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1.
Nutrients ; 13(11)2021 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-34836033

RESUMO

BACKGROUND: EPA and DHA n-3 FA play crucial roles in both neurological and cardiovascular health and high dietary intakes along with supplementation suggest potential neuroprotection and concussion recovery support. Rugby athletes have a high risk of repetitive sub-concussive head impacts which may lead to long-term neurological deficits, but there is a lack of research looking into n-3 FA status in rugby players. We examined the dietary n-3 FA intake through a FFQ and n-3 FA status by measuring the percentage of n-3 FA and O3I in elite Canadian Rugby 7s players to show distribution across O3I risk zones; high risk, <4%; intermediate risk, 4 to 8%; and low risk, >8%. METHODS: n-3 FA profile and dietary intake as per FFQ were collected at the beginning of the 2017-2018 Rugby 7s season in male (n = 19; 24.84 ± 2.32 years; 95.23 ± 6.93 kg) and female (n = 15; 23.45 ± 3.10 years; 71.21 ± 5.79 kg) athletes. RESULTS: O3I averaged 4.54% ± 1.77, with female athlete scores slightly higher, and higher O3I scores in supplemented athletes (4.82% vs. 3.94%, p = 0.183), with a greater proportion of non-supplemented athletes in the high-risk category (45.5% vs. 39.1%). Dietary intake in non-supplemented athletes did not meet daily dietary recommendations for ALA or EPA + DHA compared to supplemented athletes. CONCLUSIONS: Overall, despite supplementation, O3I score remained in the high-risk category in a proportion of athletes who met recommended n-3 FA dietary intakes, and non-supplemented athletes had a higher proportion of O3I scores in the high-risk category, suggesting that dietary intake alone may not be enough and athletes may require additional dietary and n-3 FA supplementation to reduce neurological and cardiovascular risk.


Assuntos
Atletas/estatística & dados numéricos , Dieta/estatística & dados numéricos , Suplementos Nutricionais , Ácidos Graxos Ômega-3/análise , Rugby , Canadá , Inquéritos sobre Dietas , Ingestão de Alimentos , Feminino , Humanos , Masculino , Estado Nutricional , Recomendações Nutricionais , Adulto Jovem
2.
J Vis Exp ; (148)2019 06 30.
Artigo em Inglês | MEDLINE | ID: mdl-31305526

RESUMO

This protocol demonstrates a method for electrochemical roughening of thin-film platinum electrodes without preferential dissolution at grain boundaries of the metal. Using this method, a crack free, thin-film macroelectrode surface with up to 40 times increase in active surface area was obtained. The roughening is easy to do in a standard electrochemical characterization laboratory and incudes the application of voltage pulses followed by extended application of a reductive voltage in a perchloric acid solution. The protocol includes the chemical and electrochemical preparation of both a macroscale (1.2 mm diameter) and microscale (20 µm diameter) platinum disc electrode surface, roughening the electrode surface and characterizing the effects of surface roughening on electrode active surface area. This electrochemical characterization includes cyclic voltammetry and impedance spectroscopy and is demonstrated for both the macroelectrodes and the microelectrodes. Roughening increases electrode active surface area, decreases electrode impedance, increases platinum charge injection limits to those of titanium nitride electrodes of same geometry and improves substrates for adhesion of electrochemically deposited films.


Assuntos
Técnicas Eletroquímicas , Platina , Impedância Elétrica , Eletrodos , Propriedades de Superfície
3.
J Strength Cond Res ; 33(1): 152-158, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30363035

RESUMO

Gilmore, SL, Brilla, LR, Suprak, DN, Chalmers, GR, and Dahlquist, DT. Effect of a high-intensity isometric potentiating warm-up on bat velocity. J Strength Cond Res 33(1): 152-158, 2019-This study examined the acute effect of a high-intensity isometric potentiating warm-up on subsequent maximal horizontal bat velocity in experienced female softball players (n = 28). The isometric potentiating warm-up consisted of 3 sets of 5-second maximal voluntary contractions held in the early swing phase position, pulling against an immovable device. As one of the simplest methods to use the postactivation potentiation (PAP) stimulus, the warm-up was designed to acutely enhance muscle performance by inducing PAP. Because optimal recovery duration after a potentiating warm-up can be highly variable, swing trials were conducted at predetermined rest intervals (1, 2, 4, 6, 8, 10, and 12 minutes) to identify the recovery time that may have allowed for maximal possible benefits. Bat velocity was measured immediately before bat-ball impact using MaxTRAQ motion analysis software. The results showed that maximal horizontal bat velocity was significantly enhanced 6 minutes after the isometric warm-up protocol (+1.27 m·s, +2.84 mph, +4.93%; p < 0.05). In experienced female softball athletes, a specific isometric warm-up may acutely enhance maximal horizontal bat velocity.


Assuntos
Desempenho Atlético/fisiologia , Beisebol/fisiologia , Treinamento Intervalado de Alta Intensidade , Exercício de Aquecimento , Adolescente , Adulto , Atletas , Feminino , Humanos , Contração Isométrica , Músculo Esquelético/fisiologia , Adulto Jovem
4.
Appl Physiol Nutr Metab ; 42(10): 1036-1043, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28605609

RESUMO

Iron deficiency has ergolytic effects on athletic performance. Exercise-induced inflammation impedes iron absorption in the digestive tract by upregulating the expression of the iron regulatory protein, hepcidin. Limited research indicates the potential of specific macro- and micronutrients on blunting exercise-induced hepcidin. Therefore, we investigated the effects of postexercise supplementation with protein and carbohydrate (CHO) and vitamins D3 and K2 on the postexercise hepcidin response. Ten highly trained male cyclists (age: 26.9 ± 6.4 years; maximal oxygen uptake: 67.4 ± 4.4 mL·kg-1·min-1 completed 4 cycling sessions in a randomized, placebo-controlled, single-blinded, triple-crossover study. Experimental days consisted of an 8-min warm-up at 50% power output at maximal oxygen uptake, followed by 8 × 3-min intervals at 85% power output at maximal oxygen uptake with 1.5 min at 60% power output at maximal oxygen uptake between each interval. Blood samples were collected pre- and postexercise, and at 3 h postexercise. Three different drinks consisting of CHO (75 g) and protein (25 g) with (VPRO) or without (PRO) vitamins D3 (5000 IU) and K2 (1000 µg), or a zero-calorie control drink (PLA) were consumed immediately after the postexercise blood sample. Results showed that the postexercise drinks had no significant (p ≥ 0.05) effect on any biomarker measured. There was a significant (p < 0.05) increase in hepcidin and interleukin-6 following intense cycling intervals in the participants. Hepcidin increased significantly (p < 0.05) from baseline (nmol·L-1: 9.94 ± 8.93, 14.18 ± 14.90, 10.44 ± 14.62) to 3 h postexercise (nmol·L-1: 22.27 ± 13.41, 25.44 ± 11.91, 22.57 ± 15.57) in VPRO, PRO, and PLA, respectively. Contrary to our hypothesis, the drink compositions used did not blunt the postexercise hepcidin response in highly trained athletes.


Assuntos
Atletas , Colecalciferol/administração & dosagem , Dieta , Carboidratos da Dieta/administração & dosagem , Proteínas Alimentares/administração & dosagem , Hepcidinas/sangue , Estado Nutricional , Resistência Física , Vitamina K 2/administração & dosagem , Administração Oral , Adulto , Bebidas , Ciclismo , Biomarcadores/sangue , Colúmbia Britânica , Estudos Cross-Over , Ferritinas/sangue , Hemoglobinas/metabolismo , Humanos , Interleucina-6/sangue , Ferro/sangue , Masculino , Consumo de Oxigênio , Método Simples-Cego , Fatores de Tempo , Adulto Jovem
5.
J Int Soc Sports Nutr ; 12: 33, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26288575

RESUMO

The purpose of this review is to examine vitamin D in the context of sport nutrition and its potential role in optimizing athletic performance. Vitamin D receptors (VDR) and vitamin D response elements (VDREs) are located in almost every tissue within the human body including skeletal muscle. The hormonally-active form of vitamin D, 1,25-dihydroxyvitamin D, has been shown to play critical roles in the human body and regulates over 900 gene variants. Based on the literature presented, it is plausible that vitamin D levels above the normal reference range (up to 100 nmol/L) might increase skeletal muscle function, decrease recovery time from training, increase both force and power production, and increase testosterone production, each of which could potentiate athletic performance. Therefore, maintaining higher levels of vitamin D could prove beneficial for athletic performance. Despite this situation, large portions of athletic populations are vitamin D deficient. Currently, the research is inconclusive with regards to the optimal intake of vitamin D, the specific forms of vitamin D one should ingest, and the distinct nutrient-nutrient interactions of vitamin D with vitamin K that affect arterial calcification and hypervitaminosis. Furthermore, it is possible that dosages exceeding the recommendations for vitamin D (i.e. dosages up to 4000-5000 IU/day), in combination with 50 to 1000 mcg/day of vitamin K1 and K2 could aid athletic performance. This review will investigate these topics, and specifically their relevance to athletic performance.


Assuntos
Desempenho Atlético , Substâncias para Melhoria do Desempenho/farmacologia , Vitamina D/farmacologia , Suplementos Nutricionais , Relação Dose-Resposta a Droga , Humanos , Força Muscular/efeitos dos fármacos , Músculo Esquelético/efeitos dos fármacos , Substâncias para Melhoria do Desempenho/sangue , Fenômenos Fisiológicos da Nutrição Esportiva , Vitamina D/sangue , Deficiência de Vitamina D/tratamento farmacológico , Vitamina K/farmacologia
6.
J Athl Train ; 50(8): 785-91, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26090707

RESUMO

CONTEXT: Joint position sense (JPS) is a key neuromuscular factor for developing and maintaining control of muscles around a joint. It is important when performing specialized tasks, especially at the shoulder. No researchers have studied how Kinesio Tape (KT) application affects JPS. OBJECTIVE: To investigate the effects of KT application and no tape on shoulder JPS at increasing shoulder elevations in athletes. DESIGN: Cross-sectional study. SETTING: University laboratory. PATIENTS OR OTHER PARTICIPANTS: A total of 27 healthy athletes who did not participate in overhead sports (age = 20.44 ± 1.05 years, height = 175.02 ± 11.67 cm, mass = 70.74 ± 9.65 kg) with no previous pathologic shoulder conditions volunteered for the study. All participants were from 1 university. INTERVENTION(S): Shoulder JPS was assessed at increasing elevations with and without KT application. Participants attempted to actively replicate 3 target positions with and without the KT and without visual guidance. MAIN OUTCOME MEASURE(S): We examined absolute and variable repositioning errors at increasing shoulder-elevation levels with and without KT application. RESULTS: Data revealed an interaction between tape and position for absolute error (F2,52 = 4.07, P = .02); simple effects revealed an increase in error, with KT demonstrating a 2.65° increase in error at 90° of elevation compared with no tape (t26 = 2.65, P = .01). The effect size was medium (ω(2) = .135). Variable error showed no interaction of tape and position (F2,52 = .709, P = .50). Further analysis of simple effects was not needed. However, we still calculated the effect size and observed small effect sizes for tape (ω(2) = .002), position (ω(2) = .072), and tape by position (ω(2) = .027). CONCLUSIONS: At 90° of elevation, shoulder JPS was impaired by the application of KT.


Assuntos
Fita Atlética , Propriocepção/fisiologia , Articulação do Ombro/fisiologia , Esportes/fisiologia , Fenômenos Biomecânicos/fisiologia , Estudos Transversais , Feminino , Voluntários Saudáveis , Humanos , Masculino , Músculo Esquelético/fisiologia , Adulto Jovem
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