Effects of metformin on glucose metabolism and mitochondrial function in patients with obstructive sleep apnea: A pilot randomized trial.

Obstructive sleep apnea (OSA) is associated with increased risk for diabetes, and standard treatment with positive airway pressure (PAP) device shows inconsistent effects on glucose metabolism. Metformin is known to treat and prevent diabetes, but its effects on skeletal muscle mitochondrial function are not completely understood. Here, we evaluate the effects of metformin on glucose metabolism and skeletal muscle mitochondrial function in patients with OSA. Sixteen adults with obesity (50.9 ± 6.7 years, BMI: 36.5 ± 2.9 kg/m2 ) and moderate-to-severe OSA were provided with PAP treatment and randomized to 3 months of placebo (n = 8) or metformin (n = 8) treatment in a double-blind parallel-group design. Whole body glucose metabolism was determined by oral glucose tolerance test. A skeletal muscle biopsy was obtained to evaluate mitochondrial respiratory capacity and expression of proteins related to mitochondrial dynamics and energy metabolism. Whole body insulin-sensitivity (Matsuda index) did not change in metformin or placebo treated groups. However, metformin treatment prevented increases in insulin release relative to placebo during follow-up. Insulin area under the curve (AUC) and insulin to glucose AUC ratio increased in placebo but remained unchanged with metformin. Furthermore, metformin treatment improved skeletal muscle mitochondrial respiratory capacity and dynamics relative to placebo. Metformin treatment prevented the decline in whole body glucose homeostasis and skeletal muscle mitochondrial function in patients with moderate to severe OSA. Patients with OSA may benefit from the addition of metformin to prevent diabetes.

Validation of remote child weight and height measurements within a weight management trial.

OBJECTIVE: The aim of this substudy within the Treatment Efforts Addressing Child Weight Management by Unifying Patients, Parents, and Providers (TEAM UP) pragmatic clinical trial was to compare the validity of anthropometric measurements collected remotely versus in person (≤7 days apart) among youth with obesity who were 6 to 15 years of age. METHODS: Child (n = 37) weight and height were measured in person by a trained data assessor. These were compared with measurements taken remotely by the child's parent with live videoconferencing observation by a study data assessor. In-person and remote measurements were compared using Bland-Altman plots, Pearson correlations, and two one-sided paired t tests. A priori bounds of acceptability were set at ±0.68 kg to allow for typical weight fluctuations within the 7-day comparison period. RESULTS: Measurements were highly correlated (height: r = 0.991, p < 0.0001; weight: r = 0.999; p = 0.03). For height, two one-sided t tests for upper, t(36) = 3.95, and lower, t(36) = -2.63, bounds (-1, 1) revealed an overall p = 0.006; absolute error was 3.5 cm. For weight, two one-sided t tests for upper, t(36) = 1.93, and lower, t(36) = -7.91, bounds (-0.68, 0.68) revealed an overall p = 0.03; absolute error was 1.7 kg. CONCLUSIONS: The present findings support the utility and interpretation of remotely assessed weight management outcomes for both research and clinical purposes. These procedures may offer greater accessibility to evidence-based measurement.

Effects of Episodic Food Insecurity on Psychological and Physiological Responses in African American Women With Obesity (RESPONSES): Protocol for a Longitudinal Observational Cohort Study.

BACKGROUND: Food insecurity is a risk factor for multiple chronic diseases, including obesity. Importantly, both food insecurity and obesity are more prevalent in African American women than in other groups. Furthermore, food insecurity is considered a cyclic phenomenon, with episodes of food adequacy (ie, enough food to eat) and food shortage (ie, not enough food to eat). More research is needed to better understand why food insecurity is linked to obesity, including acknowledging the episodic nature of food insecurity as a stressor and identifying underlying mechanisms. OBJECTIVE: The objective of this study is to investigate the episodic nature of food insecurity as a stressor via responses in body weight and psychological and physiological parameters longitudinally and do so in a health-disparate population-African American women. METHODS: We enrolled 60 African American women (food-insecure cohort: n=30, 50%; food-secure cohort: n=30, 50%) aged 18-65 years with obesity (BMI 30-50 kg/m2) to measure (1) daily body weight remotely over 22 weeks and (2) psychological and physiological parameters via clinic assessments at the beginning and end of the 22-week study. Furthermore, we are assessing episodes of food insecurity, stress, hedonic eating, and appetite on a weekly basis. We hypothesize that food-insecure African American women with obesity will demonstrate increased body weight and changes in psychological and physiological end points, whereas food-secure African American women with obesity will not. We are also examining associations between changes in psychological and physiological parameters and changes in body weight and performing a mediation analysis on the psychological parameters assessed at the study midpoint. Psychological questionnaires are used to assess stress; executive function, decision-making, and motivation; and affect and nonhomeostatic eating. Physiological measurements are used to evaluate the levels of cortisol, dehydroepiandrosterone-sulfate (DHEA-S), C-reactive protein, thyroid hormones, blood glucose, glycated hemoglobin, and insulin, as well as allostatic load. RESULTS: This study has completed participant recruitment (n=60). At the time of study enrollment, the mean age of the participants was almost 47 (SD 10.8) years, and they had a mean BMI of 39.6 (SD 5.31) kg/m2. All data are anticipated to be collected by the end of 2023. CONCLUSIONS: We believe that this is the first study to examine changes in body weight and psychological and physiological factors in food-insecure African American women with obesity. This study has significant public health implications because it addresses the cyclic nature of food insecurity to identify underlying mechanisms that can be targeted to mitigate the adverse relationship between food insecurity and obesity and reduce health disparities in minority populations. TRIAL REGISTRATION: ClinicalTrials.gov NCT05076487; https://clinicaltrials.gov/study/NCT05076487. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): DERR1-10.2196/52193.

Validity of an Artificial Intelligence-Based Application to Identify Foods and Estimate Energy Intake Among Adults: A Pilot Study.

Background: The commercial application Openfit allows for automatic identification and quantification of food intake through short video capture without a physical reference marker. There are no known peer-reviewed publications on the validity of this Nutrition Artificial Intelligence (AI). Objectives: To test the validity of Openfit to identify food automatically and semiautomatically (with user correction), test the validity of Openfit at quantifying energy intake (kcal) automatically and semiautomatically, and assess satisfaction and usability of Openfit. Methods: During a laboratory-based visit, adults (7 male and 17 female), used Openfit to automatically and semiautomatically record provided meals, which were covertly weighed. Foods logged were identified as an "exact match," "far match," or an "intrusion" using Food and Nutrient Database for Dietary Studies (FNDDS) codes. Descriptive data were stratified by meal, food item, and FNDDS group, and presented with or without beverages. Bland-Altman analyses assessed errors over levels of energy intake. Participants completed a User Satisfaction Survey (USS) and the Computer Systems Usability Questionnaire (CSUQ). Open-ended questions were assessed with qualitative methods. Results: Exact matches, far matches, and intrusions were 46%, 41%, and 13% for automated identification, and 87%, 23%, and 0% for semiautomated identification, respectively. Error for automated and semiautomated energy estimates were 43% and 33% with beverages, and 16% and 42% without beverages. Bland-Altman analyses indicated larger error for higher energy meals. Overall mean scores were 2.4 for the CSUQ and subscale means scores ranged from 4.1 to 5.5. for the USS. Participants recommended improvements to Openfit's Nutrition AI, manual estimation, and overall app. Conclusion: Openfit worked relatively well for automatically and semiautomatically identifying foods. Error in automated energy estimates was relatively high; however, after excluding beverages, error was relatively low (16%). For semiautomated energy estimates, error was comparable to previous studies. Improvements to the Nutrition AI, manual estimation and overall application may increase Openfit's usability and validity.This trial was registered at clinicaltrials.gov as NCT05343585.

Access, Interest, and Barriers to Incorporation of Birth Doula Care in the United States.

Doula care improves maternal care, yet barriers exist to incorporating doula care. The purpose of this study was to evaluate interest and barriers to doula care. Overall, 508 women, 26-35 years of age (54.5%), White/Caucasian (89.8%), and married (88.6%), completed this study. Most reported ≥1 previous birth (97.6%). Respondents would "feel comfortable" (73.2%) and "more confident" (54.9%) with doula care at birth, and 57.9% reported their provider would be supportive of doula care. Only 39.0% expressed benefits to doula care during pregnancy compared to 72.6% at birth and 68.1% during postpartum. Most would hire a doula if health insurance covered some of the costs. Despite the recognized benefits and support of doula care, cost-associated barriers exist to the incorporation of doula care.

Temporal Changes in Energy-Balance Behaviors and Home Factors in Adolescents with Normal Weight and Those with Overweight or Obesity.

This study aimed to examine the temporal changes in energy-balance behaviors and home factors in adolescents with normal weight and those with overweight or obesity (OWOB). Adolescents or parent proxies completed survey assessments two to four years before (T0; n=82), ≤ six months before (T1; n=68), and ≤ three months after the COVID-19 pandemic outbreak (T2; n=82), to capture energy-balance behaviors (i.e., physical activity [PA], screen time, sleep) and home factors (i.e., food environment, food worry, parent support for PA). At T0 and T1 (before pandemic), participants visited our laboratory for anthropometric measurements. At T2, parent proxies also completed a survey to report the COVID-19 pandemic exposure and impact. The participating families experienced moderate levels of pandemic exposure and impact, although exposure was higher in the OWOB group F1,78=5.50,p<.05. Repeated-measure multivariate analyses of covariance (RM-MACOVAs) did not show significant time by weight status interaction effects (p>0.05; adjusted for race and sex). However, the models detected significant time (T0 vs. T2) by race (White vs. non-White) interaction effect λ7,66=0.81,p<0.05, with greater increase in food worry F1,72=4.36,p<.05 but less increase in screen time F1,72=4.54,p<.05 among the non-White group. Graphical visualization depicted some favorable change patterns in adolescents with normal weight (vs. those with OWOB) for certain behaviors and home factors (e.g., number of days per week ≥ 60 mins PA, food worry). These findings suggest that the COVID-19 pandemic exerted greater adverse effects on adolescents with OWOB and specifically on screen time and food worry among non-White adolescents.

Painted playgrounds for preschoolers' physical activity and fundamental motor skill improvement: a randomized controlled pilot trial of effectiveness.

BACKGROUND: Preschool children are not meeting recommended levels of physical activity (PA) nor are they proficient in fundamental motor skills (FMS), which are the foundation for PA. As such, interventions are needed to increase PA and FMS in young children. This trial examined the effects of an environmental ("painted playgrounds") and capacity-building (written toolkit) intervention on child FMS, PA, and sedentary behavior at early childhood education (ECE) centers and examined feasibility. METHODS: In a randomized controlled trial, four ECE centers were randomly assigned to an intervention group or wait-list control. For intervention centers, stencils were spray painted adjacent to playgrounds and teachers were provided material for using stencils for FMS practice. Follow-up assessments were conducted six to eight weeks after baseline. Time spent in PA and sedentary behavior was assessed via accelerometry and FMS were evaluated using the Test of Gross Motor Development (TGMD-3) at baseline and follow-up. A repeated measures linear model was performed to test the effects of the painted playgrounds on the primary outcomes of interest. Feasibility was measured by stencil engagement via direct observation and satisfaction surveys. RESULTS: A total of 51 preschoolers completed baseline assessments (4.3±0.6 years; 43.1% male). There were no significant changes in PA or sedentary behavior (all confidence intervals contain 0) between control and intervention groups. Intervention children significantly improved ball skill, locomotor, and overall TGMD-3 percentile scores at follow-up (all (all confidence intervals contain 0), which was not observed in control group. However, there was no significant change in FMS between the control and intervention groups (confidence intervals contain 0). For stencil use, boys and girls interacted with different stencils during their free play. Directors and teachers reported children incorporated academic concepts and initiated games, and teachers prompted more PA opportunities on the playground. CONCLUSIONS: This intervention did not show statistically significant changes in children's PA, FMS, or sedentary behavior compared to a control group; however, small FMS improvements for the intervention group were found from baseline to follow-up. Further work should examine intervention fidelity as well as inexpensive supplies, teacher training, or other strategies to increase preschool children's PA and improve FMS at ECE centers.

An examination of the relationships between the neighborhood social environment, adiposity, and cardiometabolic disease risk in adolescence: a cross-sectional study.

BACKGROUND: Disadvantaged neighborhood environments are a source of chronic stress which undermines optimal adolescent health. This study investigated relationships between the neighborhood social environment, specifically, chronic stress exposures, adiposity, and cardiometabolic disease risk factors among 288 Louisiana adolescents aged 10 to 16 years. METHODS: This cross-sectional study utilized baseline data from the Translational Investigation of Growth and Everyday Routines in Kids (TIGER Kids) study. Adolescent data were obtained using self-reported questionnaires (demographics and perceived neighborhood disorder), anthropometry, body imaging, and a blood draw while objective neighborhood data for the concentrated disadvantage index were acquired from the 2016 American Community Survey five-year block group estimates, 2012-2016. Multilevel linear regression models were used to examine whether neighborhood concentrated disadvantage index and perceived neighborhood disorder were associated with body mass index, waist circumference, body fat, adipose tissue, blood pressure, and lipids. We performed multilevel logistic regression to determine the odds of elevated adiposity and cardiometabolic disease risk for adolescents living in neighborhoods with varying levels of neighborhood concentrated disadvantage and disorder. RESULTS: Adolescents living in neighborhoods with higher disadvantage or disorder had greater waist circumference and total percent body fat compared to those in less disadvantaged and disordered neighborhoods (p for trend < 0.05). Neighborhood disadvantage was also positively associated with percentage of the 95th Body Mass Index percentile and visceral abdominal adipose tissue mass while greater perceived neighborhood disorder was related to higher trunk fat mass and diastolic blood pressure (p for trend < 0.05). Living in the most disadvantaged was associated with greater odds of obesity (OR: 2.9, 95% CI:1.3, 6.5) and being in the top tertile of body fat mass (OR: 3.0, 95% CI: 1.4, 6.6). Similar results were found with neighborhood disorder for odds of obesity (OR: 2.1, 95% CI:1.1, 4.2) and top tertile of body fat mass (OR: 2.1, 95% CI:1.04, 4.1). CONCLUSIONS: Neighborhood social environment measures of chronic stress exposure were associated with excess adiposity during adolescence, and relationships were most consistently identified among adolescents living in the most disadvantaged and disordered neighborhoods. Future studies should account for the influences of the neighborhood environment to stimulate equitable improvements in adolescent health. CLINICAL TRIALS REGISTRATION: # NCT02784509.

Physiologic hormone administration improves HbA1C in Native Americans with type 2 diabetes: A retrospective study and review of insulin secretion and action.

Insulin is secreted in pulses from pancreatic beta-cells, and these oscillations maintain fasting plasma glucose levels within a narrow normal range. Within islets, beta-cells exhibit tight synchronization of regular oscillations. This control circuit is disrupted in type 2 diabetes, and irregularities in pulse frequency and amplitude occur. The prevalence of type 2 diabetes is three times higher in American Indian and Native Alaskans compared to Whites, and their genetic ancestry is associated with low beta-cell function. Obesity in this population compounds their vulnerability to adverse outcomes. The purpose of this article is to review insulin secretion and action and its interaction with race. We also present the results from a 6-month retrospective chart review of metabolic outcomes following intravenous physiologic hormone administration to 10 Native Americans. We found reductions in hemoglobin A1C (baseline: 9.03% ± 2.08%, 6 months: 7.03% ± 0.73%, p = 0.008), fasting glucose (baseline: 176.0 ± 42.85 mg/dL, 6 months: 137.11 ± 17.05 mg/dL, p = 0.02), homeostatic model assessment of insulin resistance (baseline: 10.39 ± 4.66, 6 months: 7.74 ± 4.22, p = 0.008), and triglycerides (baseline: 212.20 ± 101.44, 6 months: 165.50 ± 76.48 mg/dL, p = 0.02). Physiologic hormone administration may improve components of the metabolic syndrome. The therapy warrants investigation in randomized controlled trials.

A scalable, virtual weight management program tailored for adults with type 2 diabetes: effects on glycemic control.

BACKGROUND: The objective was to test the efficacy of a scalable, virtually delivered, diabetes-tailored weight management program on glycemic control in adults with type 2 diabetes (T2D). METHODS: This was a single arm, three-site clinical trial. Participants had baseline HbA1c between 7-11% and BMI between 27-50 kg/m2. Primary outcome was change in HbA1c at 24 weeks. Secondary outcomes were changes in body weight, waist circumference, the Diabetes Distress Scale (DDS), quality of life (IWQOL-L), and hunger (VAS). Generalized linear effects models were used for statistical analysis. RESULTS: Participants (n = 136) were 56.8 ± 0.8 y (Mean ± SEM), 36.9 ± 0.5 kg/m2, 80.2% female, 62.2% non-Hispanic white. Baseline HbA1c, weight, and total DDS score were 8.0 ± 0.09%, 101.10 ± 1.47 kg, and 2.35 ± 0.08, respectively. At week 24, HbA1c, body weight, and total DDS decreased by 0.75 ± 0.11%, 5.74 ± 0.50%, 0.33 ± 0.10 units, respectively (all p < 0.001). Also, at week 24, quality of life increased by 9.0 ± 1.2 units and hunger decreased by 14.3 ± 2.4 units, (both p < 0.0001). CONCLUSIONS: The scalable, virtually delivered T2D-tailored weight management program had favorable and clinically meaningful effects on glycemic control, body weight, and psychosocial outcomes.

Safety and Tolerability of Whole Soybean Products: A Dose-Escalating Clinical Trial in Older Adults with Obesity.

Soybean products have nutrients, dietary fiber, and phytoalexins beneficial for cardiovascular and overall health. Despite their high consumption in Asian populations, their safety in Western diets is debated. We conducted a dose-escalating clinical trial of the safety and tolerability of soybean products in eight older adults (70-85 years) with obesity. Whole green soybean pods grown under controlled conditions were processed to flour (WGS) at the United States Department of Agriculture using common cooking techniques such as slicing and heat treatment. WGS incorporated into food products was consumed at 10 g, 20 g, and 30 g/day for one week at each dose. The gastrointestinal outcomes, clinical biomarkers, and adverse events were evaluated. We explored the stimulation of phytoalexin (glyceollin) production in live viable soybean seeds (LSS-G). We compared the compositions of WGS and LSS-G with commercial soybean flour and its fermented and enzymatically hydrolyzed forms. We found that although 30 g WSG was well-tolerated, and it made participants feel full. Our processing produced glyceollins (267 µg/g) in LSS-G. Processing soybean flour decreased the iron content, but reduced the oligosaccharides, which could attenuate flatulence. Providing soybean flour at <30 g/day may be prudent for overall health and to prevent the exclusion of other food groups and nutrients in older adults with obesity.

Effect of sleep restriction on insulin sensitivity and energy metabolism in postmenopausal women: A randomized crossover trial.

OBJECTIVE: The aim of this study was to investigate the effect of sleep restriction (SR) on insulin sensitivity and energy metabolism in postmenopausal women. METHODS: In a randomized crossover trial, 14 women underwent four nights of habitual sleep (HS, 100% normal sleep) and SR (60% of HS) while following a eucaloric diet. Outcomes included the following: (1) insulin sensitivity by hyperinsulinemic-euglycemic clamp, defined as the glucose infusion rate (GIR); (2) resting metabolism and substrate oxidation by indirect calorimetry; and (3) glucose, insulin, and C-peptide concentrations following a standard meal test. RESULTS: Nine postmenopausal women (mean [SD], age 59 [4] years, BMI 28.0 [2.6] kg/m2 ) were analyzed. Accelerometer-determined total time in bed was 8.4 ± 0.6 hours during HS versus 5.0 ± 0.4 hours during SR (38% reduction, p < 0.0001). SR reduced low-dose insulin GIR by 20% (HS: 2.55 ± 0.22 vs. SR: 2.03 ± 0.20 mg/kg/min; p = 0.01) and high-dose insulin GIR by 12% (HS: 10.48 ± 0.72 vs. SR: 9.19 ± 0.72 mg/kg/min; p < 0.001). SR reduced fat oxidation during high-dose insulin infusion (p < 0.01), and it did not alter resting energy metabolism. CONCLUSIONS: Four nights of SR reduced insulin sensitivity and fat oxidation in postmenopausal women. These findings underscore the role of insufficient sleep in metabolic dysfunction following menopause. Larger trials investigating how sleep disturbances cause metabolic dysfunction during menopause are needed across all stages of menopause.

Metabolic Adaptations and Substrate Oxidation are Unaffected by Exogenous Testosterone Administration during Energy Deficit in Men.

INTRODUCTION/PURPOSE: The effects of testosterone on energy and substrate metabolism during energy deficit are unknown. The objective of this study was to determine the effects of weekly testosterone enanthate (TEST; 200 mg·wk -1 ) injections on energy expenditure, energy substrate oxidation, and related gene expression during 28 d of energy deficit compared with placebo (PLA). METHODS: After a 14-d energy balance phase, healthy men were randomly assigned to TEST ( n = 24) or PLA ( n = 26) for a 28-d controlled diet- and exercise-induced energy deficit (55% below total energy needs by reducing energy intake and increasing physical activity). Whole-room indirect calorimetry and 24-h urine collections were used to measure energy expenditure and energy substrate oxidation during balance and deficit. Transcriptional regulation of energy and substrate metabolism was assessed using quantitative reverse transcription-polymerase chain reaction from rested/fasted muscle biopsy samples collected during balance and deficit. RESULTS: Per protocol design, 24-h energy expenditure increased ( P < 0.05) and energy intake decreased ( P < 0.05) in TEST and PLA during deficit compared with balance. Carbohydrate oxidation decreased ( P < 0.05), whereas protein and fat oxidation increased ( P < 0.05) in TEST and PLA during deficit compared with balance. Change (∆; deficit minus balance) in 24-h energy expenditure was associated with ∆activity factor ( r = 0.595), but not ∆fat-free mass ( r = 0.147). Energy sensing (PRKAB1 and TP53), mitochondria (TFAM and COXIV), fatty acid metabolism (CD36/FAT, FABP, CPT1b, and ACOX1) and storage (FASN), and amino acid metabolism (BCAT2 and BCKHDA) genes were increased ( P < 0.05) during deficit compared with balance, independent of treatment. CONCLUSIONS: These data demonstrate that increased physical activity and not exogenous testosterone administration is the primary determinate of whole-body and skeletal muscle metabolic adaptations during diet- and exercise-induced energy deficit.

Low-Energy Dense Potato- and Bean-Based Diets Reduce Body Weight and Insulin Resistance: A Randomized, Feeding, Equivalence Trial.

We evaluated the effect of diets low in energy density (1 kcal/g) and high in either potatoes (Potato) or pulses (Bean) on blood glucose control in participants with insulin resistance. We hypothesized that the Potato and Bean diets would have equivalent effects. This was an 8-week randomized, parallel design, controlled feeding study comparing Potato and Bean diets (50-55% carbohydrate, 30-35% fat, 15-20% protein). Equivalence was prespecified as the mean change in the blood glucose concentration for Potato that was within ±20% of the Bean diet. Thirty-six participants (age: 18-60 years, body mass index: 25-40 kg/m2) with insulin resistance (homeostatic model assessment of insulin resistance [HOMA-IR] >2) were enrolled. Body weight was measured, and subjects underwent a mixed meal tolerance test at baseline and after 8 weeks. Intent-to-treat (ITT) and completer analyses were conducted. Equivalence between the two diets in the area under the curve for serum glucose was attained within ±10%, but the reduction from baseline was not statistically significant. For the Bean diet, insulin (area under the response curve: -2136.3 ± 955.5 mg/[dL∙min], P = .03) and HOMA-IR (-1.4 ± 0.6, P = .02) were lower compared with baseline. ITT and completer analyses were similar, except that HOMA-IR was also reduced by the Potato diet (-1.3 ± 0.6, P < .05). Compliance with the diets was 87-88%, and body weight was reduced in both diets (Potato: -5.6% ± 0.6%; Bean: -4.1% ± 0.6%, P < .001) with no significant difference between the two diets. Potato and Bean diets low in energy density were equally effective in reducing insulin resistance and promoting weight loss in individuals with impaired blood glucose control. Clinical Trial: The trial was registered with ClinicalTrials.gov Identifier: NCT04203238.

Testosterone undecanoate administration prevents declines in fat-free mass but not physical performance during simulated multi-stressor military operations.

Male military personnel conducting strenuous operations experience reduced testosterone concentrations, muscle mass, and physical performance. Pharmacological restoration of normal testosterone concentrations may attenuate performance decrements by mitigating muscle mass loss. Previously, administering testosterone enanthate (200 mg/wk) during 28 days of energy deficit prompted supraphysiological testosterone concentrations and lean mass gain without preventing isokinetic/isometric deterioration. Whether administering a practical dose of testosterone protects muscle and performance during strenuous operations is undetermined. The objective of this study was to test the effects of a single dose of testosterone undecanoate on body composition and military-relevant physical performance during a simulated operation. After a 7-day baseline phase (P1), 32 males (means ± SD; 77.1 ± 12.3 kg, 26.5 ± 4.4 yr) received a single dose of either testosterone undecanoate (750 mg; TEST) or placebo (PLA) before a 20-day simulated military operation (P2), followed by a 23-day recovery (P3). Assessments included body composition and physical performance at the end of each phase and circulating endocrine biomarkers throughout the study. Total and free testosterone concentrations in TEST were greater than PLA throughout most of P2 (P < 0.05), but returned to P1 values during P3. Fat-free mass (FFM) was maintained from P1 to P2 in TEST (means ± SE; 0.41 ± 0.65 kg, P = 0.53), but decreased in PLA (-1.85 ± 0.69 kg, P = 0.01) and recovered in P3. Regardless of treatment, total body mass and fat mass decreased from P1 to P2 (P < 0.05), but did not fully recover by P3. Physical performance decreased during P2 (P < 0.05) and recovered by P3, regardless of treatment. In conclusion, administering testosterone undecanoate before a simulated military operation protected FFM but did not prevent decrements in physical performance.NEW & NOTEWORTHY This study demonstrated that a single intramuscular dose of testosterone undecanoate (750 mg) administered to physically active males before a 20-day simulated, multi-stressor military operation increased circulating total and free testosterone concentrations within normal physiological ranges and spared FFM. However, testosterone administration did not attenuate decrements in physical performance across multiple measures of power, strength, anaerobic or aerobic capacity.

Infant Feeding Varies Across Eating Behavior and Feeding Modalities in Mothers With Low Income.

OBJECTIVE: To examine if eating behaviors in mothers with low income relate to attitudes toward infant feeding and whether associations differed between breastfeeding and formula-feeding mothers. DESIGN: Cross-sectional study. PARTICIPANTS: Forty postpartum women (aged ≥ 18 years, body mass index ≥ 25 and &lt; 40 kg/m²) in the Louisiana Women, Infants, and Children program participated in a telehealth postpartum intervention for health and weight loss. MAIN OUTCOME MEASURE(S): Maternal eating behaviors and infant feeding styles, assessed 6-8 weeks after birth (baseline) using validated questionnaires. ANALYSIS: Significance was detected using independent t tests, chi-square tests for independence, or linear models (P &lt; 0.05). RESULTS: Most mothers formula-fed (n = 27, 68%). In formula-feeding mothers, maternal disinhibition and perceived hunger were positively associated with restrictive infant feeding (ß = 0.41, P &lt;0.001 and ß = 0.41, P = 0.001, respectively). These relationships were significantly higher (Δ = -0.85, P = 0.006 and Δ = -0.59, P = 0.003, respectively) than among breastfeeding mothers. Comparatively, pressuring/overfeeding was lower in formula-feeding mothers than among breastfeeding mothers with dietary restraint (Δ slopes: 1.06, P = 0.02). CONCLUSIONS AND IMPLICATIONS: In this cohort of mothers with low income, maternal eating behavior was associated with infant feeding styles only when feeding modality was considered. Mothers may benefit from education on how their eating behaviors can influence their infants and children.

Effects of acute arginine supplementation on neuroendocrine, metabolic, cardiovascular, and mood outcomes in younger men: A double-blind, placebo-controlled trial.

OBJECTIVES: Arginine is an amino-acid supplement and precursor for nitric-oxide synthesis, which affects various biologic processes. The objective of this study was to determine the effects of arginine supplementation on growth hormone (GH) and metabolic parameters. METHODS: Thirty physically active, healthy men (age 18-39 y; body mass index: 18.5-25 kg/m2) were randomized in a double-blind, placebo-controlled, crossover trial. Arginine (10 g) and placebo (0 g) beverages were consumed after an overnight fast. Blood samples were collected at baseline and 1.5, 3.0, and 24 h after supplementation. The primary outcomes were serum GH and metabolomics. Also, amino acids, glucose, insulin, triacylglycerols, thyroid hormones, testosterone, cortisol, dehydroepiandrosterone, and mood state were assessed. Individuals with detectable increases in GH were analyzed separately (responders: n = 16; < 0.05 ng/mL at 1.5 h). Repeated-measure analyses of variance estimated the treatment effects at each timepoint. RESULTS: Arginine levels increased at 1.5 h (146%) and 3.0 h (95%; P ≤ 0.001) and GH (193%) and thyroid-stimulating hormone (TSH; 10%) levels at 24 h (P < 0.05) after arginine versus placebo consumption. Arginine versus placebo increased glucose levels at 1.5 h (5%) and 3.0 h (3%; P ≤ 0.001). Arginine versus placebo did not affect other dependent measures, including mood state (P > 0.05), but changes in the urea, glutamate, and citric-acid pathways were observed. Among responders, arginine versus placebo increased GH at 1.5 h (37%), glucose at 1.5 h (4%) and 3.0 h (4%), and TSH at 24 h (9%; P < 0.05). Responders had higher levels of benzoate metabolites at baseline and 1.5 h, and an unknown compound (X-16124) at baseline, 1.5 h, and 24 h that corresponds to a class of gut microbes (P < 0.05). CONCLUSIONS: Arginine supplementation modestly increased GH, glucose, and TSH levels in younger men. Responders had higher benzoate metabolites and an unknown analyte attributed to the gut microbiome. Future studies should examine whether the increased prevalence of these gut microorganisms corresponds with GH response after arginine supplementation.

Participant Perspectives Concerning Resuming Clinical Research in the Era of COVID-19.

Background: The coronavirus disease 2019 (COVID-19) pandemic caused a shutdown of clinical research but offered a unique opportunity to understand attitudes and motivations around contributing to clinical research and resuming in-person visits during a pandemic. Methods: We conducted an anonymous survey study at Pennington Biomedical Research Center (PBRC) in participants returning for in-person visits from May 26, 2020 to August 11, 2020 and in people who previously expressed interest in research via an online Research Electronic Data Capture (REDCap) survey from August 6, 2020 to September 11, 2020. The survey gathered demographic information and presented statements that required answers on a scale of 1 (absolutely disagree) to 10 (absolutely agree). Two hundred fifty-one people completed paper surveys in-person while 1,537 people completed the survey online. Results: Online participants were more likely to be female (75.2% vs. 56.8%), more likely to have had COVID-19 symptoms (19.6% vs. 5.2%), and more likely to know someone with COVID-19 (72.7% vs. 49.4%). More people who came in-person thought they were low risk for severe COVID-19 compared to those who filled out the survey online (52.2% vs. 38.4%, P = 0.0002). More people who completed the survey online preferred to do as many study visits over the phone or internet as possible (37.8% vs. 22.7%, P < 0.0001). More people who came in-person agreed that clinical research is even more important than before COVID-19 (54.2% vs. 44.3%, P = 0.0035). Conclusions: The majority of people felt that clinical research is important because of the health benefits received and because it may help others. These data may provide important considerations in the planning of future studies in the era of COVID-19.

A higher proportion of small adipocytes is associated with increased visceral and ectopic lipid accumulation during weight gain in response to overfeeding in men.

BACKGROUND: Adipose tissue (AT) expansion occurs by hypertrophy (increase in size) and hyperplasia (increase in number) of adipocytes. The AT expandability hypothesis postulates that impaired subcutaneous AT expansion leads to ectopic fat accretion, contributing to impaired metabolic health. The role of adipogenesis as a contributing factor is debatable. SUBJECTS/METHODS: In the present analysis, we assess changes in adipocyte size distribution in relation to changes in ectopic fat accretion in response to 8-weeks of overfeeding in 22 men (28 ± 5.4 years; BMI 25.5 ± 2.3 kg/m2) who were fed 40% over their baseline energy requirements. RESULTS: Participants gained 6.7 ± 2.1 kg. The percentage of small adipocytes (p = 0.03) and the peak diameter of large adipocytes (p = 0.01) increased after overfeeding. At baseline, the percentage of small adipocytes was positively correlated with % body fat (p = 0.03), SAT mass (p = 0.01), VAT mass (p = 0.02), VAT:TAT (p = 0.05), and IHL (p = 0.09; trend). The relative (percent) change in small adipocytes was positively associated with the increase in whole-body fat (p = 0.001), VAT mass (p = 0.0003), VAT:TAT (p = 0.01), and IHL (p = 0.007) in response to overfeeding. CONCLUSIONS: These findings, surprisingly, indicate that during substantial weight gain, an increase in small adipocytes (suggesting hyperplastic expansion) is associated with impaired (not improved) metabolic health outcomes, specifically visceral and ectopic fat accumulation. CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov Identifier- NCT01672632.

mHealth Intervention for Motor Skills: A Randomized Controlled Trial.

BACKGROUND AND OBJECTIVES: Children's motor skills are a critical foundation for physical activity. The objective was to determine the effectiveness and feasibility of a mobile app-based intervention delivered to parents to improve preschoolers' motor skills. METHODS: This randomized controlled trial randomly assigned children to : (1) Motor Skills, including instructional lessons, peer modeling videos, behavioral scaffolding, and structured activities or 2) Free Play. Both groups received a 12-week app-based intervention informed by social cognitive theory to deliver 12 hours (12-minutes per day, 5× per week) of instruction. The children were aged 3 to 5 y; parents and children had no mobility impairments. The primary outcome variables were children's motor skills percentile score assessed with the Test of Gross Motor Development, third edition (TGMD-3) at baseline, end-of-intervention (week 12), and follow-up (week 24); and feasibility and acceptability. RESULTS: Seventy-two children (4.0 ± 0.8 y) participated. Between baseline and week 12, children in the Motor Skills condition significantly improved total TGMD-3 percentile (+13.7 Motor Skills vs -5.3 Free Play, P < .01), locomotor skills percentile (+15.5 Motor Skills vs -4.8 Free Play, P < .01), and ball skills percentile (+8.3 Motor Skills vs -7.3 Free Play, P < .01) compared with children in the comparator group. Significant differences were sustained at follow-up (week 24). Adherence did not significantly differ between conditions (71% for Motor Skills; 87% for Free Play). Parents in both arms reported high scores on satisfaction, helpfulness, and ease of use. CONCLUSIONS: Clinicians and educators may encourage parents to enhance their child's motor skills through structured at-home programs.