Structural and hydrogeological features of a Lias carbonate aquifer in the Triffa Plain, NE Morocco

The rising demand for water and the contamination of shallow water table aquifers has led authorities in NE Morocco to look for deeper groundwater resources in the Triffa Plain, namely in Lower Jurassic (Lias) dolomitic limestones. The liassic aquifer is of strategic importance for the development of the region, however, its hydrodynamic behaviour is poorly understood due to lack of hydrogeological data and block structure. This article presents a first effort towards understanding the structure and hydraulic behaviour of the aquifer. Exploration borehole data and results from geophysical campaigns were integrated into a GIS environment to build a preliminary model of the aquifer structure. The aquifer behaves as an unconfined aquifer in the northern part of the Béni Snassen Mountains (the recharge area), but as it dips to the north, it becomes confined by marls and shales of the Middle/Upper Jurassic. Even though piezometric level data are scarce, a tentative piezometric map was produced. Three blocks separated by NW–SE trending faults in a horst and graben structure, with distinct flow behaviours were identified: Berkane, Fezouane and Sidi Rahmoun blocks. Those blocks also show differences in hydraulic conductivity distribution. As a result of the reaction with the dolomitic limestones, the groundwater is of calcium-magnesium bicarbonate type. Groundwater temperature as measured in springs ranges from 29 C to 37 C in springs and constitutes a potential low enthalpy geothermal resource

Linking cardiorespiratory fitness classification criteria to early subclinical atherosclerosis in children

It is unclear if cardiorespiratory fitness (CRF) can be used as a screening tool for premature changes in carotid intima-media thickness (cIMT) in paediatric populations. The purpose of this cross-sectional study was 3-fold: (i) to determine if CRF can be used to screen increased cIMT; (ii) to determine an optimal CRF cut-off to predict increased cIMT; and (iii) to evaluate its ability to predict increased cIMT among children in comparison with existent CRF cut-offs. cIMT was assessed with high-resolution ultrasonography and CRF was determined using a maximal cycle test. Receiver operating characteristic analyses were conducted in boys (n = 211) and girls (n = 202) aged 11-12 years to define the optimal sex-specific CRF cut-off to classify increased cIMT (≥75th percentile). Logistic regression was used to examine the association between the CRF cut-offs with the risk of having an increased cIMT. The optimal CRF cut-offs to predict increased cIMT were 45.81 and 34.46 mL·kg(-1)·min(-1) for boys and girls, respectively. The odds-ratios for having increased cIMT among children who were unfit was up to 2.8 times the odds among those who were fit (95% confidence interval: 1.40-5.53). Considering current CRF cut-offs, only those suggested by Adegboye et al. 2011. (Br. J. Sports Med. 45(9): 722-728) and Boddy et al. 2012 (PLoS One, 7(9): e45755) were significant in predicting increased cIMT. In conclusion, CRF cut-offs (boys: ≤ 45.8; girls: ≤ 34.5 mL·kg(-1)·min(-1)) are associated with thickening of the arterial wall in 11- to 12-year-old children. Low CRF is an important cardiovascular risk factor in children and our data highlight the importance of obtaining an adequate CRF.info:eu-repo/semantics/publishedVersio

Cross-sectional and prospective impact of reallocating sedentary time to physical activity on children's body composition.

BACKGROUND: The amount of time children spend in sedentary behaviours may have adverse health effects. OBJECTIVE: To examine the substitution effects of displacing a fixed duration of sedentary time with physical activity (PA) on children's body composition. METHODS: We included 386 children (197 boys). Outcomes were body mass index, waist circumference, total body fat mass and trunk fat mass assessed by dual-energy X-ray absorptiometry. Sedentary time and PA were measured with accelerometers. Data were analysed by isotemporal analyses estimating the effect of reallocating 15 and 30 min d-1 of sedentary time into light (light physical activity), and moderate-to-vigorous (MVPA) PA on body composition. RESULTS: Reallocating 15 and 30 min d-1 of sedentary time into MVPA was negatively associated with body fatness in cross-sectional analyses. Prospectively, reallocating 30 min of sedentary time into 30 min of MVPA was negatively associated with waist circumference (β = -1.11, p  0.05) with body fatness outcomes. CONCLUSIONS: Substituting sedentary time with MVPA using isotemporal analysis is associated with positive effects on body composition.The study was supported by the Portuguese Foundation of Science and Technology. Support/grant: PTDC/DES/108372/2008

NEW EQUATIONS TO DETERMINE EXERCISE INTENSITY USING DIFFERENT EXERCISE MODES

The purpose of this study was to determine new equations from the relationship of %·VO2max versus %HRmax, based on direct measures of oxygen uptake, in four exercise modes (leg cycling, rowing, stepping and running), in young adult females and males with low risk for cardiovascular disease. Ten adult males and ten females volunteered for the study. The participants performed an incremental test for each exercise mode until exhaustion. Regression analyses were carried out for each participant at a target % of VO2max and %HRmax was computed. At 40-90%·VO2max, the regression equations predicted similar values of %HRmax for males and females in the four exercise modes. In contrast, estimated %HRmax for cycling was higher at 40-70%·VO2max, when compared with stepping and running. The results support the notion that a single equation to predict target heart rate values for both males and females can be applied. Furthermore, at light and moderate intensities, leg cycling produces different %·VO2max-%HRmax regression equations than stepping and running

a systematic review in children and adolescents aged 6-18 years

© Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.OBJECTIVE: This report aimed to systematically review the evidence for a differential association between objective and self-reported physical activity and cardiorespiratory fitness on academic achievement. DESIGN: Systematic review. DATA SOURCES: Studies were identified from searches in Embase, Education Resources Information Center, PubMed, PsycINFO, SPORTdiscus and Web of Science databases from January 2000 to December 2016. ELIGIBILITY CRITERIA FOR SELECTING STUDIES: Eligibility criteria included cross-sectional, longitudinal and interventional study designs. Outcomes included students' school grade or a standardised test or measure of academic achievement. Explanatory variables were cardiorespiratory fitness and objective and self-reported physical activity. Inclusion criteria included school-aged children and adolescents aged-18 years (or students from primary to secondary school when student's participants age was not described) and articles published in English, Portuguese or Spanish. RESULTS: A total of 51 articles met inclusion criteria: 41 cross-sectional, 2 intervention and 8 longitudinal studies. Results from 11 studies were inconsistent regarding the relationship between objectively measured physical activity and academic achievement. Ten of the 16 articles reported positive associations between self-reported physical activity and academic achievement. From the 22 studies that analysed the relationship between cardiorespiratory fitness and academic achievement, it was verified that they all generally support the beneficial effect of cardiorespiratory fitness on students' academic achievement. CONCLUSION: Higher cardiorespiratory fitness may be important to enhance children and adolescents' health and, additionally, academic achievement. Due to a lack of consensus across studies, methodological issues associated with the assessment of physical activity should be considered when investigating physical activity and academic achievement.publishe

Promoting health-related cardiorespiratory fitness in physical education : a systematic review

Copyright: © 2020 Peralta et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.Background: This article aimed to systematically review the contribution of physical education (PE) classes to improve cardiorespiratory fitness (CRF) in children and adolescents; and to define potentially relevant factors for promoting CRF in PE classes. Methods: Studies were identified from searches in ERIC, PubMed, SPORTDiscus, and Web of Science databases. Primary source articles, relating PE classes and CRF, published up to July 2019 in peer-reviewed journals were eligible for inclusion. Specific inclusion criteria were: (a) having cross-sectional or longitudinal and observational or interventional study designs; (b) targeting school-aged children or adolescents; (c) measuring CRF, heart rate or CRF test results as an outcome; (d) having statistical analyses of the CRF, heart rate or CRF test results outcomes reported; (e) focusing on PE classes or PE interventions that did not extended time or frequency of the classes; and (f) published in English, French, Portuguese, or Spanish. Results: A total of 24 studies met the inclusion criteria. Overall, 10 studies have found a neutral effect of PE classes in students’ CRF, eight studies found that PE indeed contributed to the improvement of CRF and six studies revealed mixed findings, when PE classes where controlled for others variables (e.g. body mass index, intensity). Higher intensity PE classes consistently demonstrated contributions to improving students’ CRF. Conclusion: Review findings suggest that PE classes can contribute to the improvement of students’ CRF. Intensity, age and weight status were identified as potentially relevant factors for promoting CRF in PE classes. To improve CRF, higher intensity classes should be provided.MP is supported by a PhD scholarship grant (SFRH/BD/122219/2016) from the Portuguese Science and Technology Foundation (https://www.fct.pt/). The funder had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.info:eu-repo/semantics/publishedVersio

TBW Assessment by Deuterium Dilution in Spanish Adolescents

Congreso para especialistas en Nutrición, Actividad Física y Composición CorporalINTRODUCTION: Total body water (TBW) assessment is a cornerstone in order to validate equations to estimate body composition components as fat mass and fat free mass. Deuterium dilution technique (D2DT) is considered the gold standard method to assess TBW, however in Spain there are not any reference data using D2DT. The knowledge of specific references for Spanish population must be a goal for the biological studies of Spanish people. OBJECTIVE: It was our aim to assess TBW using the D2DT in a sample of Spanish adolescents. METHODS: 224 specimens of urine from 150 adolescents (113 girls and 111 boys) were taken to analyze. A dose of 0.1 grams of 2D2O per Kg of body weight was administrated; afterwards it was followed by 4-hours stabilization period. The isotope (deuterium oxide (D2O)) dilution method was used to measure TBW with an isotope-ratio mass-spectrometer. Averages by sex and Tanner stages were calculated for %TBW and TBW. General lineal model were used to analyze differences and interactions between groups. RESULTS: %TBW was significantly different between boys and girls (58.98_5.59% vs 55.5_4.28%, P0.05). CONCLUSIONS: This study has been the first in Spain, which have measured TBW in vivo using D2DT. These data can be useful to validate new methods and equations from bioimpedance analysis to estimate TBW.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech. Coca-Col

A New Approach to Express Regional Adiposity and Its Association with Blood Lipids, Inflammation and Insulin Resistance Markers

Regional adiposity is classically related with inflammation, insulin resistance (IR) and an altered blood lipid profile. Traditionally, central adiposity expressed as a ratio (%FM) = fat mass/total mass of the region is the variable most used in research. However, this ratio does not account for total bodily fat mass (TFM). So, a great accumulation in a region, where lean mass is more important than fat, could be more associated with risk factors than other with less absolute fat (kg) but higher percentage (in instance abdomen). PURPOSE: To analyse the associations between the ratio (RW) = regional fat mass (kg) / TFM (kg) and blood lilid profile, IR and inflammation. METHODS: Sixty-two pre-menopausal and healthy women were recruited for this study (age, 39.6 ±7.2 years; BMI, 29.2 ±4.2 kg.m-2; total %TFM, 42.0 ±5.9%). Weight and height were measured to the nearest 0.1 kg and 0.1 cm respectively, and body composition was estimated with dual energy x-ray aborptiometry. RWF were calculated for trunk (RWT), lower limbs (RWLL) and upper limbs (RWUL). Insulin, glycaemia and insulin sensitivity (HOMA) were the IR markers. C-reactive protein (CRP) and Tumour Necrosis Factor (TNF-α) were the inflammation variables. Total cholesterol (TC), low-density lipoprotein (LDL), high-density lipoprotein (HDL) and triglycerides (TG) were also measured. Partial correlations adjusted to TFM between RW and blood markers were carried out. RESULTS: Significant correlations were found between RWUL and HOMA (r=0.276, P<0.05), TG (r=0.292, P<0.05) and insulin (r=0.271, P<0.05). RWT was also correlated with blood lipids: TG (r=0.278, P<0.05) and LDL (r=-0.318, P<0.05). Finally, RWLL was the ratio with more number of associations: HOMA (r=-0.274, P<0.05), TG (r=-0.342, P<0.01), LDL (r=0.317, P<0.05) and insulin (r=-0.253, P<0.05). Abdominal and trunk %FM were only correlated with HOMA (r=0.380, P<0.01) and LDL (r=0.264, P<0.05) respectively. CONCLUSION: In our sample, regional fat mass contribution (RW) for whole body FM showed more associations with blood markers than classical ratios (regional %FM). These findings highlighted RW ratios were well correlated with inflammatory and IR risk factors, which in turn could be useful to express positive or negative results in future studies. This issue requires further investigation.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tec

Accuracy of DXA in estimating body composition changes in elite athletes using a four compartment model as the reference method

<p>Abstract</p> <p>Background</p> <p>Dual-energy x-ray absorptiometry (DXA) provides an affordable and practical assessment of multiple whole body and regional body composition. However, little information is available on the assessment of changes in body composition in top-level athletes using DXA. The present study aimed to assess the accuracy of DXA in tracking body composition changes (relative fat mass [%FM], absolute fat mass [FM], and fat-free mass [FFM]) of elite male judo athletes from a period of weight stability to prior to a competition, compared to a four compartment model (4C model), as the criterion method.</p> <p>Methods</p> <p>A total of 27 elite male judo athletes (age, 22.2 ± 2.8 yrs) athletes were evaluated. Measures of body volume by air displacement plethysmography, bone mineral content assessed by DXA, and total-body water assessed by deuterium dilution were used in a 4C model. Statistical analyses included examination of the coefficient of determinant (r²), standard error of estimation (SEE), slope, intercept, and agreement between models.</p> <p>Results</p> <p>At a group level analysis, changes in %FM, FM, and FFM estimates by DXA were not significantly different from those by the 4C model. Though the regression between DXA and the 4C model did not differ from the line of identity DXA %FM, FM, and FFM changes only explained 29%, 36%, and 38% of the 4C reference values, respectively. Individual results showed that the 95% limits of agreement were -3.7 to 5.3 for %FM, -2.6 to 3.7 for FM, and -3.7 to 2.7 for FFM. The relation between the difference and the mean of the methods indicated a significant trend for %FM and FM changes with DXA overestimating at the lower ends and underestimating at the upper ends of FM changes.</p> <p>Conclusions</p> <p>Our data indicate that both at group and individual levels DXA did not present an expected accuracy in tracking changes in adiposity in elite male judo athletes.</p