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The COVID-19 pandemic has changed routines and habits, raising stress and anxiety levels of individuals worldwide. The goal of this qualitative study was to advance the understanding of how pandemic-related changes affected sleep, diet, physical activity (PA), and stress among adults. We conducted semi-structured, qualitative interviews with 185 participants and selected 33 interviews from a represented sample based on age, race, and gender for coding and analysis of themes. After coding for thematic analysis, results demonstrated four primary themes: sleep, diet, PA, and stress. Sleep sub-themes such as poorer sleep quality were reported by 36% of our participants, and 12% reported increased an frequency of vivid dreams and nightmares. PA was decreased in 52% of our participants, while 33% experienced an increase and 15% experienced no change in PA. Participants also reported having an improved diet, mostly among women. Stress was elevated in 79% of our participants and was more likely to be discussed by women. Many participants reported how stress was involved in precipitating health behavior change, especially for sleep. Increased stress was also linked to elevated anxiety and depression among participants. The results of this qualitative study demonstrate how managing stress could have a beneficial effect on promoting health behaviors and mental health during the COVID-19 pandemic and beyond. [ABSTRACT FROM AUTHOR]

Purpose: This study aimed to determine if energy intake and appetite regulation differ in response to an acute bout of resistance exercise (REx) versus aerobic exercise (AEx). Methods: Physically inactive adults (n = 24, 35% ± 2% body fat, 50% female) completed three conditions: AEx (walking at 65%-70% heart rate max for 45 min), REx (1 set to failure of 12 exercises), and sedentary control (SED). Each condition was initiated in the post-prandial state (35 min after breakfast). Appetite (visual analog scale for hunger, satiety, and prospective food consumption) and hormones (ghrelin, peptide YY (PYY), andglucagon-likepeptide-1 (GLP-1)) were measured before and 30,90,120,150, and 180 min after a standardized breakfast. Area under the curve was calculated using the trapezoid method. Ad libitum energy intake was evaluated at a lunch meal after the 180-min measurements. Results: No differences in ad libitum energy intake (REx, 991 ± 68; AEx, 937 ±65; SED, 944 ± 76 kcal; P = 0.50) or appetite ratings (all, P > 0.05) were detected. The area under the curve for ghrelin, PYY, and GLP-1 were all lower after REx versus AEx (ghrelin: 130,737 ± 4928 for REx; 143,708 ± 7500 for AEx (P = 0.006); PYY: 20,540 ± 1177 for REx, 23,812 ± 1592 for AEx (P = 0.001); and GLP-1: 1314 ±93 for REx, 1615 ± 110 for AEx (P = 0.013)). Neither exercise condition significantly differed from SED. Conclusions: Acute REx lowers both orexigenic (ghrelin) and anorectic (PYY and GLP-1) gut peptides compared with acute AEx. Ad libitum energy intake did not increase compared with SED in either exercise condition, indicating both exercise modalities have appetite and energy intake suppressing effects. Future work is needed to determine if exercise of differing modalities influences chronic appetite regulation. [ABSTRACT FROM AUTHOR]

The use of classic nonparametric tests (cNPTs), such as the Kruskal–Wallis and Mann–Whitney U tests, in the presence of unequal variance for between-group comparisons of means and medians may lead to marked increases in the rate of falsely rejecting null hypotheses and decreases in statistical power. Yet, this practice remains prevalent in the scientific literature, including nutrition and obesity literature. Some nutrition and obesity studies use a cNPT in the presence of unequal variance (i.e. heteroscedasticity), sometimes because of the mistaken rationale that the test corrects for heteroscedasticity. Herein, we discuss misconceptions of using cNPTs in the presence of heteroscedasticity. We then discuss assumptions, purposes, and limitations of 3 common tests used to test for mean differences between multiple groups, including 2 parametric tests: Fisher's ANOVA and Welch's ANOVA; and 1 cNPT: the Kruskal–Wallis test. To document the impact of heteroscedasticity on the validity of these tests under conditions similar to those used in nutrition and obesity research, we conducted simple simulations and assessed type I error rates (i.e. false positives, defined as incorrectly rejecting the null hypothesis). We demonstrate that type I error rates for Fisher's ANOVA, which does not account for heteroscedasticity, and Kruskal–Wallis, which tests for differences in distributions rather than means, deviated from the expected significance level. Greater deviation from the expected type I error rate was observed as the heterogeneity increased, especially in the presence of an imbalanced sample size. We provide brief tutorial guidance for authors, editors, and reviewers to identify appropriate statistical tests when test assumptions are violated, with a particular focus on cNPTs. [ABSTRACT FROM AUTHOR]

Objective: Appetite responses to 3 days of overfeeding (OF) were examined as correlates of longitudinal weight change in adults classified as obesity prone (OP) or obesity resistant (OR).Methods: OP (n = 22) and OR (n = 30) adults consumed a controlled eucaloric and OF diet (140% of energy needs) for 3 days, followed by 3 days of ad libitum feeding. Hunger and satiety were evaluated by visual analog scales. Ghrelin and peptide YY (PYY) levels were measured during a 24-hour inpatient visit on day 3. Body weight and composition were measured annually for 4.0 ± 1.3 years.Results: Dietary restraint and disinhibition were greater in OP than OR (mean difference: 3.5 ± 1.2 and 3.3 ± 0.9, respectively; P < 0.01) participants, and disinhibition was associated with longitudinal weight change (n = 48; r = 0.35; P = 0.02). Compared with the eucaloric diet, energy intake fell significantly in OR participants following OF (P = 0.03) but not in OP (P = 0.33) participants. Twenty-four-hour PYY area under the curve values increased with OF in OR (P = 0.02) but not in OP (P = 0.17) participants. Furthermore, changes in PYY levels with OF correlated with measured energy intake (r = -0.36; P = 0.01).Conclusions: Baseline disinhibition and PYY responses to OF differed between OP and OR adults. Dietary disinhibition was associated with 5-year longitudinal weight gain. Differences in appetite regulation may underlie differences in propensity for weight gain. [ABSTRACT FROM AUTHOR]

Background Regression to the mean (RTM) is a statistical phenomenon where initial measurements of a variable in a nonrandom sample at the extreme ends of a distribution tend to be closer to the mean upon a second measurement. Unfortunately, failing to account for the effects of RTM can lead to incorrect conclusions on the observed mean difference between the 2 repeated measurements in a nonrandom sample that is preferentially selected for deviating from the population mean of the measured variable in a particular direction. Study designs that are susceptible to misattributing RTM as intervention effects have been prevalent in nutrition and obesity research. This field often conducts secondary analyses of existing intervention data or evaluates intervention effects in those most at risk (i.e., those with observations at the extreme ends of a distribution). Objectives To provide best practices to avoid unsubstantiated conclusions as a result of ignoring RTM in nutrition and obesity research. Methods We outlined best practices for identifying whether RTM is likely to be leading to biased inferences, using a flowchart that is available as a web-based app at https://dustyturner.shinyapps.io/DecisionTreeMeanRegression/. We also provided multiple methods to quantify the degree of RTM. Results Investigators can adjust analyses to include the RTM effect, thereby plausibly removing its biasing influence on estimating the true intervention effect. Conclusions The identification of RTM and implementation of proper statistical practices will help advance the field by improving scientific rigor and the accuracy of conclusions. This trial was registered at clinicaltrials.gov as NCT00427193. [ABSTRACT FROM AUTHOR]

Background: Objective indicators of dietary intake (e.g., biomarkers) are needed to overcome the limitations of self-reported dietary intake assessment methods in adolescents. To our knowledge, no controlled feeding studies to date have evaluated the validity of urinary sodium, nitrogen, or sugar excretion as dietary biomarkers in adolescents.Objective: This investigation aimed to evaluate the validity of urinary sodium, nitrogen, and total sugars (TS) excretion as biomarkers for sodium, protein, and added sugars (AS) intake in nonobese adolescents.Methods: In a crossover controlled feeding study design, 33 adolescents [12-18 y of age, 47 ± 25th percentile (mean ± SD) of body mass index (BMI; in kg/m2) for age] consumed 5% AS [low added sugars (LAS)] and 25% AS [high added sugars (HAS)] isocaloric, macronutrient-matched (55% carbohydrate, 30% fat, and 15% protein) diets for 7 d each, in a randomly assigned order, with a 4-wk washout period between diets. On the final 2 d of each diet period, 24-h urine samples were collected. Thirty-two adolescents completed all measurements (97% retention).Results: Urinary sodium was not different from the expected 90% recovery (mean ± SD: 88% ± 18%, P = 0.50). Urinary nitrogen was correlated with protein intake (r = 0.69, P < 0.001), although it was below the 80% expected recovery (62% ± 7%, P < 0.001). Urinary TS values were correlated with AS intake during the HAS diet (r = 0.77, P < 0.001) and had a higher R2 value of 0.28 than did AS intake (R2 = 0.36). TS excretion differed between LAS (0.226 ± 0.09 mg/d) and HAS (0.365 ± 0.16 mg/d) feeding periods (P < 0.001).Conclusions: Urinary sodium appears to be a valid biomarker for sodium intake in nonobese adolescents. Urinary nitrogen is associated with protein intake, but nitrogen excretion rates were less than previously reported for adults, possibly owing to adolescent growth rates. TS excretion reflects AS at 25% AS intake and was responsive to the change in AS intake. Thus, urinary biomarkers are promising objective indicators of dietary intake in adolescents, although larger-scale feeding trials are needed to confirm these findings. This trial was registered at clinicaltrials.gov as NCT02455388. [ABSTRACT FROM AUTHOR]

Background Aerobic exercise interventions have been shown to result in alterations to dietary intake and non-exercise physical activity (PA). To date, the ability for resistance training (RT) to influence other health-related behaviors has not been examined. This study aimed to determine if initiation and maintenance of RT is associated with spontaneous changes in dietary quality and non-RT PA in adults with prediabetes. Methods Overweight/obese adults ( n = 170, BMI = 32.9 ± 3.8 kg·m 2 , age = 59.5 ± 5.5 years, 73% female) with prediabetes were enrolled in the 15-month Resist Diabetes trial. Participants completed a supervised 3-month RT initiation phase followed by a 6-month maintenance phase and a 6-month no-contact phase. Participants were not encouraged to change eating or non-RT PA behaviors. At baseline, and months 3, 9, and 15, three 24-hour diet recalls were collected to evaluate dietary intake and quality, the Aerobics Institute Longitudinal Study Questionnaire was completed to evaluate non-RT PA, and body mass, body composition (DXA), and muscular strength were measured. At months 3, 9, and 15 social cognitive theory (SCT) constructs were assessed with a RT Health Beliefs Questionnaire. Mixed effects models were used to assess changes in dietary intake and non-RT PA over the 15-month study period. Results Energy and carbohydrate intake decreased with RT initiation and maintenance phases (baseline to month 9: β = − 87.9, p = 0.015 and β = − 16.3, p < 0.001, respectively). No change in overall dietary quality (Healthy Eating Index [HEI]-2010 score: β = − 0.13, p = 0.722) occurred, but alterations in HEI-2010 sub-scores were detected. Maintenance of RT was accompanied by an increase in MET-min/week of total non-RT PA (month 3 to month 9: β = 146.2, p = 0.01), which was predicted by increased self-regulation and decreased negative outcome expectancies for RT (β = 83.7, p = 0.014 and β = − 70.0, p = 0.038, respectively). Conclusions Initiation and maintenance of RT may be a gateway behavior leading to improvements in other health-related behaviors. These results provide rationale for single-component lifestyle interventions as an alternative to multi-component interventions, when resources are limited. [ABSTRACT FROM AUTHOR]

PURPOSE: The novel coronavirus pandemic (COVID-19) has resulted in disruptions to daily routines, including physical activity (PA). PA is a behavior that could assist in both prevention of and recovery from SARS-CoV-2 infection. Therefore, the purpose of this study was to evaluate changes in PA and the factors that associate with PA during COVID-19 in a sample of adults from Utah. METHODS: Participants were a sample of 201 adults (52.7% Female; Age: 40.6±18.5 yrs; BMI: 26.7±5.8 kg/m2) living in the state of Utah who were given 3 sets of online questionnaires during the first 3 waves of the COVID-19 pandemic in the US (wave 1: April-July; wave 2: Aug-Sept; wave 3: Oct-Dec). Moderate-to-vigorous physical activity (MVPA) was self-reported at three study time points via the short form International Physical Activity Questionnaire (IPAQ). Self-efficacy for exercise (via the Self-Efficacy for Exercise Scale), self-reported COVID-19 related changes to work/occupation, and working from home were also examined in the relationship with MVPA. A general linear mixed-effects model was used to examine the associations between pandemic wave, self-efficacy, occupation change, and working from home status with MVPA. Effect modification was tested using interaction terms. RESULTS: Individuals who worked from home tended to have lower self-reported log-MVPA compared to those not working from home (b=-0.77; 95%CI= -1.31 - -0.23; p=0.005). However, those who reported only that their work was affected by the pandemic did not exhibit significantly higher or lower log-MVPA (p=0.67). Finally, those with high self-efficacy had higher log- MVPA compared to those with low self-efficacy (b=0.58; 95%CI= 0.04 - 1.12; p=0.034). CONCLUSIONS: These results suggest that MVPA during COVID-19 is affected by specific work-related variables and self-efficacy for PA. These findings can help to inform and establish interventions to improve health outcomes during and after global pandemics, such as COVID-19. [ABSTRACT FROM AUTHOR]

The δ13C value of blood is a novel proposed biomarker of added sugars (AS) intake. AS prediction equations using either a single- (δ13C) or dual-isotope model (δ13C and δ15N) were previously developed in an adult population with high AS intake living in southwest Virginia (reference group). The purpose of this investigation was to test the δ13C single- and δ13C and δ15N dual-isotope prediction equations for AS intake in adults with a lower mean AS intake and different demographic characteristics (test group). The blood samples for the reference (n = 257 for single-isotope, n = 115 for dual-isotope) and test groups (n = 56) were analyzed for δ13C and δ15N values using natural abundance stable isotope mass spectrometry and were compared to reported dietary AS intake. When the δ13C single-isotope equation was applied to the test group, predicted AS intake was not significantly different from reported AS intake (mean difference ± standard error = −3.6 ± 5.5 g, Z = −0.55, p = 0.51). When testing the dual-isotope equation, predicted AS was different from reported AS intake (mean difference ± SEM = 13.0 ± 5.4 g, Z = −2.95, p = 0.003). δ13C value was able to predict AS intake using a blood sample within this population subset. The single-isotope prediction equation may be an alternative method to assess AS intake and is more objective, cost-feasible, and efficient than traditional dietary assessment methods. However, more research is needed to assess this biomarker with rigorous study designs such as controlled feeding. [ABSTRACT FROM AUTHOR]

The study objective was to validate a food frequency and lifestyle questionnaire (FFLQ) to assess vitamin D intake and lifestyle factors affecting status. Methods: Data collected previously during the fall (n = 86), winter (n = 49), and spring (n = 67) in collegiate-athletes (Study 1) and in active adults (n = 123) (Study 2) were utilized. Study 1: Vitamin D intake and ultraviolet B exposure were estimated using the FFLQ and compared to serum 25(OH)D concentrations via simple correlation and linear regression modeling. Study 2: Vitamin D intake from food was estimated using FFLQ and compared to vitamin D intake reported in 7-Day food diaries via paired t-test and Bland–Altman analysis. Results: Study 1: Serum 25(OH)D was not associated with vitamin D intake from food, food plus supplements, or sun exposure, but was associated with tanning bed use (r = 0.39) in spring, supplement use in fall (r = 0.28), and BMI (body mass index) (r = −0.32 to −0.47) across all seasons. Serum 25(OH)D concentrations were explained by BMI, tanning bed use, and sun exposure in fall, (R = 0.42), BMI in winter (R = 0.32), and BMI and tanning bed use in spring (R = 0.52). Study 2: Estimated Vitamin D intake from food was 186.4 ± 125.7 via FFLQ and 148.5 ± 228.2 IU/day via food diary. There was no association between intake estimated by the two methodologies (r = 0.12, p < 0.05). Conclusions: FFLQ-estimated vitamin D intake was not associated with serum 25(OH)D concentration or food-record-estimated vitamin D intake. Results highlight the difficulty of designing/utilizing intake methodologies for vitamin D, as its status is influenced by body size and both endogenous and exogenous (dietary) sources. [ABSTRACT FROM AUTHOR]

Bariatric surgery is associated with significant and sustained weight loss and improved metabolic outcomes. It is unclear if weight loss alone is the main mechanism of improved metabolic health. The purpose of this trial was to compare indices of appetite regulation, insulin sensitivity and energy intake (EI) between participants achieving 10 kg of weight loss via Roux‐en‐Y Gastric Bypass (RYGB) or dietary restriction (DIET); intake of a very low calorie liquid diet (800 kcal/d; 40% protein, 40% fat, 20% carbohydrate that matched the post‐RYGB dietary protocol). Adults qualifying for bariatric surgery were studied before and after 10 kg of weight loss (RYGB [n = 6]) or DIET [n = 17]). Appetite (hunger, satiety, and prospective food consumption [PFC]), appetite–related hormones, and metabolites (ghrelin, PYY, GLP‐1, insulin, glucose, free fatty acids [FFA], and triglycerides [TG]) were measured in the fasting state and every 30 min for 180 min following breakfast. Participants were provided lunch to evaluate acute ad libitum EI, which was similarly reduced in both groups from pre to post weight loss. Fasting ghrelin was reduced to a greater extent following RYGB compared to DIET (P = 0.04). Area under the curve (AUC) for ghrelin (P = 0.01), hunger (P < 0.01) and PFC (P < 0.01) increased after DIET compared to RYGB, following 10 kg weight loss. Satiety AUC increased after RYGB and decreased after DIET (P < 0.01). Glucose and insulin (fasting and AUC) decreased in both groups. FFA increased in both groups, with a greater increase in AUC seen after RYGB versus DIET (P = 0.02). In summary, appetite–related indices were altered in a manner that, if maintained, may promote a sustained reduction in energy intake with RYGB compared to DIET. Future work with a larger sample size and longer follow‐up will be important to confirm and extend these findings. RYGB altered appetite indices in a manner favoring continued energy restriction. DIET altered appetite indices in a manner favoring increased energy intake. Short‐term weight loss improved insulin sensitivity similarly in RYGB versus DIET. [ABSTRACT FROM AUTHOR]

Prediabetes is associated with low-grade chronic inflammation that increases the risk for developing type 2 diabetes (T2D) and cardiovascular disease (CVD). An elevated lipopolysaccharide concentration, associated with dysbiosis of the intestinal microbiota, has been implicated in the development of both T2D and CVD. Selective modulation of the intestinal microbiota with prebiotics reduces intestinal permeability and endotoxin concentrations, inflammation, and metabolic dysfunction in rodents. The effect of prebiotic supplementation on cardio-metabolic function in humans at risk for T2D is not known. The primary aim of this trial is to determine the influence of prebiotic supplementation with inulin on insulin sensitivity and skeletal muscle metabolic flexibility in adults at risk for T2D. We hypothesize that prebiotic supplementation with inulin will improve insulin sensitivity and skeletal muscle metabolic flexibility. We will randomize 48 adults (40–75 yrs) with prediabetes or a score ≥ 5 on the American Diabetes Association (ADA) risk screener to 6 weeks of prebiotic supplementation with inulin (10 g/day) or placebo. Subjects will be provided with all food for the duration of the study, to avoid potential confounding through differences in dietary intake between individuals. Intestinal permeability, serum endotoxin concentrations, insulin sensitivity, skeletal muscle metabolic flexibility, endothelial function, arterial stiffness, and fecal bacterial composition will be measured at baseline and following treatment. The identification of prebiotic supplementation with inulin as an efficacious strategy for reducing cardio-metabolic risk in individuals at risk of T2D could impact clinical practice by informing dietary recommendations and increasing acceptance of prebiotics by the scientific and medical community. [ABSTRACT FROM AUTHOR]

The purpose of the current study was to examine the influence of “time” on isometric elbow flexion torque, body temperature and muscle size without interrupting the sleep wake cycle in college aged males. Two hours following the participants normal wake time, oral temperature was measured, followed by muscle thickness of the upper and lower body using ultrasound, as well as elbow flexor torque via a maximal voluntary contraction (MVC). Measurements were repeated every 2 h for 12 h (Time points 1–7). To examine the repeatability of the rhythm, participants returned and completed the same procedures as before within 14 days of their first circadian visit (Circadian visit 2). There was no time × day interaction for body temperature (p = 0.29), nor were there main effects for time (p = 0.15) or day (p = 0.74). For MVC, there was no time × day interaction (p = 0.93) or main effect for day (p = 0.50), however, there was a main effect for time (p = 0.01). MVC at time points 1 (86.4 ± 6.4 Nm) and 2 (87.1 ± 6.2 Nm) was greater than time points 4 (84.2 ± 6.6 Nm) and 6 (83.4 ± 6.8 Nm, p < 0.05). Additionally, time point 5 MVC was greater than time point 4. For upper body muscle thickness, there was no time × day interaction (p = 0.34), nor was there a main effect for day (p = 0.38), or time (p = 0.06). For lower body muscle thickness, there was no time × day interaction (p = 0.57), nor was there a main effect for day (p = 0.75), or time (p = 0.13). Cosinor analyses revealed no group level rhythms for oral temperature, muscle thickness or strength (p > 0.05), however, there were some individual rhythms noted for muscle thickness and strength. Results suggest that, when accounting for an individuals normal wake time, circadian rhythms of strength, temperature and muscle thickness are not apparent in most individuals. [ABSTRACT FROM AUTHOR]

• Sex-based differences in ratings of hunger following acute exercise (EX) exist. • Hormonal indices of appetite do not differ between men and women following acute EX. • Relative energy intake following EX does not differ between men and women. • The relationship between hunger and energy intake in women may be dysregulated. • Acute EX may increase perceived hunger in women and decrease perceived hunger in men. To compare energy intake (EI) and appetite regulation responses between men and women following acute bouts of aerobic (AEx), resistance exercise (REx), and a sedentary control (CON). Men and women (n = 24; 50% male) with overweight/obesity, matched on age (32.3 ± 2 vs. 36.8 ± 2 yrs, p = 0.14) and BMI (28.1 ± 1.2 vs 29.0 ± 1.5 kg/m2, p = 0.64) completed 3 conditions: 1) AEx (65–70% of age-predicted maximum heart rate for 45 min); 2) REx (1-set to failure on 12 exercises); and 3) CON. Each condition was initiated in the post-prandial state (35 min following consumption of a standardized breakfast). Appetite (visual analog scale for hunger, satiety, and prospective food consumption [PFC]) and hormones (ghrelin, PYY, and GLP-1) were measured in the fasted state and every 30 min post-prandially for 3 h. Post-exercise ad libitum EI at the lunch meal was also measured. Men reported higher levels of hunger compared to women across all study conditions (AEx: Men: 7815.00 ± 368.3; Women: 5428.50 ± 440.0 mm x 180 min; p = 0.025; REx: Men: 7110.00 ± 548.4; Women: 6086.25 ± 482.9 mm x 180 min; p = 0.427; CON: Men: 8315.00 ± 429.8; Women: 5311.25 ± 543.1 mm x 180 min; p = 0.021) and consumed a greater absolute caloric load than women at the ad libitum lunch meal (AEx: Men: 1021.6 ± 105.4; Women: 851.7 ± 70.5 kcals; p = 0.20; REx: Men: 1114.7 ± 104.0; Women: 867.7 ± 76.4 kcals; p = 0.07; CON: Men: 1087.0 ± 98.8; Women: 800.5 ± 102.3 kcals; p = 0.06). However, when adjusted for relative energy needs, there was no difference in relative ad libitum EI observed between men and women. No differences in Area Under the Curve for Satiety, PFC, ghrelin, PYY, and GLP-1 were noted between men and women following acute exercise (all p > 0.05). These data suggest that women report lower ratings of appetite following an acute bout of exercise or sedentary time when compared to men, yet have similar relative EI. Future work is needed to examine whether sex-based differences in appetite regulation and EI are present with chronic exercise of differing modalities. [ABSTRACT FROM AUTHOR]

Introduction/purpose: A reduction in nonexercise physical activity (NEPA) after exercise may reduce the effectiveness of exercise interventions on weight loss in adults with overweight or obesity. Aerobic exercise (AEx) and resistance exercise (REx) may have different effects on NEPA. The purpose of this secondary analysis was to examine the effect of a single bout of AEx or REx on NEPA and sedentary behavior in inactive adults with overweight or obesity., Methods: Adults with overweight or obesity ( n = 24; 50% male; age, 34.5 ± 1.5 yr; body mass index, 28.5 ± 0.9 kg·m -2 ) not meeting current physical activity guidelines completed a single 45-min bout of AEx, REx, or a sedentary control on different days in random order. After each condition, participants' NEPA was recorded for 84 h by accelerometer. Time spent sedentary and in light, moderate, and vigorous physical activity; steps; metabolic equivalent of task (MET)-hours; and sit-to-stand transitions were calculated using activity count data., Results: No differences were observed in the percent of waking time spent sedentary and in light, moderate, and vigorous activity between conditions ( P > 0.05). No differences were observed in steps, MET-hours, or sit-to-stand transitions between conditions ( P > 0.05). NEPA responses were variable among individuals, with approximately half of participants reducing and half increasing NEPA over the 84 h after each exercise condition., Conclusion: NEPA was not reduced after an acute bout of AEx or REx in a sample of inactive adults with overweight or obesity., Competing Interests: The authors report no conflicts of interest. This work was supported by the National Institutes of Health (NIH) grants, such as NIH/National Center for Advancing Translational Sciences under award numbers UL1TR002535, 1UL01TR002538, KL2TR002539, and NIDDK P30DK048520, and NIH/National Institute of Diabetes and Digestive and Kidney Diseases grants T32DK07658 and T32DK007446. This work was also supported by a pilot grant award from the University of Colorado’s Center for Women’s Health Research. This trial was preregistered at ClinicalTrials.gov (NCT03143868). Drs. Melanson and Cornier are supported by resources from Geriatric Research, Education, and the Clinical Center at the Denver VA Medical Center.

Background: Classic nonparametric tests (cNPTs), like Kruskal-Wallis or Mann-Whitney U, are sometimes used to detect differences in central tendency ( i.e. , means or medians). However, when the tests' assumptions are violated, such as in the presence of unequal variance and other forms of heteroscedasticity, they are no longer valid for testing differences in central tendency. Yet, sometimes researchers erroneously use cNPTs to account for heteroscedasticity., Objective: To document the appropriateness of cNPT use in obesity literature, characterize studies that use cNPTs, and evaluate the citation and public sharing patterns of these articles., Methods: We reviewed obesity studies published in 2017 to determine whether the authors used cNPTs: (1) to correct for heteroscedasticity (invalid); (2) when heteroscedasticity was clearly not present (correct); or (3) when it was unclear whether heteroscedasticity was present (unclear). Open science R packages were used to transparently search literature and extract data on how often papers with errors have been cited in academic literature, read in Mendeley, and disseminated in the media., Results: We identified nine studies that used a cNPT in the presence of heteroscedasticity (some because of the mistaken rationale that the test corrected for heteroscedasticity), 25 articles that did not explicitly state whether heteroscedasticity was present when a cNPT was used, and only four articles that appropriately reported that heteroscedasticity was not present when a cNPT was used. Errors were found in observational and interventional studies, in human and rodent studies, and only when studies were unregistered. Studies with errors have been cited 113 times, read in Mendeley 123 times, and disseminated in the media 41 times, by the public, scientists, science communicators, and doctors., Conclusions: Examples of inappropriate use of cNPTs exist in the obesity literature, and those articles perpetuate the errors via various audiences and dissemination platforms., Competing Interests: No competing interests were disclosed., (Copyright: © 2021 Kroeger CM et al.)

Background: Consumption of added sugars (AS) and sugar-sweetened beverages (SSB) may adversely affect adolescents' weight and cardiovascular disease risk. Reliance on self-reported dietary assessment methods is a common research limitation, which could be overcome by dietary intake biomarkers., Aim: The investigation was a proof-of-concept study to evaluate the proposed carbon isotope ratio (δ 13 C) biomarker of AS intake in adolescents, using a controlled feeding design., Methods: Participants ( n = 33, age 15.3 years, 53% female) underwent two seven-day controlled feeding periods in a randomly assigned order. Diets were matched in composition except for AS content (5% or 25% of total energy). Fasting fingerstick blood samples were collected daily during each diet period., Results: Fingerstick δ 13 C values changed from day 1 to 8 by -0.05 ± 0.071‰ on 5% AS, and +0.03 ± 0.083‰ on 25% AS ( p ≤ 0.001). Reliability was demonstrated between day 7 and 8 δ 13 C values on the 5% (ICC = 0.996 , p ≤ 0.001) and 25% (ICC = 0.997, p ≤ 0.001) AS diets., Conclusions: Larger scale investigations are warranted to determine if this technique could be applied to population-level research in order to help assess the effectiveness of interventions aimed at reducing the consumption of AS or SSB intake.