Weight Loss Strategies and the Risk of Skeletal Muscle Mass Loss

Glucagon-like peptide-1 receptor agonist-based agents and weight loss composition: Filling the gaps

Excess adiposity is at the root of type 2 diabetes (T2D). Glucagon-like peptide-1 receptor agonists (GLP-1RAs) have emerged as first-line treatments for T2D based on significant weight loss results. The composition of weight loss using most diets consists of <25% fat-free mass (FFM) loss, with the remainder from fat stores. Higher amounts of weight loss (achieved with metabolic bariatric surgery) result in greater reductions in FFM. Our aim was to assess the impact that GLP-1RA-based treatments have on FFM. We analysed studies that reported changes in FFM with the following agents: exenatide, liraglutide, semaglutide, and the dual incretin receptor agonist tirzepatide. We performed an analysis of various weight loss interventions to provide a reference for expected changes in FFM. We evaluated studies using dual-energy X-ray absorptiometry (DXA) for measuring FFM (a crude surrogate for skeletal muscle). In evaluating the composition of weight loss, the percentage lost as fat-free mass (%FFML) was equal to ΔFFM/total weight change. The %FFML using GLP-1RA-based agents was between 20% and 40%. In the 28 clinical trials evaluated, the proportion of FFM loss was highly variable, but the majority reported %FFML exceeding 25%. Our review was limited to small substudies and the use of DXA, which does not measure skeletal muscle mass directly. Since FFM contains a variable amount of muscle (approximately 55%), this indirect measure may explain the heterogeneity in the data. Assessing quantity and quality of skeletal muscle using advanced imaging (magnetic resonance imaging) with functional testing will help fill the gaps in our current understanding.

Effect of a multidisciplinary lifestyle intervention on body composition in people with osteoarthritis: Secondary analysis of the "Plants for Joints" randomized controlled trial

Objective

The Plants for Joints (PFJ) intervention significantly improved pain, stiffness, and physical function, and metabolic outcomes, in people with metabolic syndrome-associated osteoarthritis (MSOA). This secondary analysis investigated its effects on body composition.

Method

In the randomized PFJ study, people with MSOA followed a 16-week intervention based on a whole-food plant-based diet, physical activity, and stress management, or usual care. For this secondary analysis, fat mass, muscle mass, and bone mineral density were measured using dual-energy X-ray absorptiometry (DEXA) for all participants. Additionally, in a subgroup (n ​= ​32), hepatocellular lipid (HCL) content and composition of visceral adipose tissue (VAT) were measured using magnetic resonance spectroscopy (MRS). An intention-to-treat analysis with a linear-mixed model adjusted for baseline values was used to analyse between-group differences.

Results

Of 66 people randomized, 64 (97%) completed the study. The PFJ group experienced significant weight loss (-5.2 ​kg; 95% CI -6.9, -3.6) compared to controls, primarily from fat mass reduction (-3.9 ​kg; 95% CI -5.3 to -2.5). No significant differences were found in lean mass, muscle strength, or bone mineral density between groups. In the subgroup who underwent MRI scans, the PFJ group had a greater reduction in HCL (-6.5%; 95% CI -9.9, 3.0) compared to controls, with no observed differences in VAT composition.

Conclusion

The PFJ multidisciplinary intervention positively impacted clinical and metabolic outcomes, and appears to significantly reduce body fat, including liver fat, while preserving muscle mass and strength.

The Role of Exercise: Physical Fitness Changes Caused by Hypocaloric Diet and Exercise in Men Who Are Overweight

OBJECTIVE

There is evidence showing the effect of hypocaloric diet and increasing physical activity on weight loss. However, the effect of these factors on body composition and functional capacity remains unclear. Also, it is not clear which type of exercise (aerobic, resistance) has effective health benefits for men who are overweight. The aim of this study is to investigate whether a 12-week combined exercise or walking intervention combined with a hypocaloric diet provides improvements in body composition and functional capacity of men who are overweight compared to those who do not exercise.

METHODS

60 healthy adult men who are overweight were randomized and divided into 3 groups: 1: Hypocaloric Diet + Combined Exercise; 2: Hypocaloric Diet + Walking; 3: Hypocaloric Diet. The exercise groups were trained for 12 wk, 3 days a week and 60 min (60 min\3 days\12 wk). Body composition was determined with Bioelectrical Impedance Analysis (BIA) device, strength parameters with MicroFet 2, functional capacity with 6-min walking test.

RESULTS

Improvement was observed in all groups at the end of 12 wk. The greatest improvement was in the combined exercise group. While the values of the combined exercise group increased in Skeletal Muscle Mass, there was a decline in the walking and non-exercising group. Basal Metabolism was maintained in combined exercise, but a decrease occurred in the non-exercising group. Muscle force increased in combined exercise; however, it was maintained in the legs in the walking group. Cardiorespiratory fitness was at best level in walking group, but there was no difference between combined exercise.

CONCLUSIONS

As a result, a hypocaloric diet without an exercise prescription is sufficient to lose weight in the short term (12 wk) at a certain level. But exercise is more important for body composition, weight management and functional capacity. Long-term and in-depth studies should be conducted to interpret the results better.

The impact of weight loss on fat-free mass, muscle, bone and hematopoiesis health: Implications for emerging pharmacotherapies aiming at fat reduction and lean mass preservation

Similar to bariatric surgery, incretin receptor agonists have revolutionized the treatment of obesity, achieving up to 15-25 % weight loss in many patients, i.e., at a rate approaching that achieved with bariatric surgery. However, over 25 % of total weight lost from both surgery and pharmacotherapy typically comes from fat-free mass, including skeletal muscle mass, which is often overlooked and can impair metabolic health and increase the risk of subsequent sarcopenic obesity. Loss of muscle and bone as well as anemia can compromise physical function, metabolic rate, and overall health, especially in older adults. The myostatin-activin-follistatin-inhibin system, originally implicated in reproductive function and subsequently muscle regulation, appears to be crucial for muscle and bone maintenance during weight loss. Activins and myostatin promote muscle degradation, while follistatins inhibit their activity in states of negative energy balance, thereby preserving lean mass. Novel compounds in the pipeline, such as Bimagrumab, Trevogrumab, and Garetosmab-which inhibit activin and myostatin signaling-have demonstrated promise in preventing muscle loss while promoting fat loss. Either alone or combined with incretin receptor agonists, these medications may enhance fat loss while preserving or even increasing muscle and bone mass, offering a potential solution for improving body composition and metabolic health during significant weight loss. Since this dual therapeutic approach could help address the challenges of muscle and bone loss during weight loss, well-designed studies are needed to optimize these strategies and assess long-term benefits. For the time being, considerations like advanced age and prefrailty may affect the choice of suitable candidates in clinical practice for current and emerging anti-obesity medications due to the associated risk of sarcopenia.

Incretin-Based Weight Loss Pharmacotherapy: Can Resistance Exercise Optimize Changes in Body Composition?

This narrative review highlights the degree to which new antiobesity medications based on gut-derived nutrient-stimulated hormones (incretins) cause loss of lean mass, and the importance of resistance exercise to preserve muscle. Glucagon-like peptide 1 receptor agonists (GLP-1RA) induce substantial weight loss in randomized trials, effects that may be enhanced in combination with glucose-dependent insulinotropic polypeptide (GIP) receptor agonists. Liraglutide and semaglutide (GLP-1RA), tirzepatide (GLP-1 and GIP receptor dual agonist), and retatrutide (GLP-1, GIP, and glucagon receptor triple agonist) are peptides with incretin agonist activity that induce ∼15-24% weight loss in adults with overweight and obesity, alongside beneficial impacts on blood pressure, cholesterol, blood glucose, and insulin. However, these agents also cause rapid and significant loss of lean mass (∼10% or ∼6 kg), comparable to a decade or more of aging. Maintaining muscle mass and function as humans age is crucial to avoiding sarcopenia and frailty, which are strongly linked to morbidity and mortality. Studies indicate that supervised resistance exercise training interventions with a duration >10 weeks can elicit large increases in lean mass (∼3 kg) and strength (∼25%) in men and women. After a low-calorie diet, combining aerobic exercise with liraglutide improved weight loss maintenance compared with either alone. Retaining lean mass during incretin therapy could blunt body weight (and fat) regain on cessation of weight loss pharmacotherapy. We propose that tailored resistance exercise training be recommended as an adjunct to incretin therapy to optimize changes in body composition by preserving lean mass while achieving fat loss.

Optimizing the lifestyle of patients with type 2 diabetes mellitus - Systematic review on the effects of combined diet-and-exercise interventions

AIM

To investigate the effects of combined diet-and-exercise interventions in patients with type 2 diabetes mellitus (T2DM).

DATA SYNTHESIS

A systematic literature search was conducted on PubMed, Web of Science, SPORTDiscus and BISp Surf databases (latest update in June 2024). A total of 14706 records was identified. After screening procedures, 11 randomized controlled trials (n = 24 reports) were included. The included studies compared either the effects of a) a combined intervention versus a diet-only intervention or b) different combinations of diet and exercise. The overall quality of the included study reports was moderate (evaluated with the Risk of Bias 2 (RoB2) tool). Effects of adding exercise to a (calorie-restricted) diet were primarily reflected in increased physical fitness/performance. In far fewer cases, additional beneficial effects on glycemic control, number of subjects taking medication, body weight, body composition, or lipid profile were reported. Combined with regular exercise, an energy-restricted low-carbohydrate (LC) diet with either high-fat (HF) or high-protein (HP) contents showed superior effects compared with an energy-matched conventional (CONV) diet in terms of improvements in medication use (HF-LC versus CONV diet), lipids (HF-LC or HP-LC versus CONV diet) or wellbeing (HP-LC versus CONV diet) in some studies.

CONCLUSIONS

Complementing a dietary intervention with regular exercise can have additional health benefits in T2DM, specifically improved physical fitness/performance. LC diets might be superior to other diets when combined with regular exercise. Other diet-and-exercise combinations than those analyzed in this review need to be investigated.

REVIEW REGISTRATION NUMBER

CRD42023458830.

Muscle Strength and Phase Angle Are Potential Markers for the Efficacy of Multidisciplinary Weight-Loss Program in Patients with Sarcopenic Obesity

Background/Objectives: Traditional weight-loss methods often result in the loss of both fat and muscle mass. For individuals with sarcopenic obesity (SO), additional muscle loss can exacerbate sarcopenia, leading to further declines in muscle strength and function, ultimately worsening quality of life. To mitigate this risk, weight-loss strategies should emphasize the preservation and building of muscle mass through adequate protein intake and tailored resistance training. This study aimed to evaluate changes in SO status following a 4-week multidisciplinary weight-loss intervention program in hospitalized patients with obesity. Methods: This study included adult patients with obesity (BMI > 30 kg/m2, aged 18-90 years). The SO diagnosis was performed using the handgrip strength (HGS) test and skeletal muscle mass (SMM) by bioelectrical impedance analysis (BIA) according to ESPEN/EASO-2022 guidelines. Results: A total of 2004 patients were enrolled, 64.8% female, with a mean age of 56 (±14) years and a BMI of 40.7 (±6.48) kg/m2. SO was present in 9.38% (188 patients) at baseline. At discharge, 80 patients (42.55%) were no longer classified as sarcopenic and showed significant improvements in HGS. The likelihood of resolving SO was not modified in patients with only phase angle (PhA) improvement (p-value = 0.141). Patients with HGS increment had a 65% probability to be No-SO at discharge and this probability, with the concomitant PhA increment, rose to 93% (p-value < 0.0001), indicating that functional changes and good nutrition status are crucial in improvement of SO. Muscle mass (MM) and SMMI remained unchanged in the studied cohort. Conclusions: Improvements in HGS and the PhA are potential markers for the efficacy of weight-loss programs tailored to patients with SO. These findings suggest that specific interventions focusing on these markers could be beneficial in managing SO patients.

Developing an 8-Week, Tele-Education Weight Control and Exercise Programme, and Evaluating Its Effects on Weight and Pain Reduction in Patients With Obesity and Knee Osteoarthritis: A Double-Blinded Randomised Clinical Trial

BACKGROUND

Knee osteoarthritis (OA) is a leading cause of disability among the elderly and is often exacerbated by obesity. Research supports weight loss and exercise therapy as key strategies for managing knee OA-related disability. Concurrently, telemedicine is becoming a popular healthcare approach. This study aimed to develop and evaluate an 8-week tele-education programme's impact on weight control and knee OA outcomes.

METHODS/DESIGN

Participants with knee OA and obesity were included. Baseline data on pain (VAS index), physical activity (GPAQ questionnaire), and quality of life (EQ5D and KOOS questionnaires) were collected. Performance tests, including the 30-second Chair Stand test (30CST) and the Timed Up-and-Go test (TUG), were recorded. Participants were randomly divided into two groups: a control group receiving oral advice on diet and exercise, and an intervention group receiving educational videos on nutrition, lifestyle changes, physical activity, individualised exercises, and psychosocial support. Evaluations were repeated after 8 weeks.

RESULTS

Data from 25 of 30 participants were analysed. In the intervention group, body composition, waist, and abdominal circumference decreased significantly (p < 0.05). The KOOS questionnaire showed significant improvements in pain, activity, and daily tasks (p = 0.00). The EQ5D questionnaire and health satisfaction also showed positive results within the intervention group (p = 0.00) and between groups (p = 0.008). The pain index improved significantly within (p = 0.00) and between groups (p = 0.02). Functional test results were significant within the intervention group (p = 0.00) and between groups (p = 0.017 for 30CST and p = 0.004 for TUG).

CONCLUSION

An 8-week tele-education programme for weight control and exercise therapy in knee OA patients significantly improved body composition, quality of life, and functional performance. Given the costs of obesity and knee OA on both people and the health system, tele-education can be a cost-effective treatment strategy.

Improving multidisciplinary management of patients living with obesity: The evaluation of seated bioimpedance measures and relationship to functional performance following targeted intervention

Management of obesity requires a multidisciplinary approach including physical activity interventions, which have significant impacts on overall health outcomes. Greater levels of lean muscle mass are significantly associated with improved health and reduced risk of comorbidities and should be preserved where possible when undertaking rapid weight loss. This article reports on the physical and functional outcomes achieved during a 12-week intensive multidisciplinary intervention targeting obesity and evaluates correlations between body composition and functional outcomes. We additionally aimed to investigate the test-retest reliability and levels of agreement in body composition measurements using bioimpedance spectroscopy between seated and standing positions. Of the 35 participants included in analysis, significant differences were observed between baseline and post-intervention measures. These included weight loss of 12.6 kg, waist circumference reduction of 10.5 cm, fat mass reduction by 2.9%, muscle mass increase by 1.6%, 54.5 m improvement in the 6-minute walk test and 3.8 rep improvement in the 30-second sit-to-stand test. No significant correlations were observed between physical and functional outcome measures. Excellent test re-test reliability was observed in bioimpedance spectroscopy seated measurements (ICC >.9). Significant differences were observed between seated and standing bioimpedance spectroscopy measurements, however they are regarded as small differences in a clinical setting.

Effects of Semaglutide on Muscle Structure and Function in the SLIM LIVER Study

BACKGROUND

Semaglutide, a GLP-1 receptor agonist, is highly effective for decreasing weight. Concomitant loss of muscle mass often accompanies weight loss and may have consequences on muscle function.

METHODS

This is a secondary analysis from the SLIM LIVER (ACTG A5371) study, a single-arm study of semaglutide in people with HIV (PWH) with metabolic dysfunction-associated steatotic liver disorder (MASLD). Participants received subcutaneous semaglutide for 24 weeks (titrated to 1 mg/week by week 4). Psoas volume and fat fraction were assessed from liver magnetic resonance imaging and physical function by 10-time chair rise test and 4m gait speed. Mean change from baseline to week 24 was estimated with linear regression modeling.

RESULTS

51 PWH enrolled; muscle measures were available from 46 participants. The mean age was 50 (standard deviation [SD] 11) years and BMI 35.5 (5.6) kg/m2, 43% were women, 33% Black, and 39% Hispanic/Latino. Psoas muscle volume decreased by 9.3% (95% confidence interval [CI]: -13.4, -5.2; p<0.001) over 24 weeks but psoas muscle fat did not significantly change (-0.42%, CI: -1.00, 0.17; p=0.16). Chair rise and gait speed had non-significant improvements of 1.27 seconds (CI: -2.7, 0.10) and 0.05 m/sec (CI: -0.01, 0.10), respectively (both p>0.07). The prevalence of slow gait speed (< 1 m/sec) decreased from 63% to 46% (p=0.029).

CONCLUSIONS

In PWH receiving low-dose semaglutide for MASLD, despite decreased psoas muscle volume, there was no significant change in physical function. This suggests that function was maintained despite significant loss of muscle concomitant with weight loss.

Personalized Nutrition Therapy without Weight Loss Counseling Produces Weight Loss in Individuals with Prediabetes Who Are Overweight/Obese: A Randomized Controlled Trial

Obesity stands out as a primary risk factor for diabetes. Attaining healthy weight loss, especially reducing body fat, is important in managing prediabetes and preventing progression to full diabetes and its co-morbidities. This study examined the effects of personalized nutrition therapy (PNT) combined with continuous glucose monitoring (CGM) on body weight and composition in individuals with prediabetes. A total of 30 individuals with prediabetes who were overweight or obese were assigned randomly to either the treatment, observed CGM data plus PNT, or the control group which was blinded to their blood glucose results throughout the study. Both groups were provided with dietary recommendations for calorie intake and macronutrient distribution, coupled with personalized goal setting for glucose control and healthy eating, without any specific emphasis on weight reduction or changes in physical activity. Regular visits were scheduled every 10 days to perform measurements and replace CGMs. Data were analyzed using General Linear Model with repeated measures. Over the 30-day follow-up period, both groups experienced significant reductions in weight and fat mass. The treatment group exhibited two-fold greater reductions in both weight and fat mass, a significant decrease in carbohydrate intake, and a significant increase in time spent on physical activitycompared to the control group. In addition, compliance was notably higher in the treatment group. These findings indicate that overweight or obese individuals with prediabetes can achieve weight loss and improved body composition through personalized education for glucose control, without exclusively emphasizing weight loss as the primary objective. Additionally, the real-time feedback provided by CGM enhances these improvements.

Sex-specific resilience of neocortex to food restriction

Mammals have evolved sex-specific adaptations to reduce energy usage in times of food scarcity. These adaptations are well described for peripheral tissue, though much less is known about how the energy-expensive brain adapts to food restriction, and how such adaptations differ across the sexes. Here, we examined how food restriction impacts energy usage and function in the primary visual cortex (V1) of adult male and female mice. Molecular analysis and RNA sequencing in V1 revealed that in males, but not in females, food restriction significantly modulated canonical, energy-regulating pathways, including pathways associated waith AMP-activated protein kinase, peroxisome proliferator-activated receptor alpha, mammalian target of rapamycin, and oxidative phosphorylation. Moreover, we found that in contrast to males, food restriction in females did not significantly affect V1 ATP usage or visual coding precision (assessed by orientation selectivity). Decreased serum leptin is known to be necessary for triggering energy-saving changes in V1 during food restriction. Consistent with this, we found significantly decreased serum leptin in food-restricted males but no significant change in food-restricted females. Collectively, our findings demonstrate that cortical function and energy usage in female mice are more resilient to food restriction than in males. The neocortex, therefore, contributes to sex-specific, energy-saving adaptations in response to food restriction.

Effects of intermittent fasting combined with exercise on serum leptin and adiponectin in adults with or without obesity: a systematic review and meta-analysis of randomized clinical trials

Context

Intermittent fasting (IF) and exercise training (Exe) have been evaluated in several studies for improving cardiometabolic biomarkers related to weight loss. However, further investigation is required to understand the potential effects on leptin and adiponectin concentrations. IF protocols have been shown to be efficient in improving adipokines, but further research is required to determine whether or not IF regimens combined with Exe are superior to Exe alone.

Objective

The aim of this study was to determine whether or not interventions combining IF plus Exe are more effective than Exe only for improving serum leptin and adiponectin in adults with and without obesity.

Data extraction

A systematic review and meta-analysis was performed by searching PubMed, Scopus, and Web of Science databases up to August 2023 for randomized clinical trials that determined the effects of IF plus Exe vs. Exe alone (control) on body weight, serum leptin, and serum adiponectin. Analyses were conducted for IF plus Exe vs. Exe alone to calculate weighted mean differences (WMD) and standardized mean differences (SMD).

Analysis

The current meta-analysis included 6 studies with a total sample of 153 participants, with intervention durations ranging from three days to 52 weeks. IF plus Exe elicited significantly larger decreases in leptin levels [SMD = -0.47, p = 0.03], which were accompanied by weight loss [WMD = -1.25 kg, p = 0.05], as compared with exercise-only interventions, but adiponectin did not differ between the two [SMD = 0.02, p = 0.9].

Conclusion

IF combined with Exe reduced leptin significantly, but did not change adiponectin levels, when compared to exercise only. Perhaps these reductions in leptin levels may have been associated with weight loss; however, due to the small number of included studies and the high heterogeneity in the weight loss outcomes, this result is uncertain.

Systematic review registration

https://www.crd.york.ac.uk/prospero/, identifier CRD42023460735.

The diagnostic agreement of sarcopenic obesity with different definitions in Chinese community-dwelling middle-aged and older adults

Background

In 2022, the European Society for Clinical Nutrition and Metabolism (ESPEN) and the European Association for the Study of Obesity (EASO) launched a consensus on the diagnostic methods for sarcopenic obesity (SO). The study aimed to identify the prevalence and diagnostic agreement of SO using different diagnostic methods in a cohort of subjects from West China aged at least 50 years old.

Methods

A large multi-ethnic sample of 4,155 participants from the West China Health and Aging Trend (WCHAT) study was analyzed. SO was defined according to the newly published consensus of the ESPEN/EASO. Furthermore, SO was diagnosed as a combination of sarcopenia and obesity. The criteria established by the Asian Working Group for Sarcopenia 2019 (AWGS2019) were used to define sarcopenia. Obesity was defined by four widely used indicators: percent of body fat (PBF), visceral fat area (VFA), waist circumference (WC), and body mass index (BMI). Cohen's kappa was used to analyze the diagnostic agreement of the above five diagnostic methods.

Results

A total of 4,155 participants were part of the study, including 1,499 men (63.76 ± 8.23 years) and 2,656 women (61.61 ± 8.20 years). The prevalence of SO was 0.63-7.22% with different diagnostic methods. The diagnosis agreement of five diagnostic methods was poor-to-good (κ: 0.06-0.67). The consensus by the ESPEN/EASO had the poorest agreement with other methods (κ: 0.06-0.32). AWGS+VFA had the best agreement with AWGS+WC (κ = 0.67), and consensus by the ESPEN/EASO had the best agreement with AWGS+ PBF (κ = 0.32).

Conclusion

The prevalence and diagnostic agreement of SO varies considerably between different diagnostic methods. AWGS+WC has the highest diagnostic rate in the diagnosis of SO, whereas AWGS+BMI has the lowest. AWGS+VFA has a relatively good diagnostic agreement with other diagnostic methods, while the consensus of the ESPEN/EASO has a poor diagnostic agreement. AWGS+PBF may be suitable for the alternative diagnosis of the 2022 ESPEN/EASO.

Association between insulin sensitivity and lean mass loss during weight loss

OBJECTIVE

The study objective was to assess the relationship between insulin sensitivity and changes in total lean mass (LM) and appendicular LM (ALM) during weight loss.

METHODS

Individuals were randomly assigned to either a standard or a moderately reduced carbohydrate diet for 16 weeks. Body composition was assessed using dual-energy x-ray absorptiometry and insulin sensitivity index (SI) using an intravenous glucose tolerance test. Multiple linear regression was used to determine whether baseline SI was predictive of changes in total LM and ALM.

RESULTS

Participants (n = 57; baseline BMI 32.1 ± 3.8 kg/m2) lost an average of 6.8 ± 3.2 kg of body weight (p < 0.001), with 1.5 ± 2.6 kg coming from LM (p < 0.05) and 0.5 ± 0.73 kg from ALM (p < 0.05). Multiple regression analysis demonstrated that SI was inversely associated with changes in total LM (kilograms; β = 0.481, p < 0.001), after adjusting for baseline LM, fat mass, acute insulin response to glucose, and weight loss. Similar results were seen when assessing ALM loss (β = 0.359, p < 0.05).

CONCLUSIONS

Identifying individuals with low insulin sensitivity prior to weight loss interventions may allow for a personalized approach aiming at minimizing LM loss.

Comparing the Efficacy of Digital and In-Person Weight Loss Interventions for Patients with Obesity and Glycemic Disorders: Evidence from a Randomized Non-Inferiority Trial

Digital weight loss interventions present a viable and cost-effective alternative to traditional therapy. However, further evidence is needed to establish the equal effectiveness of both approaches. This randomized controlled non-inferiority trial aimed to compare the effects of an intensive in-person weight loss intervention program with Vitadio digital therapy. One hundred patients with obesity and diagnosed with type 2 diabetes, prediabetes, or insulin resistance were enrolled and randomly assigned to one of the two treatment groups. Over a 6-month period, the control group received five in-person consultations with a physician who specialized in obesity treatment, a dietitian and/or a nutrition nurse, while the intervention group followed the digital program based on a multimodal therapeutic approach. The extent of weight loss was assessed and compared between the groups. Additionally, changes in body composition and metabolic parameters for the digital intervention group were analyzed. The study results demonstrated comparable effectiveness of both treatments for weight reduction. The positive effects of Vitadio were further evidenced by favorable changes in body composition and lipid metabolism and improved glycemic control in the intervention group. These findings suggest that Vitadio is an effective tool for assisting patients with managing obesity and preventing diabetes progression.

The effect of obesity pharmacotherapy on body composition, including muscle mass

Obesity pharmacotherapy represents a promising approach to treating obesity and may provide benefits beyond weight loss alone. Maintaining or even increasing muscle mass during weight loss is important to overall health, metabolic function and weight loss maintenance. Drugs such as liraglutide, semaglutide, tirzepatide, and naltrexone/bupropion have shown significant weight loss effects, and emerging evidence suggests they may also have effects on body composition, particularly a positive influence on muscle mass. However, further research is needed to fully understand the mechanism of action of these drugs and their effects on muscle mass. Clinicians should consider these factors when developing an obesity treatment plan for an individual patient.

Nutritional and Body Composition Changes in Paediatric β-Thalassemia Patients Undergoing Hematopoietic Stem Cell Transplantation: A Retrospective Study Using Bioelectrical Impedance Analysis

Objective

This retrospective study evaluated nutritional status and body composition changes in paediatric β-thalassemia (β-TM) patients before and after hematopoietic stem cell transplantation (HSCT), using bioelectrical impedance analysis (BIA), and explored their relationship with HSCT outcomes.

Methods

A cohort of 40 paediatric β-TM patients undergoing allogeneic HSCT was assessed for their nutritional status, anthropometric parameters, including body mass index (BMI), weight, and height, and body composition parameters pre-and post-HSCT, focusing on BIA measurements, including intracellular water (ICW), extracellular water (ECW), fat mass (FAT), fat-free mass (FFM), Skeletal Muscle Mass (SMM), soft Lean Mass (SLM), percent body fat (PBF), Body Cell Mass (BCM), Phase angle (PA) and muscle balance pre- and post-HSCT. Post-HSCT clinical outcomes, including acute graft-vs-host disease (aGVHD), engraftment time, oral mucositis (OM), sinusoidal obstruction syndrome (SOS), and diarrhoea in relation to nutrition status after HSCT were analysed.

Results

After HSCT, 28.21% experienced diminished nutritional status, with 71.43% of those who were wasting before HSCT showing diminished nutritional status, significantly higher than the normal group (18.75%, P = 0.012). Anthropometric changes included significant weight reduction (87.5%, 22.15 ± 7.46 vs 20.74 ± 6.57, P < 0.001) and BMI decrease (90%, 15.19 ± 1.70 vs 14.05 ± 1.48, P < 0.001). Body composition parameters, which are FFM, SMM, SLM, ICW, ECW, BCM, and PA (18.26 ± 5.71 vs 17.27 ± 5.19, 8.68 ± 3.30 vs 7.93 ± 3.02, 17.11 ± 5.28 vs 16.06 ± 4.84, 8.19 ± 2.54 vs 7.62 ± 2.31, 5.15 ± 1.58 vs 4.94 ± 1.47, 11.74 ± 3.63 vs 10.92 ± 3.32, 4.42 ± 0.50 vs 3.90 ± 0.57, respectively, P < 0.001) analysis revealed significant decreases. No significant differences in clinical outcomes were observed based on nutritional status.

Conclusion

Paediatric β-TM patients undergoing HSCT exhibit significant changes in nutrition status and body composition, emphasizing the need for focused attention on malnourished children who are more prone to diminished nutritional status. Comprehensive BIA aids in understanding the impact, urging consideration for extended follow-up and larger cohorts in future research.

Association of vitamins B1 and B2 intake with early-onset sarcopenia in the general adult population of the US: a cross-sectional study of NHANES data from 2011 to 2018

Background

Early-onset sarcopenia refers to the progressive loss of muscle mass and function that occurs at an early age. This condition perpetuates the vicious cycle of muscle loss and is associated with adverse outcomes. It is important to identify the contributing factors for early intervention and prevention. While diet is known to impact muscle mass, the association of B vitamins with early-onset sarcopenia remains unexplored.

Objectives

To investigate the association of B vitamins intake with early-onset sarcopenia risk in a cross-sectional study.

Methods

We conducted data analysis on a total of 8,711 participants aged between 20 and 59 years who took part in the National Health and Nutrition Examination Survey (NHANES) from 2011 to 2018. Early-onset sarcopenia was defined as a SMI measured by DXA that was one standard deviation below the sex-specific mean of the reference population. B vitamins intake (B1, B2, B3, B6, B9, and B12) was assessed by 24-h dietary recall. We used weighted multiple logistic regression and RCS models to estimate the OR and 95% CI of sarcopenia by B vitamins intake, adjusting for demographic, physical, lifestyle, comorbidities, and nutritional covariates.

Results

Higher intake of vitamin B1 was associated with a 22% lower sarcopenia risk (OR = 0.78, CI = 0.63-0.97, p = 0.022), and higher intake of vitamin B2 with a 16% lower risk (OR = 0.84, CI = 0.74-0.97, p = 0.012) in both genders. Gender-specific analyses showed a 28% reduction in sarcopenia risk among males with each additional mg of vitamin B1 intake (OR = 0.72, CI = 0.52-0.97, p = 0.038), and a 26% decrease among females with each additional mg of vitamin B2 intake (OR = 0.74, CI = 0.57-0.96, p = 0.021). No significant differences were found between vitamin B2 and males, or between vitamin B1 and females. The RCS model suggested a nonlinear relationship between vitamin B2 intake and sarcopenia risk (POverall = 0.001, PNonlinear = 0.033), with a plateau effect above 3 mg/d.

Conclusion

Higher intake of vitamin B1 and B2 may lower the risk of early-onset sarcopenia, with gender differences. This suggests the potential of nutritional intervention by increasing these vitamins intake through diet and supplements. Further research is warranted to elucidate the mechanisms and design targeted interventions.

Game changers: do new medications make lifestyle-based treatment of obesity obsolete?

Historically, obesity was viewed as a lifestyle disease, with an associated lifestyle solution, and approaches that embody the "eat less, move more" idea have dominated obesity treatment recommendations for over half a century. Meanwhile, the prevalence and severity of obesity continue to increase globally. Enter the so-called "game changers": glucagon-like peptide-1 receptor agonists. In the media frenzy around these and other new antiobesity medications in the pipeline, lifestyle-based treatment researchers and practitioners may find themselves wondering whether behavioral approaches to obesity will become obsolete in this new therapeutic era. In this Perspective, the authors contend that medical approaches impact physiologic pathways to support the success of behavioral approaches. Similarly, behavioral approaches can improve weight loss-adjacent outcomes that are not addressed by medication. Thus, the two approaches are complementary and must coexist if we are to make a significant, population-level impact on the obesity epidemic.

Effects of 12 Weeks of Resistance Training on Body Composition, Muscle Hypertrophy and Function, Blood Lipid Level, and Hemorheological Properties in Middle-Aged Obese Women

Background

This study investigated the effects of 12-week resistance training on body composition, blood pressure, blood lipid levels, muscle cross-sectional area (CSA), isokinetic muscle function, and hemorheological properties in middle-aged obese women.

Methods

Twenty-eight obese women with a mean age of 50.79 ± 5.80 years were randomly assigned to the control (CON, n = 13) or experimental (EXP, n = 15) group. The EXP group underwent a resistance training program composed of warm-up, main resistance exercise (deadlift, barbell squat, seated leg extension, and lying leg curl, bench press, preacher bench biceps curl, barbell rowing, and dumbbell shoulder press), and cool-down. The resistance exercise consisted of three sets of 8-10 repetitions (reps) performed with 70-80% of 1-rep maximum, and reps and sets were increased every 3 weeks. The training frequency was 80 min, 3 days per week for 12 weeks. The CON group maintained their daily lifestyle without training. All participants underwent measurements of body composition (weight, body mass index, lean body mass, fat mass, and % body fat), blood pressure (systolic blood pressure, diastolic blood pressure, mean arterial pressure, and pulse pressure), blood lipid levels (triglycerides, total cholesterol, high-density lipoprotein cholesterol, and low-density lipoprotein cholesterol), CSA of the muscles (quadriceps, hamstring, and total thigh muscle), isokinetic muscle function (peak torque [PT], relative PT, mean power, and total work [TW]), and hemorheological properties (erythrocyte deformability and aggregation) before and after 12 weeks of training.

Results

The EXP group showed a significant improved muscle function, including PT (p < 0.001), relative PT (p < 0.001) in extension 60°/s, TW (p < 0.001) in extension 180°/s, and TW (p = 0.018) in flexion 180°/s. Regarding hemorheological properties, the EXP group showed significant improvement in erythrocyte aggregation (p < 0.001) and deformability (p < 0.001).

Conclusions

The present study verified that our resistance training program resulted in greater muscle function, decreased fat mass, and improved hemorheological properties.

Clinical Trial Registration

This study was registered with cris.nih.go.kr (No. KCT0007412).

Obesity Weight Loss Phenotypes in CKD: Findings From the Chronic Renal Insufficiency Cohort Study

Introduction

Although people with chronic kidney disease (CKD) and obesity have important motivations to lose weight, weight loss is also associated with health risks. We examined whether patterns of change in systolic blood pressure (SBP), serum albumin level, and fat-free mass (FFM) can help to differentiate between healthy and high-risk weight loss in this population.

Methods

Using data from the Chronic Renal Insufficiency Cohort Study (CRIC), we estimated a joint multivariate latent class model with 6 classes to identify distinct trajectories of body mass index (BMI), albumin, and SBP among participants with obesity (BMI ≥30 kg/m2 at baseline), accounting for informative missingness from death. In a secondary analysis, we fit a 6-class model with BMI and FFM.

Results

Among 2831 participants (median baseline BMI 35.6, interquartile range [IQR] 32.4-40.0 kg/m2), median follow-up was 6.8 (IQR 4.8-12.9) years, median age was 61 (IQR 54-67) years, 53% were male, 50% were non-Hispanic Black, and 82% were trying to control or lose weight at baseline. Latent classes were associated with mortality risk (5-year cumulative incidence of mortality 6.8% and 1.5% in class 6 and 3, respectively). Class 6 had the highest mortality rate and was characterized by early, steep BMI loss, early serum albumin decline, and late SBP increase. In the secondary analysis, a class characterized by steep BMI and FFM loss was associated with the highest death risk.

Conclusions

Among adults with CKD and obesity, BMI loss with concomitant serum albumin or FFM loss was associated with a high risk of death.

Skeletal Muscle Endogenous Estrogen Production Ameliorates the Metabolic Consequences of a High-Fat Diet in Male Mice

AIMS

The role of skeletal muscle estrogen and its ability to mitigate the negative impact of a high-fat diet (HFD) on obesity-associated metabolic impairments is unknown. To address this, we developed a novel mouse model to determine the role of endogenous 17β-estradiol (E2) production in males in skeletal muscle via inducible, skeletal muscle-specific aromatase overexpression (SkM-Arom↑).

METHODS

Male SkM-Arom↑ mice and littermate controls were fed a HFD for 14 weeks prior to induction of SkM-Arom↑ for a period of 6.5 weeks. Glucose tolerance, insulin action, adipose tissue inflammation, and body composition were assessed. Indirect calorimetry and behavioral phenotyping experiments were performed using metabolic cages. Liquid chromatography mass spectrometry was used to determine circulating and tissue (skeletal muscle, hepatic, and adipose) E2 and testosterone concentrations.

RESULTS

SkM-Arom↑ significantly increased E2 in skeletal muscle, circulation, the liver, and adipose tissue. SkM-Arom↑ ameliorated HFD-induced hyperglycemia, hyperinsulinemia, impaired glucose tolerance, adipose tissue inflammation, and reduced hepatic lipid accumulation while eliciting skeletal muscle hypertrophy.

CONCLUSION

Enhanced skeletal muscle aromatase activity in male mice induces weight loss, improves metabolic and inflammatory outcomes and mitigates the negative effects of a HFD. Additionally, our data demonstrate for the first time skeletal muscle E2 has anabolic effects on the musculoskeletal system.

Comparison of Protein- or Amino Acid-Based Supplements in the Rehabilitation of Men with Severe Obesity: A Randomized Controlled Pilot Study

BACKGROUND

Weight loss is associated with a reduction in all body compartments, including muscle mass (MM), and this effect produces a decrease in function and muscle strength. Our objective was to assess the impact of protein or amino acid supplements on MM loss in middle-aged men (age < 65 years) with severe obesity (BMI > 35 kg/m2) during weight loss.

MATERIALS AND METHODS

We conducted a single-site randomized controlled trial (Clinicaltrials.gov NCT05143398) with 40 in-patient male subjects with severe obesity. Participants underwent an intervention program consisting of a low-calorie balanced diet and structured physical activity. They were randomly assigned to 4-week treatment groups: (1) control (CTR, N = 10), (2) protein (P, N = 10), (3) branched-chain amino acid (BCAA, N = 10), and (4) essential amino acid mixture with tricarboxylic acid cycle intermediates (PD-E07, N = 10) supplementation.

RESULTS

Following 4 weeks of intervention, all groups showed similar reductions in body weight compared to baseline. When examining the delta values, a notable increase in muscle mass (MM) was observed in the PD-E07 intervention group [MM (kg): 2.84 ± 3.57; MM (%): 3.63 ± 3.14], in contrast to the CTR group [MM (kg): -2.46 ± 3.04; MM (%): -0.47 ± 2.28], with a statistical significance of p = 0.045 and p = 0.023, respectively. However, the MM values for the P group [MM (kg): -2.75 ± 5.98, p = 0.734; MM (%): -0.44 ± 4.02, p = 0.990] and the BCAA group [MM (kg): -1 ± 3.3, p = 0.734; MM (%): 0.34 ± 2.85, p = 0.956] did not exhibit a statistically significant difference when compared to the CTR group.

CONCLUSIONS

Amino acid-based supplements may effectively mitigate the loss of MM typically observed during weight reduction. Further validation through large-scale studies is necessary.

High-intensity interval training prevents muscle mass loss in overweight Chilean young adults during a hypocaloric-Mediterranean diet: a randomized trial

The hypocaloric Mediterranean diet (MD) mainly reduces fat mass but inevitably causes a loss of skeletal muscle mass. High-intensity interval training (HIIT) seems to have advantages in preserving muscle mass during a hypocaloric regime. Our study compares body composition and metabolic changes in overweight and obese Chilean women and men after 3 months of weight loss treatment with a Mediterranean-type hypocaloric diet, HIIT, or a combination of both. The study included 83 overweight or obese women and men between the ages of 25 and 50. The subjects were randomly assigned to one of the three intervention groups: (1) MD, (2) EX, and (3) MD + EX. Baseline and post-intervention measurements included: (a) body composition by dual-beam densitometry, muscle, and fat measurements by thigh ultrasound and computed tomography; (b) handgrip and quadriceps muscle strength; (c) exercise performance by peak oxygen consumption, peak load, work efficiency, and exercise energy expenditure; and (d) metabolic parameters. Out of 83 participants, the retention rate was 49% due to low compliance with the interventions. As expected, the MD group resulted in significantly greater weight loss (MD -7%, EX -0.6% and MD + EX -5.3%) and appendicular fat mass loss (MD -11.1%, EX -2.9, MD + EX -10.2%) but was associated with significant lean tissue loss (2.8%), which was prevented by HIIT (EX -0.1 and MD + EX -0.6%). Metabolic and glycoxidative parameters remained unchanged, irrespective of changes in body composition. Hypocaloric diets remain the most effective means to lose weight and body fat. However, it induces a loss of lean body mass when not accompanied by exercise training. This study shows that HIIT prevents the loss of muscle mass caused by a hypocaloric Mediterranean diet.

Nutrition and exercise interventions to improve body composition for persons with overweight or obesity near retirement age: A systematic review and network meta-analysis of randomised controlled trials

The retirement phase is an opportunity to integrate healthy (nutrition/exercise) habits into daily life. We conducted this systematic review to assess which nutrition and exercise interventions most effectively improve body composition (fat/muscle mass), body mass index (BMI) and waist circumference (WC) in persons with obesity/overweight near retirement age (ages 55-70). We conducted a systematic review and network-meta-analysis (NMA) of randomised controlled trials, searching four databases from their inception up to 12 July 2022. The NMA was based on a random effects model, pooled mean differences, standardised mean differences, their 95% confidence intervals, and correlations with multi-arm studies. Subgroup and sensitivity analyses were also conducted. 92 studies were included, 66 of which with 4957 participants could be used for the NMA. Identified interventions were clustered into 12 groups: no intervention, energy restriction (i.e. 500-1000 kcal), energy restriction plus high protein (HP) intake (1.1-1.7 g/kg/body weight), intermittent fasting, mixed exercise (aerobic and resistance), resistance training (RT), aerobic training (AT), HP plus RT, energy restriction plus HP plus exercise, energy restriction plus RT, energy restriction plus AT, and energy restriction plus mixed exercise (ME). Intervention durations ranged from 8 weeks to 6 months. Body fat was reduced with energy restriction plus any exercise or plus HP intake. Energy restriction alone was less effective and tended to decrease muscle mass. Muscle mass was only significantly increased with ME. All other interventions including exercise effectively preserved muscle mass. A BMI and/or WC decrease was achieved with all interventions except AT/RT alone or RT plus HP. Overall, the most effective strategy for nearly all outcomes was combining energy restriction with RT or ME and HP. Healthcare professionals involved in the management of persons with obesity need to be aware that an energy-restricted diet alone may contribute to sarcopenic obesity in persons near retirement age. This network meta-analysis is registered at https://www.crd.york.ac.uk/prospero/as CRD42021276465.

Recommendations for the prevention and management of obesity in the Iraqi population

Obesity is a chronic metabolic disease that has become one of the leading causes of disability and death in the world, affecting not only adults but also children and adolescents. In Iraq, one third of the adult population is overweight and another third obese. Clinical diagnosis is accomplished by measuring body mass index (BMI) and waist circumference (a marker for intra-visceral fat and higher metabolic and cardiovascular disease risk). A complex interaction between behavioral, social (rapid urbanization), environmental and genetic factors underlies the etiology of the disease. Treatment options for obesity may include a multicomponent approach, involving dietary changes to reduce calorie intake, an increase in physical activity, behavioral modification, pharmacotherapy and bariatric surgery. The purpose for these recommendations is to develop a management plan and standards of care that are relevant to the Iraqi population and that can prevent/manage obesity and obesity-related complications, for the promotion of a healthy community.

Usual dietary intake, physical activity, weight loss, and body composition after five years of Roux-en-Y gastric bypass

OBJECTIVE

To estimate usual dietary intake (UDI), physical activity (PA), and their association with weight loss and body composition in patients who underwent Roux-en-Y gastric bypass (RYGB) after five years in the Federal District, Brazil.

METHODS

We assessed anthropometry and body composition using bioimpedance, and dietary intake and PA with three nonconsecutive 24-h recalls. PC-Side was used to estimate UDI. Dietary patterns (DPs) were identified through principal component analysis, and association between UDI and PA with percentage of total weight loss (%TWL) and fat-free mass (FFM) through multinomial logistic regression.

RESULTS

Sample (n = 124) presented mean (SD) age of 48.9 (9.4) years, median (IQR) of 9 years (7-10) post RYGB, current BMI = 32.3 kg/m² (28.8-35.7), %TWL = 24.7% (10.9), and FFM = 45.1 kg (41.1-51.9). Mean usual energy intake of 1556 kcal/d, with adequate protein intake, poor fiber intake, and excessive carbohydrate, total fat, and added sugar intake, compared to dietary guidelines. Calcium, vitamins C, D, and E presented the greatest inadequacy (15%, 24%, 32%, and 49% of individuals, respectively, reported usual intake below EAR); 83 participants were considered active/very active, according PA. DP with high energy, protein, total fat, saturated fat, and sodium intake, was negatively associated with %TWL (OR = 0.545, p = 0.037). Protein intake was positively associated with FFM (OR = 1.091, p = 0.004). PA was not associated with %TWL or FFM.

CONCLUSION

Participants demonstrated intake of carbohydrate, fat, fiber, added sugar not in accordance with guidelines. A DP rich in energy, protein, total fat, saturated fat, and sodium appears to decrease TWL. However, protein intake appears to increase FFM.

After the spotlight: are evidence-based recommendations for refeeding post-contest energy restriction available for physique athletes? A scoping review

Background: To date, there is limited consensus on post-contest recovery recommendations for natural physique athletes. The available literature emphasizes the negative consequences of extreme dieting associated with physique contests, yet offers only speculative suggestions to facilitate physiological recovery post-contest. This scoping review evaluates evidence-based recommendations for recovery in post-physique contests. Methods: The online search engines and databases Google Scholar, PubMed, and Scopus were searched systematically and 12 peer reviewed journal articles were included in the review. Results: Six key factors were identified that directly impacted on physiological recovery post-contest: (1) body composition, (2) recovery dietary intake, (3) resting metabolic rate (RMR) restoration, (4) endocrine measures recovery, (5) menstrual cycle recovery, and (6) psychological aspects of recovery. Conclusions: Three dietary strategies have been proposed to facilitate physiological recovery post-contest while bearing in mind body composition and future athlete outcomes; (1) a gradual increase in energy intake to maintenance requirements, (2) ad libitum eating, (3) an immediate return to maintenance energy requirements. Future research is required to determine the timeline in which full physiological recovery occurs post-contest and which strategies best support athlete health and performance during post-contest recovery.

Apol9a regulates myogenic differentiation via the ERK1/2 pathway in C2C12 cells

Background: The rising prevalence of obesity and its complications is a big challenge for the global public health. Obesity is accompanied by biological dysfunction of skeletal muscle and the development of muscle atrophy. The deep knowledge of key molecular mechanisms underlying myogenic differentiation is crucial for discovering novel targets for the treatment of obesity and obesity-related muscle atrophy. However, no effective target is currently known for obesity-induced skeletal muscle atrophy. Methods: Transcriptomic analyses were performed to identify genes associated with the regulation of myogenic differentiation and their potential mechanisms of action. C2C12 cells were used to assess the myogenic effect of Apol9a through immunocytochemistry, western blotting, quantitative polymerase chain reaction, RNA interference or overexpression, and lipidomics. Results: RNA-seq of differentiated and undifferentiated C2C12 cells revealed that Apol9a expression significantly increased following myogenic differentiation and decreased during obesity-induced muscle atrophy. Apol9a silencing in these C2C12 cells suppressed the expression of myogenesis-related genes and reduced the accumulation of intracellular triglycerides. Furthermore, RNA-seq and western blot results suggest that Apol9a regulates myogenic differentiation through the activation of extracellular signal-regulated kinase 1/2 (ERK1/2). This assumption was subsequently confirmed by intervention with PD98059. Conclusion: In this study, we found that Apol9a regulates myogenic differentiation via the ERK1/2 pathway. These results broaden the putative function of Apol9a during myogenic differentiation and provide a promising therapeutic target for intervention in obesity and obesity-induced muscle atrophy.

Thirty Obesity Myths, Misunderstandings, and/or Oversimplifications: An Obesity Medicine Association (OMA) Clinical Practice Statement (CPS) 2022

Background

This Obesity Medicine Association (OMA) Clinical Practice Statement (CPS) is intended to provide clinicians an overview of 30 common obesity myths, misunderstandings, and/or oversimplifications.

Methods

The scientific support for this CPS is based upon published citations, clinical perspectives of OMA authors, and peer review by the Obesity Medicine Association leadership.

Results

This CPS discusses 30 common obesity myths, misunderstandings, and/or oversimplifications, utilizing referenced scientific publications such as the integrative use of other published OMA CPSs to help explain the applicable physiology/pathophysiology.

Conclusions

This Obesity Medicine Association (OMA) Clinical Practice Statement (CPS) on 30 common obesity myths, misunderstandings, and/or oversimplifications is one of a series of OMA CPSs designed to assist clinicians in the care of patients with the disease of obesity. Knowledge of the underlying science may assist the obesity medicine clinician improve the care of patients with obesity.

Obesity-Related Chronic Kidney Disease: Principal Mechanisms and New Approaches in Nutritional Management

Obesity is the epidemic of our era and its incidence is supposed to increase by more than 30% by 2030. It is commonly defined as a chronic and metabolic disease with an excessive accumulation of body fat in relation to fat-free mass, both in terms of quantity and distribution at specific points on the body. The effects of obesity have an important impact on different clinical areas, particularly endocrinology, cardiology, and nephrology. Indeed, increased rates of obesity have been associated with increased risk of cardiovascular disease (CVD), cancer, type 2 diabetes (T2D), dyslipidemia, hypertension, renal diseases, and neurocognitive impairment. Obesity-related chronic kidney disease (CKD) has been ascribed to intrarenal fat accumulation along the proximal tubule, glomeruli, renal sinus, and around the kidney capsule, and to hemodynamic changes with hyperfiltration, albuminuria, and impaired glomerular filtration rate. In addition, hypertension, dyslipidemia, and diabetes, which arise as a consequence of overweight, contribute to amplifying renal dysfunction in both the native and transplanted kidney. Overall, several mechanisms are closely related to the onset and progression of CKD in the general population, including changes in renal hemodynamics, neurohumoral pathways, renal adiposity, local and systemic inflammation, dysbiosis of microbiota, insulin resistance, and fibrotic process. Unfortunately, there are no clinical practice guidelines for the management of patients with obesity-related CKD. Therefore, dietary management is based on the clinical practice guidelines for the nutritional care of adults with CKD, developed and published by the National Kidney Foundation, Kidney Disease Outcome Quality Initiative and common recommendations for the healthy population. Optimal nutritional management of these patients should follow the guidelines of the Mediterranean diet, which is known to be associated with a lower incidence of CVD and beneficial effects on chronic diseases such as diabetes, obesity, and cognitive health. Mediterranean-style diets are often unsuccessful in promoting efficient weight loss, especially in patients with altered glucose metabolism. For this purpose, this review also discusses the use of non-classical weight loss approaches in CKD, including intermittent fasting and ketogenic diet to contrast the onset and progression of obesity-related CKD.

Impact of Intermittent Fasting Combined With High-Intensity Interval Training on Body Composition, Metabolic Biomarkers, and Physical Fitness in Women With Obesity

Background

Intermittent fasting (IF) is a dietary approach that is widely popular due to its effects on weight and body fat loss, but it does not appear to ensure muscle mass preservation. Incorporating high-intensity interval training (HIIT) into an individual’s routine could be an attractive and viable therapeutic option for improving body composition, lifestyle and health promotion. Problematizing the emerging situation of fighting obesity, led us to clarify gaps about IF and hypothesize that IF and HIIT in conjunction may protect against muscle mass decline without impairing nitrogen balance (NB), in addition to improving the physical fitness of women with obesity.

Objectives

To evaluate the effects of IF alone and combined with HIIT on body composition, NB and strength and physical fitness in women with obesity.

Methods

Thirty-six women (BMI 34.0 ± 3.2; 32.2 ± 4.4 years) participated and were randomly distributed into three groups: (1) Intermittent fasting combined with exercise group (IF + EX); (2) Exercise group (EX); and (3) Intermittent fasting group (IF). The interventions took place over 8 weeks and all evaluations were performed pre and post-intervention. The HIIT circuit was performed 3x/week, for 25 mins/session, at 70–85% of the maximum heart rate. The intermittent fasting protocol was a 5:2 diet with two meals within 6 h on fasting days, being 25% of total energy intake, plus 18 h of complete fasting. The protocol was performed 2x/week and 5 days of ad libitum ingestion. Resting metabolic rate (RMR) was measured by indirect calorimetry, body composition by BodPod®, NB from urinary nitrogen, food consumption by food records and physical and strength performance were measured by physical tests. ANOVA two-way repeated measures mixed model was performed followed by Sidak post hoc (p &lt; 0.05). This project was registered in ClinicalTrials.gov, NCT05237154.

Results

There were a reduction in body weight (P = 0.012) and BMI (P = 0.031) only in the IF + EX group. There was body fat loss in the IF + EX group (−4%, P &lt; 0.001) and in the EX group (−2.3%, P = 0.043), an increase in fat-free mass in the IF + EX group (+3.3%, P &lt; 0.001) and also in the EX group (+2%, P = 0.043), without differences between groups and the IF group showed no changes. The NB was equilibrium in all groups. All parameters of aerobic capacity and strength improved.

Conclusion

Combining IF with HIIT can promote increments in fat-free mass, NB equilibrium and improve physical fitness and strength.

Home-Based HIIT and Traditional MICT Prescriptions Improve Cardiorespiratory Fitness to a Similar Extent Within an Exercise Referral Scheme for At-Risk Individuals

Exercise referral schemes (ERS) are used to promote physical activity within primary care. Traditionally, ERS are conducted in a gym or leisure-center setting, with exercise prescriptions based on moderate-intensity continuous training (MICT). Home-based high-intensity interval training (Home-HIIT) has the potential to reduce perceived barriers to exercise, including lack of time and access to facilities, compared to traditional MICT prescription used with ERS and improve health related outcomes. We hypothesized that Home-HIIT would mediate greater improvement in cardiorespiratory fitness (CRF) by virtue of greater adherence and compliance to the exercise prescription, compared to MICT. Methods: Patients enrolled on an ERS (Liverpool, United Kingdom) were recruited for a pragmatic trial. Participants self-selected either 12 weeks of MICT (45-135 min/week at 50-70% HR_max) or Home-HIIT (4-9 min × 1 min intervals at ≥80% of HR_max, interspersed with 1 min rest). The primary outcome was the change in CRF (VO_{2 peak}) at post-intervention (12 weeks) and follow-up (3-month post intervention), using intention-to-treat analysis. Results: 154 participants (age 48 ± 10y; BMI 30.5 ± 6.1 kg/m²) were recruited between October 2017 and March 2019, 87 (56%) participants chose Home-HIIT and 67 (44%) MICT. VO_{2 peak} increased post-intervention in both groups (MICT 3.9 ± 6.0 ml.kg^-1.min^-1, Home-HIIT 2.8 ± 4.5 ml.kg^-1.min^-1, P < 0.001), and was maintained at follow-up (P < 0.001). Fat mass was only reduced post MICT (MICT -1.5 ± 6.3 kg, P < 0.05, Home-HIIT -0.2 ± 2.0 kg, P = 1.00), but the reduction was not maintained at follow-up (MICT -0.6 ± 5.1 kg, Home-HIIT 0.0 ± 2.2 kg, P > 0.05). Adherence to the prescribed programs was similar (MICT 48 ± 35%, Home-HIIT 39 ± 36%, P = 0.77). Conclusion: This is the first study to evaluate the use of Home-HIIT for individuals in a primary care setting. Contrary to our hypothesis, adherence to both exercise prescriptions was poor, and CRF improved to a similar extent in both groups with improvements maintained at 3-month follow-up. We provide evidence that, although not superior, Home-HIIT could be an effective and popular additional exercise choice for patients within primary care based ERS. Clinical Trial Registration: [ClinicalTrials.gov], identifier [NCT04553614].