BUSCADOR RECOLECTA

Background: There is a subset of individuals with overweight/obesity characterized by a lower risk of cardiometabolic complications, the so-called metabolically healthy overweight/obesity (MHOO) phenotype. Despite the relatively higher levels of subcutaneous adipose tissue and lower visceral adipose tissue observed in individuals with MHOO than individuals with metabolically unhealthy overweight/obesity (MUOO), little is known about the differences in brown adipose tissue (BAT). Methods: This study included 53 young adults (28 women) with a body mass index (BMI) ¿25 kg/m2 which were classified as MHOO (n = 34) or MUOO (n = 19). BAT was assessed through a static 18F-FDG positron emission tomography/computed tomography scan after a 2-h personalized cooling protocol. Energy expenditure, skin temperature, and thermal perception were assessed during a standardized mixed meal test (3.5 h) and a 1-h personalized cold exposure. Body composition was assessed by dual-energy x-ray absorptiometry, energy intake was determined during an ad libitum meal test and dietary recalls, and physical activity levels were determined by a wrist-worn accelerometer. Findings: Participants with MHOO presented higher BAT volume (+124%, P = 0.008), SUVmean (+63%, P = 0.001), and SUVpeak (+133%, P = 0.003) than MUOO, despite having similar BAT mean radiodensity (P = 0.354). In addition, individuals with MHOO exhibited marginally higher meal-induced thermogenesis (P = 0.096) and cold-induced thermogenesis (+158%, P = 0.050). Moreover, MHOO participants showed higher supraclavicular skin temperature than MUOO during the first hour of the postprandial period and during the cold exposure, while no statistically significant differences were observed in other skin temperature parameters. We observed no statistically significant differences between MHOO and MUOO in thermal perception, body composition, outdoor ambient temperature exposure, resting metabolic rate, energy intake, or physical activity levels. Interpretation: Adults with MHOO present higher BAT volume and activity than MUOO. The higher meal- and cold-induced thermogenesis and cold-induced supraclavicular skin temperature are compatible with a higher BAT activity. Overall, these results suggest that BAT presence and activity might be linked to a healthier phenotype in young adults with overweight or obesity., The study was supported by the Junta de Andalucía, Consejería de Transformación Económica, Industria, Conocimiento y Universidades Dirección General de Investigación y Transferencia del Conocimiento (ref. P18-RT-4455, ref. SOMM17/6107/UGR, and DOC 01151) and European Regional Development Funds (ERDF), the Spanish Ministry of Economy and Competitiveness via the Fondo de Investigación Sanitaria del Instituto de Salud Carlos III (PI13/01393), and PTA-12264, Retos de la Sociedad (DEP2016-79512-R), the Spanish Ministry of Education (FPU13/04365, FPU15/04059 and FPU19/01609), the Fundación Iberoamericana de Nutrición (FINUT), the Redes Temáticas de Investigación Cooperativa RETIC (Red SAMID RD16/0022), the AstraZeneca HealthCare Foundation, the University of Granada Plan Propio de Investigación 2016 -Excellence actions: Unit of Excellence on Exercise and Health (UCEES). G.SD is supported by a Marie Sklodowska-Curie Actions-Individual Fellowship (101028941; Horizon 2020, European Commission). B.MT is supported by a grant for the requalification of the Spanish university system from the Ministry of Universities of the Government of Spain, funded by the European Union, NextGeneration EU (María Zambrano program, reference RR _C_2021_04). J.M.A.A. is supported by the Juan de la Cierva-Formación Grant FJC2020-044453-I funded by MCIN/AEI/10.13039/501100011033 and 'European Union NextGeneration EU/PRTR'

Purpose: To investigate the association of meal timing with body composition and cardiometabolic risk factors in young adults.
Methods: In this cross-sectional study participated 118 young adults (82 women; 22±2 years old; BMI: 25.1±4.6 kg/m2). Meal timing was determined via three non-consecutive 24-h dietary recalls. Sleep outcomes were objectively assessed using accelerometry. The eating window (time between frst and last caloric intake), caloric midpoint (local time at which≥50% of daily calories are consumed), eating jetlag (variability of the eating midpoint between non-working and working days), time from the midsleep point to frst food intake, and time from last food intake to midsleep point were calculated. Body composition was determined by DXA. Blood pressure and fasting cardiometabolic risk factors (i.e., triglycerides, total cholesterol, high-density lipoprotein-cholesterol, low-density lipoprotein-cholesterol, and insulin resistance) were measured.
Results: Meal timing was not associated with body composition (p>0.05). The eating window was negatively related to HOMA-IR and cardiometabolic risk score in men (R2=0.348, β=−0.605; R2=0.234, β=−0.508; all p≤0.003). The time from midsleep point to frst food intake was positively related to HOMA-IR and cardiometabolic risk score in men (R2=0.212, β=0.485; R2=0.228, β=0.502; all p=0.003). These associations remained after adjusting for confounders and multiplicity (all p≤0.011).
Conclusions: Meal timing seems unrelated to body composition in young adults. However, a longer daily eating window and a shorter time from midsleep point to frst food intake (i.e., earlier frst food intake in a 24 h cycle) are associated with better cardiometabolic health in young men.
Clinical trial registration: NCT02365129 (https://www.clinicaltrials.gov/ct2/show/NCT02365129?term=ACTIBATE&draw= 2&rank=1)., Funding for open access publishing: Universidad de Granada/CBUA. This study was funded by the Spanish Ministry of Economy and Competitiveness via the Fondo de Investigación Sanitaria del Instituto de Salud Carlos III (PI13/01393) and PTA 12264-I, by Retos de la Sociedad (DEP2016-79512-R), European Regional Development Funds (ERDF), Spanish Ministry of Universities (FPU 13/03410, FPU14/04172 and FPU18/03357), the Fundación Iberoamericana de Nutrición (FINUT), the Redes Temáticas de Investigación Cooperativa RETIC network (Red SAMID RD16/0022), the AstraZeneca HealthCare Foundation, Junta de Andalucía, Consejería de Transformación económica, Industria, Conocimiento y Universidades (A-CTS-516-UGR20), the University of Granada's Plan Propio de Investigación 2016—Excellence actions: Unit of Excellence on Exercise and Health (UCEES), the Junta de Andalucía, Consejería de Conocimiento, Investigación y Universidades (ERDF, SOMM17/6107/UGR), and a postdoctoral grant from the Fundación Alfonso Martín Escudero.

Aim:
Previous evidence suggest that a sexual dimorphism in exercise fat oxidation and adipokines levels may explain a lower risk of cardio-metabolic disorders in women. Therefore, we investigated the role of sex in the relationship between adipokines levels, maximal fat oxidation (MFO) during exercise and insulin resistance.

Methods:
Fifty young adults with excess adiposity (31 women; body fat: 38.7 ± 5.3%) were included in this study. The fasting levels of leptin, adiponectin, glucose and insulin were determined from blood samples and the homeostatic model assessment of insulin resistance index (HOMA-IR) subsequently calculated. Body fat percentage and visceral adipose tissue (VAT) were assessed through dual-energy X-ray absorptiometry whereas MFO was estimated during an incremental-load exercise test after an overnight fasting through indirect calorimetry.

Results:
Men had lower levels of body fat (d = 1.80), adiponectin (d = 1.35), leptin (d = 0.43) and MFO (d = 1.25) than women. Conversely, men showed higher VAT (d = 0.85) and fasting glucose levels (d = 0.89). No sex differences were observed in HOMA-IR (d = 0.34). Adipokines levels were not associated with MFO in both sexes (r < 0.30), whereas adiponectin levels were inversely related with HOMA-IR in both men (r = −0.58) and women (r = −0.50). Leptin concentration was associated to HOMA-IR only in men (r = 0.41), while no statistically significant relationships were observed between MFO and HOMA-IR in both sexes (r < 0.44).

Conclusion:
Insulin resistance was similar between sexes regardless of superior levels of adipokines and MFO during exercise in women. Therefore, adiponectin and leptin may regulate glucose homeostasis without altering whole body fat oxidation rate during exercise., This study was funded by the Spanish Ministry of Economy and Competitiveness via the Fondo de Investigación Sanitaria del Instituto de Salud Carlos III (PI13/01393; J.R.R.) and PTA-12264I, Retos de la Sociedad (DEP2016-79512-R; J.R.R.) and European Regional Development Funds (ERDF; J.R.R.), the Spanish Ministry of Education (FPU13/04365 (G.S.D), FPU14/04172 (F.A.G.) and FPU15/04059 (J.M.A.)), FJOP is supported by the Margarita Salas postdoctoral research contract programm (Ministry of Universities of Spain, European Union - NextGenerationEU) the Fundación Iberoamericana de Nutrición (FINUT; JRR), the Redes Temáticas de Investigación Cooperativa RETIC (Red SAMID RD16/0022; J.R.R.), the AstraZeneca HealthCare Foundation (J.R.R.), the University of Granada Plan Propio de Investigación 2016 -Excellence actions: Unit of Excellence on Exercise, Nutrition and Health (UCEENS) (J.R.R.), the Junta de Andalucía, Consejería de Conocimiento, Investigación y Universidades (ERDF; ref. SOMM17/6107/UGR; JRR), the Junta de Andalucía, Consejería de Economía, Conocimiento, Empresas y Universidad (ref. P18-RT-4455; J.R.R.) and by the CIBEROBN, Centro de Investigación Biomédica en Red (CB22/03/00058), Instituto de Salud Carlos III, Ministerio de Ciencia e Innovación and Unión Europea – European Regional Development Fund (J.R.R.).

Objective This study aimed to describe the energy expenditure (EE) and macronutrient oxidation response to an individualized nonshivering cold exposure in young healthy adults. Methods Two different groups of 44 (study 1: 22.1 [SD 2.1] years old, 25.6 [SD 5.2] kg/m(2), 34% men) and 13 young healthy adults (study 2: 25.6 [SD 3.0] years old, 23.6 [SD 2.4] kg/m(2), 54% men) participated in this study. Resting metabolic rate (RMR) and macronutrient oxidation rates were measured by indirect calorimetry under fasting conditions in a warm environment (for 30 minutes) and in mild cold conditions (for 65 minutes, with the individual wearing a water-perfused cooling vest set at an individualized temperature adjusted to the individual's shivering threshold). Results In study 1, EE increased in the initial stage of cold exposure and remained stable for the whole cold exposure (P < 0.001). Mean cold-induced thermogenesis (9.56 +/- 7.9 kcal/h) was 13.9% +/- 11.6% of the RMR (range: -14.8% to 39.9% of the RMR). Carbohydrate oxidation decreased during the first 30 minutes of the cold exposure and later recovered up to the baseline values (P < 0.01) in parallel to opposite changes in fat oxidation (P < 0.01). Results were replicated in study 2. Conclusions A 1-hour mild cold exposure individually adjusted to elicit maximum nonshivering thermogenesis induces a very modest increase in EE and a shift of macronutrient oxidation that may underlie a shift in thermogenic tissue activity., This study was supported by the Spanish Ministry of Economy and Competitiveness via the Fondo de Investigacion Sanitaria del Instituto de Salud Carlos III (PI13/01393 and PTA 12264-I); the Retos de la Sociedad (DEP2016-79512-R) and European Regional Development Funds (ERDF); the Spanish Ministry of Education (FPU13/04365, FPU14/04172, and FPU15/04059); the Fundacion Iberoamericana de Nutricion; the Redes Tematicas de Investigacion Cooperativa (RETIC, red de Salud Materno Infantil y del Desarrollo 16/0022); the AstraZeneca HealthCare Foundation; the University of Granada Plan Propio de Investigación 2016 excellence actions (Unit of Excellence on Exercise and Health and Plan Propio de Investigacion 2018: Programa Contratos-Puente and Programa Perfeccionamiento de Doctores); the Junta de Andalucía, Consejeria de Conocimiento, Investigación y Universidades (ERDF; SOMM17/6107/UGR); and the Fundación Alfonso Maríin Escudero.

Concurrent training has been postulated as an appropriate time-efficient strategy to improve physical fitness, yet whether the exercise-induced adaptations are similar in men and women is unknown. An unblinded randomized controlled trial was conducted to investigate sex-specific dose–response effects of a 24-week supervised concurrent exercise training program on cardiorespiratory fitness and muscular strength in young adults. One hundred and forty-four sedentary adults aged 18–25 years were assigned to either (i) a control group (n = 54), (ii) a moderate intensity exercise group (MOD-EX, n = 46), or (iii) a vigorous intensity exercise group (VIG-EX, n = 44) by unrestricted randomization. Cardiorespiratory fitness (VO2max), hand grip strength, and one-repetition maximum of leg press and bench press were evaluated at baseline and after the intervention. A total of 102 participants finished the intervention (Control, n = 36; 52% women, MOD-EX, n = 37; 70% women, and VIG-EX, n = 36; 72% women). In men, VO2max significantly increased in the MOD-EX (~8%) compared with the control group and in the VIG-EX group after the intervention (~6.5%). In women, VO2max increased in the MOD-EX and VIG-EX groups (~5.5%) compared with the control group after the intervention. There was a significant increment of leg press in the MOD-EX (~15.5%) and VIG-EX (~18%) groups compared with the control group (~1%) in women. A 24-week supervised concurrent exercise was effective at improving cardiorespiratory fitness and lower body limbs muscular strength in young women—independently of the predetermined intensity—while only at moderate intensity improved cardiorespiratory fitness in men., The study is supported by the Spanish Ministry of Economy and Competitiveness, Fondo de Investigación Sanitaria del Instituto de Salud Carlos III (PI13/01393), Fondos Estructurales de la Unión Europea (FEDER), by the Spanish Ministry of Science and Innovation (RYC-2010-05957, RYC-2011-09011, FJC2020-043385-I), by the Spanish Ministry of Education (FPU 13/04365, and Beca de Colaboración Ref. 11727189), by the University of Granada (Beca de Iniciación a la Investigación), by the Fundación Iberoamericana de Nutrición (FINUT), by the Redes Temáticas de Investigación Cooperativa RETIC (Red SAMID RD12/0026/0015), by AstraZeneca HealthCare Foundation, and by Vegenat®.

Incluye material complementario, Regular physical activity (PA) is an important part of the treatment of several medical conditions, including overweight and obesity, in which there may be a weakened appetite control. Eating behaviour traits influence weight control and may be different in active and sedentary subjects. This paper reports the relationships between the time spent in sedentary behaviour and physical activity (PA) of different intensity, and eating behaviour traits in young, healthy adults. Additionally, it reports the results of a six-month-long, randomized, controlled trial to examine the effect of an exercise intervention on eating behaviour traits. A total of 139 young (22.06 ± 2.26 years) healthy adults (68.35% women) with a Body Mass Index (BMI) of 24.95 ± 4.57 kg/m2 were enrolled. Baseline assessments of habitual PA were made using wrist-worn triaxial accelerometers; eating behaviour traits were examined via the self-reported questionnaires: Binge Eating, Three-Factor Eating Questionnaire-R18 and Control of Eating Questionnaire. The subjects were then randomly assigned to one of three groups: control (usual lifestyle), moderate-intensity exercise (aerobic and resistance training 3¨C4 days/week at a heart rate equivalent to 60% of the heart rate reserve (HRres) for the aerobic component, and at 50% of the 1 repetition maximum (RM) for the resistance component), or vigorous-intensity exercise (the same training but at 80% HRres for half of the aerobic training, and 70% RM for the resistance training). At baseline, sedentary behaviour was inversely associated with binge eating (r = −0.181, p &lt; 0.05) and with uncontrolled eating (r = −0.286, p = 0.001). Moderate PA (MPA) was inversely associated with craving control (r = −0.188, p &lt;0.05). Moderate-to-vigorous PA (MVPA) was directly associated with binge eating (r = 0.302, p &lt; 0.001) and uncontrolled eating (r = 0.346, p &lt; 0.001), and inversely associated with craving control (r = −0.170, p &lt; 0.015). Overall, PA was directly associated with binge eating (r = 0.275, p = 0.001), uncontrolled eating (r = 0.321, p &lt; 0.001) and emotional eating (r = 0.204, p &lt; 0.05). Additionally, only emotional eating was modified by the intervention, increasing in the vigorous-intensity exercise group (p &lt; 0.05). In summary, we observed that time spent in sedentary behaviour/PA of different intensity is associated with eating behaviour traits, especially binge eating in young adults. In contrast, the six-month exercise intervention did not lead to appreciable changes in eating behaviour traits., Funding for this work came from the Spanish Ministry of Economy and Competitiveness via the Fondo de Investigación Sanitaria del Instituto de Salud Carlos III (PI13/01393) and PTA 12264-I, Retos de la Sociedad (DEP2016-79512-R) and European Regional Development Fund (ERDF), the Spanish Ministry of Education (FPU 13/04365 and FPU19/01609), the Fundación Iberoamericana de Nutrición (FINUT), the Redes Temáticas de Investigación Cooperativa (RETIC) (Red SAMID RD16/0022), the AstraZeneca HealthCare Foundation, the University of Granada Research and Knowledge Transfer Fund (PPIT) 2016 Excellence Actions Programme: Scientific Unit of Excellence on Exercise and Health (UCEES) and the Research and Knowledge Transfer Fund (PPIT) 2018 Bridging Contracts Programme and the Andalusian Regional Government, Regional Ministry of Economy, Knowledge, Enterprises and University (ERDF, SOMM17/6107/UGR). Also, international doctoral studies scholarship no. 440575 from the Mexican National Council of Science and Technology (CONACYT).

Exercise modulates both brown adipose tissue (BAT) metabolism and white
adipose tissue (WAT) browning in murine models. Whether this is true in
humans, however, has remained unknown. An unblinded randomized controlled trial (ClinicalTrials.gov ID: NCT02365129) was therefore conducted to
study the effects of a 24-week supervised exercise intervention, combining
endurance and resistance training, on BAT volume and activity (primary outcome). The study was carried out in the Sport and Health University Research
Institute and the Virgen de las Nieves University Hospital of the University of
Granada (Spain). One hundred and forty-five young sedentary adults were
assigned to either (i) a control group (no exercise, n = 54), (ii) a moderate
intensity exercise group (MOD-EX, n = 48), or (iii) a vigorous intensity exercise
group (VIG-EX n = 43) by unrestricted randomization. No relevant adverse
events were recorded. 97 participants (34 men, 63 women) were included in
the final analysis (Control; n = 35, MOD-EX; n = 31, and VIG-EX; n = 31). We
observed no changes in BAT volume (Δ Control: −22.2 ± 52.6 ml; Δ MOD-EX:
−15.5 ± 62.1 ml, Δ VIG-EX: −6.8 ± 66.4 ml; P = 0.771) or 18F-fluorodeoxyglucose
uptake (SUVpeak Δ Control: −2.6 ± 3.1 ml; Δ MOD-EX: −1.2 ± 4.8, Δ VIG-EX:
−2.2 ± 5.1; p = 0.476) in either the control or the exercise groups. Thus, we did
not find any evidence of an exercise-induced change on BAT volume or activity
in young sedentary adults., This study was funded by the Spanish Ministry of Economy and Competitiveness via the Fondo de Investigación Sanitaria del Instituto de Salud Carlos III (PI13/01393; J.R.R.) and PTA-12264I, Retos de la Sociedad (DEP2016-79512-R; J.R.R.) and European Regional Development Funds (ERDF; J.R.R.), the Spanish Ministry of Education (FPU13/04365 (G.S.D.), FPU14/04172 (F.A.G.), FPU15/04059 (J.M.A.), FPU16/03653 (A.M.G.), FPU16/02828 (F.J.O.P.), FPU16/05159 (H.X.), FPU17/01523 (L.O.A.), FPU19/01609 (L.J.F.)), International Doctoral Studies Scholarship no. 440575 from the Mexican National Council of Science and Technology (CONACYT; WDMA), the Fundación Iberoamericana de Nutrición (FINUT; JRR), the Redes Temáticas de Investigación Cooperativa RETIC (Red SAMID RD16/0022; J.R.R.), the AstraZeneca HealthCare Foundation (J.R.R.), the University of Granada Plan Propio de Investigación 2016 -Excellence actions: Unit of Excellence on Exercise and Health (UCEES) (J.R.R.)- and Plan Propio de Investigación 2018 - Programa Contratos-Puente and Programa Perfecionamiento de Doctores (G.S.D.), the Junta de Andalucía, Consejería de Conocimiento, Investigación y Universidades (ERDF; ref. SOMM17/6107/UGR; JRR), the Junta de Andalucía, Consejería de Economía, Conocimiento, Empresas y Universidad (ref. P18-RT-4455; J.R.R.), the Fundación Alfonso Martín Escudero (B.M.T. and G.S.D.), the Maria Zambrano fellowship by the Ministerio de Universidades y la Unión Europea NextGenerationEU (RR_C_2021_04; B.M.T.), and the Novo Nordisk Foundation (NNF18OC0032394; M.S.).

Objective: Brown adipose tissue (BAT) is a thermogenic tissue with potential as a therapeutic target in the treatment of obesity and related metabolic disorders. The most used technique for quantifying human BAT activity is the measurement of 18 F-fluorodeoxyglucose uptake via a positron emission tomography/computed tomography scan following exposure to cold. However, several studies have indicated the measurement of the supraclavicular skin temperature (SST) by infrared thermography (IRT) to be a less invasive alternative. This work reviews the state of the art of this latter method as a means of determining BAT activity in humans.

Methods: The data sources for this review were PubMed, Web of Science, and EBSCOhost (SPORTdiscus), and eligible studies were those conducted in humans.

Results: In most studies in which participants were first cooled, an increase in IRT-measured SST was noted. However, only 5 of 24 such studies also involved a nuclear technique that confirmed increased activity in BAT, and only 2 took into account the thickness of the fat layer when measuring SST by IRT.

Conclusions: More work is needed to understand the involvement of tissues other than BAT in determining IRT-measured SST; at present, IRT cannot determine whether any increase in SST is due to increased BAT activity.

Where people live and work together it is not always possible to modify the ambient temperature; ways must therefore be found that allow individuals to feel thermally comfortable in such settings. The Embr Wave (R) is a wrist-worn device marketed as a 'personal thermostat' that can apply a local cooling stimulus to the skin. The aim of the present study was to determine the effect of an intermittent mild cold stimulus of 25 degrees C for 15-20 s every 5 min over 3.5 days under free-living conditions on 1) skin temperature, 2) perception of skin temperature, 3) sleep quality and 4) resting energy expenditure (REE) in young, healthy adults. Ten subjects wore the device for 3.5 consecutive days. This intervention reduced distal skin temperature after correcting for personal ambient temperature (P < 0.05), but did not affect the subjects' the perception of skin temperature, sleep quality or REE (all P >= 0.051). Thus, this intermittent mild cold regime can reduce distal skin temperature, and wearing it under free-living conditions for 3.5 days does not seem to impair the perception of skin temperature and sleep quality or modify REE., The study was funded by the Spanish Ministry of Economy and Competitiveness via the Fondo de Investigacion Sanitaria del Instituto de Salud Carlos III (PI13/01393 and CB16/10/00239) and PTA 12264-I, Retos de la Sociedad (DEP2016-79512-R), and European Regional Development Funds (ERDF). Other funders included the Spanish Ministry of Education (FPU 16/05159, 15/04059 and 19/02326), the Fundacion Iberoamericana de Nutricion (FINUT), the Redes Tematicas De Investigacion Cooperativa RETIC (Red SAMID RD16/0022), the AstraZeneca Health Care Foundation, the University of Granada Plan Propio de Investigacion 2016 (Excellence actions: Unit of Excellence on Exercise, Nutrition and Health [UCEENS]), and by the Junta de Andalucia, Consejeria de Conocimiento, Investigacion y Universidades (ERDF, SOMM17/6107/UGR). AMT was supported by Seneca Foundation through grant 19899/GERM/15 and the Ministry of Science Innovation and Universities RTI2018-093528-B-I0, as well as DJP (MINECO; RYC-2014-16938). BMT was supported by an individual postdoctoral grant from the Fundacion Alfonso Martin Escudero. We thank Dr. Matt Smith of Embr Labs Inc. for configuring the Embr Wave (R) devices used in this experiment.