Mass Percent Body Fat Research Articles

Application of Bioelectrical Impedance Analysis in Weight Management of Children with Spina Bifida.

Children with spina bifida (SB) face an elevated risk of obesity, which necessitates precise methods for assessing body composition to ensure effective weight management. Conventional measures like BMI are inadequate for this population because of variations in growth patterns and skeletal structure. Bioelectrical impedance analysis (BIA) is a method that offers a clearer picture of body composition, yet its use in children with SB remains underexplored. Conducted on 57 children with SB and 28 healthy controls, with a median age of 11 years, this study evaluated anthropometrics, including BMI and BIA-derived metrics. The Hoffer's scale to assess physical activity was applied in SB children. Results showed that while 32% of SB patients were classified as overweight or obese based on BMI, 62% exhibited high body fat percentage via BIA. Fat-free mass, muscle and fat mass, and fat-to-muscle ratio (FMR) differed significantly compared to the reference group. Non-ambulators showed a higher median body fat mass percentage (25.9% vs. 17.8%, p = 0.01) and FMR (0.92 vs. 0.44, p = 0.003) in comparison to the community walkers. In SB children, BIA-measured fat mass is a better obesity indicator than BMI. Non-ambulatory, SB patients with obesity had the highest FMR values, indicating a higher risk for metabolic syndrome.

Effects of neoagarooligosaccharides on body fat and bowel movement indicators in overweight or obese adults: A randomized, double-blind, placebo-controlled trial

The prevalence of obesity is increasing globally, and dietary fiber supplementation can aid in its treatment. This 12-week randomized, double-blind, placebo-controlled trial examined the effect of Dyne-neoagarooligosaccharides (Dyne-NAOs), hydrolyzed from agar via β-agarase DagA, in overweight or obese adults. Eighty participants were randomly assigned using block randomization (1:1, block size 4) to receive either 15 g of Dyne-NAOs daily or a placebo (maltodextrin). After the intervention, body fat mass (−1.07 kg vs. −0.05 kg; p = 0.015) and body fat percentage (−1.04 % vs. −0.08 %; p = 0.018) were significantly lower in the NAO group than in the placebo group. The Constipation Scoring System (−1.42 vs. −0.06; p = 0.010) and Patient Assessment of Constipation-Symptoms (−3.28 vs. −0.42; p = 0.021), used to assess changes in bowel movements, also showed significant between-group differences. These findings suggest that Dyne-NAOs could be a promising anti-obesity dietary fiber supplement.

The role of body composition in left ventricular remodeling, reverse remodeling, and clinical outcomes for heart failure with mildly reduced ejection fraction: more knowledge to the “obesity paradox”

BackgroundAlthough the “obesity paradox” is comprehensively elucidated in heart failure (HF) with reduced ejection fraction (HFrEF) and HF with preserved ejection fraction (HFpEF), the role of body composition in left ventricular (LV) remodeling, LV reverse remodeling (LVRR), and clinical outcomes is still unclear for HF with mildly reduced ejection fraction (HFmrEF).MethodsOur study is a single-centre, prospective, and echocardiography-based study. Consecutive HFmrEF patients, defined as HF patients with a left ventricular ejection fraction (LVEF) between 40 and 49%, between January 2016 to December 2021 were included. Echocardiography was re-examined at 3-, 6-, and 12-month follow-up to assess the LVRR dynamically. Body mass index (BMI), fat mass, fat-free mass, percent body fat (PBF), CUN-BAE index, and lean mass index (LMI) were adopted as anthropometric parameters in our study to assess body composition. The primary outcome was LVRR, defined as: (1) a reduction higher than 10% in LV end-diastolic diameter index (LVEDDI), or a LVEDDI < 33 mm/m2, (2) an absolute increase of LVEF higher than 10 points compared with baseline echocardiogram, or a follow-up LVEF ≥50%. The secondary outcome was a composite of re-hospitalization for HF or cardiovascular death.ResultsA total of 240 HFmrEF patients were enrolled in our formal analysis. After 1-year follow-up based on echocardiography, 113 (47.1%) patients developed LVRR. Patients with LVRR had higher fat mass (21.7 kg vs. 19.3 kg, P = 0.034) and PBF (28.7% vs. 26.6%, P = 0.047) compared with those without. The negative correlation between anthropometric parameters and baseline LVEDDI was significant (all P < 0.05). HFmrEF patients with higher BMI, fat mass, PBF, CUN-BAE index, and LMI had more pronounced and persistent increase of LVEF and decline in LV mass index (LVMI). Univariable Cox regression analysis revealed that higher BMI (HR 1.042, 95% CI 1.002–1.083, P = 0.037) and fat mass (HR 1.019, 95% CI 1.002–1.036, P = 0.026) were each significantly associated with higher cumulative incidence of LVRR for HFmrEF patients, while this relationship vanished in the adjusted model. Mediation analysis indicated that the association between BMI and fat mass with LVRR was fully mediated by baseline LV dilation. Furthermore, higher fat mass (aHR 0.957, 95% CI 0.917–0.999, P = 0.049) and PBF (aHR 0.963, 95% CI 0.924–0.976, P = 0.043) was independently associated with lower risk of adverse clinical events.ConclusionsBody composition played an important role in the LVRR and clinical outcomes for HFmrEF. For HFmrEF patients, BMI and fat mass was positively associated with the cumulative incidence of LVRR, while higher fat mass and PBF predicted lower risk of adverse clinical events but not LMI.Graphical abstract

Metabolically healthy obesity in adults with X-linked hypophosphatemia.

X-linked hypophosphatemia (XLH) is characterized by increased concentrations of circulating fibroblast growth factor 23 (FGF-23) resulting in phosphate wasting, hypophosphatemia, atypical growth plate and bone matrix mineralization. Epidemiologic studies suggest a relationship between FGF-23, obesity, and metabolic dysfunction. The prevalence of overweight and obesity is high in children with XLH. We aimed to evaluate the prevalence of obesity and metabolic complications in adults with XLH. We conducted a prospective cohort study in adult XLH patients from a single tertiary referral center. The proportion of patients with a BMI >25 kg/m2 was the main outcome measure. Body fat mass percentage (FM%) and adipose tissue surfaces were secondary outcome measures. Glucose homeostasis (plasma glucose and insulin concentrations after fasting and 2 hours after an oral glucose tolerance test) was explored in a subgroup of patients and compared with age-, sex-, and BMI-matched healthy controls. Among 113 evaluated patients, 85 (75%) were female and 110 (97%) carried a PHEX mutation. Sixty-three (56%) patients were overweight or obese, with a median BMI of 25.3 [IQR, 22.7; 29.2] kg/m2. BMI was correlated with FM%, abdominal and thigh subcutaneous and intra-abdominal adipose tissue surfaces. The prevalence of impaired fasting glucose, impaired glucose tolerance, and diabetes was not different between XLH patients and matched controls. The prevalence of overweight and obesity is high among XLH patients and is associated with excess fat mass. However, the prevalence of glucose homeostasis abnormalities is not increased in patients compared to healthy controls, suggesting that metabolically healthy overweight or obesity predominates.

INFLUENCE OF DIETARY HABITS ON BODY COMPOSITION IN LEBANESE ACTIVE UNIVERSITY STUDENTS: A GENDER SPECIFIC ANALYSIS

Problem Statement: The unhealthy lifestyle behaviors that university students face comprising sedentary behaviors are associated with weight gain and obesity in this critical life age. Purpose: The purpose of the study is to explore the effect of dietary habits on body composition parameters in Lebanese Active University Students according to gender. Methods: A sample of 200 students from the Lebanese University, faculty of education, physical Education department were studied. The standardized Dietary questionnaire (Turconi et al., 2003) was used to assess the dietary habits of the participants. Body Composition was assessed using the method of multifrequency bioelectrical analysis. Five body composition parameters were assessed: Body Height, Body Mass, Body mass index, Percentage Body Fat mass, and percentage of Skeletal Muscle mass. Results: Lebanese Physical Education students showed satisfactory results and scored above average in the four sections of the nutrition survey. Regarding gender-based classification, males showed better scores in sections of dietary habits and nutrition knowledge, while females showed better scores in physical activity rated level, and nutrition beliefs. Regarding Body Composition, Lebanese students were found in normal body weight. The multiple regression analysis technique showed that the dietary habits factor has mild to moderate influence on body composition specifically on its three tested dependent variables: BM, BFM, and SMM. Conclusion: Findings support the need from educational and health authorities to develop and evaluate health-promotion and obesity-prevention programs for university communities especially for female gender with regular healthy lifestyle monitoring and standardized assessments.

Lifestyle as a Modulator of the Effects on Fitness of an Integrated Neuromuscular Training in Primary Education.

The objective was to evaluate changes in fitness after an integrated neuromuscular training (INT) intervention in primary school children and to evaluate how lifestyle behaviors and parental education modulate these changes. One hundred and seventy children (7.45 ± 0.34 years; 52% girls) were included. Cardiorespiratory fitness (half-mile run test), a 10 × 5 m shuttle run test, standing broad jump (SBJ), handgrip dynamometer, body mass index (BMI) and fat mass percentage (FM%) were assessed before and after the 3-month intervention (20 min of INT in the physical education class, twice per week). The Mediterranean diet (MD), sleep time and parental education level (PEL) were evaluated by questionnaires, and adherence to physical activity (PA) recommendations was measured with a triaxial accelerometer before the intervention. After the intervention, there were improvements in the 10 × 5 test and the SBJ. Only girls had improvements in the handgrip test, BMI SDS and FM%. After correcting for confounding variables, only BMI was significantly improved whereas strength improved in the participants non-compliant with the PA recommendations or pertaining to families of high PEL. The INT produced improvements in fitness in a brief period and in different subgroups of pupils (inactive and with diverse sociocultural environments).

Differences Between Afro-Caribbean and White Caucasian Olympic Athletes in Plasma Lipids Profile: A Cross-Sectional Single Center Study.

Ethnic and gender differences in plasma lipid composition have been widely reported among the general population, but there are scarce data on athletes. To assess ethnic and gender differences in lipid profile across a large cohort of Olympic athletes practicing different sport disciplines METHODS: We enrolled 1165 Olympic athletes divided into power, endurance, and mixed disciplines according to European Society of Cardiology classification. Sixty-two (5.3%) were Afro-Caribbean. Body composition and fat mass percentage were measured. Blood samples were collected and lipid profile was investigated. Compared to Caucasians, Afro-Caribbeans had better lipid profile characterized by lower LDL (90 ± 25 mg/dL vs. 97.1 ± 26.2 mg/dL, p = 0.032) lower LDL/HDL ratio (1.39 ± 0.5 vs. 1.58 ± 0.6, p = 0.012), lower non-HDL-cholesterol (102.5 ± 27.4 mg/dL vs. 111.5 ± 28.5 mg/dL, p = 0.015) and lower TC/HDL (2.59 ± 0.6 vs. 2.82 ± 0.7, p = 0.010). Female Afro-Caribbeans showed lower TG/HDL ratio (p = 0.045) and TC/HDL ratio (p = 0.028), due to higher HDL (p = 0.005) compared to male Afro-Caribbeans. In Caucasian athletes, females showed even more evident differences with lower TC, LDL, and higher HDL with subsequent lower ratios compared to men. Moreover, endurance Caucasian athletes had lower LDL (p = 0.003) and TG (p = 0.017) plasmatic levels and higher HDL levels compared to non-endurance Caucasian athletes (p< 0.0001) CONCLUSIONS: Ethnicity and gender have a significant influence on plasmatic lipid balance in elite athletes and Afro-Caribbeans have favorable lipid profiles compared to Caucasians. Moreover, endurance sports, particularly in Caucasian athletes, are associated with better lipid profile compared to other type of sports.

Exploring body composition metrics: Comparing percentage body fat, BMI, and body fat mass in college students

Exploring body composition metrics: Comparing percentage body fat, BMI, and body fat mass in college students

Association of dietary total antioxidant capacity with general and abdominal obesity in type 2 diabetes mellitus patients.

The dual existence of Type 2 Diabetes Mellitus (T2DM) and obesity within a single individual may describe a combined adverse health effects, including impaired quality of life and increased risk for cardiovascular diseases (CVDs). Oxidative stress is a contributing factor to the pathogenesis of obesity. Meanwhile, dietary antioxidants may improve the antioxidant defense system and thereby decrease oxidative injury. Dietary total antioxidant capacity (TAC) is usually used to investigate the potential health effects of dietary antioxidant intake on several oxidative stress induced chronic diseases. This study aimed to examine the association of dietary TAC with obesity-related features in T2DM patients. The present study included 254 type 2 diabetes outpatients with a mean (SD) age of 54.52 (7.21) years and mean (SD) diabetes duration of 8.2 (6.4) years. Data on dietary intake was assessed using a validated food frequency questionnaire. Dietary TAC was estimated by ferric reducing antioxidant potential (FRAP) method. Anthropometric, clinical and lifestyle characteristics were all collected. In linear regression analyses, dietary antioxidant capacity was inversely associated with body mass index (β = -0,231; 95% CI, -0,419 to -0,042), waist circumference (β = -0,427; 95% CI, -0,849 to -0,006) and fat mass percentage (β = -0,328; 95% CI, -0,545 to -0,112) independently of the assessed confounding variables. Interestingly, dietary TAC showed positive and significant associations with vitamin A, vitamin C, β-carotene, magnesium, folic acid and iron intakes, after adjusting for age and daily energy intake. Higher intake of dietary TAC was in association with lower indices of general and central obesity in T2DM patients. Therefore, dietary recommendations for counteracting obesity in patients with T2DM should take into account a high dietary TAC.

Relationship between body mass index and fat mass percentage among adolescents from Constantine (Algeria)

Several references based on body mass index (BMI) have been used in Algeria to define adolescent obesity. No studies have been published to assess the diagnostic accuracy of these references. This study aimed to evaluate the sensitivity and specificity of the International Obesity Task Force (IOTF) and Algerian national data based on BMI to detect excess fat in adolescents. A cross sectional study of 257 adolescents aged 16-19 was conducted in Constantine, Algeria. The BMI was calculated from weight and height measurements. The body fat percentage (BF%) was estimated by impedancemetry (BIA). The IOTF and Algerian national data were evaluated for their sensitivity and specificity to detect excess body fat. The BF% thresholds used to define true positives were 25% for boys and 30% for girls. Body mass index was significantly associated with BF% in the whole population (r=0.759). Obesity is more common in girls (p&lt;0.01), regardless of the reference used. The percentage of obesity among adolescents according to the IOTF, Algerian data and BF% was 5.84%, 5.45% and 20.62%, respectively. The obesity rate estimated by BF% was significantly higher (p&lt;0.00001). Sensitivity of the evaluated criteria, IOTF and Algerian data, was high for males (83.3% and 100%, respectively) and low for females (19.2% for both IOTF and Algerian data). Specificity of the two criteria was high for both sexes (100%). Specificity was higher than sensitivity; therefore, the ability of BMI to detect non-obese adolescents was higher than its ability to identify obese adolescents. As BMI is an index of body weight rather than body fat, it can be a source of error. Local data and international references gave the same percentages of obesity. Body mass index is a very specific but less sensitive method to assess increased body adiposity in adolescents. It fails to identify excessive adiposity in a significant percentage of female teenagers. It seems necessary to measure body fat in addition to BMI in adolescent girls. Therefore, it is important to consider body fat mass when determining obesity in order to predict the consequences of obesity, which are mainly due to an increase in fat mass in the body. Key words: Adolescent, Obesity, BMI, Fat mass rate, IOTF, Impedancemetry, Algeria

Effects of 12-week Circuit Exercise Intervention on Blood Pressure, Vascular Function, and Inflammatory Cytokines in Obese Older Women with Sarcopenia.

This study investigates the effects of a 12-week circuit exercise program on blood pressure, vascular function, and inflammatory cytokines in older obese women with sarcopenia. Twenty-eight older obese women with sarcopenia (mean age: 78.2 3.7 years) were randomly divided into an exercise group (EG, n = 14) and a control group (CG, n = 14). The EG participated in a 12-week circuit exercise training regimen, conducted three times weekly, with each session lasting between 45 to 75 minutes (progressively increased over time). The CG was advised to maintain their regular daily routines throughout the intervention period. All dependent variables, including blood pressure, vascular function, and inflammation cytokines, were evaluated pre- and post-intervention. Positive changes were observed in the EG in body composition (body fat mass; p 0.001, body fat percentage; p 0.01, free-fat mass; p 0.01), blood pressure (heart rate; p 0.05, rate pressure product; p 0.01), vascular function (brachial-ankle pulse wave velocity; p 0.05, flow-mediated dilation; p 0.001), and inflammation cytokines (interleukin-6; p 0.05). In the CG, there was an increase in body fat mass (p 0.05) and body fat percentage (p 0.05), while no changes were observed in other variables. The 12-week circuit exercise program significantly reduced blood pressure, improved vascular function, and decreased inflammatory cytokines in obese older women with sarcopenia. However, individual variations in response highlight the need for personalized exercise regimens.

Association of menopausal status with body composition and anthropometric indices in Korean women.

Menopause induces various health problems and is associated with obesity, but the association between menopausal status and obesity is unclear due to several confounding factors, such as aging and reduced physical activity. The objective of this study was to examine the association of menopausal status with anthropometric indices and body composition indices in South Korean women. In this cross-sectional study, a total of 734 subjects (297 postmenopausal women, 437 premenopausal women) from five university hospitals in South Korea were included. A binary logistic regression analysis was performed to examine the association of menopause with anthropometric indices and body composition indices. Height, body mass index, waist-to-height ratio, waist-to-hip ratio, and neck, armpit, chest, rib, waist, iliac, and hip circumferences were associated with menopausal status in the crude analysis, but these associations disappeared in the adjusted models. Among the body composition indices, menopausal status was strongly associated with total body water, skeletal muscle mass, body fat mass, and body fat percentage in the crude analysis. However, the associations with body fat mass and body fat percentage disappeared in the adjusted models. Only the associations with total body water and skeletal muscle mass remained in the adjusted models. Most of the anthropometric indices and body composition indices were not associated with menopausal status, but total body water and skeletal muscle mass were significantly lower in postmenopausal women than in premenopausal women.

Reference values of skeletal muscle mass for children in Nanjing area

Objective: To establish the reference values and growth curves of skeletal muscle mass among children in the Nanjing area. Methods: A cross-sectional study was conducted with children who underwent physical examination at the Department of Child Health Care, Children's Hospital of Nanjing Medical University from 2020 January to 2022 September. Their height, weight, body fat mass and skeletal muscle mass were measured. Body mass index, percentage of body fat mass, percentage of skeletal muscle mass, relative skeletal muscle mass index and the ratio of skeletal muscle to body fat were calculated. The associations between skeletal muscle mass indices and physical measurements index were analyzed through the Spearman correlation test. The Mann-Kendall test was used to assess the trend for skeletal muscle mass. Generalized additive models for location, scale and shape were used to construct percentile reference values and growth curves of male and female skeletal muscle mass indices at different ages. Results: A total of 32 690 children aged 4-14 years were enrolled in this study, including 19 912 boys (60.91%). Skeletal muscle mass, percentage of skeletal muscle mass, relative skeletal muscle mass index and the ratio of skeletal muscle to body fat of boys and girls was 11.10 (8.40, 14.90) and 10.30 (7.90, 13.20) kg, 40.36% (37.01%, 43.13%) and 39.38% (36.43%, 41.88%), 6.70 (6.07, 7.52) and 6.33 (5.79, 7.00), 2.39 (1.46, 3.47) and 2.14 (1.45, 3.00) kg/m2, respectively. Skeletal muscle mass of both boys and girls was all positively associated with weight (r=0.97, 0.96), body mass index (r=0.68, 0.63) and percentage of body fat mass (r=0.40, 0.43) (all P<0.01). The reference values and growth curves showed that the percentage of skeletal muscle mass P50 ranged from 37.75%-44.61% in boys and from 36.22%-40.55% in girls. The relative skeletal muscle mass index P50 ranged from 5.80-9.68 kg/m2 in boys and from 5.57-7.98 kg/m2 in girls. The ratio of skeletal muscle to body fat P50 ranged from 1.86-2.67 in boys and from 1.29-2.41 in girls. There was an increasing trend with age for both boys and girls in the growth of skeletal muscle mass (Z=4.20, 3.75, both Ptrend<0.01), and increased slightly before 9 years of age and then increased rapidly until 14 years of age in both boys and girls. Conclusions: The skeletal muscle mass indices change with age and gender during childhood. Percentile reference values for pediatric skeletal muscle mass indices can be used to evaluate the muscular growth and development in children in the Nanjing area.

Abstract PO5-09-11: Abrupt involution of mouse mammary gland leads to inflammatory systemic changes along with mammary specific metabolic shifts that may enhance risk of breast cancer

Abstract Epidemiological data links higher parity and lack of breastfeeding with increased risk of breast cancer, specifically aggressive triple negative breast cancer (TNBC), and higher mortality rate. Following pregnancy and lactation, breast remodels to near pre-pregnancy stage through apoptotic cell death and adipocyte repopulation process. Long-term breastfeeding and gradual weaning of an infant leads to gradual involution (GI) of the breast, while lack of or abrupt discontinuation of breastfeeding after birth leads to abrupt involution (AI), when rapid and massive cell death takes place. Our studies have shown several precancerous changes, such as increased collagen deposition, inflammation, and hyperplasia in the mammary gland of mice after AI. However, the systemic impact of AI and how this increases risk of breast cancer is yet to be elucidated. Objectives: Our objective is to evaluate the systemic effects that are prompted by the AI mammary gland. We hypothesize that AI leads to marked alteration in lipid metabolism and systemic inflammation that enhances risk for breast cancer. Methods: FVB/n mice (8week old) were paired for breeding. At partum (day 0), dams were randomized to AI or GI cohort and standardized to 6 pups. AI mice had pups removed on day 7 postpartum (ppm) to mimic short-term breastfeeding. For GI mice 3 pups each were removed on day 28 and 31ppm to mimic gradual weaning. Tissues harvested on day 28, 56, and 120 postpartum. Body composition was measured by echo MRI. Glucose tolerance test (GTT) was performed after a 6 hour fast using a 2g/kg glucose intraperitoneal injection. Blood glucose was measured by glucometer. Serum insulin was analyzed by ELISA. HOMA-IR was calculated using blood glucose and serum insulin results. Serum was analyzed using multiplex ELISA by MesoScale Diagnostics. Mammary glands were subjected to untargeted lipidomics. Results: There were no significant differences in body weight, percent body fat or lean mass between AI and GI groups at any time point. However, at day 120 ppm (4 months after partum), we have observed significantly larger amount (1.29-fold increase) of perigonadal adipose tissue (visceral adipose) in AI mice than GI mice (p=0.0112; n=24-38/group). There were no significant differences in blood glucose, serum insulin, HOMA-IR, or GTT results between AI and GI groups at day 120. AI mice had significantly higher levels of cytokines IL-1β (3.1-fold increase, p=0.0417) and KC/GRO (1.5-fold increase, p=0.0196) than GI mice at day 120. At day 28, AI mammary glands had significantly higher amounts of level 3 identified oxidized ceramide containing sphingolipids that were linked to insulin resistance and diabetes. At day 56, GI mammary glands had significantly higher amounts of level 2 and 3 identified metabolites linked to cellular signaling and lipid metabolism. On day 120, there were no significant differences in lipid metabolites between groups. Conclusion: Although histologically GI and AI mammary glands return to near pre-pregnancy state within a month after partum, our data shows specific lipid changes in the AI mammary gland similar to what has been shown in women with TNBC. Furthermore, AI of the mammary gland leads to systemic effects on adiposity and inflammation that could be key to increased breast cancer risk. Further studies along these lines are in progress to understand the whole-body effects of AI and stratify preventive measures for women who cannot breast feed. Significance: Lack of breastfeeding is more prevalent in African American (AA) women and linked to higher risk of developing aggressive TNBC1. Our novel animal models of AI and GI help to link the impact of AI and systemic changes that may enhance breast cancer risk. In particular, we see an increase in visceral adiposity with AI. Understanding this mechanism will help identify strategies to reduce risk in women who are unable or choose not to breastfeed and ultimately help to reduce TNBC and TNBC-related mortality in AA women. Citation Format: Kate Ormiston, Kirti Kaul, Neelam Shinde, Djawed Bennouna, Rachel Kopec, Ramesh Ganju, Sarmila Majumder, Bhuvaneswari Ramaswamy. Abrupt involution of mouse mammary gland leads to inflammatory systemic changes along with mammary specific metabolic shifts that may enhance risk of breast cancer [abstract]. In: Proceedings of the 2023 San Antonio Breast Cancer Symposium; 2023 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2024;84(9 Suppl):Abstract nr PO5-09-11.

Fat loss and muscle gain: The possible role of cortical glutamate in determining the efficacy of physical exercise

BackgroundPhysical exercise is widely acknowledged for its health benefits, but its effectiveness in treating obesity remains contentious due to variability in response. Owing to the roles of glutamate in appetite regulation, food addiction, and impulsivity, this observational cohort-study evaluated medial prefrontal cortex (mPFC) glutamate as a predictor of variability in exercise response, specifically in terms of fat loss and muscle gain. MethodsHealthy non-exercising adult men (n = 21) underwent an 8-week supervised exercise program. Baseline glutamate levels in the mPFC were measured through magnetic resonance spectroscopy. For exercise-dependent changes in body composition (fat and muscle mass), basal metabolic rate (BMR), and blood metabolic biomarkers related to lipid and glucose metabolism, measurements were obtained through bioelectrical impedance and blood sample analyses, respectively. ResultsThe exercise program resulted in significant improvements in body composition, including reductions in percentage body fat mass, body fat mass, and waist-to-hip ratio and an increase in mean muscle mass. Furthermore, BMR and metabolic indicators linked to glucose and lipids exhibited significant changes. Notably, lower baseline glutamate levels were associated with greater loss in percentage body fat mass (r = 0.482, p = 0.027), body fat mass (r = 0.441, p = 0.045), and increase in muscle mass (r = −0.409, p = 0.066, marginal) following the exercise program. ConclusionThese preliminary findings contribute to our understanding of the neurobiology of obesity and emphasize the significance of glutamate in regulating body composition. The results also highlight cortical glutamate as a potential predictor of exercise-induced fat loss and muscle gain.

Phase angle and impedance ratio as meta-inflammation biomarkers after a colon cleansing protocol in a group of overweight young women

Objective. Blood C-reactive protein (CRP) and the electrical bioimpedance spectroscopy (EBIS) variables phase angle (PhA) and impedance ratio (IR) have been proposed as biomarkers of metainflammation in overweight/obesity. CRP involves taking blood samples, while PhA and IR imply a less-than-2-minute-non-invasive procedure. In this study, values for these variables and percent body fat mass (PBFM) were obtained and compared before and immediately after a colon cleansing protocol (CCP), aimed at modulating intestinal microbiota and reducing metainflammation, as dysbiosis and the latter are intrinsically related, as well as along a period of 8 weeks after it. Approach. 20 female volunteers (20.9–24.9 years old) participated: 12 in an overweight group (OG), and 8 in a lean group (LG). The OG was divided in two subgroups (n= 6, each): control (CSG) and experimental (ESG). The ESG underwent a 6-day CCP at week 2, while 5 volunteers in the CSG underwent it at week 9. Main results. Pre/post-CCP mean values for the variables in the OG were: PBFM (34.3/31.3%), CRP (3.7/0.6 mg dl−1), PhA (6.9/7.5°) and IR*10 (0.78/0.77). Calculated R 2 correlation factors among these variables are all above 0.89. The favourable changes first seen in the ESG were still present 8 weeks after the CCP. Significance. (a) the CCP drastically lowers meta-inflammation, (b) EBIS can be used to measure metainflammation, before and after treatment, (c) for microbiota modulation, CCP could be a good alternative to more drastic procedures like faecal microbiota transplantation; (d) reestablishing eubiosis by CCP could be an effective coadjutant in the treatment of overweight young adult women.

Measuring Body Composition and Functional Strength: Implications for the Clinical Assessment of Skeletal Muscle

Skeletal muscle represents the largest single component of the body, comprising up to 50% of total mass in healthy individuals. Body composition assessment has largely focused on overweight and obese individuals, but healthy skeletal muscle is also an important indicator of health and wellbeing. We hypothesized that estimates of lean body mass and empirical measures of functional strength should be directly correlated with one another. In the current study, we estimated body composition using two different field methods. Bioimpedance spectroscopy (BIS) employs 256 frequencies of low energy electrical current to estimate body composition. We used BIS (Impedimed SFB7) to determine percent body fat and fat free mass in physically active volunteers, ranging in age from 18 – 62 years. In addition, we used the Jackson and Pollock 3-site skin fold method to estimate these parameters from the same individuals. We also measured functional strength with a whole body dynamometer to determine mid-thigh pull strength, and a grip dynamometer to assess grip strength (Baseline Evaluation Instruments). Data collected from more than 75 men and women revealed significant correlations between fat-free mass (FFM) and both measures of functional strength. Interestingly, men and women fell along the same trend line, with women exhibiting similar strength for a given FFM. Moreover, functional strength standardized to FFM provides an objective measure of relative strength that was not different between men and women. The American Medical Association released a new policy statement about body mass index (BMI) in June of 2023, highlighting that BMI is an imprecise measure of body composition and recommending that alternative measures, such as more precise measurement of body composition, also be used. Indeed, we found that for individuals with a BMI of less than 30, there was direct relationship between FFM and functional strength. By contrast, percent body fat was not correlated with BMI within this range. We suggest that FFM and functional strength could be used to assess healthy weight, in conjunction with BMI. These measures could also be used to screen for sarcopenia, cachexia, and other conditions associated with significant muscle loss. Skeletal muscle represents an often underappreciated component of health and a more precise assessment of muscle mass and strength should be used as a measure of overall health. This work was supported by a Keenan Award at St. Bonaventure University. This is the full abstract presented at the American Physiology Summit 2024 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.

Treadmill walking economy is not affected by body fat and body mass index in adults.

To determine whether body fat and body mass index (BMI) affect the energy cost of walking (Cw; J/kg/m), ventilation, and gas exchange data from 205 adults (115 females; percent body fat range = 3.0%-52.8%; BMI range = 17.5-43.2 kg/m2) were obtained at rest and during treadmill walking at 1.34 m/s to calculate gross and net Cw. Linear regression was used to assess relationships between body composition indices, Cw, and standing metabolic rate (SMR). Unpaired t-tests were used to assess differences between sex, and one-way ANOVA was used to assess differences by BMI categories: normal weight, <25.0 kg/m2; overweight, 25.0-29.9 km/m2; and obese, ≥30 kg/m2. Net Cw was not related to body fat percent, fat mass, or BMI (all R2 ≤ 0.011). Furthermore, mean net Cw was similar by sex (male: 2.19 ± 0.30 J/kg/m; female: 2.24 ± 0.37 J/kg/m, p = 0.35) and across BMI categories (normal weight: 2.23 ± 0.36 J/kg/m; overweight: 2.18 ± 0.33 J/kg/m; obese: 2.26 ± 0.31, p = 0.54). Gross Cw and SMR were inversely associated with percent body fat, fat mass, and BMI (all R2 between 0.033 and 0.270; all p ≤ 0.008). In conclusion, Net Cw is not influenced by body fat percentage, total body fat, and BMI and does not differ by sex.

A comparative analysis of the physical fitness profile of Korean women's national amateur boxers by weight category.

The purpose of this study was to examine the differences in specific physical fitness of the national amateur women's boxer. The Korean women's national amateur boxers were classified into the lightweight category (LWC, n=21) and middleweight category (MWC, n=13), and body composition (percentage body fat and body mass index) and specific physical fitness (maximal muscle strength, anaerobic power, isokinetic muscle strength, cardiopulmonary endurance) were measured. The Mann-Whitney U-test was conducted to determine the differences in the body composition and specific physical fitness in women's boxers. The percentage body fat (P=0.004) and body mass index (P<0.001) were significantly higher in the LWC compared to MWC. In addition, LWC showed significantly higher isokinetic muscle strength (P<0.001), upper anaerobic mean power (P=0.002), maximal muscle strength (P=0.003), and maximal heart rate at anaerobic threshold (P=0.029), maximal oxygen consumption (P<0.001) and the 20-m shuttle-run exercise (P=0.004) compared to MWC. In conclusion, the body fat percentage and body mass index levels among body composition were significantly higher in the MWC than in the LWC, and the constant muscle strength, maximum muscle strength, and cardiopulmonary endurance levels were significantly higher in the LWC than in the MWC. The results of this study are expected to provide useful data for planning future strategies for efficient and scientific training programs for each weight category.

Combined Aerobic Exercise with Intermittent Fasting Is Effective for Reducing mTOR and Bcl-2 Levels in Obese Females.

The integration of combined aerobic exercise and intermittent fasting (IF) has emerged as a strategy for the prevention and management of obesity, including its associated health issues such as age-related metabolic diseases. This study aimed to examine the potential of combined aerobic exercise and IF as a preventative strategy against cellular senescence by targeting mTOR and Bcl-2 levels in obese females. A total of 30 obese women, aged 23.56 ± 1.83 years, body fat percentage (FAT) 45.21 ± 3.73% (very high category), BMI 30.09 ± 3.74 kg/m2 were recruited and participated in three different types of interventions: intermittent fasting (IF), exercise (EXG), and a combination of intermittent fasting and exercise (IFEXG). The intervention program was carried out 5x/week for 2 weeks. We examined mTOR and Bcl-2 levels using ELISA kits. Statistical analysis used the one-way ANOVA test and continued with Tukey's HSD post hoc test, with a significance level of 5%. The study results showed that a combination of aerobic exercise and IF significantly decreased mTOR levels (-1.26 ± 0.79 ng/mL) compared to the control group (-0.08 ± 1.33 ng/mL; p ≤ 0.05). However, combined aerobic exercise and IF did not affect Bcl-2 levels significantly (-0.07 ± 0.09 ng/mL) compared to the control group (0.01 ± 0.17 ng/mL, p ≥ 0.05). The IF-only group, exercise-only group, and combined group all showed a significant decrease in body weight and fat mass compared to the control group (p ≤ 0.05). However, the combined aerobic exercise and IF program had a significant effect in reducing the total percentage of body fat and fat mass compared to the IF-only group (p ≤ 0.05). Therefore, it was concluded that the combined intermittent fasting and exercise group (IFEXG) undertook the most effective intervention of the three in terms of preventing cellular senescence, as demonstrated by decreases in the mTOR level, body weight, and fat mass. However, the IFEXG did not present reduced Bcl-2 levels.