Anthropometric Equations to Predict Visceral Adipose Tissue in European and American Youth.

OBJECTIVE: To investigate whether prediction equations including a limited but selected number of anthropometrics that consider differences in subcutaneous abdominal adipose tissue may improve prediction of the visceral adipose tissue (VAT) in youth. STUDY DESIGN: Anthropometrics and abdominal adipose tissue by MRI were available in 7-18 years old youth with overweight or obesity: 181 White Europeans and 186 White and Black Americans. Multivariable regressions were performed to develop and validate the VAT anthropometric predictive equations in a cross-sectional study. RESULTS: A model with both waist circumference (WaistC) and hip circumference (HipC) (VAT = [1.594 × WaistC] - [0.681 × HipC] + [1.74 × Age] - 48.95) more strongly predicted VAT in girls of White European ethnicity (R2 = 50.8%; standard error of the estimate [SEE] = 13.47 cm2), White American ethnicity (R2 = 41.9%; SEE, 15.63 cm2), and Black American ethnicity (R2 = 25.1%; SEE, 16.34 cm2) (P < .001), than WaistC or BMI. In boys, WaistC was the strongest predictor of VAT; HipC did not significantly improve VAT prediction. CONCLUSIONS: A model including both WaistC and HipC that considers differences in subcutaneous abdominal adipose tissue more accurately predicts VAT in girls and is superior to commonly measured anthropometrics used individually. In boys, other anthropometric measures did not significantly contribute to the prediction of VAT beyond WaistC alone. This demonstrates that selected anthropometric predictive equations for VAT can be an accessible, cost-effective alternative to imaging methods that can be used in both clinics and research.

Associations between elevated kidney and liver biomarker ratios, metabolic syndrome and all-cause and coronary heart disease (CHD) mortality: analysis of the U.S. National Health and Nutrition Examination Survey (NHANES).

BACKGROUND: We examined the relationship between ratios of select biomarkers of kidney and liver function on all-cause and coronary heart disease (CHD) mortality, both in isolation, and in combination with metabolic syndrome (MetS), among adults (20 + years, n = 10,604). METHODS: Data was derived from the U.S. National Health and Nutrition Examination Survey (1999-2016) including public-use linked mortality follow-up files through December 31, 2015. RESULTS: Select biomarker ratios of kidney (UACR or albuminuria and BUN-CR) and liver (AST-ALT and GGT-ALP) function in isolation and in combination with MetS were associated with all-cause and CHD mortality. Compared to individuals with neither elevated biomarker ratios nor MetS (HR = 1.00, referent), increased risk of all-cause mortality was observed in the following groups: MetS with elevated UACR (HR, 95% CI = 2.57, 1.99-3.33), MetS with elevated AST-ALT (HR = 2.22, 1.61-3.07), elevated UACR without MetS (HR = 2.12, 1.65-2.72), and elevated AST-ALT without MetS (HR = 1.71, 1.35-2.18); no other biomarker ratios were associated with all-cause mortality. For cause-specific deaths, elevated risk of CHD mortality was associated with MetS with elevated UACR (HR = 1.67, 1.05-2.67), MetS with elevated AST-ALT (HR = 2.80, 1.62-4.86), and elevated BUN-CR without MetS (HR = 2.12, 1.12-4.04); no other biomarker ratios were associated with CHD mortality. CONCLUSION: Future longitudinal studies are necessary to examine the utility of these biomarker ratios in risk stratification for chronic disease management.

No differences in the body fat after violating core bioelectrical impedance measurement assumptions.

OBJECTIVE: It is unclear to what degree acutely violating bioelectrical impedance analysis (BIA) measurement assumptions will alter the predicted percent fat mass (%FM) and whether this differs by sex or body mass index (BMI). METHODS: %FM was assessed under control, dehydration, exercise, water, food intake and non-voided bladder conditions with three BIA devices (Tanita: BC-418, TBF-314, & Omron HBF-306CN) for men (n = 23, age: 24.0 ± 5.2 years old) and women (n = 17, age: 22.5 ± 3.4 years old) separately. RESULTS: For all BIA devices, there were no differences in the %FM values between the control and the other conditions in men or women (- 1.9 to 0.4%, p > 0.05). Across the three devices and five conditions, 97% of %FM tests returned values within 5% of control (2 tests), and 86% of tests were within 2% of control despite violating an assumption. The errors were greatest with dehydration and women were more likely to have a %FM difference greater than 2% than men with dehydration using the hand-to-foot device (Tanita TBF-314: 59% versus 9%). There were no differences in %FM between control and the conditions when examined by BMI (overweight/obesity: - 2.8 to 0.1% and normal weight: - 1.7 to 0.5%; BMI*trial, p = 0.99). CONCLUSION: %FM estimates were similar despite acutely violating the preliminary measurement BIA assumptions across a range of different BMIs. The minor variations in %FM are smaller than what would be expected with day-to-day variability or weight loss intervention but may be larger in women than men.

Sex and Ethnic Differences in the Relationship between Changes in Anthropometric Measurements and Visceral Fat in Adolescents with Obesity.

OBJECTIVE: To examine sex and ethnic differences in how baseline and changes in anthropometric measures relate with change in visceral fat with interventions in adolescents. STUDY DESIGN: Black and white adolescents (n = 143: body mass index [BMI] ≥85th percentile, 12-18 years) who participated in intervention studies (3-6 months) were included and had assessments of anthropometric measures (weight, BMI, waist circumference, waist-to-hip ratio [WHR], and waist-to-thigh ratio) and visceral fat at L4-L5 by magnetic resonance imaging before and after interventions. RESULTS: At baseline, all of the anthropometric measures were positively associated with visceral fat (P < .05), with weight, waist circumference, and WHR having the largest variance explained (model adjusted R2 = 0.35-0.47 vs 0.32-0.35). Blacks had 11.5-23.3 cm2 less visceral fat compared with whites for a given anthropometric value. Girls tended to have less visceral fat for a given anthropometric value, but the sex differences were not consistently significant (range: 0.7-12.9 cm2). Changes in waist circumference, BMI, and weight, but not WHR, remained significantly associated with changes in visceral fat. There were no sex differences, and much more minimal ethnic differences (<4.9 cm2). CONCLUSIONS: At baseline, there are sex and ethnic differences in how anthropometric measures correlate with visceral fat. However, there were minimal sex and ethnic differences in how changes in anthropometric measures related with changes in visceral fat. Although all of the anthropometric measures were associated with visceral fat at baseline, waist circumference, BMI, and weight, but not WHR were associated with changes in visceral fat. TRIAL REGISTRATION: Clinicaltrials.gov: NCT00739180, NCT01323088, and NCT01938950.

Effects of Exercise Modality on Insulin Resistance and Ectopic Fat in Adolescents with Overweight and Obesity: A Randomized Clinical Trial.

OBJECTIVE: To examine whether a combined aerobic exercise and resistance exercise is more effective than either aerobic exercise or resistance exercise alone in improving insulin sensitivity and reducing total adiposity and ectopic fat in adolescents. STUDY DESIGN: A total of 118 sedentary adolescents with overweight/obesity (body mass index >85th percentile, 12-17 years) were recruited from October 2013 through April 2017 at Children's Hospital of Pittsburgh. Participants were randomized to 1 of the following 6-month exercise groups (3 d/wk, 180 min/wk): aerobic exercise (n = 38), resistance exercise (n = 40), and combined aerobic exercise and resistance exercise (n = 40). The primary outcome was the change in insulin-stimulated glucose disposal by a 3-hour hyperinsulinemic-euglycemic clamp. The secondary outcomes were changes in liver fat by proton magnetic resonance spectroscopy and intermuscular adipose tissue by computed tomography. RESULTS: Of the 118 participants randomized, 85 participants (72%) completed the study with 90% exercise attendance. Total adiposity reduced similarly in all groups (-2%, P < .05). After adjusting for age and sex, insulin-stimulated glucose disposal increased (P < .05) in all groups, with the increase in the aerobic exercise group being greater than the resistance exercise group (1.7 ± 0.1 vs 0.7 ± 0.1 mg/kg/min, P < .05) but not different from the combined group (1.2 ± 0.1 mg/kg/min). Liver fat was reduced (P < .05) in the aerobic exercise (-0.6%) and combined (-0.6%) groups but not in the resistance exercise group (-0.3%, P > .05). Intermuscular adipose tissue decreased (P < .05) similarly in all groups. CONCLUSION: Combined aerobic exercise and resistance exercise and aerobic exercise alone are similarly beneficial in improving insulin sensitivity and reducing ectopic fat in adolescents with obesity. TRIAL REGISTRATION: ClinicalTrials.gov: NCT01938950.

Compulsive "grazing" and addictive tendencies towards food.

Evidence suggests that palatable foods can promote an addictive process akin to drugs of abuse. To date, research in the field of food addiction has focused largely on binge eating as a symptom of this condition. The present study investigated relationships between food addiction and other patterns of overeating, such as compulsive grazing-a behaviour with high relevance to bariatric surgery outcomes. Adults between the ages of 20 and 50 years (n = 232) were recruited for the study. Participants completed questionnaires to assess various eating behaviours and related personality measures. Regression analysis employed the Yale Food Addiction Scale (YFAS) as the dependent variable. Results indicated that addictive personality traits, reward-driven eating, and compulsive grazing each contributed unique variance to the YFAS symptom score. These findings provide novel insight into the association between a grazing pattern of overeating and food addiction, and emphasize that similar to traditional addiction disorders such as alcoholism, binge consumption is not the only pattern of compulsive intake.

Visceral fat is associated with the racial differences in liver fat between black and white adolescent boys with obesity.

OBJECTIVE: We examined whether racial differences in liver fat are associated with the differences in abdominal fat distribution or cardiorespiratory fitness (CRF). METHODS: Participants included 57 black and white obese boys (12-18 years). Total and abdominal fat was measured by dual-energy X-ray absorptiometry (DXA) and magnetic resonance imaging, respectively. CRF was measured using a maximal graded treadmill test with the use of standard open-circuit spirometry techniques until volitional fatigue. Liver fat was measured using a 3T proton magnetic resonance spectroscopy. Fatty liver was defined as having liver fat ≥5%. RESULTS: In the sample, 16.1% of black boys and 30.8% of white boys had fatty liver. Liver fat was associated (P ≤ .05) with body mass index (BMI) percentile (r = 0.28), total fat (r = 0.31), waist circumference (r = 0.38), visceral fat (r = 0.62), abdominal subcutaneous adipose tissue (r = 0.30), and CRF (r = -0.27) adjusting for age and race. White boys had greater liver fat than black boys with adjustment for age and differences in BMI percentile or CRF, but not with waist circumference or visceral fat (P > .05). In a model with age, ethnicity, total body fat, fat-free mass, visceral fat, abdominal subcutaneous fat, and CRF, visceral fat was the only factor to be independently associated with increased odds of having fatty liver (OR = 1.12; 95% CI: 1.04-1.21; P = .003). CONCLUSION: The racial disparities in liver fat between obese black vs white adolescents are explained, in part, by differences in visceral fat.

The readiness and motivation interview for families (RMI-Family) managing pediatric obesity: study protocol.

BACKGROUND: Experts recommend that clinicians assess motivational factors before initiating care for pediatric obesity. Currently, there are no well-established clinical tools available for assessing motivation in youth with obesity or their families. This represents an important gap in knowledge since motivation-related information may shed light on which patients might fail to complete treatment programs. Our study was designed to evaluate the measurement properties and utility of the Readiness and Motivational Interview for Families (RMI-Family), a structured interview that utilizes a motivational interviewing approach to (i) assess motivational factors in youth and their parents, and (ii) examine the degree to which motivation and motivation-related concordance between youth and parents are related to making changes to lifestyle habits for managing obesity in youth. METHODS: From 2016 to 2020, this prospective study will include youth with obesity (body mass index [BMI] ≥97th percentile; 13-17 years old; n = 250) and their parents (n = 250). The study will be conducted at two primary-level, multidisciplinary obesity management clinics based at children's hospitals in Alberta, Canada. Participants will be recruited and enrolled after referral to these clinics, but prior to initiating clinical care. Each youth and their parent will complete the RMI-Family (~1.5 h) at baseline, and 6- and 12-months post-baseline. Individual (i.e., youth or parent) and family-level (i.e., across youth and parent) responses to interview questions will be scored, as will aspects of interview administration (e.g., fidelity to motivational interviewing tenets). The RMI-Family will also be examined for test-retest reliability. Youth data collected at each time point will include demography, anthropometry, lifestyle habits, psychosocial functioning, and health services utilization. Cross-sectional and longitudinal associations between individual and family-level interview scores on the RMI-Family and these clinical measures will be examined. DISCUSSION: As a measurement tool drawing on family-centered care and motivational interviewing, the RMI-Family was designed to increase understanding of the role of motivational factors in pediatric obesity management, allowing healthcare providers and policymakers to manage pediatric obesity more effectively and efficiently. Findings will help to create an innovative, tailored model of health care delivery that uses resources judiciously and is designed to best meet families' needs.

Associations between visceral fat and liver fat with insulin sensitivity and metabolic risk in obese adolescents.

We examined the joint and independent associations between VAT and LF with insulin sensitivity (IS) and lipids in seventy-one obese adolescents (BMI ≥ 95th, 14.9 ± 1.8 years). VAT was assessed by magnetic resonance imaging, and LF was quantified by proton magnetic resonance spectroscopy. IS was evaluated by a 3 -h hyperinsulinemic (80 mU·m(-2)·min(-1)) euglycemic clamp. Independent associations between VAT and LF on metabolic variables were assessed in mutually adjusted multivariate models. The joint association between VAT and LF on metabolic variables was assessed by categorizing participants into a low VAT + low LF group (n = 35), high VAT + low LF group (n = 26), or high VAT + high LF group (n = 10), based on a VAT median split (1.17 kg) and high (≥5%) and low (<5%) LF. Both VAT and LF were independently associated with fasting insulin, 2 h insulin, insulin AUC, IS, and triglycerides (P < 0.05). Adolescents with high VAT + high LF had higher 2 h glucose, glucose AUC, 2 h insulin, triglycerides, and lower insulin sensitivity compared to adolescents with high VAT only (P < 0.025 for all). In obese adolescents, VAT and LF were independently associated with insulin sensitivity and dyslipidemia, and the concomitant presence of VAT and LF is strongly associated with metabolic risk factors.

Differences in physical activity domains, guideline adherence, and weight history between metabolically healthy and metabolically abnormal obese adults: a cross-sectional study.

BACKGROUND: Despite the accepted health consequences of obesity, emerging research suggests that a significant segment of adults with obesity are metabolically healthy (MHO). To date, MHO individuals have been shown to have higher levels of physical activity (PA), but little is known about the importance of PA domains or the influence of weight history compared to their metabolically abnormal (MAO) counterpart. OBJECTIVE: To evaluate the relationship between PA domains, PA guideline adherence, and weight history on MHO. METHODS: Pooled cycles of the National Health and Nutritional Examination Survey (NHANES) 1999-2006 (≥20 y; BMI ≥ 30 kg/m(2); N = 2,753) and harmonized criteria for metabolic syndrome (MetS) were used. Participants were categorized as "inactive" (no reported PA), "somewhat active" (>0 to < 500 metabolic equivalent (MET) min/week), and "active" (PA guideline adherence, ≥ 500 MET min/week) according to each domain of PA (total, recreational, transportation and household). Logistic and multinomial regressions were modelled for MHO and analyses were adjusted for age, sex, education, ethnicity, income, smoking and alcohol intake. RESULTS: Compared to MAO, MHO participants were younger, had lower BMI, and were more likely to be classified as active according to their total and recreational PA level. Based on total PA levels, individuals who were active had a 70% greater likelihood of having the MHO phenotype (OR = 1.70, 95% CI: 1.19-2.43); however, once stratified by age (20-44 y; 45-59 y; and; ≥60 y), the association remained significant only amongst those aged 45-59 y. Although moderate and vigorous PA were inconsistently related to MHO following adjustment for covariates, losing ≥30 kg in the last 10 y and not gaining ≥10 kg since age 25 y were significant predictors of MHO phenotype for all PA domains, even if adherence to the PA guidelines were not met. CONCLUSION: Although PA is associated with MHO, the beneficial effects of PA may be moderated by longer-term changes in weight. Longitudinal analysis of physical activity and weight change trajectories are necessary to isolate the contribution of duration of obesity, PA behaviours, and longer-term outcomes amongst MHO individuals.

Effect of Aerobic versus Resistance Exercise on Pulse Wave Velocity, Intima Media Thickness and Left Ventricular Mass in Obese Adolescents.

A cardiovascular comorbidity in obese adolescents is increased aortic pulse wave velocity (aPWV), carotid intima-media thickness (cIMT) and left ventricular mass (LVM). We investigated in obese adolescents 1) the risk factors associated with aPWV, cIMT and LVM, and 2) the effects of aerobic (AE) versus resistance (RE) exercise alone (without calorie restriction) on aPWV, cIMT, LVM index (LVMI) and cardiometabolic risk factors. Eighty-one obese adolescents (12-18 yrs, BMI ≥95th percentile) were randomized to 3 months of AE (n = 30), RE (n = 27) or a control group (n = 24). Outcome measures included aPWV, cIMT, LVMI, body composition, cardiorespiratory fitness (CRF), blood pressure (BP) and lipids. At baseline, the strongest correlates of aPWV were body weight (r = .31) and diastolic BP (r = .28); of cIMT were body weight (r=0.26) and CRF (r=-0.25); and of LVMI was CRF (r=0.32) after adjusting for sex and race (p < .05 for all). Despite significant reductions in total fat and improvements in CRF in the AE and RE groups, aPWV, cIMT, LVMI, BP, lipids and body weight did not change as compared with controls (p > .05 for all). Interventions of longer duration or together with weight loss may be required to improve these early biomarkers of CVD in obese adolescents.

Estimating Serving Sizes for Healthier and Unhealthier Versions of Food According to Canada's Food Guide.

PURPOSE: Canada's Food Guide (CFG) defines food serving sizes and recommends a specific number of servings from each of the 4 food groups. However, there is no differentiation in serving sizes for different versions of foods that may differ in nutritional value. METHODS: Participants (n = 20) estimated serving sizes of "healthier" and "unhealthier" versions of milk, bread, cereal, potatoes, chicken, fish, and juice and reported the amount normally consumed in 1 sitting. RESULTS: Participants estimated unhealthier servings of cereal and juice to be smaller than healthier servings, but estimated unhealthier servings of chicken to be larger than healthier versions (P < 0.05). There were no differences for bread, milk, potatoes, and fish. Accordingly, estimated servings of juice (P < 0.01) had more calories than the unhealthier orange drink. There were no caloric differences for cereal (P = 0.12), but an estimated serving of bran flakes had more fat and fibre than frosted flakes cereal. CONCLUSIONS: In contrast with CFG, which does not account for different versions of food, certain unhealthier foods were estimated to be smaller or larger than the healthier versions. However, both healthy and unhealthy serving sizes still tended to be larger than what is prescribed in CFG. Thus, better education or revision of serving sizes in future editions of CFG may warrant consideration.

Differences in lumbopelvic control and occupational behaviours in female nurses with and without a recent history of low back pain due to back injury.

Low back pain is highly prevalent in nurses. This study aimed to determine which physical fitness, physical activity (PA) and biomechanical characteristics most clearly distinguish between nurses with [recently injured (RInj)] and without [not recently injured (NRInj)] a recent back injury. Twenty-seven (8 RInj, 19 NRInj) female nurses completed questionnaires (pain, work, PA), physical fitness, biomechanical and low back discomfort measures, and wore an accelerometer for one work shift. Relative to NRInj nurses, RInj nurses exhibited reduced lumbopelvic control (41.4% more displayed a moderate loss of frontal plane position), less active occupational behaviours (less moderate PA; less patient lifts performed alone; more sitting and less standing time) and more than two times higher low back discomfort scores. Despite no physical fitness differences, the lumbopelvic control, occupational behaviours and discomfort measures differed between nurses with and without recent back injuries. It is unclear whether poor lumbopelvic control is causal or adaptive in RInj nurses and may require further investigation. Practitioner Summary: It is unclear which personal modifiable factors are most clearly associated with low back pain in nurses. Lumbopelvic control was the only performance-based measure to distinguish between nurses with and without recent back injuries. Future research may investigate whether reduced lumbopelvic control is causal or adaptive in recently injured nurses.

Effectiveness of a publicly funded clinical paediatric weight management program on obesity outcomes.

OBJECTIVE: To determine the effectiveness of a publicly funded, paediatric weight management clinic in decreasing obesity. METHODS: A retrospective chart review of patients four to 16 years of age, from 2006 to 2009, was performed at a medically supervised weight management clinic (n=121). Patients participated in monthly visits and were educated about the cognitive behavioural and nutritional aspects of weight management. RESULTS: The sample included 51 male and 70 female patients with a mean (± SD) initial age of 11.7±3.0 years. Patients participated in 6.4±6.5 visits (range one to 31 visits) over 13.7±15.5 months and 7.4% of patients discontinued treatment after their initial visit. Of the patients who attended the clinic >1 time, 66.1% attended for at least four months, 48.2% attended for >8 months and 33.0% attended for >1 year. Over the course of their treatment, patients experienced a weight gain of 3.8±9.5 kg, but a reduction in body mass index (BMI) percentile (-1.1±3.6%). Post-treatment, the prevalence of obesity decreased from 96.7% to 87.5%. Patients with longer treatment times (>12 months) attained significantly lower final BMI percentiles than patients with shorter treatment times; however, there was no difference in the rate of reduction. Initial treatment age, sex and medical conditions were not related to BMI percentile change. CONCLUSIONS: This paediatric weight management program effectively reduced the prevalence of obesity. Patients who had longer treatment times experienced greater reductions in obesity. Overall, the present study highlights that long-term patient attendance may be needed to better support paediatric weight management patients.

OBJECTIF: Déterminer l'efficacité d'une clinique pédiatrique publique de gestion du poids pour réduire l'obésité. MÉTHODOLOGIE: Les chercheurs ont effectué une analyse rétrospective des dossiers des patients de quatre à 16 ans dans une clinique de gestion du poids supervisée par des médecins (n=121), de 2006 à 2009. Les patients allaient à des rendezvous mensuels et recevaient de l'information sur les aspects cognitivo-comportementaux et nutritionnels de la gestion du poids. RÉSULTATS: L'échantillon était composé de 51 patients et de 70 patientes d'un âge initial moyen (± ÉT) de 11,7±3,0 ans. Les patients ont assisté à 6,4±6,5 rendezvous (plage de un à 31) répartis sur 13,7±15,5 mois, et 7,4 % d'entre eux ont mis un terme au traitement après leur premier rendezvous. Chez les patients qui avaient fréquenté la clinique plus d'une fois, 66,1 % l'avaient fait pendant au moins quatre mois, 48,2 %, plus de huit mois et 33,0 %, plus d'un an. Pendant la durée de leur traitement, les patients ont pris 3,8±9,5 kg, mais ont réduit leur percentile d'indice de masse corporelle (IMC, −1,1±3,6 %). Après le traitement, la prévalence d'obésité diminuait de 96,7 % à 87,5 %. Les patients traités plus longtemps (plus de 12 mois) obtenaient un percentile d'IMC final considérablement plus faible que ceux traités moins longtemps, mais on ne constatait pas de différence dans le taux de perte de poids. L'âge, le sexe et l'état de santé au début du traitement n'étaient pas liés au changement de percentile d'IMC. CONCLUSIONS: Ce programme pédiatrique de gestion du poids assurait une réduction efficace de la prévalence d'obésité. Les patients qui étaient traités plus longtemps devenaient moins obèses. Dans l'ensemble, la présente étude démontre qu'une participation plus longue au programme s'impose peut-être pour mieux soutenir la gestion du poids des patients d'âge pédiatrique.

Aerobic exercise but not resistance exercise reduces intrahepatic lipid content and visceral fat and improves insulin sensitivity in obese adolescent girls: a randomized controlled trial.

It is unclear whether regular exercise alone (no caloric restriction) is a useful strategy to reduce adiposity and obesity-related metabolic risk factors in obese girls. We examined the effects of aerobic (AE) vs. resistance exercise (RE) alone on visceral adipose tissue (VAT), intrahepatic lipid, and insulin sensitivity in obese girls. Forty-four obese adolescent girls (BMI ≥95th percentile, 12-18 yr) with abdominal obesity (waist circumference 106.5 ± 11.1 cm) were randomized to 3 mo of 180 min/wk AE (n = 16) or RE (n = 16) or a nonexercising control group (n = 12). Total fat and VAT were assessed by MRI and intrahepatic lipid by proton magnetic resonance spectroscopy. Intermuscular AT (IMAT) was measured by CT. Insulin sensitivity was evaluated by a 3-h hyperinsulinemic (80 mU·m(2)·min(-1)) euglycemic clamp. Compared with controls (0.13 ± 1.10 kg), body weight did not change (P > 0.1) in the AE (-1.31 ± 1.43 kg) and RE (-0.31 ± 1.38 kg) groups. Despite the absence of weight loss, total body fat (%) and IMAT decreased (P < 0.05) in both exercise groups compared with control. Compared with control, significant (P < 0.05) reductions in VAT (Δ-15.68 ± 7.64 cm(2)) and intrahepatic lipid (Δ-1.70 ± 0.74%) and improvement in insulin sensitivity (Δ0.92 ± 0.27 mg·kg(-1)·min(-1) per µU/ml) were observed in the AE group but not the RE group. Improvements in insulin sensitivity in the AE group were associated with the reductions in total AT mass (r = -0.65, P = 0.02). In obese adolescent girls, AE but not RE is effective in reducing liver fat and visceral adiposity and improving insulin sensitivity independent of weight loss or calorie restriction.

Changes in the prevalence of U.S. adults using diet, exercise, pharmaceuticals and diet products for weight loss over time: Analysis of NHANES 1999-2018.

To examine changes in the use of diet, exercise, and pharmacological/diet product weight loss (WL) practices over time, and differences in these trends by sex and obesity status, data from the National Health and Examination Survey (NHANES Continuous 1999-2018) was used. The prevalence of diet, exercise and use of WL drugs and products over time were examined in men and women with and without obesity in a series of cross-sectional nationally representative samples (n = 43,020). Women and those with obesity were more likely to engage in WL practices over the past year, with an increased prevalence of WL efforts over time (38.4 to 43.2%). Amongst those who engaged in WL attempts, diet-related WL was most common (87-93%), followed by exercise-related WL (47-68%), whereas use of WL drugs and products was the least common (5-21%). There were modest differences in the prevalence of diet or exercise WL over time, with some differences by sex and obesity status. Most notable was the increase in the prevalence of exercise WL practices in women with obesity, with no differences among men or women without obesity. When examining specific types of diets, there were more clear differences in the adoption of diets over time, with the use of more traditional calorie/portion/fat restriction diets becoming less prevalent, and sugar/carbohydrate restriction becoming more prevalent over time (P<0.005). Changes over time in the use of diets were, were however, similar in men and women with and without obesity. Use of pharmacotherapy/diet products tended to decline in prevalence over time but was consistently highest in women with obesity. Thus, there are differences in the types of WL strategies individuals have employed over time, with variations in their popularity of use by sex and obesity status. However, the pattern of changes over time were quite similar in men and women with and without obesity.

Is anyone truly healthy? Trends in health risk factors prevalence and changes in their associations with all-cause mortality.

OBJECTIVE: The purpose of the study was to determine trends in the prevalence of individual health risk factors across time and to examine if their associations with mortality have changed over time. METHODS: Data from the National Health and Nutrition Examination Surveys (NHANES III- 1988-1994 and NHANES 1999-2014; age ≥20 years) was used to examine differences in the odds ratio (OR) of 5-year mortality risk associated with various common health risk factors over the two survey periods using weighted logistic regression analysis adjusting for age, sex, obesity category and white ethnicity (n = 28,279). RESULTS: Over 97% of individuals had at least one of the 19 risk factors examined with no difference in the prevalence over time (P>0.34). The prevalence of lifestyle, social/mental and physical risk factors (2.2 to 19.1%) increased over time (P<0.0002), while the prevalence of having physiological risk factors decreased by ~6.5% (P<0.0001). Having any lifestyle or social/mental risk factor was significantly associated with a higher 5-year OR for mortality risk in 1999-2014, than 1988-94. In particular, having low education or use of mental health medication were not associated with mortality risk in 1988-94 (P>0.1), but were significantly associated with a higher 5-year OR for mortality in 1999-2014 (P<0.0001). Conversely, physiological risk factors were more weakly related with mortality risk in 1988-1994, than 1999-2014. Having any physical risk factor, and poor self-rated health were similarly related with 5-year mortality risk at both timepoints. CONCLUSION: Health risk factors have both increased and decreased in prevalence over time, along with changes in the association between many of the risk factors and mortality risk. Taken together, these changes complicate interpretation of temporal trends and warrant cautious interpretation of population health patterns based on surveillance data.

Effect of Short Bouts of Vigorous Stair Climbing on Cardiorespiratory Fitness in Women with Overweight and Obesity: A Pilot Feasibility Study.

Background: We examined the effect of 4 weeks of a brief vigorous stair climbing exercise on cardiorespiratory fitness (CRF) and body composition in women with overweight or obesity. Methods: Twenty-six participants (age, 25.4±4.9 years; body mass index [BMI], 25.3±1.8 kg/m2) were randomly assigned to either a stair climbing exercise group (n=13) or a non-exercising control group (n=13). The stair climbing exercise group performed 20 sessions (supervised, five sessions/week over 4 weeks) of brief intermittent stair climbing exercise consisting of a 3-minute warm-up followed by three bouts of 20 seconds of stair climbing (≥80% of age-predicted maximum heart rate) interspersed with 2-minute recovery periods (total exercise duration=10 minutes/session). Peak oxygen uptake (VO2peak) was measured using a graded maximal treadmill test with the use of a standard open-circuit spirometry technique. Body composition was assessed with bioelectrical impedance analysis. Results: All participants, except one who dropped out due to coronavirus disease 2019 (COVID-19) infection, completed the study with 100% attendance rates. There were significant interaction effects (group×time) on body weight, BMI, waist circumference, and CRF such that the stair climbing exercise group had significant (P≤0.01) reductions in body weight (66.5±4.6 to 65.2±4.6 kg), BMI (24.8±1.2 to 24.4±1.1 kg/m2), and waist circumference (78.0±3.7 to 76.5±4.1 cm) and improvements in VO2peak (31.6±2.5 to 34.9±2.6 mL/kg/min) compared with controls. Conclusion: Short bouts of vigorous stair climbing is a feasible and time-efficient exercise strategy for improving CRF in previously sedentary, young women with overweight and obesity.