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1.
Eur J Sport Sci ; 21(6): 861-870, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32633208

RESUMO

This study aimed to assess energy availability (EA), alongside possible risk factors of reduced or low EA of professional female soccer players during a competitive season. Thirteen players (age: 23.7 ± 3.4 y, stature: 1.69 ± 0.08 m, body mass: 63.7 ± 7.0 kg) engaged in a 5-day (two rest days, one light training, heavy training and match day) monitoring period. Energy intake (EI) and expenditure during exercise (EEE) were measured. EA was calculated and categorised as optimal, reduced or low (>45, 30-45, <30 kcal·kg FFM-1·day-1, respectively). Relationships between EA and bone mineral density, resting metabolic rate (RMR), plasma micronutrient status, biochemical markers and survey data were assessed. EA was optimal for 15%, reduced for 62% and low for 23% of players. Higher EA was observed on rest days compared to others (P<0.05). EA was higher for the light compared to the heavy training day (P<0.001). EEE differed significantly between days (P<0.05). EI (2124 ± 444 kcal), carbohydrate (3.31 ± 0.64 g·kg·day-1) and protein (1.83 ± 0.41 g·kg·day-1) intake remained similar (P>0.05). Survey data revealed 23% scored ≥8 on the Low Energy Availability in Females Questionnaire and met criteria for low RMR (ratio <0.90). Relationships between EA and risk factors were inconclusive. Most players displayed reduced EA and did not alter EI or carbohydrate intake according to training or match demands. Although cases of low EA were identified, further work is needed to investigate possible long-term effects and risk factors of low and reduced EA separately to inform player recommendations.


Assuntos
Ingestão de Energia , Metabolismo Energético , Condicionamento Físico Humano/fisiologia , Futebol/fisiologia , Adulto , Metabolismo Basal , Biomarcadores/sangue , Composição Corporal , Densidade Óssea , Carboidratos da Dieta/administração & dosagem , Comportamento Alimentar , Feminino , Humanos , Micronutrientes/sangue , Fatores de Risco , Inquéritos e Questionários , Adulto Jovem
2.
Sports Med ; 48(Suppl 1): 3-16, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29368183

RESUMO

The last decade has seen a dramatic increase in general interest in and research into vitamin D, with many athletes now taking vitamin D supplements as part of their everyday dietary regimen. The most recognized role of vitamin D is its regulation of calcium homeostasis; there is a strong relationship between vitamin D and bone health in non-athletic individuals. In contrast, data have consistently failed to demonstrate any relationship between serum 25[OH]D and bone health, which may in part be due to the osteogenic stimulus of exercise. Vitamin D may interact with extra-skeletal tissues such as muscle and the immune system to modulate recovery from damaging exercise and infection risk. Given that many athletes now engage in supplementation, often consuming extreme doses of vitamin D, it is important to assess whether excessive vitamin D can be detrimental to health. It has been argued that toxic effects only occur when serum 25[OH]D concentrations are greater than 180 nmol·l-1, but data from our laboratory have suggested high-dose supplementation could be problematic. Finally, there is a paradoxical relationship between serum 25[OH]D concentration, ethnicity, and markers of bone health: Black athletes often present with low serum 25[OH]D without physiological consequences. One explanation for this could be genetic differences in vitamin D binding protein due to ethnicity, resulting in greater concentrations of bioavailable (or free) vitamin D in some ethnic groups. In the absence of any pathology, screening may be unnecessary and could result in incorrect supplementation. Data must now be re-examined, taking into consideration bioavailable or "free" vitamin D in ethnically diverse groups to enable new thresholds and target concentrations to be established; perhaps, for now, it is time to "set vitamin D free".


Assuntos
Atletas , Suplementos Nutricionais , Vitamina D/administração & dosagem , Vitaminas/administração & dosagem , Humanos , Deficiência de Vitamina D
3.
Br J Sports Med ; 52(8): 522-526, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28798036

RESUMO

BACKGROUND: The association between bone mineral density (BMD) and serum25-hydroxyvitamin D (25(OH)D) concentration is weak, particularly in certain races (eg, BlackAfrican vs Caucasian) and in athletic populations. We aimed to examine if bioavailable vitamin D rather than serum 25(OH)D was related to markers of bone health within a racially diverse athletic population. METHODS: In 604 male athletes (Arab (n=327), Asian (n=48), Black (n=108), Caucasian (n=53) and Hispanic (n=68)), we measured total 25(OH)D, vitamin D-binding protein and BMD by DXA. Bioavailable vitamin D was calculated using the free hormone hypothesis. RESULTS: From 604 athletes, 21.5% (n=130) demonstrated severe 25(OH)D deficiency, 37.1% (n=224) deficiency, 26% (n=157) insufficiency and 15.4% (n=93) sufficiency. Serum 25(OH)D concentrations were not associated with BMD at any site. After adjusting for age and race, bioavailable vitamin D was associated with BMD (spine, neck and hip). Mean serum vitamin D binding protein concentrations were not associated with 25(OH)D concentrations (p=0.392). CONCLUSION: Regardless of age or race, bioavailable vitamin D and not serum 25(OH)D was associated with BMD in a racially diverse athletic population. If vitamin D screening is warranted, clinicians should use appropriate assays to calculate vitamin D binding protein and bioavailable vitamin D levels concentrations than serum 25(OH)D. In turn, prophylactic vitamin D supplementation to 'correct' insufficient athletes should not be based on serum 25(OH)D measures.


Assuntos
Densidade Óssea , Vitamina D/sangue , Absorciometria de Fóton , Adolescente , Adulto , Atletas , Disponibilidade Biológica , Biomarcadores/sangue , Humanos , Masculino , Hormônio Paratireóideo/sangue , Proteína de Ligação a Vitamina D/sangue , Adulto Jovem
4.
Med Sci Sports Exerc ; 47(4): 782-8, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25058327

RESUMO

PURPOSE: Adequate vitamin D (25(OH)D) is required to maintain good bone health, yet many athletes are 25(OH)D deficient. This study sought to examine the relation between serum 25(OH)D and measures of bone health (bone mineral density (BMD) and T-score) in an ethnically diverse athletic population. METHODS: Nine hundred and fifty male athletes presented for precompetition medical assessment in our facility. An additional 436 individuals registered with a Qatari sporting federation (such as sailing, archery, shooting, bowling) but exercising <2 h·wk were used as control population. There were 30 Asian, 242 Black African, 235 Caucasian, 491 from Gulf Cooperation Countries, 336 Middle Eastern, and 52 Persian participants. All individuals undertook bone densitometry and body composition analysis by dual-energy x-ray absorptiometry and serum 25(OH)D evaluation. RESULTS: From 950 athletes, 17.5% demonstrated severe deficiency, 39.2% demonstrated deficiency, 24.5% demonstrated insufficiency, and 18.8% demonstrated sufficiency, compared with 436 controls, 25.9% of whom demonstrated severe deficiency, 46.3% demonstrated deficiency, 19.0% demonstrated insufficiency, and 8.7% demonstrated sufficiency. No athlete presented with a T-score suggestive of osteoporosis (-2.5 SD) or osteopenia (-1.0 SD) at hip total. After adjustment for age, anthropometry, ethnicity, and athletic participation, there was no association between 25(OH)D and any BMD and T-score at any site within athletes. African and Caucasian athletes present with greater (P < 0.05) BMD and T-scores at the spine, neck, and hip total than those of Asian, Gulf Cooperation Countries, Middle Eastern, and Persian ethnicities. Athletes participating in high-impact sports present with higher measures (P < 0.05) of bone health than control participants regardless of 25(OH)D status. CONCLUSIONS: There is no association between 25(OH)D and BMD and T-score for any site within male athletes after adjusting for age, ethnicity, and sporting participation.


Assuntos
Densidade Óssea , Calcifediol/sangue , Esportes/fisiologia , Deficiência de Vitamina D/fisiopatologia , Absorciometria de Fóton , Adulto , Antropometria , Biomarcadores/sangue , Humanos , Estilo de Vida , Masculino , Luz Solar , Deficiência de Vitamina D/etnologia , Adulto Jovem
5.
Eur J Prev Cardiol ; 22(4): 535-42, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24398372

RESUMO

BACKGROUND: Vitamin D (25(OH)D) deficiency has associations with bowl/colon cancer, arthritis, diabetes, and cardiovascular disease. Many athletes are vitamin D deficient, yet no studies have examined the association between 25(OH)D status and cardiac structure and function in healthy athletes. DESIGN: A total of 506 national-level athletes [football (50%), handball (23%), volleyball (16%), and basketball (11%)] and 244 control participants presented for precompetition medical assessment. Controls were healthy individuals registered with a sporting federation undertaking <2 h of exercise per week. METHODS: All individuals undertook a physical examination, 12-lead electrocardiogram, echocardiogram, and serum 25(OH)D evaluation. RESULTS: From 506 athletes and 244 controls, 23 and 12.3% demonstrated 25(OH)D sufficiency (>30 ng/ml), 30 and 23.4% insufficiency (20-30 ng/ml), 37.2 and 48.8% deficiency (10-20 ng/ml), and 11 and 15.6% severe deficiency (<10 ng/ml). Severely 25(OH)D-deficient athletes present significantly (p < 0.05) smaller aortic root and left atria diameters, intraventricular septum diameter (IVSd), left ventricular diameter during diastole (LVIDd), left ventricular mass (LVM), left ventricular volume during diastole (LVvolD), and right atrial (RA) area than insufficient and sufficient athletes. Furthermore, following logarithmic transformation adjusting 25(OH)D for age, body surface area, ethnicity, and athletic participation, positive associations were observed between 25(OH)D and IVSd, LVIDd, posterior wall thickness during diastole, LVM, and LVvolD in athletes but not in the control participants. CONCLUSIONS: Severely 25(OH)D-deficient athletes present significantly smaller cardiac structural parameters than insufficient and sufficient athletes. Future research should investigate the precise mechanism(s) causing cardiac hypertrophy with increases in serum 25(OH)D in healthy athletes.


Assuntos
Atletas , Cardiomegalia Induzida por Exercícios , Coração/crescimento & desenvolvimento , Deficiência de Vitamina D/complicações , Vitamina D/análogos & derivados , Adulto , Biomarcadores , Estudos de Casos e Controles , Ecocardiografia , Eletrocardiografia , Coração/fisiopatologia , Humanos , Masculino , Tamanho do Órgão , Fatores de Risco , Índice de Gravidade de Doença , Vitamina D/sangue , Deficiência de Vitamina D/sangue , Deficiência de Vitamina D/diagnóstico , Adulto Jovem
6.
Respir Med ; 108(12): 1794-800, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25294691

RESUMO

BACKGROUND: Conflicting data exists on the effectiveness of integrated programs in reducing recurrent exacerbations and hospitalizations in patients with Asthma and chronic obstructive lung disease (COPD). We developed a Pulmonologist-led Chronic Lung Disease Program (CLDP) for patients with severe asthma and COPD and analyzed its impact on healthcare utilization and predictors of its effectiveness. METHODS: CLDP elements included clinical evaluation, onsite pulmonary function testing, health education, and self-management action plan along with close scheduled and on-demand follow-up. Patients with ≥2 asthma or COPD exacerbations requiring emergency room visit or hospitalization within the prior year were enrolled, and followed for respiratory related ER visits (RER) and hospitalizations (RHA) over the year (357 ± 43 days) after CLDP interventions. RESULTS: A total of 106 patients were enrolled, and 104 patients were subject to analyses. During the year of follow-up after CLDP enrollment, there was a significant decrease in mean RER (0.56 ± 1.48 versus 2.62 ± 2.81, p < 0.0001), mean RHA (0.39 ± 0.08 versus 1.1 ± 1.62, p < 0.0001), and 30 day rehospitalizations (0.05 ± 0.02 versus 0.28 ± 0.07, p < 0.0001). Reduction of healthcare utilization was strongly associated with GERD and sinusitis therapy, and was independent of pulmonary rehabilitation. Direct variable cost analyses estimated annual savings at $1.17 million. Multivariate logistic regression analysis revealed lack of spirometry utilization as an independent risk factor for severe exacerbations. CONCLUSIONS: A Pulmonologist-led disease management program integrating key elements of care is cost effective and significantly decreases severe exacerbations. Integrated programs should be encouraged for care of frequent exacerbators of asthma and COPD.


Assuntos
Asma/terapia , Prestação Integrada de Cuidados de Saúde/métodos , Gerenciamento Clínico , Doença Pulmonar Obstrutiva Crônica/terapia , Adulto , Idoso , Asma/economia , Asma/fisiopatologia , California , Prestação Integrada de Cuidados de Saúde/economia , Serviço Hospitalar de Emergência/estatística & dados numéricos , Feminino , Volume Expiratório Forçado/fisiologia , Custos de Cuidados de Saúde/estatística & dados numéricos , Hospitalização/estatística & dados numéricos , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Avaliação de Programas e Projetos de Saúde , Doença Pulmonar Obstrutiva Crônica/economia , Doença Pulmonar Obstrutiva Crônica/fisiopatologia , Autocuidado/economia , Autocuidado/métodos , Resultado do Tratamento
7.
Plant Biotechnol J ; 11(6): 702-8, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23521804

RESUMO

Prunus necrotic ringspot virus (PNRSV) is a major pollen-disseminated ilarvirus that adversely affects many Prunus species. In this study, an RNA interference (RNAi) vector pART27-PNRSV containing an inverted repeat (IR) region of PNRSV was transformed into two hybrid (triploid) cherry rootstocks, 'Gisela 6' (GI 148-1) and 'Gisela 7'(GI 148-8)', which are tolerant and sensitive, respectively, to PNRSV infection. One year after inoculation with PNRSV plus Prune Dwarf Virus, nontransgenic 'Gisela 6' exhibited no symptoms but a significant PNRSV titre, while the transgenic 'Gisela 6' had no symptoms and minimal PNRSV titre. The nontransgenic 'Gisela 7' trees died, while the transgenic 'Gisela 7' trees survived. These results demonstrate the RNAi strategy is useful for developing viral resistance in fruit rootstocks, and such transgenic rootstocks may have potential to enhance production of standard, nongenetically modified fruit varieties while avoiding concerns about transgene flow and exogenous protein production that are inherent for transformed fruiting genotypes.


Assuntos
Resistência à Doença/genética , Engenharia Genética , Ilarvirus/fisiologia , Doenças das Plantas/virologia , Raízes de Plantas/genética , Prunus/virologia , Interferência de RNA , DNA Bacteriano/genética , Ensaio de Imunoadsorção Enzimática , Doenças das Plantas/genética , Raízes de Plantas/virologia , Plantas Geneticamente Modificadas , Prunus/genética , Regeneração , Transformação Genética
8.
Virus Res ; 122(1-2): 171-4, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-16965831

RESUMO

Viral transgenes designed to provide resistance to specific plant viruses frequently consist of the coat protein gene and a contiguous 3' untranslated region (3'UTR) of viral origin. In many RNA viruses the viral 3'UTR establishes a recognition and initiation site for viral RNA replication. Thus the transgenic transcript may contain a functional virus replication site. Experiments were designed to determine if a challenging virus would recognize this replication site on a nuclear derived transcript and synthesize the complementary RNA. These data demonstrate that upon infection by a virus that recognizes the viral replication site, a full-length complement of the transgenic transcript is produced. In these experiments the replication complex of Brome Mosaic bromovirus recognized the transgenic transcript derived from a Cowpea Chlorotic Mottle bromovirus transgene. The resulting RNA may contribute to RNA recombination events.


Assuntos
Bromovirus/genética , Plantas Geneticamente Modificadas/virologia , RNA Complementar/biossíntese , RNA Viral/biossíntese , Bromovirus/fisiologia , Eletroforese em Gel de Ágar , Recombinação Genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Replicação Viral
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