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3.
Artigo em Inglês | MEDLINE | ID: mdl-33799620

RESUMO

The aim of this study was to identify the differences in body composition and physical fitness between children who played table tennis regularly during a two-year period compared to physically active children who were not engaged in a regular activity. Three hundred seventy-four children aged 10 to 11 years were divided into two groups: table tennis players (n = 109 boys and 73 girls) and physically active group (n = 88 boys and 104 girls). Anthropometric analysis included body mass index, skinfolds, perimeters and bone diameters. Somatotype and body composition were determined according to age-specific equations. Physical fitness assessment included hand grip dynamometry (strength), sit-and-reach test (range of movement) and maximal multistage 20 m shuttle run test (cardiovascular fitness). The result show that children who regularly played table tennis had greater bone development and superior physical fitness compared to those who were physically active but not engaged in a regular physical activity. This is the largest study to date presenting data about the potential of table tennis to benefit health in children. These results constitute an important first step in clarifying the effectiveness of table tennis as a health-promotion strategy to encourage children to undertake regular physical activity and limit sedentary behavior.


Assuntos
Tênis , Composição Corporal , Criança , Exercício Físico , Feminino , Força da Mão , Humanos , Masculino , Aptidão Física
4.
Artigo em Inglês | MEDLINE | ID: mdl-33803383

RESUMO

Several anthropometric and performance parameters related to aerobic metabolism are associated with performance in endurance runners and are modified according to the training performed. The objective of this study was to investigate the ergospirometric and body composition changes in endurance runners during a sports season in relation to their training. Twenty highly trained men endurance runners performed an incremental test until exhaustion (initial, and at 3, 6, and 9 months) on a treadmill to determine maximal oxygen consumption (VO2 max), second ventilatory threshold (VT2), and their associated running speeds. Skinfolds, perimeters, and weights were measured. No changes were obtained in VO2 max or VT2 during the study, although their associated running speeds increased (p < 0.05) after 3 months of the study. Decreases in fat mass (p < 0.05) and muscle mass (p < 0.05) were observed at the end of the season (9 months). Changes occurred in the different skinfolds according to the characteristics of the training performed during the season. In conclusion, vVO2 max and vVT2 increase with a greater volume of kilometres trained and can be adversely affected by loss of muscle mass.


Assuntos
Adaptação Fisiológica , Corrida , Atletas , Humanos , Masculino , Consumo de Oxigênio , Resistência Física , Estações do Ano
6.
Artigo em Inglês | MEDLINE | ID: mdl-33922289

RESUMO

The health benefits of sauna baths are attracting ever-increasing interest. Therefore, the purpose of this study was to evaluate the effects of 12 high-temperature (100 °C) sauna baths on body composition of 23 healthy young men, divided into a control group (CG) and a sauna group (SG). Both groups were initially evaluated by dual-energy X-ray absorptiometry (DXA), after which the SG experienced 12 sessions of sauna baths at high temperatures (100 °C). Initial measurements were carried out after the sauna sessions and after two weeks of decay in both groups. The muscle mass of the right leg (pre vs. decay: 9.50 (5.59) vs. 10.52 (5.15); p < 0.05; Δ 1.07%), bone mineral density (pre vs. post: 1.221 (0.35) vs. 1.315 (0.45); p < 0.05; Δ 7.7%) and bone mineral content (pre vs. post: 0.470 (0.21) vs. 0.499 (0.22); p < 0.05; Δ 6.17%) of the left leg increased in the SG after the sauna baths. It seems that exposure to heat at high temperatures could produce improvements in bone and muscle mass.


Assuntos
Banho a Vapor , Banhos , Pressão Sanguínea , Composição Corporal , Temperatura Corporal , Frequência Cardíaca , Temperatura Alta , Humanos , Masculino , Temperatura
7.
ACS Appl Mater Interfaces ; 13(19): 23260-23267, 2021 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-33957756

RESUMO

Molecular p-type electrical dopants have been proven useful to fine-tune the optoelectronic properties of bulk organic semiconductors and their interfaces. Here, the volume in polymer films and its role in solution-based electrical p-type doping using phosphomolybdic acid (PMA) are studied. The polymer film volume was controlled using two approaches. One is based on heating both the PMA solution and the film prior to immersion. The second is based on coating the polymer film with a liquid blend that contains the PMA solution and a swelling solvent. 31P NMR and FTIR experiments indicate that the Keggin structure appears to be preserved throughout the doping process. Results show that increasing the polymer volume facilitates the infiltration of the PMA Keggin structure, which results in an increased electrical p-type doping level.

8.
Artigo em Inglês | MEDLINE | ID: mdl-32806586

RESUMO

The aim of this study was to determine the possible changes in plasma of several hormones such as Luteinizing Hormone, Testosterone, Cortisol and Insulin in endurance runners during the sports season. Twenty-one high-level male endurance runners (22 ± 3.2 years, 1.77 ± 0.05 m) participated in the study. Basal plasma hormones were measured at four moments during the season (initial, 3, 6 and 9 months), and were analyzed using ELISA (enzyme-linked immunosorbent assay). Testosterone and Luteinizing Hormone (LH) suffered very significant decreases (p < 0.01) at 3 months compared with the beginning and an increase (p < 0.05) at 6 and 9 months compared with 3 months. Insulin level was significantly lower (p < 0.05) at 3, 6 and 9 months compared with the initial test. Insulin and cortisol were associated inversely (r = 0.363; ß = -0.577; p = 0.017) and positively (r = 0.202; ß = 0.310; p = 0.043), respectively, with the amount of km per week performed by the runners. There was a significant association between km covered at a higher intensity than the anaerobic threshold and I (r = 0.580; ß = -0.442; p = 0.000). Our findings indicate that testosterone, LH and insulin were more sensitive to changes in training volume and intensity than cortisol in high-level endurance runners. Basal testosterone and LH concentrations decrease in athletes who perform a high volume of aerobic km in situations of low energy availability.


Assuntos
Atletas , Resistência Física , Adulto , Humanos , Hidrocortisona/metabolismo , Hormônio Luteinizante/metabolismo , Masculino , Estações do Ano , Testosterona/metabolismo , Adulto Jovem
9.
Artigo em Inglês | MEDLINE | ID: mdl-32916939

RESUMO

The aim of this study was to determine the possible correlations between essential and toxic trace elements of plasma with several anthropometric and body composition parameters and performance in endurance runners. Sixty-five high-level middle and long-distance runners (21 ± 3 years; 1.77 ± 0.05 m; 64.97 ± 7.36 kg; VO2 max. 67.55 ± 4.11 mL/min/kg) participated in the present study. Abdominal, subscapular, iliac crest, triceps, front thigh and medial calf skinfold thicknesses and an incremental test until exhaustion were recorded. Body, fat, muscle and bone mass were estimated. Plasma trace elements were analyzed with inductively coupled plasma mass spectrometry (ICP-MS). Correlations and simple linear regression were used to assess the relationship between trace elements and several variables. Different skinfolds, fat mass, muscle mass and bone mass correlated positively and negatively with trace elements such as copper, manganese, selenium, vanadium, zinc, lithium, rubidium, strontium, arsenic, beryllium and lead. Lithium was related with performance. In conclusion, endurance training causes changes in the body concentrations of several trace elements that trigger modifications in body composition that may be interesting, if confirmed in the future, for the control of metabolic diseases such as obesity.


Assuntos
Corrida , Selênio , Oligoelementos , Composição Corporal , Humanos , Resistência Física , Corrida/fisiologia , Dobras Cutâneas , Adulto Jovem , Zinco
10.
Artigo em Inglês | MEDLINE | ID: mdl-33348799

RESUMO

Several essential trace minerals play an important role in the endocrine system; however, toxic trace minerals have a disruptive effect. The aim of this research was to determine basal concentrations and the possible correlations between trace minerals in plasma and several plasma hormones in runners. Sixty high-level male endurance runners (21 ± 3 years; 1.77 ± 0.05 m; 64.97 ± 7.36 kg) participated in the present study. Plasma hormones were analyzed using an enzyme-linked immunosorbent assay (ELISA) and plasma trace minerals were analyzed with inductively coupled plasma mass spectrometry (ICP-MS). Correlations and simple linear regression were used to assess the association between trace minerals and hormones. Plasma testosterone concentrations were inversely correlated with manganese (r = -0.543; ß = -0.410; p < 0.01), selenium (r = -0.292; ß = -0.024; p < 0.05), vanadium (r = -0.406; ß = -1.278; p < 0.01), arsenic (r = -0.336; ß = -0.142; p < 0.05), and lead (r = -0.385; ß = -0.418; p < 0.01). Plasma luteinizing hormone (LH) levels were positively correlated with arsenic (r = 0.298; ß = 0.327; p < 0.05) and cesium (r = 0.305; ß = 2.272; p < 0.05), and negatively correlated with vanadium (r = -0.303; ß = -2.467; p < 0.05). Moreover, cortisol concentrations showed significant positive correlations with cadmium (r = 0.291; ß = 209.01; p < 0.05). Finally, insulin concentrations were inversely related to vanadium (r = -0.359; ß = -3.982; p < 0.05). In conclusion, endurance runners living in areas with high environmental levels of toxic minerals should check their concentrations of anabolic hormones.


Assuntos
Hormônios , Minerais , Oligoelementos , Arsênio/sangue , Cádmio/sangue , Ensaio de Imunoadsorção Enzimática , Hormônios/sangue , Humanos , Masculino , Manganês/sangue , Espectrometria de Massas , Minerais/sangue , Selênio/sangue , Oligoelementos/sangue
11.
Artigo em Inglês | MEDLINE | ID: mdl-32967151

RESUMO

This study aimed to analyse the effects of Tetraselmis chuii (TC) microalgae supplementation during thirty days on ergospirometric, haematological and biochemical parameters in amateur soccer players. Thirty-two amateur soccer players divided into a control group (CG; n = 16; 22.36 ± 1.36 years; 68.36 ± 3.53 kg) and a supplemented group (SG; n = 16; 22.23 ± 2.19 years; 69.30 ± 5.56 kg) participated in the double-blind study. SG ingested 200 mg of the TC per day, while CG ingested 200 mg per day of lactose powder. Supplementation was carried out for thirty days. The participants performed a maximal treadmill test until exhaustion. The ergospirometric values at different ventilatory thresholds and haematological values were obtained after the test. Heart rate decreased after supplementation with TC (p < 0.05). Oxygen pulse, relative and absolute maximum oxygen consumption increased in SG (pre vs. post; 19.04 ± 2.53 vs. 22.08 ± 2.25; 53.56 ± 3.26 vs. 56.74 ± 3.43; 3.72 ± 0.35 vs. 3.99 ± 0.25; p < 0.05). Haemoglobin and mean corpuscular haemoglobin increased in SG (pre vs. post; 15.12 ± 0.87 vs. 16.58 ± 0.74 p < 0.01; 28.03 ± 1.57 vs. 30.82 ± 1.21; p < 0.05). On the other hand, haematocrit and mean platelet volume decreased in SG (p < 0.05). TC supplementation elicited improvements in ergospirometric and haematological values in amateur soccer players. TC supplementation could be valuable for improving performance in amateur athletes.


Assuntos
Desempenho Atlético , Suplementos Nutricionais , Microalgas , Futebol , Atletas , Método Duplo-Cego , Humanos
12.
Science ; 370(6517): 698-701, 2020 11 06.
Artigo em Inglês | MEDLINE | ID: mdl-33154137

RESUMO

Silicon photodiodes are the foundation of light-detection technology; yet their rigid structure and limited area scaling at low cost hamper their use in several emerging applications. A detailed methodology for the characterization of organic photodiodes based on polymeric bulk heterojunctions reveals the influence that charge-collecting electrodes have on the electronic noise at low frequency. The performance of optimized organic photodiodes is found to rival that of low-noise silicon photodiodes in all metrics within the visible spectral range, except response time, which is still video-rate compatible. Solution-processed organic photodiodes offer several design opportunities exemplified in a biometric monitoring application that uses ring-shaped, large-area, flexible, organic photodiodes with silicon-level performance.

13.
Rev. med. interna Guatem ; 19(1): 32-39, ene-abr. 2015. tab
Artigo em Espanhol | LILACS | ID: biblio-982106

RESUMO

En la actualidad hay una creciente aumento de diabetes mellitus tipo II y casos de mujeres en edad reproductiva, hay ciertos elementos a tomar en cuenta para abordar la consejería en la preconcepción. El artículo toca esos elementos a tomar en cuenta para ese tema para llevar a un felíz término el embarazo en dichos casos con un adecuado control.


Assuntos
Humanos , Feminino , Gravidez , Complicações na Gravidez , Diabetes Gestacional/diagnóstico , Diabetes Gestacional/prevenção & controle , Complicações do Diabetes/diagnóstico , Insulina/uso terapêutico
15.
La Paz; FIA; 1996. 163 p. ilus.(Producción Agropecuaria, 1).
Monografia em Espanhol | LILACS | ID: lil-250921

RESUMO

El presente documento es por el interés del estudio que radica en la necesidad de conocer la flora medicinal de la zona, para de esta manera poder sentar las bases para estudios fitoquímicos de la riqueza medicinal, y determinar con exactitud el potencial farmacológico que están empleando. La investigación nos proporciona una descripción botánica de las especies colectadas y preparación del correspondiente herbario de plantas medicinales utilizadas por los Isoseños Guaranies, que se encuentra en custodia del Herbario Nacional de Bolivia de la Universidad Mayor de San Andrés. Al mismo tiempo se muestra resultados de los análisis fitoquímico preliminar de las especies para establecer la presencia de probables metabolitos secundarios. (alcaloides, terpenoides-esteroides, compuestos fenólicos y flavonoides).Finalmente se llego a determinar algunas relaciones entre las enfermedades más comunes en la zona según la medicina académica, con las aplicaciones de las plantas medicinales reportadas


Assuntos
Plantas Medicinais/classificação , Bolívia , Botânica/classificação
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