Thermal resting pattern and acute skin temperature response to exercise in older adults: Role of cardiorespiratory fitness

Background Infrared thermography is a growing area of interest in sports science due to the potential of skin temperature (Tsk) measurements to provide valuable information from rest to exercise. However, limited research exists on Tsk in older adults and the impact of factors such as sex and cardiorespiratory fitness (CRF) on Tsk. This study aims to investigate Tsk at rest and after acute exercise in older adults and assess whether sex or CRF influences Tsk. Methods Ninety-two participants (41 women, 68.48 ± 3.01 years) were examined with a thermographic camera in a conditioned room (23.02 ± 3.01 °C) at rest and after a graded protocol. The Tsk of 25 regions of interest (ROIs) were extracted and analysed. Results Men had higher overall Tsk at rest in 76% of ROIs, showing significant differences (p < 0.010) in six specific ROIs, independent of CRF. Both sexes had similar Tsk responses after graded exercise, with increases in distal parts (1.06 ± 0.50 °C), decreases in proximal parts (−0.62 ± 0.42 °C), and stable central Tsk (0.23 ± 0.59 °C). Increases in lower limb Tsk were significantly associated with CRF in men and women (β = 0.438, p = 0.001, and β = 0.535, p < 0.001, respectively), explaining 17% and 27% of the variance, respectively. Conclusions This study demonstrates a sex-specific effect on resting Tsk in older adults, suggesting that sex-specific Tsk patterns should be considered when analysing Tsk in this population. Additionally, the association between increases in lower limb Tsk and CRF suggests that Tsk could be a promising predictor of CRF in older adults.Spanish Ministry of Economy, Industry and Competitiveness (MINECO)European Regional Development Fund (FEDER) (grant number: DEP 2016-76123-R)FEDER/ Junta de Andalucía-Consejeria de Salud y Familias (grant number PI- 0002-2017)Biomedical Research Networking Center on Frailty and Healthy Aging (CIBERFES)FEDER funds from the European Union (CB16/10/00477)Margarita Salas Postdoctoral ProgramEuropean Union Next GenerationE

Influence of Exercise on the Human Gut Microbiota of Healthy Adults: A Systematic Review

SUPPLEMENTARY MATERIAL accompanies this paper at http://links.lww.com/CTG/A166OBJECTIVES: To summarize the literature on the influence of exercise on the gut microbiota of healthy adults. METHODS: A systematic and comprehensive search in electronic database, including SciELO, Scopus, PubMed, and Web of Science up to July 5, 2019. Eligibility criterion was original studies conducted on healthy humans including exercise interventions or interventions involving any type of physical activity. RESULTS: The initial search retrieved 619 articles of which 18 met the inclusion criteria, 9 were observational, 4 reported very short-term exercise interventions, and 5 reported medium/long-term exercise interventions. Higher levels of physical activity or cardiorespiratory fitness were positively associated with fecal bacterial alpha diversity. Contrasting associations were detected between both the level of physical activity and cardiorespiratory fitness and fecal counts for the phyla Firmicutes, Bacteroidetes, and Proteobacteria. Higher levels of physical activity and cardiorespiratory fitness were positively associated with the fecal concentration of short-chain fatty acids. Reports on the effects of very shortterm and medium/long-term exercise interventions on the composition of the gut microbiota were inconsistent. DISCUSSION: Higher levels of physical activity and cardiorespiratory fitness are associated with higher fecal bacterial alpha diversity and with the increased representation of some phyla and certain short-chain fatty acids in the feces of healthy adults. Very short-term and medium/long-term exercise interventions seem to influence the fecal counts of some phyla. However, the heterogeneity between studies hampers any strong conclusions from being drawn. Better-designed studies are needed to unravel the possible mechanisms through which exercise might influence the composition and activity of the human gut microbiota.The 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), Retos de la Sociedad (DEP2016-79512-R), and European Regional Development Funds (ERDF), by the Spanish Ministry of Education (FPU 16/05159 and FPU17/01523), the Fundación Iberoamericana de Nutrición (FINUT), the Redes Temáticas De Investigación Cooperativa RETIC (Red SAMID RD16/0022), AstraZeneca HealthCare Foundation, the University of Granada Plan Propio de Investigación 2016 (Excellence actions: Unit of Excellence on Exercise and Health [UCEES]), and by the Junta de Andalucía, Consejería de Conocimiento, Investigación y Universidades (ERDF, SOMM17/ 6107/UGR). B.M.-T. is supported by individual postdoctoral grants from the Fundación Alfonso Martin Escudero

Plasma Levels of Bile Acids Are Related to Cardiometabolic Risk Factors in Young Adults

The study was supported by the Spanish Ministry of Economy and Competitiveness via Retos de la Sociedad (DEP2016-79512-R to J.R.R.) and European Regional Development Funds (ERDF), the Spanish Ministry of Education (FPU 16/02828), the University of Granada Plan Propio de Investigacion 2016-Excellence actions: Unit of Excellence on Exercise and Health (UCEES), the Junta de Andalucia, Consejeria de Conocimiento, Investigacion y Universidades (ERDF: ref. SOMM17/6107/UGR), The Netherlands CardioVascular Research Initiative "the Dutch Heart Foundation, Dutch Federation of University Medical Centers, the Netherlands Organisation for Health Research and Development and the Royal Netherlands Academy of Sciences" (CVON2017-20 GENIUS-2) to P.C.N.R., and the Chinese Scholarship Council (CSC; No. 201707060012 to X.D., No. 201607060017 to W.Y.). B.M.T. is supported by an individual postdoctoral grant from the Fundacion Alfonso Martin Escudero.Context: Bile acids (BA) are known for their role in intestinal lipid absorption and can also play a role as signaling molecules to control energy metabolism. Prior evidence suggests that alterations in circulating BA levels and in the pool of circulating BA are linked to an increased risk of obesity and a higher incidence of type 2 diabetes in middleaged adults. Objective: We aimed to investigate the association between plasma levels of BA with cardiometabolic risk factors in a cohort of well-phenotyped, relatively healthy young adults. Methods: Body composition, brown adipose tissue, serum classical cardiometabolic risk factors, and a set of 8 plasma BA (including glyco-conjugated forms) in 136 young adults (age 22.1 ± 2.2 years, 67% women) were measured. Results: Plasma levels of chenodeoxycholic acid (CDCA) and glycoursodeoxycholic acid (GUDCA) were higher in men than in women, although these differences disappeared after adjusting for body fat percentage. Furthermore, cholic acid (CA), CDCA, deoxycholic acid (DCA), and glycodeoxycholic acid (GDCA) levels were positively, yet weakly associated, with lean body mass (LBM) levels, while GDCA and glycolithocholic acid (GLCA) levels were negatively associated with 18F-fluorodeoxyglucose uptake by brown adipose tissue. Interestingly, glycocholic acid (GCA), glycochenodeoxycholic acid (GCDCA), and GUDCA were positively associated with glucose and insulin serum levels, HOMA index, low-density lipoprotein cholesterol, tumor necrosis factor alpha, interleukin (IL)-2, and IL-8 levels, but negatively associated with high-density lipoprotein cholesterol, ApoA1, and adiponectin levels, yet these significant correlations partially disappeared after the inclusion of LBM as a confounder. Conclusion: Our findings indicate that plasma levels of BA might be sex dependent and are associated with cardiometabolic and inflammatory risk factors in young and relatively healthy adults.Spanish Ministry of Economy and Competitiveness via Retos de la Sociedad DEP2016-79512-REuropean Commission Spanish Government FPU 16/02828University of Granada Plan Propio de Investigacion 2016-Excellence actions: Unit of Excellence on Exercise and Health (UCEES)Consejeria de Conocimiento, Investigacion y Universidades (ERDF) SOMM17/6107/UGRNetherlands CardioVascular Research Initiative "the Dutch Heart Foundation" CVON2017-20 GENIUS-2 Netherlands CardioVascular Research Initiative "Dutch Federation of University Medical Centers" CVON2017-20 GENIUS-2Netherlands CardioVascular Research Initiative "Netherlands Organisation for Health Research and Development" CVON2017-20 GENIUS-2 Netherlands CardioVascular Research Initiative "Royal Netherlands Academy of Sciences" CVON2017-20 GENIUS-2China Scholarship Council 201707060012 201607060017Fundacion Alfonso Martin EscuderoJunta de Andaluci

Association of Neck Circumference with Anthropometric Indicators and Body Composition Measured by DXA in Young Spanish Adults

Background: Due to a clinical and public health interest of neck circumference (NC), a better understanding of this simple anthropometric measurement, as a valid marker of body composition is necessary. Methods: A total of 119 young healthy adults participated in this study. NC was measured over the thyroid cartilage and perpendicular to the longitudinal axis of the neck. Body weight, height, waist circumference (WC), and hip circumference were measured. A Dual X-ray absorptiometry (DXA) scan was used to determine fat mass, lean mass, and visceral adipose tissue (VAT). Additionally, body mass index (BMI) and triponderal mass index (TMI), the waist to hip and waist to height ratios, and the fat mass and lean mass indexes (FMI and LMI, respectively) were calculated. Results: NC was positively associated in women (W) and men (M), with BMI (rW = 0.70 and rM = 0.84, respectively), TMI (rW = 0.63 and rM = 0.80, respectively), WC (rW = 0.75 and rM = 0.86, respectively), VAT (rW = 0.74 and rM = 0.82, respectively), Waist/hip (rW = 0.51 and rM = 0.67, respectively), Waist/height (rW = 0.68 and rM = 0.83, respectively) and FMI (rW = 0.61 and rM = 0.81, respectively). The association between NC and indicators of body composition was however weaker than that observed by BMI, TMI, WC and Waist/height in both women and men. It is of note that in women, NC was associated with FMI, VAT and LMI independently of BMI. In men, adding NC to anthropometric variables did not improve the prediction of body composition, while slight improvements were observed in women. Conclusions: Taken together, the present study provides no indication for NC as a useful proxy of body composition parameters in young adults, yet future studies should explore its usefulness as a measure to use in combination with BMI, especially in women.This study was supported by the Spanish Ministry of Economy and Competitiveness Grants (DEP2016-79512-R and PTA 12264-I), Fondo de Investigación Sanitaria del Instituto de Salud Carlos III (PI13/01393), and Retos de la Sociedad (DEP2016-79512-R), Fondos Estructurales de la Unión Europea (FEDER), by the Spanish Ministry of Education (FPU 13/04365), by the Fundación Iberoamericana de Nutrición (FINUT), by the Redes temáticas de investigación cooperativa RETIC (Red SAMID RD16/0022), by AstraZeneca HealthCare Foundation and by the University of Granada, Plan Propio de Investigación 2016, Excellence actions: Units of Excellence; Scientific Unit of Excellence on Exercise and Health (UCEES), Plan Propio de Investigación 2018: Programa Contratos-Puente and Programa Perfeccionamiento de Doctores, by the Junta de Andalucía, Consejería de Conocimiento, Investigación y Universidades, the European Regional Development Funds (ref. SOMM17/6107/UGR), by the Fundación Alfonso Martín Escudero, and by the Fundación Carolina (C.2016-574961). This study is part of a Ph.D. Thesis conducted in the Biomedicine Doctoral Studies of the University of Granada, Spain

Impact of cow's milk intake on exercise performance and recovery of muscle function: a systematic review

Dairy products are thought to improve recovery after both resistance and endurance exercises due to their nutritional proprieties. We systematically reviewed the effects of dairy product intake on exercise performance and recovery of muscle function in humans. A literature search was conducted in the MEDLINE (via PubMed) and Web of Science databases from their inception to 15th April 2018. The initial search retrieved 7708 articles, and a total of 11 studies were finally included after applying inclusion and exclusion criteria. All the selected studies were conducted with cow's milk. Whereas some studies found significant positive effect of cow's milk on exercise performance and recovery of muscle function, others did not find any effect. These controversies could be due to the heterogeneity of cow's milk ingestion (e.g., amount of cow's milk, timing of consuming the cow's milk), to the type of intervention, and to the large heterogeneity of outcomes measured. Limited studies exist examining the effects of cow's milk consumption and its influence on exercise performance and recovery of muscle function, therefore further studies are needed to draw more definitive conclusions.The study was supported by the Spanish Ministry of Education (FPU 13/04365 and 15/04059), by the Redes temáticas de investigación cooperativa RETIC (Red SAMID RD16/0022), and by the University of Granada Plan Propio de Investigacion 2016 -Excellence actions: Unit of Excellence on Exercise and Health (UCEES) - and Plan Propio de Investigación 2018 - Programa Contratos-Puente, and the Junta de Andalucía, Consejería de Conocimiento, Investigación y Universidades (ERDF: ref. SOMM17/6107/UGR), and by the Interprofessional Dairy Organization (INLAC) of Spain

Omega-6 and omega-3 oxylipins as potential markers of cardiometabolic risk in young adults

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, Retos de la Sociedad (DEP2016-79512-R) and the European Regional Development Fund (ERDF), the Spanish Ministry of Education (FPU16/02828 and FPU19/01609), the Fundacion Iberoamericana de Nutricion (FINUT), the Redes Tematicas de Investigacion Cooperativa RETIC (Red SAMID RD16/0022), the AstraZeneca HealthCare Foundation, the University of Granada Plan Propio de Investigacion 2016 Excellence actions: Unit of Excellence on Exercise and Health (UCEES), the Junta de Andalucia, Consejeria de Conocimiento, Investigacion y Universidades (ERDF; ref. SOMM17/6107/UGR and DOC 01151), the Fundacion Alfonso Martin Escudero, the Netherlands CardioVascular Research Initiative: the Dutch Heart Foundation, Dutch Federation of University Medical Centers, the Netherlands Organisation for Health Research and Development and the Royal Netherlands Academy of Sciences (CVON2017-20 GENIUS-2) to PCNR, and the Chinese Scholarship Council (CSC, No. 201707060012).Objective: Omega-6 and omega-3 oxylipins are known to play a role in inflammation and cardiometabolic diseases in preclinical models. The associations between plasma levels of omega-6 and omega-3 polyunsaturated fatty acid–derived oxylipins and body composition and cardiometabolic risk factors in young adults were assessed. Methods: Body composition, brown adipose tissue, traditional serum cardiometabolic risk factors, inflammatory markers, and a panel of 83 oxylipins were analyzed in 133 young adults (age 22.1[SD 2.2] years, 67% women). Results: Plasma levels of four omega-6 oxylipins (15-HeTrE, 5-HETE, 14,15-EpETrE, and the oxidative stress–derived 8,12-iso- iPF2α -VI) correlated positively with adiposity, prevalence of metabolic syndrome, fatty liver index, and homeostatic model assessment of insulin resistance index and lipid parameters. By contrast, the plasma levels of three omega-3 oxylipins (14,15-DiHETE, 17,18-DiHETE, and 19,20-DiHDPA) were negatively correlated with adiposity, prevalence of metabolic syndrome, fatty liver index, homeostatic model assessment of insulin resistance index, and lipid parameters. The panel of seven oxylipins predicted adiposity better than traditional inflammatory markers such as interferon gamma or tumor necrosis factor-alpha. Pathway analyses revealed that individuals with obesity had higher plasma levels of omega-6 and lower plasma levels of omega-3 oxylipins than normal-weight individuals. Conclusion: Plasma levels of seven omega-6 and omega-3 oxylipins may have utility as early markers of cardiometabolic risk in young adults.Spanish Government PI13/01393Retos de la Sociedad DEP2016-79512-REuropean Commission Spanish Government FPU16/02828 FPU19/01609Fundacion Iberoamericana de Nutricion (FINUT)Redes Tematicas de Investigacion Cooperativa RETIC Red SAMID RD16/0022AstraZenecaUniversity of Granada Plan Propio de Investigacion Excellence actions: Unit of Excellence on Exercise and Health (UCEES)Junta de Andalucia Consejeria de Conocimiento, Investigacion y Universidades (ERDF) SOMM17/6107/UGR DOC 01151Fundacion Alfonso Martin EscuderoNetherlands CardioVascular Research Initiative: the Dutch Heart FoundationDutch Federation of University Medical CentersNetherlands Organization for Health Research and DevelopmentRoyal Netherlands Academy of Sciences CVON2017-20 GENIUS-2China Scholarship Council 201707060012 PTA-1226

Infrared Thermography for Estimating Supraclavicular Skin Temperature and BAT Activity in Humans: A Systematic Review

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 18F-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 IRTmeasured SST; at present, IRT cannot determine whether any increase in SST is due to increased BAT activity.This study was supported by the Spanish Ministry of Economy and Competitiveness (MINECO) via the Fondo de Investigación Sanitaria del Instituto de Salud Carlos III (PI13/01393), Retos de la Sociedad (DEP2016-79512-R) and European Regional Development Funds (ERDF), 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), and Plan Propio de Investigación 2018 and the Junta de Andalucía, Consejería de Conocimiento, Investigación y Universidades (ERDF: SOMM17/6107/UGR). DSI is an Investigator of the Miguel Servet Fund from Carlos III National Institute of Health, Spain (CP15/00106). DJP is supported by grants from the Spanish Ministry of Science and Innovation-MINECO (RYC-2014-16938), MINECO/European Fund for Regional Development (FEDER) (DEP2016-76123-R), the Government of Andalusia, the Integrated Territorial Initiative 2014-2020 for the Province of Cádiz (PI-0002-2017), the European Union's ERASMUS+SPORT program (Grant Agreement 603121-EPP-1-2018-1-ES-SPO-SCP), and the EXERNET Research Network on Exercise and Health in Special Populations (DEP2005-00046/ACTI)

Association of shivering threshold time with body composition and brown adipose tissue in young adults

Purpose: Brown adipose tissue (BAT) increases metabolic heat production in response to cold exposure. Body size and composition are involved in the human cold response, yet the influence of BAT herein have not fully been explored. Here, we aimed to study the association of the cold-induced shivering threshold time with body composition, BAT, the perception of shivering and skin temperature in young adults. Methods: 110 young healthy adults (81 females; age = 21.7 ± 2.1 years, BMI = 24.2 ± 4.3 kg/m2) underwent 2 h of individualized cooling, followed by the quantification of BAT using a18F-fluorodeoxyglucose ([18F]FDG) positron emission tomography-computed tomography (PET-CT) scan. Body mass index (BMI), lean mass, fat mass and body surface area (BSA) were also measured. Shivering threshold time was defined as the time until shivering occurred using an individualized cooling protocol. Results: The shivering threshold time was on average 116.1 min for males and 125.8 min for females, and was positively associated to BMI (β = 3.106; R2 = 0.141; p = 0.001), lean mass (β = 2.295; R2 = 0.128; p = 0.001) and fat mass (β = 1.492; R2 = 0.121; p = 0.001) in females, but not in males (all p ≥ 0.409). The shivering threshold time was positively associated with BSA in males (p = 0.047) and females (p = 0.001), but it was not associated with BAT volume or [18F]FDG uptake nor with the perception of shivering and skin temperature perception in both sexes. Conclusion: The shivering threshold time is positively associated with whole-body adiposity and lean mass in females, but not in males. The shivering threshold time was positively associated with BSA, but no association was observed with BAT nor with the perception of shivering or skin temperature. Future research should consider the influence of body composition when applying cooling protocols among individuals with different phenotypical features.Spanish Government PI13/01393 PTA 12264-IRetos de la Sociedad DEP 2016-79512-REuropean CommissionSpanish Government FPU 13/03410Fundacion Iberoamericana de Nutricion (FINUT)Redes Tematicas de Investigacion Cooperativa RETIC Red SAMID RD16/0022AstraZenecaUniversity of Granada Plan Propio de Investigacion 2016 - Excellence actions: Unit of Excellence on Exercise and Health (UCEES)Plan Propio de Investigacion 2018: Programa ContratosPuenteJunta de Andalucia, Consejeria de Conocimiento, Investigacion y Universidades (ERDF) SOMM17/6107/UGRFundacion Carolina C.2016-574,961Fundacion Alfonso Martin EscuderoMinisterio de Universidades y la Union Europea-NextGenerationEU RR_C_2021_0

Distribution of Brown Adipose Tissue Radiodensity in Young Adults: Implications for Cold [18F]FDG-PET/CT Analyses

Procedures: We measured 125 individuals after a personalized cooling protocol with a static [18F]FDG-PET/CT scan. We quantified BAT using different combination of threshold in every single HU for all participants. Results: We observed that the SUV threshold influences BAT quantification by [18F]FDG-PET/ CT scans more than the HU range. We found that the range from − 50 to − 10 HU had the highest proportion of total BAT volume (43.2 %), which represents 41.4 % of the total BAT metabolic activity in our cohort. We also observed that BAT volume was not different between categories of body mass index, as well as BAT activity (SUVmean). In addition, BAT was less dense in women than in men, although the BAT activity (SUVmean) was higher in all ranges of HU. We also observed that the radiodensity of BAT located in the cervical area was mainly in the range from − 50 to − 10 HU. Conclusion: Therefore, all future human studies using static [18F]FDG-PET/CT scans should include BAT in the radiodensity range from − 50 to − 10 HU.This study was supported by the Spanish Ministry of Economy and Competitiveness, Fondo de Investigación Sanitaria del Instituto de Salud Carlos III (PI13/01393) and Retos de la Sociedad (DEP2016-79512-R), Fondos Estructurales de la Unión Europea (FEDER), by the Spanish Ministry of Education (FPU 13/04365), by 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) - and Plan Propio de Investigación 2018 - Programa Contratos-Puente, and the Junta de Andalucía, Consejería de Conocimiento, Investigación y Universidades (FEDER, ref. SOMM17/6107/UGR)