Thigh Intramuscular Fat Research Articles

Effects of free weight and body mass-based resistance training on thigh muscle size, strength and intramuscular fat in healthy young and middle-aged individuals.

What is the central question of this study? How do free weight resistance training (RT) and body mass-based RT for 8weeks compare for isometric muscular strength, muscle size and intramuscular fat (IMF) content in the quadriceps femoris? What is the main finding and its importance? Free weight and body mass-based RTs could induce muscle hypertrophy; however, decreased IMF content was observed following the body mass-based RT alone. The objective of this study was to investigate the effects of free weight and body mass-based resistance training (RT) on muscle size and thigh intramuscular fat (IMF) in young and middle-aged individuals. Healthy individuals (aged 30-64years) were assigned to either a free weight RT group (n=21) or a body mass-based RT group (n=16). Both groups performed whole-body resistance exercise twice a week for 8weeks. Free weight resistance exercises (squats, bench press, deadlift, dumbbell rows and back range) involved 70% one repetition maximum, with three sets of 8-12 repetitions per exercise. The nine body mass-based resistance exercises (leg raise, squats, rear raise, overhead shoulder mobility exercise, rowing, dips, lunge, single-leg Romanian deadlifts and push-ups) included the maximum possible repetitions per session, which were performed in one or two sets. Mid-thigh magnetic resonance images using the two-point Dixon method were taken pre- and post-training. The muscle cross-sectional area (CSA) and IMF content in the quadriceps femoris were measured from the images. Both the groups showed significantly increased muscle CSA post-training (free weight RT group, P=0.001; body mass-based RT group, P=0.002). IMF content in the body mass-based RT group significantly decreased (P=0.036) but did not significantly change in the free weight RT group (P=0.076). These results suggest that the free weight and body mass-based RTs could induce muscle hypertrophy; however, in healthy young and middle-aged individuals, decreased IMF content was induced following the body mass-based RT alone.

MULTI-SITE MULTI-VENDOR MRI QUANTITATIVE EVALUATION OF KNEE AND THIGH FAT IN ACL RECONSTRUCTION PATIENTS AT 10-YEAR FOLLOW-UP

Purpose: Both subcutaneous fat and thigh muscle fatty infiltration are negatively associated with the progression of osteoarthritis (OA) and post-traumatic OA (PTOA). However, the involvement of knee and thigh fat in PTOA following ACL reconstruction (ACLR) remains under-explored. In this multi-site, multi-vendor MRI study, we investigate associations between knee subcutaneous fat, thigh subcutaneous fat, and thigh intramuscular fat in ACLR legs and contralateral legs.

Abstract 15025: Visceral Adiposity and Muscle Composition in Heart Failure With Preserved Ejection Fraction and Association With Exercise Tolerance

Introduction: Visceral adipose tissue (AT) promotes inflammation and adverse metabolic changes that mediate disease progression in heart failure with preserved ejection fraction (HFpEF). Exercise intolerance is a hallmark of HFpEF, but little is known about its relation to the extent and distribution of AT. We characterized regional AT distribution in HFpEF patients and controls and analyzed associations with comorbidities and exercise tolerance. Methods: MRI was performed to quantify epicardial, liver, abdominal and thigh skeletal muscle AT. We assessed NYHA class, 6-minute walk distance (6MWD), and global well-being score (GWBS). Multivariable linear and logistic regression models were used, adjusted for age, sex, and body surface area. Results: We studied 55 HFpEF patients (41 women, mean age 67) and 33 controls (21 women, mean age 57). Epicardial AT (4.6 vs 3.2mm, p = 0.03), thigh intermuscular fat (11.0 vs 5.0cm 2 , p < 0.01) and liver fat fraction (FF) (6.4% vs 4.1%, p = 0.04) were higher in HFpEF patients than controls. Women with HFpEF had higher abdominal (443.9 vs 297.3 cm 2 , p = 0.03) and thigh (228.6 vs 112.3 cm 2 , p < 0.001) subcutaneous AT than men. Higher thigh intermuscular fat was associated with higher blood pressure (β [SE] 14.1 [3.3], p < 0.001) and diabetes (β [SE] 2.6 [1.1], p = 0.02), and liver FF was associated with chronic kidney disease (β [SE] 1.6 [0.6], p = 0.01). Higher thigh intramuscular fat was associated with both higher NYHA class and shorter 6MWD, and higher thigh intermuscular AT FF was associated with higher NYHA class ( Table ). Higher epicardial AT and liver FF were associated with lower GWBS. Conclusions: HFpEF patients have increased epicardial, liver, and skeletal muscle fat compared to controls out of proportion to their body size, and adiposity was associated with worse exercise intolerance in HFpEF. These results provide the basis for further investigation into regional AT distribution in relation to HFpEF symptoms and pathophysiology.

Thigh intramuscular fat predicts the prognosis in patients in non-ischemic cardiomyopathy with reduced ejection fraction

Abstract Background Skeletal muscle atrophy is an independent prognostic predictor for patients with chronic heart failure, and the concept of sarcopenia is drawing attention. Furthermore, the importance of not only muscle mass but also intramuscular fat (IMF) has been pointed out. However, there is a lack of consensus on the implications of ectopic fat for the prognosis in patients with non-ischemic cardiomyopathy. Purpose We investigated whether ectopic fat in the thigh affects the prognosis with non-ischemic cardiomyopathy. Methods We recruited 105 patients who were diagnosed with non-ischemic cardiomyopathy by cardiac catheterization and echocardiographic date between September 2017 and November 2019. Finally 73 patients with reduced EF (EF 40% or less) enrolled in this prospective study. Functional status was evaluated by using cardiopulmonary exercise test at baseline. All patients were measured quantity of epicardial fat and thigh IMF percentage (%IMF) using computed tomography scan. Demographic, laboratory and echocardiographic date were collected from the patients' medical records. Clinical endpoints were unexpected readmission. Results During the follow-up period 18 patients had adverse events. The %IMF was significantly higher in the group with adverse events than without (5.57±5.70 and 3.02±2.44%, respectively; p<0.01). Spearman correlation coefficient analysis showed a modest correlation between %IMF and lower limb extension strength (Spearman r=−0.280; p=0.0315), but there was no significant correlation between %IMF and exercise tolerance such as anaerobic threshold and peak oxygen uptake. Patients were divided into 2 groups according to the median values of %IMF. Kaplan-Meier analysis demonstrated that events were significantly higher in the high %IMF group (log-rank p=0.033). Multivariate Cox regression analysis adjusted for left ventricular end-diastolic diameter and peak ventricular oxygen consumption found %IMF as an independent factor of adverse events (hazard ratio 1.545; 95% confidential interval 1.151–2.087; p=0.004). Conclusions In non-ischemic cardiomyopathy patients with reduced EF, %IMF may have important adverse consequences such as increased cardiac-related events. Kaplan-Meier curves Funding Acknowledgement Type of funding source: None

Dietary Metabolizable Energy Responses in Yellow-Feathered Broiler Chickens from 29 to 56 d

SUMMARY In this study, the metabolizable energy (ME) requirements were determined for Chinese yellow-feathered chickens aged from 29 to 56 d. In total, 1,200 29-d-old male yellow-feathered broilers were randomly assigned to 5 dietary treatments with 6 replicates each of 40 birds. Birds were fed 5 levels of dietary ME (2,799, 2,897, 2,997, 3,098, and 3,198 kcal ME/kg diet). Broilers that received high-energy diets had a higher (P 0.05), whereas the abdominal fat percentage and thigh intramuscular fat percentage increased significantly. The retention of energy and protein increased (P 0.05) on the energy, protein, and fat contents in the whole body. The plasma concentrations of total cholesterol and total triglyceride were not (P > 0.05) affected by the dietary energy concentration but the plasma concentration of uric acid increased significantly. According to broken-line regression analysis, the recommended dietary ME levels that maximized ADG, optimized FCR, and minimized the deposition of abdominal fat (%) in yellow-feathered broiler chickens aged from 29 to 56 d were 3,198 kcal, 3,213 kcal, and 2,920 kcal ME/kg, respectively.

Muscle fat quantification using magnetic resonance imaging: case-control study of Charcot-Marie-Tooth disease patients and volunteers.

BackgroundThis study aimed to evaluate the potential value of 3D multiple gradient echo Dixon‐based magnetic resonance imaging (MRI) sequence as a tool for thigh intramuscular fat quantification in Charcot–Marie–Tooth disease (CMT) patients.MethodsA prospective comparison study comprising 18 CMT patients and 18 age/sex‐matched volunteers was performed. MRI including 3D multiple gradient echo Dixon‐based imaging was performed for each subject. Region of interest analyses were performed at the upper and lower third of both thighs. The two‐sample t‐test or Wilcoxon rank sum test was used for intergroup comparison of the mean muscle fat fraction. Intraclass correlation coefficients were used to evaluate the interobserver agreement and test–retest reproducibility. Semiquantitive analysis using the Goutallier classification (Grades 0–4) was performed on T1‐weighted images in upper thigh muscles. For Goutallier Grade 0 muscles, comparison of the mean intramuscular fat fraction between volunteers and CMT patients was performed.ResultsThe interobserver agreements were excellent for all measurements (intraclass correlation coefficients > 0.8). Mean muscle fat fractions were significantly higher in all the measured muscles of CMT patients (P < 0.05) except in the adductor magnus in the upper thigh (P = 0.109). Goutallier Grade 0 muscles of the CMT patients showed a significantly higher mean fat fraction compared with that of the volunteers (P < 0.05).Conclusions3D multiple gradient echo Dixon‐based MRI is a reproducible and sensitive technique which can reveal a significant difference in the fat fraction of thigh muscle, including comparison between Goutallier Grade 0 muscles, between CMT patients and volunteers.

Mitochondrial mass and activity as a function of body composition in individuals with spinal cord injury.

Spinal cord injury (SCI) is accompanied by deterioration in body composition and severe muscle atrophy. These changes put individuals at risk for insulin resistance, type II diabetes, and cardiovascular disease. To determine the relationships between skeletal muscle mitochondrial mass, activity, and body composition, 22 men with motor complete SCI were studied. Body composition assessment was performed using dual‐energy X‐ray absorptiometry and magnetic resonance imaging. Skeletal muscle biopsies were obtained from the vastus lateralis muscle to measure citrate synthase (CS) and complex III (CIII) activity. CS activity was inversely related to %body fat (r = −0.57, P = 0.013), %leg fat (r = −0.52, P = 0.027), %trunk fat (r = −0.54, P = 0.020), and %android fat (r = −0.54, P = 0.017). CIII activity was negatively related to %body fat (r = −0.58, P = 0.022) and %leg fat (r = −0.54, P = 0.037). Increased visceral adipose tissue was associated with decreased CS and CIII activity (r = −0.66, P = 0.004; r = −0.60, P = 0.022). Thigh intramuscular fat was also inversely related to both CS and CIII activity (r = −0.56, P = 0.026; r = −0.60, P = 0.024). Conversely, lean mass (r = 0.75, P = 0.0003; r = 0.65, P = 0.008) and thigh muscle cross‐sectional area (CSA; r = 0.82, P = 0.0001; r = 0.84; P = 0.0001) were positively related to mitochondrial parameters. When normalized to thigh muscle CSA, many body composition measurements remained related to CS and CIII activity, suggesting that %fat and lean mass may predict mitochondrial mass and activity independent of muscle size. Finally, individuals with SCI over age 40 had decreased CS and CIII activity (P = 0.009; P = 0.004), suggesting a decrease in mitochondrial health with advanced age. Collectively, these findings suggest that an increase in adipose tissue and decrease in lean mass results in decreased skeletal muscle mitochondrial activity in individuals with chronic SCI.

The effects of raising system on the lipid metabolism and meat quality traits of slow-growing chickens

We investigated the effects of different raising systems on growth performance, lipid deposition and meat quality traits of chickens. The chickens were raised for 28 days and then randomly assigned into three raising systems with similar body weight (BW) as follows: indoor caged, indoor floor pens and free-range system. They were sacrificed and analysed after 112 days. The raising system had no significant effect on BW and daily weight gain (P > 0.05), but had a significant effect on male thigh intramuscular fat (IMF) and female abdominal fat content (PAF) content (P < 0.05). The expression of hepatic fatty acid synthase (FAS) mRNA level in free-range raising system was significantly lower than that of caged indoor raising systems (P < 0.05). The meat quality (ΔpH, drip loss, shear force and fibre traits) was largely affected by the raising system (P < 0.05). In conclusion, the data indicated that the free-range raising system could significantly reduce thigh IMF content and hepatic FAS expression, consequently affecting the meat quality.

The Relationship Of Intramuscular Fat And Glucose Tolerance In Hispanic Women

Hispanic Americans are 1.5 times more likely to develop diabetes than non-Hispanic whites of similar age, and in almost every age group, the prevalence is higher in women than in men. Intramuscular fat (IMF) in the thigh has been related to impaired glucose tolerance (IGT) and physical inactivity which are risk factors for type 2 diabetes. PURPOSE: The objective of this pilot study was to determine whether thigh IMF and aerobic fitness are related to glucose tolerance in Hispanic females. METHODS: Participants were 18 Hispanic women (29.4 ± 8.3 years). T1-weighted magnetic resonance images of the right thigh were analyzed for IMF and muscle cross-sectional area (CSA). Peak oxygen uptake (VO2) during cycle ergometry was assessed, and fasting, 30, 60, and 120-minute glucose levels were measured. Differences between participants with (n=6) or without (n=12) IGT were assessed. Independent t-tests and simple linear regression were performed to assess relationships between IMF and the dependent variables. RESULTS: Participants with IGT had 96 % more intramuscular fat CSA (5.7 ± 3.3 vs 2.9 ± 1.5 cm2, P = 0.028) and a higher percentage of IMF (6.8 ± 3.3 vs 3.2 ± 1.5 %, P = 0.005) than non-IGT participants. Peak VO2 was 33% lower for participants with IGT (P = 0.003). Percent IMF was strongly associated with blood glucose levels for fasting (r2 =.34), 30 (r2 =.49), 60 (r2 =.48), and 120- minutes (r2 =.54) following glucose ingestion. Peak VO2 was associated with percent IMF (P = 0.002) and blood glucose at 30, 60, and 120- minutes after glucose ingestion (P < 0.03). CONCLUSIONS: It appears from these preliminary data that fat within the thigh muscle may be associated with impaired glucose tolerance and cardiorespiratory endurance in Hispanic women. Further work is needed to determine the underlying mechanisms behind these relationships.

Association between low thigh fat and non‐alcoholic fatty liver disease

Some people have a fatty liver despite having low visceral fat and a low body mass index (BMI). We investigated whether fat distribution, especially thigh subcutaneous fat and thigh intramuscular fat, is associated with non-alcoholic fatty liver disease (NAFLD). The patients consisted of 408 men and women. NAFLD was defined by an ultrasound scan and excluded other liver diseases. Visceral, subcutaneous abdominal, intramuscular, and subcutaneous thigh adipose tissue was measured by computed tomography. The frequency of NAFLD decreased over a quartile of thigh fat independently of BMI in the female patients. Additional adjustments for age and visceral fat area did not change the results. This finding was not observed in the male patients. To investigate the relationship between each fat distribution and NAFLD, we performed a logistic regression analysis. Fat distribution was divided into four groups: visceral fat, abdominal subcutaneous fat, thigh subcutaneous fat, and thigh intramuscular fat. All four fat components were chosen as variables for the regression model. Age, BMI, and the homeostasis model assessment (HOMA) index were then adjusted successively. A larger subcutaneous fat area was negatively associated with NAFLD after adjustment for visceral fat and abdominal subcutaneous fat areas in women, but not in men. It did not change even after age adjustment, BMI, and the HOMA index. Low femoral subcutaneous fat amounts were shown to be independently associated with fatty liver disease in women. These results show the importance of accurate measurements of other regional body compositions as well as visceral fat amounts when investigating NAFLD.

Dietary glycemic index and load, measures of glucose metabolism, and body fat distribution in older adults

Recent evidence suggests that the rate of carbohydrate digestion and absorption may influence the development of type 2 diabetes. The aim of this study was to examine associations of dietary glycemic index and glycemic load with predictors of type 2 diabetes in older adults. This study evaluated cross-sectional relations of dietary glycemic index and glycemic load with measures of glucose metabolism and body fat distribution in participants of the Health, Aging and Body Composition Study, a prospective cohort study of adults aged 70-80 y (n = 2248). In men, dietary glycemic index was positively associated with 2-h glucose (P for trend = 0.04) and fasting insulin (P for trend = 0.004), inversely associated with thigh intramuscular fat (P for trend = 0.02), and not significantly associated with fasting glucose, glycated hemoglobin, or visceral abdominal fat. Dietary glycemic load was inversely associated in men with visceral abdominal fat (P for trend = 0.02) and not significantly associated with fasting glucose, 2-h glucose, glycated hemoglobin, fasting insulin, or thigh intramuscular fat. In women, although dietary glycemic index and load were not significantly related to any measures of glucose metabolism or body fat distribution, the association between dietary glycemic index and 2-h glucose was nearly significant (P for trend = 0.06). The findings of this cross-sectional study indicate an association between dietary glycemic index and selected predictors of type 2 diabetes in older adults, particularly in men.

Dietary glycemic index and load, measures of glucose metabolism, and body fat distribution in older adults

Background: Recent evidence suggests that the rate of carbohydrate digestion and absorption may influence the development of type 2 diabetes. Objective: The aim of this study was to examine associations of dietary glycemic index and glycemic load with predictors of type 2 diabetes in older adults. Design: This study evaluated cross-sectional relations of dietary glycemic index and glycemic load with measures of glucose metabolism and body fat distribution in participants of the Health, Aging and Body Composition Study, a prospective cohort study of adults aged 70–80 y (n = 2248). Results: In men, dietary glycemic index was positively associated with 2-h glucose (P for trend = 0.04) and fasting insulin (P for trend = 0.004), inversely associated with thigh intramuscular fat (P for trend = 0.02), and not significantly associated with fasting glucose, glycated hemoglobin, or visceral abdominal fat. Dietary glycemic load was inversely associated in men with visceral abdominal fat (P for trend = 0.02) and not significantly associated with fasting glucose, 2-h glucose, glycated hemoglobin, fasting insulin, or thigh intramuscular fat. In women, although dietary glycemic index and load were not significantly related to any measures of glucose metabolism or body fat distribution, the association between dietary glycemic index and 2-h glucose was nearly significant (P for trend = 0.06). Conclusion: The findings of this cross-sectional study indicate an association between dietary glycemic index and selected predictors of type 2 diabetes in older adults, particularly in men.