self-reported using a questionnaire. Chronological age, ethnicity, body mass index, highest academic achievement, employment status, alcohol consumption, tobacco smoking, chronic morbidity and soft-drink ingestion were adopted as adjustment confounding factors. Linear regression analysis revealed that total self-reported physical activity [β = -0.100 (95%CI: -0.180 to -0.019)] and leisure-time exercise [β = -0.311 (95%CI: -0.468 to -0.155)] were negatively associated with depressive symptoms, but only leisure-time exercise remained significant after adjustment for confounding factors [β = -0.243 (95%CI: -0.409 to -0.076)]. Thus, leisure-time exercise was cross-sectionally associated with lower depressive symptoms in community-dwelling adults.Highlights Leisure-time physical activity was the only physical activity domain associated with lower depressive symptoms.This association appears to be independent of potential confounders.Potential interventions should focus on leisure-time domain.