Muscle Quality as a Potential Diagnostic Marker of Advanced Liver Fibrosis in Patients with Non-alcoholic Fatty Liver Disease.

Background: Muscle-liver crosstalk plays an important role in the development and progression of non-alcoholic fatty liver disease (NAFLD). The measurement of muscle echo-intensity during ultrasonography is a real-time, non-invasive method of assessing muscle quality. In this retrospective study, we investigated the significance of poor muscle quality (namely, a greater mass of non-contractile tissue, including intramuscular fat) as a risk factor for advanced liver fibrosis and considered whether it may represent a useful tool for the diagnosis of advanced liver fibrosis. Methods: We analyzed data from 307 patients with NAFLD (143 men and 164 women) who visited the University of Tsukuba Hospital between 2017 and 2022. The patients were stratified into the following tertiles of muscle quality according to their muscle echo-intensity on ultrasonography: modest (84.1 arbitrary units [A.U.]), intermediate (97.4 A.U.), and poor (113.6 A.U.). We then investigated the relationships between muscle quality and risk factors for advanced liver fibrosis and calculated appropriate cutoff values. Results: Patients with poor muscle quality showed a significant, 7.6-fold greater risk of liver fibrosis compared to those with modest muscle quality. Receiver operating characteristic curve analysis showed that muscle quality assessment was as accurate as the fibrosis-4 index and NAFLD fibrosis score in screening for liver fibrosis and superior to the assessment of muscle quantity and strength, respectively. Importantly, a muscle echo-intensity of ≥92.4 A.U. may represent a useful marker of advanced liver fibrosis. Conclusion: Muscle quality may represent a useful means of identifying advanced liver fibrosis, and its assessment may become a useful screening tool in daily practice.

Benefit in physical function and quality of life to nonsurgical treatment of varicose veins: Pilot study.

BACKGROUND: Studies on varicose veins have focused its effects on physical function; however, whether nonsurgical treatments alter muscle oxygenation or physical function remains unclear. Moreover, the differences in such functions between individuals with varicose veins and healthy individuals remain unclear. AIM: To investigate changes in physical function and the quality of life (QOL) following nonsurgical treatment of patients with varicose veins and determine the changes in their muscle oxygenation during activity. METHODS: We enrolled 37 participants (those with varicose veins, n = 17; healthy individuals, n = 20). We performed the following measurements pre- and post-nonsurgical treatment in the varicose vein patients and healthy individuals: Calf muscle oxygenation during the two-minute step test, open eyes one-leg stance, 30 s sit-to-stand test, visual analog scale (VAS) for pain, Pittsburgh sleep quality index, physical activity assessment, and QOL assessment. RESULTS: Varicose veins patients and healthy individuals differ in most variables (physical function, sleep quality, and QOL). Varicose veins patients showed significant differences between pre- and post-nonsurgical treatment- results in the 30 sit-to-stand test [14.41 (2.45) to 16.35 (4.11), P = 0.018), two-minute step test [162.29 (25.98) to 170.65 (23.80), P = 0.037], VAS for pain [5.35 (1.90) to 3.88 (1.73), P = 0.004], and QOL [39.34 (19.98) to 26.69 (17.02), P = 0.005]; however, no significant difference was observed for muscle oxygenation. CONCLUSION: Nonsurgical treatment improved lower extremity function and QOL in varicose veins patients, bringing their condition close to that of healthy individuals. Future studies should include patients with severe varicose veins requiring surgery to confirm our findings.

Triglyceride-glucose index is capable of identifying metabolically obese, normal-weight older individuals.

BACKGROUND: The concept of metabolically obese, normal weight (MONW) has emerged to describe individuals with a normal body mass index (BMI) who are at a relatively high risk of chronic diseases. However, BMI itself is a suboptimal index for the assessment of the health risks associated with visceral fat. The triglyceride-glucose (TyG) index is considered to be a reliable and cost-effective marker of insulin resistance. Therefore, in the present study, we aimed to determine the TyG index cut-off values that could be used to define MONW in older people and to determine the usefulness of these values for the prediction of chronic diseases. METHODS: A total of 4,721 participants in the Korea National Health and Nutritional Examination Survey who were ≥ 60 years of age and did not have underweight or obesity were included. MONW was defined using the criteria for metabolic syndrome (MS), and the TyG index was calculated on the basis of the fasting plasma triglyceride and glucose concentrations. Chronic diseases, including T2DM, hypertension, and non-alcoholic fatty liver disease (NAFLD), were diagnosed. RESULTS: The prevalence of MS increased from the lowest to the highest TyG index tertile. The cut-off values of the TyG index for MONW were calculated as 8.88 and 8.80 for males and females, respectively. MONW, defined using these cut-off values, was associated with high odds ratios for NAFLD, T2DM, and hypertension in both males and females. CONCLUSIONS: The TyG index cut-off values calculated in the present study can be used to discriminate individuals with MONW from other older individuals without obesity and to predict the risk of chronic diseases. These findings show that the TyG index is an effective and cost-efficient method of assessing the risk of chronic diseases in people with MONW.

The Triglyceride-Glucose Index is Independently Associated with Chronic Kidney Disease in the Geriatric Population, Regardless of Obesity and Sex.

BACKGROUND: Insulin resistance (IR) negatively affects several risk factors of chronic kidney disease (CKD). This cross-sectional study investigated whether the triglyceride-glucose (TyG) index, which reflects IR, was independently associated with CKD in a geriatric population, regardless of obesity and sex. METHODS: The analysis included 7,326 individuals (2,864 males and 4,462 females) aged ≥60 years. Non-obesity or obesity was evaluated using a body mass index cutoff of 25 kg/m2. The TyG index was calculated as ln [triglyceride concentration (mg/dL)×fasting plasma glucose concentration (mg/dL)]/2. All participants were categorized into three groups according to TyG tertiles. Moderate-to-severe CKD (MSCKD) was defined as an estimated glomerular filtration rate (eGFR) of <45.0 mL/min/1.73 m2. RESULTS: In males and females with or without obesity, a trend test showed a decreasing tendency in the eGFR from the lowest to highest TyG tertiles. Males without obesity and females with obesity in the middle and highest tertiles of the TyG index were 2.342 and 2.393, and were 2.313 and 3.516 times more likely to have MSCKD, respectively. Those with or without obesity in the highest tertile of the TyG index were 1.736 and 2.374 times more likely to have MSCKD, respectively. CONCLUSION: Geriatric populations with an increased TyG index have a high risk of MSCKD regardless of obesity and sex. Our findings suggest that increased IR is associated with CKD in the geriatric population independent of obesity and sex.

Triglyceride-Glucose Index as a Potential Indicator of Sarcopenic Obesity in Older People.

PURPOSE: This population-based cross-sectional study aimed to determine whether the triglyceride-glucose index (TyG index) is associated with sarcopenic obesity (SO) and whether it would be a helpful indicator of SO. METHODS: A total of 3821 participants aged ≥ 60 years were selected for the study group, and 4919 participants aged 20-39 years were included as a reference group. The participants were allocated to sarcopenia, obesity, and SO groups depending on if their body mass index (BMI) was ≥25 kg/m2 and their sarcopenia index was ≤1 standard deviation (SD) lower than the mean of the reference group. The sex-specific differences and trends among the participants were analyzed by using the TyG index tertiles, and appropriate cut-off values of the TyG index for SO were calculated. RESULTS: As the TyG index increased, BMI increased, but the sarcopenia index decreased in both sexes. Males and females in the middle and highest tertiles of the TyG index were 1.775 and 3.369, and they were 1.993 and 3.157 times more likely to have SO, respectively. The cut-off values of the TyG index for SO in males and females were ≥8.72 and 8.67, respectively. CONCLUSION: A high TyG index is positively associated with SO, and the TyG index may be considered a potential indicator of SO.

Use of the Visceral Adiposity Index as an Indicator of Chronic Kidney Disease in Older Adults: Comparison with Body Mass Index.

The visceral adiposity index (VAI) was recently introduced to quantify visceral fat accumulation and dysfunction. This cross-sectional study explored whether the VAI is associated with chronic kidney disease (CKD) in older adults and compared its utility with that of body mass index (BMI) for predicting CKD. In total, 7736 older adults (3479 men and 4257 women) aged ≥ 60 years were divided into normal, mild, and moderate-to-severe CKD groups. Associations of the VAI and BMI with CKD were compared among the groups, and cut-off points for moderate-to-severe CKD (MSCKD) were established. While the VAI could discriminate among all of the groups, the BMI could not. The severity of CKD was more strongly associated with the VAI than BMI. The odds ratios indicated that, in the fully adjusted model, the VAI was a significant predictor of MSCKD in both men and women, while the BMI was a significant predictor only in men. For the VAI, the area under the receiver operating characteristic curve values for men and women were 0.631 (cut-off point: ≥2.993) and 0.588 (≥4.001), compared with 0.555 (≥25.335) and 0.533 (≥24.096) for BMI, respectively. Taken together, the findings suggest that the VAI is associated with CKD and represents a better indicator for the disease than BMI.

The Anthropometric Measure 'A Body Shape Index' May Predict the Risk of Osteoporosis in Middle-Aged and Older Korean People.

A body shape index (ABSI) is a recently introduced index of abdominal adiposity, relative to body mass index and height, and represents an alternative to body mass index and waist circumference. We aimed to determine whether ABSI is associated with osteoporosis and the ability of ABSI to predict osteoporosis, to investigate the relationship between obesity and osteoporosis In total, 6717 Korean participants (3151 men and 3566 women; 63.6 ± 8.5 years) were recruited and placed into the Normal, Osteopenia, or Osteoporosis groups on the basis of the minimum T-scores of the lumbar spine, proximal femur, and femoral neck. The T-scores of each region and ABSI were compared among the groups and odds ratios and cut-off values of ABSI for osteoporosis were calculated. In participants of both sexes, ABSI tended to increase as bone health deteriorated. The men and women in the highest quartile of ABSI were 1.887 and 2.808 times more likely to have osteoporosis, respectively, and the potential ABSI cut-off values for osteoporosis were 0.0813 and 0.0874 for male and female participants, respectively. These findings suggest that augmentation of ABSI and obesity is associated with a higher risk of osteoporosis and that ABSI may predict the risk of osteoporosis.

The A Body Shape Index Might Be a Stronger Predictor of Chronic Kidney Disease Than BMI in a Senior Population.

The A Body Shape Index (ABSI) was recently introduced to quantify abdominal adiposity relative to the body mass index (BMI) and height. This cross-sectional study was performed to explore whether the ABSI is linked to chronic kidney disease (CKD) in older adults and compare the predictive capacity of the ABSI versus BMI for CKD. In total, 7053 people aged ≥ 60 years were divided into normal, mild, and moderate-to-severe CKD groups based on their estimated glomerular filtration rate (eGFR). The correlation of the ABSI with the eGFR and the differences and trends in the ABSI and BMI among the groups were analyzed, and the cutoff points for moderate-to-severe CKD were calculated. The association between the ABSI and CKD was stronger than that between the BMI and CKD. The ABSI had a better capacity to discriminate the CKD stage than did the BMI. The capacity of the ABSI to predict moderate-to-severe CKD was higher than that of the BMI and was more substantial in women than men. The ABSI cutoff points for CKD were ≥0.0822 and 0.0795 in men and women, respectively. In conclusion, the ABSI serves as a better index than the BMI for screening and detecting high-risk individuals with CKD.

Weight-loss-independent benefits of exercise on liver steatosis and stiffness in Japanese men with NAFLD.

BACKGROUND & AIMS: A weight-loss-independent beneficial effect of exercise on non-alcoholic fatty liver disease (NAFLD) management has been reported, but the underlying mechanism is unknown. To help determine this mechanism, the effects of exercise on individual tissues (liver, adipose tissue, and skeletal muscle) were retrospectively studied. METHODS: Data from Japanese obese men with NAFLD in a 3-month exercise regimen were analysed and compared with those in a 3-month dietary restriction program designed to achieve weight loss. The underlying mechanism was studied in a smaller subcohort. RESULTS: Independent of the effect of weight loss, the exercise regimen reduced liver steatosis by 9.5% and liver stiffness by 6.8% per 1% weight loss, and resulted in a 16.4% reduction in FibroScan-AST score. Improvements in these hepatic parameters were closely associated with anthropometric changes (reduction in adipose tissue and preservation of muscle mass), increases in muscle strength (+11.6%), reductions in inflammation and oxidative stress (ferritin: -22.3% and thiobarbituric acid: -12.3%), and changes in organokine concentrations (selenoprotein-P: -11.2%, follistatin: +17.1%, adiponectin: +8.9%, and myostatin: -21.6%) during the exercise regimen. Moreover, the expression of target genes of the transcription factor Nrf2, an oxidative stress sensor, was higher in monocytes, suggesting that Nrf2 is activated. Large amounts of high-intensity exercise were effective at further reducing liver steatosis and potentiating improvements in pathophysiological parameters (liver enzyme activities and organokine profiles). CONCLUSIONS: The weight-loss-independent benefits of exercise include anti-steatotic and anti-stiffness effects in the livers of patients with NAFLD. These benefits seem to be acquired through the modification of inter-organ crosstalk, which is characterised by improvements in organokine imbalance and reductions in inflammation and oxidative stress. LAY SUMMARY: We investigated the effects of exercise on non-alcoholic fatty liver disease (NAFLD) that were not related to weight loss. We found that exercise had considerable weight-loss-independent benefits for the liver through a number of mechanisms. This suggests that exercise is important for NAFLD patients, regardless of whether they lose weight.

An Association between Lower Extremity Function and Cognitive Frailty: A Sample Population from the KFACS Study.

The present study aimed to define the physical function and lipid profile for physical and cognitive frailty in community-dwelling Korean older adults. A total of 229 participants (age = 76.76 ± 3.72 years; body mass index = 24.83 ± 3.15) were classified into four groups: robust, pre-frailty, cognitive decline, and cognitive frailty. An analysis on the four groups was performed to measure their physical and cognitive function, as well as blood biomarkers. The area under (AUC) the receiver operating characteristic curve (ROC) indicated that the 6-min Walk Test (6MWT), Timed Up and Go test (TUG), and Five Times Sit-to-Stand test (FTSS) had the potential to distinguish the capacity of an old adult to predict cognitive frailty. The 6MWT had a higher sensitivity and the TUG and FTSS tests had greater specificity. With cognitive frailty as a categorical variable, cognitive frailty status was a significant predictor of the TUG (odds ratio (OR) 2.897; 95% confidence interval (CI), 1.283-6.541), FTSS (OR 3.337; 95% CI 1.451-7.673), and 6MWT (OR 0.204; 95% CI 0.070-0.591) tests. Our findings indicate that the 6MWT, TUG, and FTSS tests are closely related to cognitive frailty and can provide potential prognostic cutoff points.

Relationships of Fat and Muscle Mass with Chronic Kidney Disease in Older Adults: A Cross-Sectional Pilot Study.

This cross-sectional pilot study aimed to assess the relationships of fat and muscle mass with chronic kidney disease (CKD) in older adults. Serum creatinine concentration was used to measure estimated glomerular filtration rate (mL/min/1.73 m2) in the 236 subjects, who were allocated to three groups: a normal (≥60.0), a mild CKD (45.0-59.9), and a moderate to severe CKD (<45.0) group. The Jonckheere-Terpstra test and multivariate logistic regression were employed to assess body composition trends and the relationships of % fat mass (FM) or % muscle mass index (MMI) with moderate-to-severe CKD. Body weight, fat-free mass, MMI, and %MMI tended to decrease with an increase in the severity of CKD, but the opposite trend was identified for %FM. No relationship with BMI was identified. The participants in the middle-high and highest quartile for %FM were 6.55 and 14.31 times more likely to have moderate to severe CKD. Conversely, the participants in the highest quartile for %MMI were 0.07 times less likely to have moderate to severe CKD. Thus, high fat and low muscle mass may be more strongly associated with CKD than obesity per se.

Cardiorespiratory fitness is strongly linked to metabolic syndrome among physical fitness components: a retrospective cross-sectional study.

BACKGROUND: Maintaining a good level of physical fitness from engaging in regular exercise is important for the treatment and prevention of metabolic syndrome (MetS). However, which components constitutive of physical fitness confer the greatest influence remains controversial. This retrospective cross-sectional study aimed to investigate the association between MetS and physical fitness components including cardiorespiratory fitness, muscle strength, flexibility, and agility and to identify which physical fitness components have the largest influence on MetS. METHODS: A total of 168 Japanese adult males aged 25-64 years were allocated into non-MetS, pre-MetS, and MetS groups according to the criteria recommended by the Japanese Society of Internal Medicine. Anthropometric measurement of body composition by whole-body dual-energy X-ray absorptiometry and measures related to MetS, including waist circumference, triglyceride level, high-density lipoprotein cholesterol level, blood pressure, glucose level, and physical fitness components, were assessed. For evaluation of cardiorespiratory fitness, muscle strength, flexibility, agility, and balance, maximal oxygen consumption (VO2peak) and oxygen uptake at anaerobic threshold (VO2AnT), handgrip strength and vertical jumping, trunk extension and flexion, stepping side to side, and single-leg balance task with the eyes closed were assessed, respectively. RESULTS: A progressive tendency of increasing body weight, body mass index, whole-body lean and fat mass, percentage of whole-body fat mass, trunk lean and fat mass, percentage of trunk fat mass, arm fat mass, waist circumference, triglyceride level, systolic and diastolic blood pressure, and blood glucose level from the non-MetS group to the MetS group was significant (P < 0.05). Conversely, the cardiorespiratory endurance parameters VO2peak and VO2AnT and the high-density lipoprotein cholesterol level showed a progressively decreasing tendency across the groups (P < 0.01). In addition, a VO2peak below 29.84 ml·kg·min-1 (P = 0.028) and VO2AnT below 15.89 ml·kg·min-1 (P = 0.011) were significant risk components for pre-MetS and MetS. However, there was no significant tendency with respect to muscle strength, agility, and flexibility. CONCLUSION: Cardiorespiratory fitness is strongly linked to metabolic syndrome among physical fitness components.

Influences of Resistance versus Aerobic Exercise on Physiological and Physical Fitness Changes in Previously Inactive Men with Obesity: A Prospective, Single-Blinded Randomized Controlled Trial.

PURPOSE: The purpose of this study was to comparatively investigate changes in physiological and physical fitness in previously inactive men with obesity in response to aerobic exercise (AE) or resistance exercise (RE). METHODS: A total of 27 inactive men with obesity, aged 34-60 years, attended a 90-min AE or RE program 3 days/week for 12 weeks. The subjects underwent assessments of energy intake (by a 3-day weighted dietary record), body weight (by a digital scale), body composition (by whole-body dual-energy X-ray absorptiometry), VO2max (by a cycling ergometer), muscle strength (by a Biodex System 3 dynamometer) and blood analysis. RESULTS: There were no significant interactions (P = 0.100~0.730) among energy intake variables. RE led to decreased fat mass (-4.39%, P < 0.05) and improved cardiorespiratory capacity (+11.66%, P < 0.05), as well as increases in lean mass (+2.12%, P < 0.01) and muscle strength variables (+8.41~+11.00%, P < 0.01 for all), without significant weight change. Although AE induced decreases in fat mass (-5.91%, P < 0.05) and weight (-2.28%, P < 0.05) and improved cardiorespiratory capacity (+19.07%, P < 0.01), lean mass and muscle strength variables remained unchanged. RE showed a stronger positive influence than AE on lean mass (P = 0.003) and muscle strength variables (P = 0.001~0.015), and RE and AE had similar influences on weight, fat mass, cardiorespiratory capacity and blood markers. CONCLUSION: It may be an efficient exercise regimen to perform RE first and then utilize AE to maintain the changes that occur in response to RE.

Whole-body vibration for patients with nonalcoholic fatty liver disease: a 6-month prospective study.

Physical exercise has demonstrated benefits for managing nonalcoholic fatty liver disease (NAFLD). However, in daily life maintaining exercise without help may be difficult. A whole-body vibration device (WBV) has been recently introduced as an exercise modality that may be suitable for patients who have difficulty engaging in exercise. We tested WBV in patients with NAFLD and estimated its effectiveness. We studied the effects of a 6-month WBV program on hepatic steatosis and its underlying pathophysiology in 25 patients with NAFLD. Seventeen patients with NAFLD were designated as a control group. After WBV exercise, body weight in the study group decreased by only 2.5% compared with the control group. However, we found significant increases in muscle area (+2.6%) and strength (+20.5%) and decreases in fat mass (-6.8%). The hepatic (-9.9%) and visceral (-6.2%) fat content also significantly decreased (P < 0.05). There was substantial lowering of hepatic stiffness (-15.7%), along with improvements in the levels of inflammatory markers; tumor necrosis factor alpha (-50.9%), adiponectin (+12.0%), ferritin (-33.2%), and high-sensitivity C-reactive protein (-43.0%) (P < 0.05). These results suggest that WBV is an exercise option for patients with NAFLD that is effective, efficient, and convenient.

Association of Foot Structure with the Strength of Muscles that Move the Ankle and Physical Performance.

The human foot plays an important role in supporting body weight, maintaining postural balance, and absorbing ground reaction forces. Although many studies have indicated that a causal relationship exists between foot structure and alterations in lower extremity kinematics, there is little evidence regarding the possible association of foot structure with strength of muscles that move the ankle and physical performance. A total of 67 adult men with a mean age of 51.19 ± 8.82 years participated in this study. Foot structural parameters were assessed using a 3-dimensional foot scanner. Strength of muscles that move the ankle was measured with a dynamometer. Physical performance items, including agility, force, and proprioception, were also measured. We found that all the measured parameters of the length, width, girth, and height of the foot were positively correlated with the strength of plantarflexion, dorsiflexion, eversion, and inversion (r ranged from 0.26 to 0.57; p < .05). Moreover, all or part of the parameters of the length, width, and girth of the foot but not the height and angles of the foot were correlated significantly with vertical jump, stepping forward and backward, and stepping side to side (r ranged from 0.25 to 0.44; p < .05). These findings indicate a weak-to-moderate association between foot structure and the strength of muscles that move the ankle, as well as physical performance. We therefore suggest that a larger foot may have greater muscle strength of the ankle joint and better physical performance.

Mild-to-Moderate Hallux Valgus Does Not Decrease Ankle Muscle Strength in Middle-Aged Japanese Women: A Comparative Study.

Extreme hallux valgus has been documented to be related to lower functional ability and health-related quality of life. It also has a negative effect on foot structure and biomechanical characteristics, which in turn may affect muscle strength in the foot and ankle. Thus, the purposes of this study were to determine whether there is a difference of ankle muscle strength in varied hallux valgus deformities and to investigate correlations between hallux valgus angles and ankle muscle strength. Hallux valgus angles and ankle muscle strength data were collected from 31 middle-aged Japanese women. The hallux valgus angle was measured with a 3-dimensional foot scanner; ankle muscle strength was measured with a dynamometer. Results showed no differences in ankle muscle strength between normal and mild-to-moderate hallux valgus at both 60º/second and 120º/second (p > .05). Unexpectedly, women with mild-to-moderate hallux valgus had a greater value for inversion peak torque per body weight and eversion-to-inversion ratio than those with normal hallux valgus (p = .019 and p = .022) at 120º/second. Furthermore, hallux valgus was correlated with inversion peak torque and peak torque per body weight (r = 0.47; p = .012 and r = 0.50; p = .007) and associated with eversion-to-inversion strength ratio (r = -0.47; p = .012). The findings indicated that mild-to-moderate hallux valgus did not result in a decrease in ankle muscle strength. Conversely, mild-to-moderate hallux valgus had greater ankle inversion strength in middle-aged Japanese women. Further studies are needed to investigate ankle muscle strength in severe hallux valgus deformities.

Increasing Physical Activity Might Be More Effective to Improve Foot Structure and Function Than Weight Reduction in Obese Adults.

Obesity is reported to be an important factor affecting foot structure and function. For obese individuals, weight reduction or increasing weight physical activity could be an effective approach to improve foot structure and function. The present study sought to determine the effect of weight reduction and increasing physical activity on foot structure and function in obese Japanese and to investigate which intervention is more beneficial. The participants were divided into the weight reduction group (n = 30; body mass index 29.0 ± 2.5 kg/m2), with the intervention consisting of dietary modification, and the increasing physical activity group (n = 15; body mass index 28.2 ± 3.1 kg/m2), with the intervention consisting of walking and jogging. A 3-dimensional foot scanner was used to measure the foot anthropometric data with the participants both sitting and standing. The dorsum height declined and the arch stiffness index increased after the weight reduction intervention, and the truncated foot length decreased and the arch stiffness index increased after the increasing physical activity intervention (p <.05). The arch height index showed a downward trend after the weight reduction intervention (p = .060) and an upward trend after the increasing physical activity intervention (p = .069). Moreover, a greater change was found in the increase of the dorsum height and arch height index and decrease of the truncated foot length in the increasing physical activity group than in the weight reduction group (p <.05). These findings suggest that increasing physical activity might be more effective to improve foot structure and function than weight reduction in obese adults.

Does Weight Reduction Affect Foot Structure and the Strength of the Muscles That Move the Ankle in Obese Japanese Adults?

Obesity is considered a major influential factor of foot structure and function. It has been reported to result in detrimental alterations of foot structure indicators and a decrease in muscle strength, which can lower the quality of life and increase the morbidity of obesity. The purpose of the present study was to determine the effect of weight reduction on foot structure and the strength of the muscles that move the ankle in obese adults. A total of 33 obese Japanese participants (mean body mass index 28.49 ± 2.87 kg/m2) without an exercise habit participated in a 12-week dietary modification program. Their foot structure indicators were measured using a 3-dimensional foot scanner, and the strength of the muscles that move the ankle was assessed using a dynamometer. After the dietary modification, the mean body weight reduction was 7.49 ± 4.10 kg (9.38%; 77.82 ± 13.26 kg before and 70.33 ± 11.37 kg after; p <.001). The wide foot indicators, including the forefoot girth, rearfoot width, and instep girth, had decreased significantly (p <.05), and the decreases correlated positively with the weight reduction. Regarding the strength of the muscles that move the ankle, except for dorsiflexion, all the measured peak torque values per body weight had increased significantly (p <.01). These results suggest that the weight reduction induced by a 12-week dietary modification results in thinner feet and increased strength of the muscles that move the ankle.

Changes in muscle strength after diet-induced weight reduction in adult men with obesity: a prospective study.

BACKGROUND AND OBJECTIVE: The benefits of weight reduction for musculoskeletal disorders are well understood. Steep declines in muscle mass following considerable weight reduction can decrease muscle strength and, consequently, physical performance. However, only a limited number of studies have examined the changes in muscle mass and strength in the context of interventional weight reduction programs. Thus, we investigated the influence of muscle mass decrease caused by diet-induced weight reduction on muscle strength in obese men. METHODS: A total of 24 men with obesity (body mass index [BMI]: 29.2 ± 2.6 kg/m2; age: 52.4 ± 10.0 years) attended a 12-week weight reduction program that implemented dietary restrictions. Each participant underwent assessments of body weight (by a digital scale), body composition (by whole-body dual-energy X-ray absorptiometry [DEXA]), and upper and lower extremity muscle strength (by a hand-held dynamometer and a Biodex System 3 dynamometer, respectively) before and after the program. RESULTS: The program led to significant reductions of 10.5% of weight and 6.1% of lower extremity muscle mass. Similarly, lower extremity muscle strength (measured using a Biodex System 3 dynamometer) was significantly decreased (isometric 60° peak torque decreased by 10% and isokinetic 60°/s peak torque decreased by 9.4%); however, the level of body weight-normalized lower extremity muscle strength did not significantly change (increased by +1.2% and +1.4%). The decrease in muscle strength was related to but did not entirely depend on decrease in muscle mass. Although handgrip strength did not significantly differ (-2.2%), the weight-normalized level of this parameter significantly improved (+9.1%). In addition, decrease in the percentage of whole-body fat mass and increase in the percentage of muscle mass index were observed. CONCLUSION: We recommend performing exercise after diet-induced weight reduction to regain muscle mass and strength and improve body weight-normalized lower extremity muscle strength.

High-Intensity Aerobic Exercise Improves Both Hepatic Fat Content and Stiffness in Sedentary Obese Men with Nonalcoholic Fatty Liver Disease.

We compared the effects of 12-week programs of resistance training (RT), high-intensity interval aerobic training (HIAT), and moderate-intensity continuous aerobic training (MICT). The primary goal was to evaluate the therapeutic effects of the exercise modalities for the management of nonalcoholic fatty liver disease (NAFLD). A total of 61 sedentary obese men with NAFLD were randomized into one of the following exercise regimens (RT, HIAT, or MICT). Hepatic fat content was decreased to a similar extent in the RT, HIAT, and MICT groups (-14.3% vs. -13.7% vs. -14.3%) without significant changes in weight and visceral fat. The gene expression levels of fatty acid synthesis were significantly decreased in the subjects' monocytes. Hepatic stiffness was decreased only in the HIAT group (-16.8%). The stiffness change was associated with restored Kupffer cell phagocytic function (+17.8%) and decreased levels of inflammation such as leptin (-13.2%) and ferritin (-14.1%). RT, HIAT, and MICT were equally effective in reducing hepatic fat content, but only HIAT was effective in improving hepatic stiffness and restoring Kupffer cell function. These benefits appeared to be independent of detectable weight and visceral fat reductions; the benefits were acquired through the modulation of in vivo fatty acid metabolism and obesity-related inflammatory conditions.