Explore the vast range of titles available.

Background Soccer is one of the most attractive sports around the globe for children and adolescents, and the benefits of soccer training are often shown. Due to the intermittent character of soccer with random changes between high-intensity activity and low-intensity play, athletes’ aerobic (respiratory) capacity is specifically stimulated. However, little is known about the effects of regular soccer practice on pulmonary diffusion capacity (TL) in young players, even though it is the most popular sport in the world. Objectives To analyze the effects of 28 weeks of regular soccer training versus a non-activity control period on the TL, the alveolar-capillary membrane diffusion capacity (DM) as well as the capillary blood volume (Vc) in healthy prepubertal boys aged 6 to 10 years. Methods For this purpose, boys were randomly assigned to a soccer training group (SG, n = 40) or a control group (CG, n = 40). Pre and post-intervention, all participants performed an all-out graded bicycle ergometer test to measure maximal oxygen uptake (VO 2max ) and maximal aerobic power (MAP). A respiratory maneuver was performed at rest and just at the end of the test to measure the TL for carbon monoxide (TL CO ) and nitric oxide (TL NO ), DM, as well as Vc. Results There were no significant baseline between-group differences for any of the assessed parameters (p > 0.05). Significant group-by-time interactions were found for most pulmonary parameters measured at rest (p < 0.05), with effect size (ES) values ranging from small-to-large (0.2 < ES < 4.0), except for VA (p = 0.3, ES = 0.006). Post-hoc tests indicated significant DM (p < 0.05; 0.2 < ES < 4.0), TL NO (p < 0.01; 0.22 < ES < 4.0), TL CO (p < 0,01; 0.24 < ES < 4.0) and Vc (p = 0.01; 0.404 < ES < 0.6) improvements for SG but not CG. Significant group-by-time effects were identified for HRmax and VO 2 max (p < 0.001; ES = 0.5 and p = 0.005; ES = 0.23 respectively). The post-hoc analyses indicated a significant decrease in HRmax and a significant increase in VO 2 max in the SG (p < 0.001; ES = 0.5 and p = 0.005, ES = 0.23, respectively) but not in CG. Values for TL CO increased by almost 20%; Vc of 14% DM of 8% and VA of 10% at the end of maximal exercise in SG. Furthermore, the percentage improvement was less notable in the control group (7.5% for TL CO ; 2% for Vc; 5% for DM and 4% for VA). Conclusion Regular soccer training significantly improves pulmonary vascular function and increases DM and Vc after exercise in prepubertal boys. The observed adaptations are most likely due to better recruitment of additional pulmonary capillary function. However, the stepwise linear regression analyses indicated that increases in pulmonary vascular function were not related to improvements in VO 2max and MAP.

This study compared the effects of varying aerobic training programs on pulmonary diffusing capacity (TLCO), pulmonary diffusing capacity for nitric oxide (TLNO), lung capillary blood volume (Vc) and alveolar–capillary membrane diffusing capacity (DM) of gases at rest and just after maximal exercise in young athletes. Sixteen healthy young runners (16–18 years) were randomly assigned to an intense endurance training program (IET, n = 8) or to a moderate endurance training program (MET, n = 8). The training volume was similar in IET and MET but with different work intensities, and each lasted for 8 weeks. Participants performed a maximal graded cycle bicycle ergometer test to measure maximal oxygen consumption (VO2max) and maximal aerobic power (MAP) before and after the training programs. Moreover, TLCO, TLNO and Vc were measured during a single breath maneuver. After eight weeks of training, all pulmonary parameters with the exception of alveolar volume (VA) and inspiratory volume (VI) (0.104 < p < 0889; 0.001 < ES < 0.091), measured at rest and at the end of maximal exercise, showed significant group × time interactions (p < 0.05, 0.2 < ES < 4.0). Post hoc analyses revealed significant pre-to-post decreases for maximal heart rates (p < 0.0001, ES = 3.1) and improvements for VO2max (p = 0.006, ES = 2.22) in the IET group. Moreover, post hoc analyses revealed significant pre-to-post improvements in the IET for DM, TLNO, TLCO and Vc (0.001 < p < 0.0022; 2.68 < ES < 6.45). In addition, there were increases in Vc at rest, VO2max, TLNO and DM in the IET but not in the MET participants after eight weeks of training with varying exercise intensities. Our findings suggest that the intensity of training may represent the most important factor in increasing pulmonary vascular function in young athletes.

This study aimed to examine the association between aerobic performance (AP) and match running performance (MRP) in elite soccer players when statistically controlling for playing position and contextual factors. AP was tested at the beginning of the season, including maximal oxygen uptake (V̇ O2max), anaerobic threshold (AnT), maximal aerobic speed (MAS), and Yo-Yo Intermittent Recovery Test Level 2 (Yo-Yo IRT2) score. MRP was measured using GPS over a competitive half-season for a total of 216 match performances in elite soccer players, divided into central backs(CBs), full backs(FBs),central midfielders(CMs), wide midfielders (WMs), and strikers. The lowest AP measures were noted among the CBs, while the highest V̇ O2max, AnT, and MAS were recorded among the CMs, CMs and FBs, and FBs, respectively. The CBs had the lowest total distance (TD), high-speed running (HSR; 19.8–25.1 km· h−1) distance, and high-intensity running (HIR; > 19.8 km· h−1) distance; the CMs recorded the greatest TD; and the FBs and WMs covered the greatest HIR distance. Despite the differences in AP and MRP among the players, AP is correlated with MRP independently of the playing position and contextual factors. Higher AP measures were positively associated with the TD, and higher Yo-Yo IRT2 scores were also positively associated with the HSR and HIR distances. The strongest predictors for TD were V̇ O2max and AnT. In conclusion, a higher AP, irrespective of playing position, makes it possible to achieve greater MRPs. This study emphasized the value of integrating AP metrics into individualized training and player role management in elite soccer.

This study aimed to examine the effects of pre-bedtime smartphone use on sleep quality and athletic performance in soccer players while also investigating potential time-of-day variations. In thisrandomized controlled crossover trial, 16 male elite-level players were assigned to either use a smartphone for two hours prior to bedtime or read magazines (control), separated by a one-week washout period. Participants completed morning and afternoon performance tests (cognitive and physical assessments) and sleep quality measurements. Nocturnalsmartphone use significantly impaired sleep quality, increasing sleepiness after days 3 and 5 (p < 0.01; d=5.74, d=5.72, respectively), decreasing total sleep time, increasing sleep onset latency, and reducing sleep efficiency (all p < 0.01; d=1, d=4.59). Cognitive performance initially showed improved afternoon results, although following five days of smartphone use, this pattern reversed with enhanced morning performance (p < 0.01; d=0.53, d=1.48). Simple and choice reaction times deteriorated significantly in afternoon sessions compared to both baseline and control conditions (p < 0.01; d=0.96–3.47). Physical performance tests revealed decreased jumping ability and slower reactive agility times following five nights of smartphone use, particularly in afternoon sessions (p < 0.01; d=0.85 0.91). Five consecutive nights of pre-bedtime smartphone use impaired sleep quality and both cognitive and physical performance in elite soccer players, with stronger effects in afternoon sessions. These findings emphasize the importance of implementing device-free periods prior to bedtime and potentially adjusting training schedules when evening screen exposure is unavoidable. Future research should explore countermeasures for managing evening device exposure in elite athletes.

In both children and adults, acute exercise increases lung capillary blood volume (Vc) and membrane factor (DmCO). We sought to determine whether basketball training affected this adaptation to exercise in children. The purpose of this study was to determine the effects of two years sport activity on the components of pulmonary gas transfer in children. Over a 2-yr period, we retested 60 nine year old boys who were initially separated in two groups: 30 basketball players (P) (9.0 ± 1.0 yrs; 35.0 ± 5.2 kg; 1.43 ± 0.05 m), and matched non players controls (C) (8.9 ± 1.0 yrs; 35.0 ± 6.0 kg; 1.44 ± 0.06 m) who did not perform any extracurricular activity, Vc and DmCO were measured by the NO/CO transfer method at rest and during sub-maximal exercise. Maximal aerobic power and peak power output was 12% higher in the trained group compared to matched controls (p < 0.05). Nitric oxide lung transfer (TLNO) per unit lung volume and thus, DmCO per unit of lung volume (VA) were higher at rest and during exercise in the group which had undergone regular basketball activity compared to matched controls (p < 0.05). Neither lung capillary blood volume nor total lung transfer for carbon monoxide (TLCO) were significantly different between groups. These results suggest that active sport can alter the properties of the lung alveolo-capillary membrane by improving alveolar membrane conductance in children. Key PointsTrained children had greater DmCO/VA and DmCO/Vc ratios compared with control children during exercise.The mechanisms by which basketball playing children were thought to improve lung diffusion are speculative.Further work will be required to determine the kinetics of the alteration in Dm when children switch from non players to players status or vice-versa.

Trace metal elements (TMEs) are among the most important types of pollutants in the environment. Therefore, a precise determination of these contaminants in several environmental components is required for the safety assurance of living organisms. Spectroscopic analysis is an efficient technique employed to detect and determine TME contents in numerous samples. Hence, to achieve reliable and accurate results when using spectroscopic analysis, samples should be carefully prepared. In the present study, the comparison of eight digestion methods of five vegetal samples was carried out to quantify Cd, Mn, Al and Mg contents using the atomic absorption spectroscopy technique. According to the extraction techniques used in this study, results showed an outstanding difference in TME levels determined in the same vegetal sample. The results obtained indicated that the highest Mn concentrations were recorded when using the mixture of HNO3-HClO4 in the studied species: atriplex portulacoides, arthrocnemum indicum, olea europaea BCR-62, ulva lactuca and ulva lactuca BCR-279 compared to all other methods. Regarding the extraction of Cd, our results showed that heated extraction using different acids (HNO3-H2SO4-HClO4, HCl-HNO3, HNO3-HClO4, HNO3-H2SO4, HNO3-HCl-HClO4 and HNO3-HCl-H2SO4) was the most efficient in atriplex portulacoides, arthrocnemum indicum, olea europaea BCR-62, ulva lactuca and ulva lactuca BCR-279. Similarly, these heated acid digestion techniques (efficient for Cd) showed the highest levels of Al in atriplex portulacoides and arthrocnemum indicum. However, for the Mg extraction, our results revealed that the effectiveness of the method used depended on the plant species studied. Regarding these findings, the efficiency of metal quantification by AAS depends on the digestion procedure, the metallic ion to determine and the plant species.

The analysis of vegetation dynamics and agricultural production is essential in semi-arid regions, in particular as a consequence of the frequent occurrence of periods of drought. In this paper, a multi-temporal series of the Normalized Difference of Vegetation Index (NDVI), derived from SPOT-VEGETATION (between September 1998 and August 2013) and TERRA-MODIS satellite data (between September 2000 and August 2013), was used to analyze the vegetation dynamics over the central region of Tunisia in North Africa, which is characterized by a semi-arid climate. Products derived from these two satellite sensors are generally found to be coherent. Our analysis of land use and NDVI anomalies, based on the Vegetation Anomaly Index (VAI), reveals a strong level of agreement between estimations made with the two satellites, but also some discrepancies related to the spatial resolution of these two products. The vegetation’s behavior is also analyzed during years affected by drought through the use of the Windowed Fourier Transform (WFT). Discussions of the dynamics of annual agricultural areas show that there is a combined effect between climate and farmers’ behavior, leading to an increase in the prevalence of bare soils during dry years.

The question of trace metal elements (TME) is still relevant and causes several environmental problems. Moreover, the digestion methods of TME have a significant impact on ecosystems. Sample preparation is an important step of any analytical procedure. In fact, defining the levels of TME in vegetal tissues requires various steps: drying samples, crushing, extraction, and dosage. The use of chemical extraction solutions can be put into question. Other than their lack of specificity, they are susceptible to provoking the redistribution and/or re-fixation of a part of the metallic ions between the various vegetal components. Our study aims to test the procedures of extraction that are specific for the metals Cu, Zn, Fe, Ca, Cr and Ba. Our results show an outstanding difference in the levels of TME derived from the same vegetal sample, according to the various techniques of extraction. In fact, cold extraction by nitric acid diluted at 10% is the most efficient way to put the ions of Cu, Zn, Fe and Ca into a solution. Meanwhile, the use of heated extraction using different acid digestion approaches is the most efficient for Cr and Ba solubilization from Atriplex portulacoides, Arthrocnemum indicum, Olea europaea BCR-62, Ulva lactuca and Ulva lactuca BCR-279.

Trace metal element (TME) pollution is a major threat to plants, animals and humans. Agricultural products contaminated with metals may pose health risks for people; therefore, international standards have been established by the FAO/WHO to ensure food safety as well as the possibility of crop production in contaminated soils. This study aimed to assess the accumulating potential of aluminum and barium in the roots, shoots and fruits of Abelmoschus esculentus L., and their effect on growth and mineral nutrition. The content of proline and some secondary metabolites was also evaluated. After treating okra plants with aluminum/barium (0, 100, 200, 400 and 600 µM) for 45 days, the results showed that Al stimulated the dry biomass production, whereas Ba negatively affected the growth and the fructification yield. The okra plants retained both elements and exhibited a preferential accumulation in the roots following the sequence: roots > shoots > fruits, which is interesting for phytostabilization purposes. Al or Ba exposure induced a decline in mineral uptake (K, Ca, Mg, Zn and Fe), especially in roots and shoots. In order to cope with the stress conditions, the okra plants enhanced their proline and total phenol amounts, offering better adaptability to stress.