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 (Aß) retention had distinctive relationships with each measure. In the path model, brain atrophy resulting in cognitive impairment was mediated by Aß 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 Aß. Muscle mass is mainly associated with Aß 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.

Direct and indirect monitoring methods for nitrous oxide emissions in full-scale wastewater treatment plants: A critical review.

Mitigation of nitrous oxide (N2O) emissions in full-scale wastewater treatment plant (WWTP) has become an irreversible trend to adapt the climate change. Monitoring of N2O emissions plays a fundamental role in understanding and mitigating N2O emissions. This paper provides a comprehensive review of direct and indirect N2O monitoring methods. The techniques, strengths, limitations, and applicable scenarios of various methods are discussed. We conclude that the floating chamber technique is suitable for capturing and interpreting the spatiotemporal variability of real-time N2O emissions, due to its long-term in-situ monitoring capability and high data acquisition frequency. The monitoring duration, location, and frequency should be emphasized to guarantee the accuracy and comparability of acquired data. Calculation by default emission factors (EFs) is efficient when there is a need for ambiguous historical N2O emission accounts of national-scale or regional-scale WWTPs. Using process-specific EFs is beneficial in promoting mitigation pathways that are primarily focused on low-emission process upgrades. Machine learning models exhibit exemplary performance in the prediction of N2O emissions. Integrating mechanistic models with machine learning models can improve their explanatory power and sharpen their predictive precision. The implementation of the synergy of nutrient removal and N2O mitigation strategies necessitates the calibration and validation of multi-path mechanistic models, supported by long-term continuous direct monitoring campaigns.

Physical Activity, Sedentary Behavior, and Their Predictors Among Nursing Home Residents-Cross-Sectional Results of the BaSAlt Study.

Little is known about physical activity (PA) and sedentary behavior (SB) among nursing home residents although PA is known as a health promoter. This study examined PA, SB, and their predictors among nursing home residents (n = 63). Dependent variables were accelerometry-based PA and SB. Predictor variables included in a path analysis were age, sex, body mass index, Barthel Index, cognitive status (Mini-Mental State Examination), physical performance (hand grip strength and habitual walking speed), and well-being (World Health Organization-5 well-being index). PA was very low (M steps per day = 2,433) and SB was high (M percentage of sedentary time = 89.4%). PA was significantly predicted by age (ß = -0.27, p = .008), body mass index (ß = -0.29, p = .002), Barthel Index (ß = 0.24, p = .040), and hand grip strength (ß = 0.30, p = .048). SB was significantly predicted by body mass index (ß = 0.27, p = .008) and Barthel Index (ß = -0.30, p = .012). Results might be helpful for everyday practice to identify individuals at high risk for low PA and high SB.

Online Self-Disclosure and Self-Concept Clarity Among Chinese Middle School Students: A Longitudinal Study.

The relationship between online self-disclosure and self-concept clarity has been previously examined through cross-sectional studies. This study examined causal connections between online self-disclosure and self-concept clarity among Chinese middle school students using longitudinal data collected over 18 months. Participants were 535 seventh-grade students aged 12-14 years (Mage = 12.93, SD = 0.54, 43.18% girls), assessed four times, six months apart. In a random intercept cross-lagged panel model, self-concept clarity significantly predicted online self-disclosure. Latent growth mixture modeling identified two distinct growth trajectories for both online self-disclosure (Rapid change, 7%; Slow change, 93%) and self-concept clarity (Rapid change, 8%; No change, 92%). Multiple logistic regression analysis suggested that changes in self-concept clarity influenced the developmental trajectory profile of online self-disclosure. Although male and female students differed in online self-disclosure and self-concept clarity, gender differences in the developmental trajectory profiles of online self-disclosure and self-concept clarity were not significant. Supporting adolescents in developing a clear self-concept to mitigate risks associated with excessive online self-disclosure is important.

The bidirectional relationship between head injuries and conduct problems: longitudinal modelling of a population-based birth cohort study.

Childhood head injuries and conduct problems increase the risk of aggression and criminality and are well-known correlates. However, the direction and timing of their association and the role of their demographic risk factors remain unclear. This study investigates the bidirectional links between both from 3 to 17 years while revealing common and unique demographic risks. A total of 8,603 participants (50.2% female; 83% White ethnicity) from the Millennium Cohort Study were analysed at 6 timepoints from age 3 to 17. Conduct problems were parent-reported for ages 3 to 17 using the Strengths and Difficulties Questionnaire (SDQ) and head injuries at ages 3 to 14. A cross-lagged path model estimated the longitudinal bidirectional effects between the two whilst salient demographic risks were modelled cumulatively at three ecological levels (child, mother, and household). Conduct problems at age 5 promoted head injuries between 5 and 7 (Z = 0.07; SE = 0.03; 95% CI, 0.02-0.13), and head injuries at ages 7 to 11 promoted conduct problems at age 14 (ß = .0.06; SE = .0.03; 95% CI, 0.01-0.12). Head injuries were associated with direct child-level risk at age 3, whereas conduct problems were associated with direct risks from all ecological levels until 17 years. The findings suggest a sensitive period at 5-11 years for the bidirectional relationship shared between head injuries and conduct problems. They suggest that demographic risks for increased head injuries play an earlier role than they do for conduct problems. Both findings have implications for intervention timing.

Improved efficiency of Sedum lineare (Crassulaceae) in remediation of arsenic-contaminated soil by phosphate-dissolving strain P-1 in association with phosphate rock.

The selection of appropriate plants and growth strategies is a key factor in improving the efficiency and universal applicability of phytoremediation. Sedum lineare grows rapidly and tolerates multiple adversities. The effects of inoculation of Acinetobacter sp. phosphate solubilizing bacteria P-1 and application of phosphate rock (PR) as additives on the remediation efficiency of As-contaminated soil by S. lineare were investigated. Compared with the control, both the single treatment and the combination of inoculation with strain P-1 and application of PR improved the biomass by 30.7-395.5%, chlorophyll content by 48.1-134.8%, total protein content by 12.5-92.4% and total As accumulation by 45.1-177.5%, and reduced the As-induced oxidative damage. Inoculation with strain P-1 increased the activities of superoxide dismutases and catalases of S. lineare under As stress, decreased the accumulation of reactive oxygen species in plant tissues and promoted the accumulation of As in roots. In contrast, simultaneous application of PR decreased As concentration in S. lineare tissues, attenuated As-induced lipid peroxidation and improved As transport to shoots. In addition, the combined application showed the best performance in improving resistance and biomass, which significantly increased root length by 149.1%, shoot length by 33%, fresh weight by 395.5% and total arsenic accumulation by 159.2%, but decreased the malondialdehyde content by 89.1%. Our results indicate that the combined application of strain P-1 and PR with S. lineare is a promising bioremediation strategy to accelerate phytoremediation of As-contaminated soils.

Emotional non-acceptance mediates the relationship between insecure attachment and specific psychopathology in women with eating disorders.

OBJECTIVE: Insecure attachment is considered a general risk factor for eating disorders (ED). Emotion dysregulation has been proposed as one of the possible mechanisms by which attachment insecurity may affect ED psychopathology. Aim of the present study was to investigate whether difficulties in acceptance of emotions or emotional clarity may mediate the connection between insecure attachment and ED psychopathology. METHOD: One hundred and twenty patients participated and completed the Italian version of Eating Disorder Inventory-2, Experience in Close Relationship questionnaire and Difficulties in Emotion Regulation Scale. A mediator path model was performed, in which insecure attachment dimensions were set as independent variables, ED specific psychopathology measures as dependent variables, and non-acceptance of emotion and lack of emotional clarity as mediators. RESULTS: The association between both attachment avoidance and anxiety and ED specific symptoms was mediated by emotional non-acceptance, but not by emotional clarity. CONCLUSIONS: This study showed the importance to address emotion regulation in individuals with ED, focussing on improving emotional acceptance. Exploring early developmental processes which lead to non-acceptance of emotions could improve this psychological trait in people with ED.

Detoxification mechanisms of biochar on plants in chromium contaminated soil: Chromium chemical forms and subcellular distribution.

The complete pathway of chromium (Cr) transfer from soil to plant tissues and subcellular components under biochar amendment remains to be quantified, as well as the involved diverse detoxification processes in roots and stems respectively. Pot experiments and quantitative analysis were conducted to investigate Cr fixation in soil amended with Enteromorpha prolifera-derived biochar and subsequent phytoprocesses (Cr uptake, transfer, and phytotoxicity) in cultivated Secale cereale L. (rye). The results indicated that adding 5-30 g kg-1 of biochar increased the residual form of Cr (B4) in soil by 8-21% and decreased the bioavailable form of Cr (B1) by 9-29%. For Cr transferred to rye, Cr in the rye was mainly present in the low-toxicity bound state, with the acetic acid-extracted Cr (F4) (45-54%) in roots and the NaCl-extracted Cr (F3) (37-47%) in stems. The subcellular distribution of Cr in both roots and stems was predominantly in the cell wall and residues (T1), followed by the cytoplasm (T4). Partial least squares path model (PLS-PM) was used for quantifying the effect of biochar on the form changes and subcellular detoxification of Cr from soil to roots and stems to sub-cells. In soils, biochar reduced the bioavailability of Cr and decreased the transfer of Cr to rye. In plant roots, Cr was distributed mainly as low-toxicity phosphate complexes in cell walls and vacuoles in sub-cells (with the largest path coefficients of 0.90 and -0.91, respectively). In the stems, Cr was distributed mainly as proteins integrated into the cell walls and vacuoles. This was due to the difference in subcellular compartmentalization of detoxification in the roots and stems. These PLS-PM results provide new insights into the entire process of pollutant detoxification in complex environments.

Bidirectional relationship between internalizing symptoms and gastrointestinal problems in youth with Autism Spectrum Disorder.

Many youth with autism spectrum disorder (ASD) experience co-occurring conditions, such as gastrointestinal (GI) problems and internalizing symptoms. However, the relationship among these co-occurring problems is not well-understood. We analyzed parent reports of GI problems and internalizing symptoms of 621 youth with ASD using path models in a structural equation modeling framework. The best-fitting model was a bidirectional model wherein internalizing symptoms, including withdrawn and anxious behavior, were correlated with GI problems, including constipation, diarrhea, nausea, and stomach pain. This study provides a better understanding of the relationship among co-occurring conditions in youth with ASD and should encourage clinicians to consider treatment of underlying internalizing symptoms or GI problems when providing services for individuals with ASD.

But I have no time to read this article! A meta-analytic review of the consequences of employee time management behaviors.

Time management is a beneficial tool for both individuals and their organizations. In this study, we conduct a meta-analytic review of the consequences of employee time management behaviors. Our results suggest that time management is associated with a variety of beneficial employee outcomes such as increased job satisfaction, job performance, and lower levels of stress and burnout. In addition, we found that the relationship between time management and employee outcomes is partially mediated by work-family conflict. Finally, relative weight analyses results indicated that perceived control over time exhibits incremental validity in predicting job satisfaction, job performance, and stress vis a vis conscientiousness. Directions for future research and practical implications of these findings are discussed.

[Remediation Effect and Mechanism of Inorganic Passivators on Cadmium Contaminated Acidic Paddy Soil].

Cadmium (Cd) is one of the main pollutants in acidic paddy fields, and its accumulation in rice (Oryza sativa L.) and subsequent transfer to the food chain is an important environmental issue in China. In our field study, three types of inorganic passivators (silicon-calcium-magnesium-potassium fertilizer (SCMK), calcium magnesium phosphate fertilizer (CMP), and lime (L) at the rate of 750, 1500, and 2250 kg·hm-2, respectively) were applied to acidic paddy soils polluted by the heavy metal Cd in southern Zhejiang province. The objective of this study was to reveal the effects and chemical mechanisms of passivators on soil acidification and Cd accumulation in rice. The field experimental results showed that the three passivators could effectively improve soil acidification and reduce Cd accumulation in rice grains. The application of 2250 kg·hm-2 SCMK, CMP, and L increased soil pH by 0.62, 0.65, and 0.86 units; decreased exchangeable acidity by 67%, 69%, and 78%; and reduced the content of Cd in brown rice by 73%, 68%, and 77%, respectively. The application of 2250 kg·hm-2 SCMK, CMP, and L reduced the content of Cd in brown rice planted on polluted paddy rice fields to lower than 0.2 mg·kg-1, which reached the national food safety standard. Compared with the control, the application of SCMK, CMP, and L significantly (P<0.05) decreased the content of available Cd extracted by DTPA; decreased the contents of weak acid-extractable (F1) and reducible (F2) Cd; and increased the content of residual (F4) Cd. Correlation analyses indicated that Cd content in brown rice was significantly negatively correlated with soil pH and exchangeable cation content and significantly positively correlated with DTPA-Cd, weak acid-extractable (F1) and reducible (F2) Cd, and exchangeable Al contents. The partial least squares path model (PLS-PM) was used to analyze the relationship between the Cd content of brown rice, DTPA-Cd, and various chemical forms of Cd and soil properties. The direct path coefficients of soil exchangeable cations on Cd content in brown rice, available cadmium, and rice yield were -0.566, -0.866, and 0.873, respectively. Soil pH indirectly affected Cd content of brown rice mainly by directly affecting available Cd in soil. Field experiments demonstrated that the three passivators SCMK, CMP, and L were effective technologies for the safe production of rice in acidic paddy soils polluted by Cd. The possible mechanism for passivators reducing the bioavailability of Cd in soil and its accumulation in brown rice contributed to increased exchangeable cations in the soils. These findings could provide a scientific basis for the safe production of rice in acidic paddy soil polluted by heavy metals.

Impulsiveness indirectly affects suicidal ideation through depression and simultaneously moderates the indirect effect: A moderated mediation path model.

Objective: This study aims to investigate the indirect effect of impulsiveness on suicidal ideation through depression and the moderating effect of impulsiveness on the indirect effect in an integrated path model. Methods: Self-rating depression scale (SDS), Barratt impulsiveness scale-11th version (BIS-11), and self-rating idea of suicide scale (SIOSS) were applied. A moderated mediation path model was established including impulsiveness, depression, and suicidal ideation as observed variables. Results: The main results revealed that the moderated mediation path model fit well in describing the relationships among impulsiveness, depression, and suicidal ideation. The indirect effect of impulsiveness mediated by depression and the moderating effect of impulsiveness on suicidal ideation was significant. Multiple comparisons showed that the indirect effects under different conditions of impulsiveness had statistical differences. The higher the impulsiveness was, the stronger the predictive effect of depression on suicidal ideation was. Conclusions: The present study confirms that people who have impulsive traits are riskier to generate suicidal thoughts because they are more likely to suffer from depression and that people who are depressive have even higher risk to develop suicidal thoughts when they simultaneously have impulsive traits. In clinical and health care work, when considering depression to prevent suicidal ideation, impulsiveness needs to be monitored throughout the process of premorbid and onset stages of depression.

Nanoparticle transport and deposition in a heterogeneous human lung airway tree: An efficient one path model for CFD simulations.

Understanding nano-particle inhalation in human lung airways helps targeted drug delivery for treating lung diseases. A wide range of numerical models have been developed to analyse nano-particle transport and deposition (TD) in different parts of airways. However, a precise understanding of nano-particle TD in large-scale airways is still unavailable in the literature. This study developed an efficient one-path numerical model for simulating nano-particle TD in large-scale lung airway models. This first-ever one-path numerical approach simulates airflow and nano-particle TD in generations 0-11 of the human lung, accounting for 93% of the whole airway length. The one-path model enables the simulation of particle TD in many generations of airways with an affordable time. The particle TD of 5 nm, 10 nm and 20 nm particles is simulated at inhalation flow rates for two different physical activities: resting and moderate activity. It is found that particle deposition efficiency of 5 nm particles is 28.94% higher than 20 nm particles because of the higher dispersion capacity. It is further proved that the diffusion mechanism dominates the particle TD in generations 0-11. The deposition efficiency decreases with the increase of generation number irrespective of the flow rate and particle size. The effects of the particle size and flow rate on the escaping rate of each generation are opposite to the corresponding effects on the deposition rate. The quantified deposition and escaping rates at generations 0-11 provide valuable guidelines for drug delivery in human lungs.

A novel greedy adaptive ant colony algorithm for shortest path of irrigation groups.

With the full-scale implementation of facility agriculture, the laying of a water distribution network (WDN) on farmland plays an important role in irrigating crops. Especially in large areas of farmland, with the parameters of moisture sensors, the staff can divide the WDN into several irrigation groups according to the soil moisture conditions in each area and irrigate them in turn, so that irrigation can be carried out quickly and efficiently while meeting the demand for irrigation. However, the efficiency of irrigation is directly related to the pipe length of each irrigation group of the WDN. Obtaining the shortest total length of irrigation groups is a path optimization problem. In this paper, a grouped irrigation path model is designed, and a new greedy adaptive ant colony algorithm (GAACO) is proposed to shorten the total length of irrigation groups. To verify the effectiveness of GAACO, we compare it with simple modified particle swarm optimization (SMPSO), chaos-directed genetic algorithms (CDGA) and self-adaptive ant colony optimization (SACO), which are currently applied to the path problem. The simulation results show that GAACO can effectively shorten the total path of the irrigation group for all cases from 30 to 100 water-demanding nodes and has the fastest convergence speed compared to SMPSO, CDGA and SACO. As a result, GAACO can be applied to the shortest pipeline path problem for irrigation of farmland groups.

Longitudinal Investigations of Autoregressive Cross-Lagged Path Models Among Internet Use, Executive Function Problems, and Maternal Control in Young Korean Children.

Excessive Internet use is related to behavioral and cognitive dysfunctions, but little is known about the relationship between them in young elementary school children. This study examined the longitudinal relationship between children's Internet use for entertainment purposes, executive function problems, and maternal control. Differences by children's Internet addiction status in their associations were also examined. Data from Wave 9 (2016) to Wave 11 (2018) of 1,463 children and mothers who participated in the Panel Study on Korean Children (PSKC) were used. The children's ages were 8 (grade 2), 9 (grade 3), and 10 years (grade 4) at Waves 9, 10, and 11, respectively. Associations between the variables were analyzed using autoregressive cross-lagged model estimations and multi-group analysis. The results showed the longitudinal stability of each of children's Internet use, executive function problems, and maternal control over the 3 years. Mutual associations between maternal control and children's Internet use were found especially in the low-risk group. In addition, children's executive function problems positively predicted Internet use, and negative associations from executive function problems to maternal control were significant over the years. However, some of these associations were significant only in the high-risk group. Discussions have focused on the protective role of maternal control and cognitive intervention, which could reduce children's excessive Internet use.

Decipher the molecular descriptors and mechanisms controlling sulfonamide adsorption onto mesoporous carbon: Density functional theory calculation and partial least-squares path modeling.

Mesoporous carbons (MCs) exhibit excellent removal efficiencies to various organic chemicals. However, how the properties of chemicals influence the adsorption mechanisms and further determine their adsorption onto MCs are poorly understood. We investigated the adsorption of 22 sulfonamides (SAs) onto four MCs, and further uncovered the major molecular descriptors and adsorption mechanisms influencing the adsorption by density functional theory (DFT) and partial least-squares path modeling (PLS-PM). The results revealed that the excess molar refraction (E), McGowan's molar volume (V), energy of the highest occupied molecular orbital (EHOMO), hardness (H), and most positive net charge on carbon atom (Qc+) were identified as the indirect factors affecting the distribution coefficient (logKD), by influencing the BE(π-π), BE(H), and logKow. BE(π-π) and logKow displayed significant direct impacts on logKD (p < 0.05), while BE(H) showed insignificant direct influences on logKD (p > 0.05). The PLS-PM results indicate the main driving forces for SAs adsorption including π-π interactions, hydrophobic effects, and hydrogen bonding. This study provides a new perspective on revealing the adsorption mechanisms, and the identified factors can be used to develop the quantitative model to further predict the adsorption of SAs onto MCs.

Living and Dead Microorganisms in Mediating Soil Carbon Stocks Under Long-Term Fertilization in a Rice-Wheat Rotation.

Although soil microorganism is an active area of research, we are still in the early stages of understanding how living microorganisms influence the accumulations of soil microbial residues under different agricultural practices. Based on a 39-year fertilization experiment, we characterized the soil microbiota and correlated their compositions to soil microbial residues, which are indicated by amino sugars under a rice-wheat rotation. In the present study, fertilization regimes and crop season all exerted significant impacts on the compositions of soil microbial communities and their residues, although no significant difference in the microbial residues was found between soil depth (0-10 cm vs. 10-20 cm). Compared within fertilization regimes, the long-term fertilization, especially the application of organic manure, stimulated the accumulations of carbon (C) and nitrogen in soils and microbial residues. Upland soils in wheat season accumulated more microbial residues, particularly in fungal residues, than paddy soils in rice season. Our results suggested that the long-term application of organic manure favored the growth of soil microbial communities, and then increased the contents of microbial residues, particularly in fungal residues, leading to an enlargement of soil C pools. The keystone taxa Pseudaleuria identified by network analysis showed a significantly positive potential in soil C sequestration by increasing the accumulation of fungal residues. Thus, this study revealed the strong and close connections between microbial communities and their residues, and provided evidence about the critical role of keystone taxa in regulating C sequestration.

Environmental factors, bacterial interactions and plant traits jointly regulate epiphytic bacterial community composition of two alpine grassland species.

Epiphytic microbes on the surfaces of leaves and roots can bring substantial benefits or damages to their plant hosts. Although various factors have been proposed for shaping the epiphytic microbial composition, the contributions of environment factors, endogenous microbial taxa interactions, host plant traits, and their interactive effects are poorly understood. Here, we conducted a field investigation along a precipitation gradient and collected leaf and root surface microbes of two alpine plant species for 16S rRNA sequencing. We found that epiphytic bacterial community composition significantly changed along the precipitation gradient through ordination analyses and permutational multivariate analysis of variance. Beneficial bacterial taxa from Caulobacteraceae, Sphingomonadaceae, Comamonadaceae and Rhizobiales were enriched in the high precipitation zones. The stress-tolerant Hymenobacteraceae, Micrococcaceae, and Geodermatophilaceae occurred more frequently in the phyllosphere, and the Thermoleophilia, Thermomicrobiales and Bacillales were enriched in the rhizosphere at the drier sites. Mean annual precipitation was the most important factor regulating the epiphytic bacterial community composition. The direct effect of climate on bacterial community composition was higher in the phyllosphere than in the rhizosphere where joint effects of climate, plant traits and soil properties predominated. Distinct leaf trichome cover and plant height clearly explained the host effect on the phyllosphere bacterial community composition while belowground traits did not explain the host effect well on the rhizosphere bacterial community composition. We detected a significant role of bacterial taxa interactions in shaping microbial communities, where greater negative taxa interactions led to lesser composition changes. Structural equation modeling showed that environmental factors and bacterial interactions substantially contributed to the variation in epiphytic community composition, followed by host plant traits. This study advances our understanding of complex factors affecting alpine epiphytic community assembly and further confirms the role of biotic interactions.

Group exercise membership is associated with forms of social support, exercise identity, and amount of physical activity.

Exploring whether the mechanisms underlying the positive relationship between group exercise and physical activity are forms of social support - emotional, validation, informational, instrumental, and companionship and exercise identity. Participants (n=506; M age = 34.3) completed a 235-item questionnaire assessing physical activity, exercise identity, social support, and other determinants of physical activity. Exploratory path analysis was used to model group exercise membership, forms of social support, exercise identity, and metabolic equivalent (MET) minutes/wk. Women and men had similar yet varying results. For women, group exercise membership was significantly associated with MET-minutes/wk (ß = 0.11) and exercise identity (ß = 0.17). There was a significant association between exercise identity and MET-minutes/wk (ß = 0.38). Women perceived belonging to an exercise group provides emotional (ß = 0.36), validation (ß = 0.25), informational (ß = 0.35), instrumental (ß = 0.19), and companionship (ß = 0.46) support. Validation (ß = 0.11), informational (ß = 0.21), and companionship (B = 0.17) were significantly associated with exercise identity for women. For men, group exercise membership was not significantly associated with MET-minutes/wk or exercise identity. Exercise identity was significantly associated with MET-minutes/wk (ß = 0.46). Men perceived belonging to their group provides emotional (ß = 0.31), validation (ß = 0.32), informational (ß = 0.33), and companionship (ß = 0.34). Validation (ß = 0.22), informational (ß = 0.30), and emotional (ß = 0.23) were significantly associated with exercise identity for men. Belonging to an exercise group is associated with forms of social support that strengthen exercise identity.