Total Muscle Research Articles

Effects of Different Blood Flow Restriction Training Modes on Body Composition and Maximal Strength of Untrained Individuals.

The objective of this study was to examine the impacts of absolute cuff pressure blood flow restriction (A-BFR) training and incremental cuff pressure blood flow restriction (I-BFR) training, under equal cuff pressures, on body composition and maximal strength among untrained adults. Additionally, we aimed to compare these effects with those observed in high-load resistance training (HL-RT). Thirty-three adults without prior professional sports or resistance training experience were recruited and randomly assigned to three groups (n = 11 per group) for an 8-week training program, held three times weekly. The A-BFR group trained with a 20% 1RM load and a cuff occlusion pressure set at 190 mmHg. The I-BFR group initiated training with an occlusion pressure of 160 mmHg, which incrementally increased by 20 mmHg every two weeks, with other conditions mirroring those of the A-BFR group. The HL-RT group trained with a 70% 1RM load. All three groups demonstrated a statistically significant improvement in lower-body maximal strength (p < 0.01), with no significant differences observed among the groups (p > 0.05). A notable increase in left-leg muscle mass was seen across all groups (p < 0.05). However, total muscle mass, right-leg muscle mass, fat-free mass, BMI, bone mineral density, and bone mineral content remained relatively unchanged (p > 0.05), with no significant differences among the groups (p > 0.05). Only the HL-RT group exhibited a significant increase in left-leg thigh circumference (p < 0.05), while right-leg thigh circumference remained stable (p > 0.05), with no significant intergroup differences (p > 0.05). While A-BFR and I-BFR did not yield statistically significant differences in overall training outcomes, A-BFR demonstrated a slightly stronger potential. A-BFR and I-BFR achieved comparable gains in muscle strength and improvements in body composition to those seen with HL-RT. However, HL-RT demonstrated more significant improvements in leg circumference.

Association of Computed Tomography Scan-Assessed Body Composition with Immune and PI3K/AKT Pathway Proteins in Distinct Breast Cancer Tumor Components.

This hypothesis-generating study aims to examine the extent to which computed tomography-assessed body composition phenotypes are associated with immune and phosphoinositide 3-kinase (PI3K)/protein kinase B (AKT) signaling pathways in breast tumors. A total of 52 patients with newly diagnosed breast cancer were classified into four body composition types: adequate (lowest two tertiles of total adipose tissue [TAT]) and highest two tertiles of total skeletal muscle [TSM] areas); high adiposity (highest tertile of TAT and highest two tertiles of TSM); low muscle (lowest tertile of TSM and lowest two tertiles of TAT); and high adiposity with low muscle (highest tertile of TAT and lowest tertile of TSM). Immune and PI3K/AKT pathway proteins were profiled in tumor epithelium and the leukocyte-enriched stromal microenvironment using GeoMx (NanoString). Linear mixed models were used to compare log2-transformed protein levels. Compared with the normal type, the low muscle type was associated with higher expression of INPP4B (log2-fold change = 1.14, p = 0.0003, false discovery rate = 0.028). Other significant associations included low muscle type with increased CTLA4 and decreased pan-AKT expression in tumor epithelium, and high adiposity with increased CD3, CD8, CD20, and CD45RO expression in stroma (p < 0.05; false discovery rate > 0.2). With confirmation, body composition can be associated with signaling pathways in distinct components of breast tumors, highlighting the potential utility of body composition in informing tumor biology and therapy efficacies.

Comparative analysis of some multiple sequence alignment tools using Gallus gallus COX1 sequences

Multiple Sequence Alignment (MSA) is an essential method in bioinformatics for detecting conserved sequence regions and deducing evolutionary relationships. However, performance variability exists among MSA tools, and different tools yield varying results depending on the dataset. This study conducts a comparative evaluation of four widely used MSA tools: ClustalW, Clustal Omega, MUSCLE, and MAFFT. The alignment quality and processing efficiency of these tools were assessed using 40 randomly selected Gallus gallus cytochrome c oxidase subunit 1 (COX1) DNA sequences. The findings offer valuable insights into the specific contexts in which these tools may be most effective. MAFFT demonstrated a notable advantage in processing speed, while Clustal Omega and MAFFT excelled in Column Score (CS). For Total Consensus (TC) score, ClustalW and MUSCLE showed superior performance, and Clustal Omega exhibited the highest performance based on Root Mean Square Deviation (RMSD) values. No significant difference was observed between the tools in terms of the Sum-of-Pairs (SP) score. This study serves as a valuable resource for researchers seeking to optimize the use of MSA tools for their specific applications.

Glomerular Filtration of Creatinine: Validation of a Novel Index of Muscle Mass Among Older Adults.

Low muscle mass is common among older adults and associated with poor prognosis. Quantifying muscle mass is challenging in routine clinical practice. We hypothesized that glomerular filtration of creatinine (GFcr) reflects muscle mass, and previously proposed estimated GFcr (eGFcr), as a practical index of muscle mass in older adults. This study investigated whether measured GFcr (mGFcr) and eGFcr are similarly associated with the direct measure of muscle mass, the thigh total muscle lean area (TTMLA). Cross-sectional analysis of a community-based prospective cohort. A total of 794 older adults with measured glomerular filtration rate (mGFR) and TTMLA in the AGES-Reykjavik Study. Measured GFcr, the product of serum creatinine (Scr) and mGFR obtained using plasma iohexol clearance and eGFcr, the product of Scr and estimated glomerular filtration rate using serum cystatin C (Scys). TTMLA measured using computed tomography. Sex-specific Pearson's correlation and linear regression analyses using continuous and categorical mGFcr and eGFcr. Covariates included demographic, behavioral, and clinical variables, and comorbid conditions. The mean age and mGFR were 80.3±4.0 (SD) years and 62.3±16.5 (SD) mL/min/1.73m2, respectively. The lowest sex-specific tertile of mGFcr, compared with the highest tertile, was associated with a 14.6 (95% CI, 11.5-17.6) cm2/1.73m2 lower TTMLA in men, and a 7.9 (95% CI, 5.5-10.2) cm2/1.73m2 lower TTMLA in women. Significant associations were observed between eGFcr and TTMLA. Correlations of eGFcr with TTMLA were generally as strong or stronger than correlations of alternative indices derived from Scr and Scys. Residual confounding by measured and unmeasured variables. These findings support the validity of GFcr as an index of muscle mass among older adults and the use of eGFcr as a practical alternative to mGFcr in the clinical setting. Low muscle mass is common among older adults and is associated with poor clinical outcomes. Quantifying muscle mass is challenging in routine clinical practice. We evaluated whether glomerular filtration of creatinine (GFcr) could serve as an index of muscle mass. We performed a cross-sectional study including 794 older adults who underwent computed tomography for thigh muscle lean area as a directly measured indicator of total body muscle mass. Significant positive associations between thigh muscle lean area and both measured GFcr (serum creatinine [Scr]×measured glomerular filtration rate [GFR]) and estimated GFcr (Scr×estimated GFR based on serum cystatin C [Scys]), a more practical index, were shown. These findings suggest the value of using eGFcr, a simply obtained novel index in the clinical setting, to assess muscle mass among older adults.

Differential Patterns of Brain and Body Aging on MR Imaging

AbstractBackgroundComparative information on how whole‐body organs are linked with age and the brain is lacking.MethodOverall, 7,149 healthy participants from four sites (Mean age 53.06 ± 12.95 years, 18‐97 years; 48% women; 52% men; 38% non‐white) were scanned on 1.5T MR machines with a whole‐body protocol. Whole body sequences utilized in the quantitative analyses were coronal T1 for organ, fat and muscle segmentation. Deep learning with FastSurfer on MPRAGE trained on 134 participants aged 27‐66 and segmented 96 brain regions. Partial correlation analysis was done controlling for sex and total intracranial volume for brain regions and total abdominal organ volume for abdominal organs. Multiple comparisons were accounted for using the Bonferroni method.ResultAge negatively correlated with gray matter (rp = ‐0.38, p = 6.31×10−244) and white matter (rp = ‐0.263, p = 4.03×10−112). Age positively correlated to cerebral ventricle volume (rp = 0.493, p &lt; .001). Increasing age was also inversely correlated with the lobar structural volumes: frontal lobe (rp = ‐0.420 p = 2.70×10−302), temporal lobe (rp = ‐0.378 p = 4.50×10−240), parietal lobe (rp ‐0.373 with p = 2.22×10−233), occipital lobe (rp = ‐0.259; p = 1.58×10−108). Age negatively correlated with AD risk regions: hippocampus (rp = ‐0.288 and p = 9.79×10−136), posterior cingulate (rp = ‐0.338, p = 4.37×10−189), precuneus (rp = ‐0.321, p= 1.44×10−169). Beyond the brain, the kidney and psoas muscle showed significant negative correlations with age (kidney; rp= ‐0.114, p = 1.23×10−211) and the psoas muscle (rp = ‐0.353, p= 1.13×10−208). Strikingly, visceral fat (vfat) was found to have a strong positive correlation with age, (rp = 0.416, p= 8.81×10−297). Subcutaneous fat (sfat), by contrast, showed a null correlation (rp = ‐0.01, p=1.0). Increasing age showed negative correlations with liver volumes (rp = ‐0.226, p = 2.21×10‐82), spleen (rp = ‐0.262, 5.46×10‐112) and total muscle volume (rp = ‐0.317, 3.17×10‐165).ConclusionDifferential patterns of brain and body organ aging may lend insight into how age can increase the risk for common brain disorders in the elderly such as Alzheimer’s.

Genotypic Influences on Actuators of Aerobic Performance in Tactical Athletes.

This study examines genetic variations in the systemic oxygen transport cascade during exhaustive exercise in physically trained tactical athletes. Research goal: To update the information on the distribution of influence of eleven polymorphisms in ten genes, namely ACE (rs1799752), AGT (rs699), MCT1 (rs1049434), HIF1A (rs11549465), COMT (rs4680), CKM (rs8111989), TNC (rs2104772), PTK2 (rs7460 and rs7843014), ACTN3 (rs1815739), and MSTN (rs1805086)-on the connected steps of oxygen transport during aerobic muscle work. 251 young, healthy tactical athletes (including 12 females) with a systematic physical training history underwent exercise tests, including standardized endurance running with a 12.6 kg vest. Key endurance performance metrics were assessed using ergospirometry, blood sampling, and near-infrared spectroscopy of knee and ankle extensor muscles. The influence of gene polymorphisms on the above performance metrics was analyzed using Bayesian analysis of variance. Subjects exhibited good aerobic fitness (maximal oxygen uptake (VO2max): 4.3 ± 0.6 L min-1, peak aerobic power: 3.6 W ± 0.7 W kg-1). Energy supply-related gene polymorphisms rs1799752, rs4680, rs1049434, rs7843014, rs11549465, and rs8111989 did not follow the Hardy-Weinberg equilibrium. Polymorphisms in genes that regulate metabolic and contractile features were strongly associated with variability in oxygen transport and metabolism, such as body mass-related VO2 (rs7843014, rs2104772), cardiac output (rs7460), total muscle hemoglobin content (rs7460, rs4680), oxygen saturation in exercised muscle (rs1049434), and respiration exchange ratio (rs7843014, rs11549465) at first or secondary ventilatory thresholds or VO2max. Moderate influences were found for mass-related power output. The posterior distribution of effects from genetic modulators of aerobic metabolism and muscle contractility mostly confirmed prior opinions in the direction of association. The observed genetic effects of rs4680 and rs1049434 indicate a crucial role of dopamine- and lactate-modulated muscle perfusion and oxygen metabolism during running, suggesting self-selection in Swiss tactical athletes.

Design and Development of Portable Body Composition Analyzer for Children.

The aim of this study was (i) to design and develop a portable BCA device for measuring body composition parameters such as body weight, body fat (BF) %, total body water (TBW), fat-free mass (FFM), muscle mass (MM), and bone mass (BM); (ii) to validate the developed portable BCA with the Tanita MC 980 MA BCA device. For this current study, two hundred healthy and obese subjects, whose ages ranged from 8 to 12 years (8.4 ± 1.7), were considered. The highest percentage difference between the two study groups was found to be in BFat (50.39%), followed by body mass index (BMI) (41.73 kg), FFM (38.32 kg), and MM (37.89 kg), and this was found to be statistically significant. The results obtained from the designed prototype of the body composition analyzer were validated using Tanita MC 980MA BCA. The overall error% was calculated as ±3% for measuring the different body composition parameters. Due to its low standard error and high overall accuracy, the BCA prototype demonstrates the potential to be a dependable instrument for evaluating and tracking the body composition of children.

Accuracy of Fat Mass and Muscle Mass Measured by Bioelectrical Impedance Analysis in Predicting Osteoporosis in Older Adults

Background: Osteoporosis is a prevalent bone disease characterized by reduced bone mineral density (BMD) and increased fracture risk. This study aimed to evaluate the accuracy of fat mass (FM) and muscle mass measured by bioelectrical impedance analysis (BIA) in predicting osteoporosis in older adults. Methods: A cross-sectional study was conducted on 109 outpatients aged 60 years and older. FM parameters (total fat mass, visceral fat level, and fat mass index [FMI]) and muscle mass parameters (total muscle mass, appendicular skeletal muscle mass [ASM], and appendicular skeletal muscle mass index [ASMI]) were measured using BIA. Osteoporosis was diagnosed based on BMD measurements using dual-energy X-ray absorptiometry (DXA). Receiver operating characteristic (ROC) curves were used to determine cut-off points and assess the accuracy of BIA parameters in predicting osteoporosis. Results: The prevalence of osteoporosis was 52.3% (n=57). The optimal cut-off points for predicting osteoporosis were: total fat mass &gt;36.25%, visceral fat level &gt;12.05, FMI &gt;7.82 kg/m2, total muscle mass &lt;37.82 kg, ASM &lt;16.795 kg, and ASMI &lt;6.895 kg/m2. Among the FM parameters, visceral fat level had the highest accuracy (AUC = 60.9%, sensitivity = 64.9%, specificity = 78.8%) while FMI had the lowest (AUC = 53.5%, sensitivity = 56.1%, specificity = 57.7%). For muscle mass parameters, ASM showed the highest accuracy (AUC = 74.0%, sensitivity = 70.2%, specificity = 76.9%). Conclusion: BIA-derived FM and muscle mass parameters, particularly visceral fat level and ASM can be used to predict osteoporosis in older adults with good accuracy. This non-invasive and accessible method may be useful as a screening tool for osteoporosis, especially in settings where DXA is unavailable.

Associations of Muscle-Related Metrics With Respiratory Disease in Chinese Adults: A Prospective Cohort Study.

There is limited evidence about the association of muscle mass, strength and quality with respiratory disease, especially in Chinese populations. We aimed to comprehensively examine such associations and identify better metrics with more clinical and public health relevance. We conducted a prospective cohort study based on data from the second resurvey of the China Kadoorie Biobank (CKB) study in participants with no prevalent respiratory disease or cancer. Arm muscle quality was calculated as the ratio of grip strength to arm muscle mass. Low muscle mass, grip strength and arm muscle quality were defined as the sex-specific lowest quintiles of corresponding variables. Cox proportional hazard models were used to estimate the hazard ratios (HRs) and 95% confidence intervals (CIs) for respiratory disease. In total, 17 510 participants aged 38-88 (65.4% women; mean age 57.8 ± 9.6) were enrolled in 2013-2014 and followed up until 31 December 2018. During a median follow-up of 4.82 years, 1346 participants developed respiratory disease. After adjustment for sociodemographic characteristics, lifestyle factors and medical histories, the elevated HR of respiratory disease was 1.31 (1.14-1.51) for low grip strength and 1.25 (1.09-1.44) for low arm muscle quality. Grip strength and arm muscle quality exhibited a linearly inverse association between respiratory disease (p = 0.137 and 0.102), with each standard deviation (SD) decrease in grip strength and arm muscle quality associated with a 22% (95% CI: 11%-34%) and 14% (95% CI: 7%-22%) increased risk of respiratory disease. No association was found for low total muscle mass index and low appendicular muscle mass index. Low grip strength and arm muscle quality are associated with increased risks of respiratory disease, and they are better muscle-related metrics for identifying adults at high risk of respiratory disease. Chinese adults may need to maintain normal muscle mass, strength and quality to achieve better respiratory health, but this needs to be validated in appropriately designed clinical trials.

Metagenomic Analysis Identifies Sex-Related Gut Microbial Functions and Bacterial Taxa Associated With Skeletal Muscle Mass.

This study aimed to explore the association between gut microbiota functional profiles and skeletal muscle mass, focusing on sex-specific differences in a population under 65 years of age. Stool samples from participants were analysed using metagenomic shotgun sequencing. Skeletal muscle mass and skeletal muscle mass index (SMI) were quantified (SMI [%] = total appendage muscle mass [kg]/body weight [kg] × 100) using bioelectrical impedance analysis. Participants were categorized into SMI quartiles, and associations between gut microbiota, functional profiling and SMI were assessed by sex, adjusting for age, BMI and physical activity. The cohort included 1027 participants (651 men, 376 women). In men, Escherichia coli (log2 fold change 3.08, q = 0.001), Ruminococcus_B gnavus (log2 fold change 2.89, q = 0.014) and Enterocloster sp001517625 (log2 fold change 2.47, q = 0.026) were more abundant in the lowest SMI compared to the highest SMI group. In contrast, Bifidobacterium bifidum (log2 fold change 3.13, q = 0.025) showed higher levels in the second lowest SMI group in women. Microbial pathways associated with amino acid synthesis (MET-SAM-PWY: log2 fold change 0.42; METSYN-PWY: log2 fold change 0.44; SER-GLYSYN-PWY: log2 fold change 0.20; PWY-5347: log2 fold change 0.41; P4-PWY: log2 fold change 0.53), N-acetylneuraminate degradation (log2 fold change 0.43), isoprene biosynthesis (log2 fold change 0.20) and purine nucleotide degradation and salvage (PWY-6353: log2 fold change 0.42; PWY-6608: log2 fold change 0.38; PWY66-409: log2 fold change 0.52; SALVADEHYPOX-PWY: log2 fold change 0.43) were enriched in the lowest SMI in men (q < 0.10). In women, the second lowest SMI group showed enrichment in energy-related pathways, including lactic acid fermentation (ANAEROFRUCAT-PWY: log2 fold change 0.19), pentose phosphate pathway (PENTOSE-P-PWY: log2 fold change 0.30) and carbohydrate degradation (PWY-5484: log2 fold change 0.31; GLYCOLYSIS: log2 fold change 0.29; PWY-6901: log2 fold change 0.27) (q < 0.05). This study highlights sex-specific differences in gut microbiota and functional pathways associated with SMI. These findings suggest that gut microbiota may play a role in muscle health and point toward microbiota-targeted strategies for maintaining muscle mass.

Effects of Carnosine Addition in Low-Fishmeal Feed on the Growth Performance, Muscle Antioxidant Capacity and Flesh Quality of Orange-Spotted Grouper (Epinephelus coioides)

Carnosine is a natural dipeptide made up of L-histidine and β-alanine which is rich in muscle tissues and has multiple physiological functions. The current research aimed to investigate the effects of varied carnosine concentrations in low-fishmeal feed on the growth, muscle antioxidant capacity and flesh quality of orange-spotted grouper. Carnosine was supplemented at doses of 0, 10, 20, 40, 80, 160, and 320 mg/kg in low-fishmeal feed. Seven groups with three tanks of fish (11.4 ± 0.1 g/fish) were allotted one of the diets during the 8-week feeding trial. The growth rate, body protein content, muscle activities of superoxide dismutase and catalase, and muscle adhesiveness showed positive linear response and/or an open upward parabola with increasing carnosine concentrations, with a peak at 160 mg/kg of carnosine. Feed utilization, serum total protein content, gut trypsin activity, muscle glutathione peroxidase, total antioxidant capacity, muscle hardness, gumminess, chewiness and resilience followed the same pattern as the growth rate, reaching a peak at 320 mg/kg of carnosine; while the opposite trend was observed, reaching a minimum at 320 mg/kg for muscle malondialdehyde and 160 mg/kg for muscle liquid and water loss. The results indicated that appropriate carnosine addition could improve growth performance, muscle antioxidant capacity and flesh quality of grouper. The suitable inclusion concentration was estimated to be 195.14 mg/kg to achieve the best specific growth rate.

The role of anti-aging approaches in managing hypogonadism in sedentary older males.

With thirty percent of the world's population not getting enough exercise, Worldwide, physical inactivity ranks as one of the most common causes of premature mortality. Rapid drops in physical activity, decreased mobility, and early morbidity are aging characteristics. As the population over 80 continues to rise, aging raises the danger of age-related illnesses and changes in hormone release. Understanding the aging process is useful in developing pharmacological therapies and identifying therapeutic targets for age-related testosterone deficiency. Therefore, this study's purpose is to present a thorough evaluation of the effects of anti-aging strategies on testosterone levels in older, inactive men. A literature search was completed for clinical and preclinical studies published in English between 2014 and 2024 related to age, sedentary life, testosterone, and anti-aging strategies. A sedentary lifestyle and low testosterone are linked to a vicious cycle. A sedentary lifestyle lowers testosterone levels, which leads to depression, exhaustion, low energy, and weakened bone and muscle strength. These effects exacerbate the detrimental consequences of aging and physical inactivity. Anti-aging techniques can prevent and treat age-related diseases, including calorie restriction, a balanced diet, regular exercise, weight control, diabetes management, and quitting smoking. Regular exercise raises total testosterone, free testosterone, and muscle steroidogenesis. In older men, testosterone replacement treatment increases bone density, cholesterol, protein synthesis, strength, erectile function, sexual desire, and general cognitive performance. However, some studies suggest dehydroepiandrosterone supplementation may provide health improvements without negative effects, potentially reversing arterial aging and reducing cardiovascular disease risk. This article evaluates the prospects for anti-aging procedures to assist in reducing the adverse effects of aging and physical inactivity in men.

Regional Body Composition and Strength, Not Total Body Composition, Are Determinants of Performance in Climbers.

Objective: To compare the body composition of Chilean climbers of different performance levels and to determine the relation between the forearm and upper-trunk lean mass and the handgrip and upper-body traction strength, respectively. Methods: A cross-sectional study was carried out on thirty Chilean male adult climbers (26.1 ± 4.9 y.): nine of intermediate level (L1), eleven advanced (L2), and ten elite (L3). Through dual-energy X-Ray absorptiometry (DXA; Lunar Prodigy®), fat mass percentage (FM%), total lean mass (LM), forearm lean mass (FLM), and upper-trunk lean mass (UTLM) were measured. Total muscle mass (TMM) was also estimated. Handgrip strength (HGS) was measured with a Jamar® dynamometer. Maximum upper-body traction strength (UBTS) was evaluated with a standardized movement. The level of climbing was assessed according to IRCRA rules. Results: No differences in FM%, total LM, UTLM, or TMM between the groups were found. Left and assistant FLM were significantly higher in L3 (p = 0.047 and 0.041, respectively). HGS absolute, relative, and adjusted by FLM were not different between groups. FLM was associated with HGS in all segments (p ≤ 0.001). UBTS absolute values, and as adjusted by TMM, were significantly higher in L3 (p = 0.047 and p = 0.049, respectively). Conclusions: Left and non-dominant forearm lean mass were significantly higher in elite climbers. Handgrip strength was not significantly higher in elite climbers; however, the upper-body traction strength was significantly higher in elite climbers, independent of total or regional muscle mass.

Impact of strength training on reducing risk of fractures in people living with Human Immunodeficiency virus

The progression of HIV and prolonged antiretroviral therapy (ART) lead to secondary changes in patients, such as reduced bone mineral density (BMD), which increases the susceptibility to fractures and, consequently, the associated morbidity and mortality. The study aimed to assess the impact of strength training on the risk of fractures in people living with Human Immunodeficiency Virus (PLHIV). Sixteen HIV-positive men with lipodystrophy syndrome, under ART, aged 40-70 years, inactive for three months, were included. They underwent 12 weeks of strength training (36 sessions) and were evaluated before and after for fracture risk and femoral neck BMD using FRAX (Fracture Risk Assessment) and DXA (Dual-energy X-ray Absorptiometry), respectively, along with body composition. Comparative statistical analyses were conducted. The results showed a reduction in the risk of major fractures by 24.79% (p=0.009) and of femoral neck fractures by 72.85% (p=0.004). There was a significant increase in femoral neck BMD by 11.69% (p=0.001) and in the T-score by 7.94% (p=0.002), inversely correlating with fracture risk. Total muscle mass increased by 3.79% (p=0.011) and lower limb bone mass by 3.55% (p=0.028), positively correlating with BMD and T-score. It was concluded that a short period of training (12 weeks) reduced the risk of fractures in PLHIV. However, further research is needed to support evidence-based clinical practices.

Dynamic Anthropometrics in Pancreatic Cancer: Associations Between Body Composition Changes During Neoadjuvant Therapy and Survival Outcomes After Resection.

Assessment of individual tumor biology and response to systemic therapy in pancreatic ductal adenocarcinoma (PDAC) remains a clinical challenge. The significance of anthropometric (body composition) changes during chemotherapy as a surrogate for tumor biology in the setting of localized PDAC is unknown. A retrospective, single-institution analysis of patients with PDAC who received neoadjuvant therapy (NAT) and pancreatectomy from 2017 to 2021 was performed. Radiologic anthropometric analysis used artificial intelligence-driven software to segment and compute total and sub-compartment muscle area, adipose tissue area, and attenuation values at the level of the L3 vertebra. Kaplan-Meier survival estimates, log-rank tests, and multivariable Cox regression models were used in survival analyses. The inclusion criteria were met by 138 patients. Although decreases in muscle and adipose tissue areas during NAT were predominant, a subset of patients experienced an increase in these compartments. Increases in muscle greater than 5% (hazard ratio [HR], 0.352; 95% confidence interval [CI] 0.135-0.918; p=0.033) and increases in adipose tissue greater than 15% (HR, 0.375; 95% CI 0.144-0.978; p=0.045), were significantly associated with improved survival, whereas loss of visceral fat greater than 15% was detrimental (HR 1.853; CI 1.099-3.124; p=0.021). No significant associations with single time-point anthropometrics were observed. Gains in total muscle and adipose mass were associated with improved pathologic response to systemic therapy and less advanced pathologic tumor stage. Dynamic anthropometric analysis during NAT for PDAC is a stronger prognostic indicator than measurements taken at a single point in time. Repeated anthropometric analysis during preoperative chemotherapy may serve as a biomarker for individual tumor biology and response to therapy.

Evaluating Muscle Mass Changes in Critically Ill Patients: Rehabilitation Outcomes Measured by Ultrasound and Bioelectrical Impedance.

The loss of muscle mass is common in critically ill patients and is associated with poor prognosis, and efforts have been made to mitigate muscle loss through rehabilitation. This study aimed to evaluate changes in muscle mass in critically ill patients following rehabilitation. We enrolled 53 patients expected to stay in the ICU for more than 7 days, dividing them into rehabilitation (15 patients) and no rehabilitation groups (38 patients). Muscle mass was measured using ultrasound and bioelectrical impedance analysis (BIA). Baseline characteristics and comorbidities showed no statistical differences between the two groups. Initial measurements of muscles showed no significant differences between the groups in rectus femoris thickness, total anterior thigh muscle thickness, cross-sectional area, echogenicity, or in-body skeletal muscle mass at baseline and 7 days. However, at 14 days, significant differences emerged. The rehabilitation group had greater rectus femoris thickness (1.42 cm vs. 0.81 cm, p = 0.007) and total anterior thigh muscle thickness (3.79 cm vs. 2.32 cm, p = 0.007) compared to the no rehabilitation group. Additionally, the rehabilitation group experienced a significantly smaller reduction in rectus femoris cross-sectional area (-4.6% vs. -22.8%, p = 0.021). Although survival rates were higher in the rehabilitation group (73.3% vs. 52.6%), this difference was not statistically significant (p = 0.096). Our findings suggest that rehabilitation in critically ill patients is associated with a slower rate of muscle loss, particularly in the cross-sectional area of the rectus femoris muscle, which may be beneficial for patient recovery.

The effectiveness and acceptability of physical activity interventions amongst older adults with lower socioeconomic status: a mixed methods systematic review.

Older adults with lower socioeconomic status are less likely to be physically active than those with higher socioeconomic status. To inform future intervention development, this review explored: [i] how effective are physical activity interventions at increasing levels of physical activity amongst older adults with lower socioeconomic status?; [ii] what factors are associated with the acceptability of physical activity interventions amongst older adults with lower socioeconomic status?; [iii] what are the implications for developing physical activity interventions for older adults with lower socioeconomic status? This mixed methods systematic review followed PRISMA guidelines. MEDLINE, CENTRAL, Embase, Scopus, Web of Science, PsycINFO, CINAHL, ASSIA and Sports Medicine and Education Index were searched up to May 2023, to identify quantitative, qualitative and mixed methods primary research studies measuring the effectiveness of and/or experiences of physical activity interventions for older adults (aged ≥ 65 years) with lower socioeconomic status. No limits on country were applied. Included studies were assessed for methodological quality using the Mixed Methods Appraisal Tool. Results were synthesised using a results-based convergent synthesis approach with narrative synthesis of quantitative findings and thematic synthesis of qualitative findings. Thirty studies were included. Mixed effects were found for the effectiveness of physical activity interventions, with positive effects for increases in utilitarian walking (i.e. for transport) but not for leisure, mixed effects for objectively measured physical activity and no effects for self-reported total physical activity or muscle strengthening and flexibility activities. Engaging in physical activity interventions was perceived as offering many benefits, social familiarity was important to intervention acceptability and interventions were seen as more acceptable when they were compatible with the lifestyles of older adults with lower socioeconomic status. Future development of physical activity interventions for older adults with lower socioeconomic status should foster social connections, emphasise health benefits of physical activity, hold interventions in locations that are accessible and familiar to older adults with lower socioeconomic status, minimise costs to participants, employ individuals who share participant characteristics to lead interventions, and combine physical activity with other activities older adults with lower socioeconomic status already do to make more efficient use of time. PROSPERO CRD42023417312; https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=417312 .

Effect of natural carotenoids obtained from Haematococcus pluvialis, Paracoccus carotinifaciens, and Phaffia rhodozyma on flesh pigmentation and related biochemical mechanisms in Atlantic salmon (Salmo salar L.)

Effect of natural carotenoids obtained from Haematococcus pluvialis, Paracoccus carotinifaciens, and Phaffia rhodozyma on flesh pigmentation and related biochemical mechanisms in Atlantic salmon (Salmo salar L.)

7785 Muscle Strength and Physical Performance Are Closely Related to Muscle Quality Regardless of Muscle Mass or Diabetes Status

Abstract Disclosure: J. Seo: None. I. Jung: None. S. Park: None. D. Lee: None. J. Yu: None. H. Cho: None. K. Kim: None. E. Song: None. K. Kim: None. N. Kim: None. H. Yoo: None. S. Kim: None. K. Choi: None. N. Kim: None. C. Shin: None. Weakness or slowness is essential to define sarcopenia rather than less muscle mass. Myosteatosis is associated with low muscle strength and poor physical performance, and ectopic fat deposition is a characteristic of diabetes (DM). We investigated the association between muscle strength/physical performance and myosteatosis by considering DM status and muscle mass in community-dwelling older adults. A total of 982 subjects (447 men and 535 women) aged 54-83 years in 8th examination of the Korean Genome and Epidemiology Study Ansan cohort participated in this study. Handgrip strength (HSG), 4-m walking velocity (VEL) and 30-Seconds Sit-to-Stand Test (STST) were checked, appendicular skeletal muscle mass (ASM) and total muscle mass (TMM) by DXA were measured. In midthigh CT image, total muscle area (TMA) was measured and categorized into 3 components using Hounsfield Unit (HU): normal-attenuation muscle area (NAMA, 35-100HU), low-attenuation muscle area (LAMA, 0-34HU), and inter/intramuscular adipose tissue (IMAT) area. As muscle quality indices, the NAMA index, LAMA index, and IMAT index were defined by dividing each parameter by TMA. DM was diagnosed by fasting glucose ≥126 mg/dL, 2hr-OGTT glucose ≥200 mg/dL, HbA1c ≥6.5% or anti-diabetic medication. Subjects with DM (38% of total subjects) had higher age and body mass index (BMI) compared to non-DM subjects. Prevalence of low muscle mass (M:&amp;lt;7.0kg/m2, F:&amp;lt;5.4kg/m2 of ASM/height2) was not statistically different by the presence of DM (DM vs non-DM, 11.7% vs 9.7% in men, 3.6% vs 7.6% in women). However, prevalence of low HGS (M:&amp;lt;28kg, F:&amp;lt;18kg) and slow VEL (&amp;lt;1.0m/sec) was higher in DM subjects than non-DM subjects (DM vs non-DM, low HSG: 18.3% vs 5.6% in men, 28.0% vs 17.3% in women, slow VEL: 40.6% vs 30.7% in men, 61.7% vs 46.2% in women). After adjusting for age and BMI, men with DM had lower muscle mass (ASM, ASM/height2,), TMA and NAMA index but higher LAMA index and IMAT index compared to men without DM. Also, men with DM had lower HGS (p=0.001) and poor STST (p=0.008) than men without DM. In women, muscle mass and muscle quality indices were not significantly different with or without DM, but women with DM had worse STST than women without DM (p=0.013). Age and sex adjusted HSG, but not VEL and STST, was positively associated with muscle mass (ASM, ASM/height2, ASM/BMI, and TMM). Age and sex adjusted HSG, VEL, and STST were positively associated with NAMA index and negatively associated with LAMA index and IMAT index regardless of DM. Linear regression analysis revealed that both ASM and NAMA (or LAMA) indices were independent association factors for HGS. Subjects with DM showed a more pronounced decrease in physical performance and muscle strength than a decrease in muscle mass. In this population-based cohort, less myosteatosis was associated with greater muscle strength and better physical performance, regardless of muscle mass or DM status. Presentation: 6/2/2024

Differences in sarcopenia indices in elderly Japanese women and their relationships with obesity classified according to waist circumference, BMI, and body fat percentage

BackgroundSarcopenic obesity (SO) is defined as a decrease in lean body mass and an increase in body fat mass (BFM) due to aging. Detecting SO in elderly women is important from the perspective of extending healthy life expectancy. While various indices of SO are currently used, there is no global consensus regarding diagnostic criteria for SO. This study aimed to examine the relationship between obesity indices (waist circumference (WC), body mass index (BMI), and body fat percentage (BFP)) and sarcopenia indices (total body muscle mass (TBM), appendicular lean mass (ALM), skeletal mass index (SMI)), and physical function (gait speed (GS), handgrip strength (HGS)).MethodsSubjects were 170 community-dwelling healthy elderly women aged 65–79 years (mean: 72.7 ± 5.78 years) who underwent measurements for WC, BMI, and BFP. A WC of ≥ 90cm was defined as the obese group, BMI was determined as weight (kg) divided by height squared (m2) and a cutoff of ≥ 25 kg/m2 was used to define the obesity group. BFM was measured using the bioelectrical impedance analysis (BIA) method and BFP was calculated from body weight and a cutoff of ≥ 30% was used to define the obesity group. TBM and ALM (kg) were measured using the BIA method, ALM (kg) was corrected for height (m2) to obtain SMI (kg/m2). Physical function was assessed by GS and HGS, which were measured by the 5-m walk test and a digital grip strength meter, respectively.ResultsWhen obesity was assessed using BMI, WC and BFP, obese individuals had higher TBM, ALM and SMI, and lower GS among the sarcopenia indicators. HGS did not differ significantly between the non-obese and obese groups.ConclusionOur findings suggest HGS is thought to reflect muscle strength without being affected by obesity indices, suggesting that it may be useful in detecting possible sarcopenia in obese individuals.