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1.
Sports Health ; 16(5): 711-721, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38406865

RESUMO

BACKGROUND: Taurine (TAU) and caffeine (CAF), as common ergogenic aids, are known to affect exercise performance; however, the effects of their combined supplementation, particularly in high temperature and humidity environments, have not been studied. HYPOTHESIS: The combination of TAU and CAF will have a greater effect on endurance cycle performance and improve changes in physiological indicators during exercise compared with TAU or CAF supplementation alone and placebo. STUDY DESIGN: Single-blind crossover randomized controlled study. LEVEL OF EVIDENCE: Level 1. METHODS: Twelve university students majoring in physical education volunteered to receive 4 different supplement ingestions: (1) placebo (maltodextrin), (2) TAU, (3) CAF, (4) TAU + CAF. After a 7-day washout period, participants completed a time to exhaustion (TTE) test in the heat (35°C, 65% relative humidity). RESULTS: All experimental groups improved TTE compared with the placebo group. Peak and mean power of countermovement jump were significantly higher in the CAF group compared with the placebo group before the exhaustion exercise (P = 0.02, d = 1.2 and P = 0.04, d = 1.1, respectively). Blood lactate was significantly lower after the exhaustion test in the TAU group compared with the CAF (P < 0.01, d = 0.8) and TAU + CAF (P < 0.01, d = 0.7) groups. Core temperature in the TAU group was significantly reduced in the placebo group later in the exhaustion test (P < 0.01, d = 1.9). CONCLUSION: In high temperature and humidity environments, acute TAU, CAF, and combined supplementation all improved TTE and did not affect recovery from lower limb neuromuscular fatigue compared with placebo, with TAU having the best effect. Combined supplementation failed to exhibit superimposed performance. CLINICAL RELEVANCE: The results provide suggestions for the effects of TAU, CAF, and their combined intake on exercise performance in high temperature and humidity environments.


Assuntos
Desempenho Atlético , Cafeína , Estudos Cross-Over , Temperatura Alta , Umidade , Ácido Láctico , Resistência Física , Taurina , Humanos , Cafeína/administração & dosagem , Cafeína/farmacologia , Método Simples-Cego , Adulto Jovem , Masculino , Taurina/administração & dosagem , Resistência Física/efeitos dos fármacos , Resistência Física/fisiologia , Desempenho Atlético/fisiologia , Ácido Láctico/sangue , Ciclismo/fisiologia , Substâncias para Melhoria do Desempenho/administração & dosagem , Suplementos Nutricionais , Teste de Esforço
2.
Res Q Exerc Sport ; 95(3): 751-758, 2024 09.
Artigo em Inglês | MEDLINE | ID: mdl-38329497

RESUMO

Purpose: Exogenous melatonin has been proven to have beneficial effects on sleep. A good sleep quality promotes recovery and improves physical performance. In this sense, the present study aimed to explore the potential effect of nocturnal melatonin ingestion on psycho-cognitive and short-term maximal performances, in the following morning. Method: Twelve professional soccer players (22.9 ± 1.3 years, 1.80 ± 0.05 m, and 72.0 ± 8.8 kg) volunteered to perform two separate testing sessions after either nocturnal melatonin or placebo ingestion. The next morning, participants performed the following psycho-cognitive and physical tests: Hooper's index, reaction time, vigilance, handgrip strength (HG), squat jump (SJ), modified agility T-test (MAT) and Wingate anaerobic test (WanT). Rating of perceived exertion (RPE) and blood lactate [La] were recorded, respectively, immediately and 3 min after the WanT. Blood glucose [GL] was measured before and 3 min after WanT. Results: Compared with placebo, melatonin improved subjective sleep quality, short-term maximal performances (HG and SJ), reaction-time, as well as peak and mean WanT powers and decreased fatigue index and RPE scores. However, [La] and [GL] were not affected by melatonin ingestion. Conclusion: Nocturnal melatonin intake before sleep has beneficial effects on cognitive and physical performances the following day.


Assuntos
Desempenho Atlético , Força da Mão , Ácido Láctico , Melatonina , Tempo de Reação , Futebol , Humanos , Melatonina/administração & dosagem , Futebol/fisiologia , Desempenho Atlético/fisiologia , Adulto Jovem , Força da Mão/fisiologia , Masculino , Tempo de Reação/efeitos dos fármacos , Ácido Láctico/sangue , Qualidade do Sono , Método Duplo-Cego , Glicemia/metabolismo , Esforço Físico/fisiologia , Estudos Cross-Over , Teste de Esforço , Cognição/efeitos dos fármacos , Cognição/fisiologia
3.
Int J Sports Physiol Perform ; 19(5): 427-434, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38335952

RESUMO

INTRODUCTION: The acute and isolated ingestion of sodium bicarbonate (NaHCO3) and caffeine (CAF) improves performance and delays fatigue in high-intensity tasks. However, it remains to be elucidated if the coingestion of both dietary supplements stimulates a summative ergogenic effect. This study aimed to examine the effect of the acute coingestion of NaHCO3 and CAF on repeated-sprint performance. METHODS: Twenty-five trained participants (age: 23.3 [4.0] y; sex [female/male]: 12/13; body mass: 69.6 [12.5] kg) participated in a randomized, double-blind, placebo (PLA) -controlled, crossover study. Participants were assigned to 4 conditions: (1) NaHCO3 + CAF, (2) NaHCO3, (3) CAF, or (4) PLA. Thus, they ingested 0.3 g/kg of NaHCO3, 3 mg/kg of CAF, or PLA. Then, participants performed 4 Wingate tests (Wt), consisting of a 30-second all-out sprint against an individualized resisted load, interspersed by a 1.5-minute rest period between sprints. RESULTS: Peak (Wpeak) and mean (Wmean) power output revealed a supplement and sprint interaction effect (P = .009 and P = .049, respectively). Compared with PLA, NaHCO3 + CAF and NaHCO3 increased Wpeak performance in Wt 3 (3%, P = .021) and Wt 4 (4.5%, P = .047), while NaHCO3 supplementation increased mean power performance in Wt 3 (4.2%, P = .001). In Wt 1, CAF increased Wpeak (3.2%, P = .054) and reduced time to Wpeak (-8.5%; P = .008). Plasma lactate showed a supplement plus sprint interaction (P < .001) when NaHCO3 was compared with CAF (13%, P = .031) and PLA (23%, P = .021). CONCLUSION: To summarize, although the isolated ingestion of CAF and NaHCO3 improved repeated-sprint performance, the coingestion of both supplements did not stimulate a synergic ergogenic effect.


Assuntos
Desempenho Atlético , Cafeína , Estudos Cross-Over , Suplementos Nutricionais , Ácido Láctico , Substâncias para Melhoria do Desempenho , Corrida , Bicarbonato de Sódio , Humanos , Bicarbonato de Sódio/administração & dosagem , Bicarbonato de Sódio/farmacologia , Cafeína/administração & dosagem , Masculino , Feminino , Desempenho Atlético/fisiologia , Método Duplo-Cego , Adulto Jovem , Substâncias para Melhoria do Desempenho/administração & dosagem , Corrida/fisiologia , Ácido Láctico/sangue , Adulto , Teste de Esforço
4.
J Diet Suppl ; 20(5): 689-705, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-35758017

RESUMO

Sodium bicarbonate (NaHCO3) has been used as an ergogenic substance during high-intensity exercises. Therefore, the aim of the present study was to investigate the effects of NaHCO3 supplementation on external and internal load parameters during isokinetic exercise in trained subjects. Ten subjects were tested on two occasions: after ingesting 0.3 g.kg-1 of body mass of NaHCO3 or placebo. Maximum voluntary isometric contraction was performed before and after a dynamic protocol consisting of 10 series of 10 movements of flexion/extension of the knee extensors at 120° s-1 at an interval of 60 s between series. Outcomes considered were: peak torque (isokinetic dynamometry), blood lactate and creatine concentration (CK), analysis of perceptions of effort (OMNI scale), pain (visual analog scale) and recovery (scale raging 6 to 20). Performance was assessed using peak torque values. Muscle damage was assessed prior and 24 h post exercise. The subjective perceptions of effort, pain and recovery were assessed at different times and the internal load of the session was assessed 30 min post-effort. Although significant reductions in peak torque were noted both in isometric (NaHCO3:-29.11 ± 22.95%, Placebo: -23.51 ± 15.23%; p = 0.38) and isokinetic strength (NaHCO3:-23.0 ± 13.9%, Placebo:-19.6 ± 9.1%; p = 0.09), there was no effect of supplementation on performance (p > 0.05). The blood CK concentrations (NaHCO3: pre:225.3 ± 135.9 U/L, post: 418.4 ± 318.4 U/L; Placebo: pre:238 ± 94.03 U/L, post:486 ± 336.6 U/L) increased after protocol (p = 0.005), however, without differences between conditions. In conclusion, the NaHCO3 did not attribute benefits in performance or in parameters related to the internal load of exercise.


Assuntos
Suplementos Nutricionais , Músculo Esquelético , Bicarbonato de Sódio , Humanos , Estudos Cross-Over , Método Duplo-Cego , Músculo Esquelético/efeitos dos fármacos , Dor , Bicarbonato de Sódio/farmacologia , Creatina Quinase/sangue , Contração Isométrica , Ácido Láctico/sangue
5.
Sci Rep ; 12(1): 1825, 2022 02 03.
Artigo em Inglês | MEDLINE | ID: mdl-35115578

RESUMO

Vitamin D is necessary for musculoskeletal health, however, the supplementation of vitamin D above the sufficiency level does not bring additional bone mass density (BMD), unlike physical exercise which enhances the bone formatting process. Regular physical activity has been shown to upregulate VDR expression in muscles and to increase circulating vitamin D. Here we investigate whether a single bout of exercise might change 25(OH)D3 blood concentration and how it affects metabolic response to exercise. Twenty-six boys, 13.8 years old (SD ± 0.7) soccer players, participated in the study. The participants performed one of two types of exercise: the first group performed the VO2max test until exhaustion, and the second performed three times the repeated 30 s Wingate Anaerobic Test (WAnT). Blood was collected before, 15 min and one hour after the exercise. The concentration of 25(OH)D3, parathyroid hormone (PTH), interleukin-6 (IL-6), lactate, non-esterified fatty acids (NEFA) and glycerol were determined. 25(OH)D3 concentration significantly increased after the exercise in all boys. The most prominent changes in 25(OH)D3, observed after WAnT, were associated with the rise of PTH. The dimensions of response to the exercises observed through the changes in the concentration of 25(OH)D3, PTH, NEFA and glycerol were associated with the significant increases of IL-6 level. A single bout of exercise may increase the serum's 25(OH)D3 concentration in young trained boys. The intensive interval exercise brings a more potent stimulus to vitamin D fluctuations in young organisms. Our results support the hypothesis that muscles may both store and release 25(OH)D3.


Assuntos
Calcifediol/sangue , Exercício Físico/fisiologia , Músculo Esquelético/fisiologia , Hormônio Paratireóideo/sangue , Aptidão Física/fisiologia , Adolescente , Atletas , Ácidos Graxos não Esterificados/sangue , Glicerol/sangue , Humanos , Interleucina-6/sangue , Ácido Láctico/sangue , Masculino , Projetos Piloto , Testes de Função Respiratória
6.
Sci Rep ; 12(1): 271, 2022 01 07.
Artigo em Inglês | MEDLINE | ID: mdl-34997178

RESUMO

The current study was performed to evaluate the effects of alpha-lipoic acid (ALA) supplementation on lactate, nitric oxide (NO), vascular cell adhesion molecule-1 (VCAM-1) levels, and clinical symptoms in women with episodic migraines. Considering the inclusion and exclusion criteria, ninety-two women with episodic migraines participated in this randomized, double-blind, placebo-controlled, parallel-design trial. The participants were randomly assigned to receive either 300 mg/day ALA or placebo, twice per day for 12 weeks. The primary outcomes included headache severity, headache frequency per month, and duration of attacks and the secondary outcomes included lactate (a marker of mitochondrial function), NO, and VCAM-1 serum levels were measured at baseline and the end of the intervention. At the end of the study, there was a significant decrease in lactate serum levels (- 6.45 ± 0.82 mg/dl vs - 2.27 ± 1.17 mg/dl; P = 0.039) and VCAM-1 (- 2.02 ± 0.30 ng/ml vs - 1.21 ± 0.36 ng/ml; P = 0.025) in the ALA as compared to the placebo group. In addition, the severity (P < 0.001), frequency (P = 0.001), headache impact test (HIT-6) (P < 0.001), headache dairy results (HDR) (P = 0.003), and migraine headache index score (MHIS) (P < 0.001) had significantly decreased in the intervention as compared to the control group. No significant changes were observed for NO levels and duration of migraine pains. ALA supplementation can be considered a potential adjunct treatment in patients with migraine due to its improving mitochondrial and endothelial functions and clinical symptoms.


Assuntos
Suplementos Nutricionais , Transtornos de Enxaqueca/tratamento farmacológico , Ácido Tióctico/uso terapêutico , Adulto , Suplementos Nutricionais/efeitos adversos , Método Duplo-Cego , Feminino , Humanos , Irã (Geográfico) , Ácido Láctico/sangue , Transtornos de Enxaqueca/sangue , Transtornos de Enxaqueca/diagnóstico , Transtornos de Enxaqueca/fisiopatologia , Óxido Nítrico/sangue , Medição da Dor , Índice de Gravidade de Doença , Ácido Tióctico/efeitos adversos , Fatores de Tempo , Resultado do Tratamento , Molécula 1 de Adesão de Célula Vascular/sangue
7.
Comput Math Methods Med ; 2021: 9934107, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34925548

RESUMO

OBJECTIVES: To determine whether feeding CircuCare to rats improves blood circulation, metabolism, immune regulation, endocrine activity, and oxidative stress. METHODS: 28 eight-week-old male Sprague-Dawley rats were evenly randomized into control and experimental groups. The control group was fed with ordinary drinking water, while the experimental group was fed with CircuCare at a daily dose of 93.75 mg per 300 g of body weight over eight weeks. Both groups were subjected to a swimming test, and blood samples were taken to observe any variations in various biochemical parameters before and after the test. Key Findings. The experimental group's mean swimming exhaustion duration was 53.2% longer and had a significantly higher lactic acid removal ratio. Their mean prostaglandin E2 level and mean glucose, cortisol, and glutathione level (30 minutes after swimming test) were also significantly higher. No undesirable impacts from CircuCare relating to general blood biochemistry values and bone mineral density were reported. CONCLUSIONS: The present results show that CircuCare can be safely used to increase stamina and exercise capability, expedite the metabolism of lactic acid, accelerate muscle repair, and promote the antioxidant activity of cells in rats.


Assuntos
Circulação Sanguínea/efeitos dos fármacos , Medicamentos de Ervas Chinesas/farmacologia , Metabolismo/efeitos dos fármacos , Animais , Glicemia/efeitos dos fármacos , Glicemia/metabolismo , Densidade Óssea/efeitos dos fármacos , Carica/química , Biologia Computacional , Medicamentos de Ervas Chinesas/química , Glândulas Endócrinas/efeitos dos fármacos , Glândulas Endócrinas/fisiologia , Imunidade/efeitos dos fármacos , Ácido Láctico/sangue , Masculino , Modelos Animais , Estresse Oxidativo/efeitos dos fármacos , Panax/química , Esforço Físico/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley
8.
Nutrients ; 13(11)2021 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-34836350

RESUMO

The aim of this study was to investigate the impact of glucose (Glu), fructose (Fru), glucose and fructose (GluFru) and sucralose on blood glucose response in healthy individuals. Fifteen healthy individuals (five females, age of 25.4 ± 2.5 years, BMI of 23.7 ± 1.7 kg/m2 with a body mass (BM) of 76.3 ± 12.3 kg) participated in this double-blind randomized crossover placebo-controlled trial. Participants received a mixture of 300 mL of water with 1 g/kg BM of Glu, 1 g/kg BM of Fru, 0.5 g/kg BM of GluFru (each), and 0.2 g sucralose as a placebo. Peak BG values Glu were reached after 40 ± 13 min (peak BG: 141 ± 20 mg/dL), for Fru after 36 ± 22 min (peak BG: 98 ± 7 mg/dL), for GluFru after 29 ± 8 min (BG 128 ± 18 mg/dL), and sucralose after 34 ± 27 min (peak BG: 83 ± 5 mg/dL). Significant differences regarding the time until peak BG were found only between Glu and GluFru supplementation (p = 0.02). Peak blood glucose levels were significantly lower following the ingestion of Fru compared to the supplementation of Glu and GluFru (p < 0.0001) while Glu and GluFru supplementation showed no difference in peak values (p = 0.23). All conditions led to a significantly higher peak BG value compared to sucralose (p < 0.0001). Blood lactate increased in Glu (p = 0.002), Fru and GluFru (both p < 0.0001), whereas sucralose did not increase compared to the baseline (p = 0.051). Insulin levels were significantly higher in all conditions at peak compared to sucralose (p < 0.0001). The findings of this study prove the feasibility of combined carbohydrate supplementations for many applications in diabetic or healthy exercise cohorts.


Assuntos
Açúcares da Dieta/administração & dosagem , Suplementos Nutricionais , Frutose/administração & dosagem , Glucose/administração & dosagem , Sacarose/análogos & derivados , Adulto , Glicemia/metabolismo , Estudos Cross-Over , Método Duplo-Cego , Ingestão de Energia/fisiologia , Feminino , Voluntários Saudáveis , Humanos , Ácido Láctico/sangue , Masculino , Sacarose/administração & dosagem , Edulcorantes/administração & dosagem , Adulto Jovem
9.
PLoS One ; 16(11): e0259027, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34767563

RESUMO

We used measurements of metabolic perturbation obtained after sparring to estimate energetics contribution during no-gi Brazilian jiu-jitsu. Ten advanced grapplers performed two six-minute sparring bouts separated by 24 hours. Kinetics of recovery rate of oxygen uptake was modelled and post-combat-sparring blood-lactate concentration measured to estimate oxygen equivalents for phospholytic and glycolytic components of anaerobic energetics, respectively. Linear regression was used to estimate end-combat-sparring rate of oxygen uptake. Regional and whole-body composition were assessed using dual X-ray absorptiometry with associations between these measurements and energy turnover explored using Pearson's correlation coefficient (significance, P < 0.05). Estimated oxygen equivalents for phospholytic and glycolytic contributions to anaerobic metabolism were 16.9 ± 8.4 (~28%) and 44.6 ± 13.5 (~72%) mL∙kg-1, respectively. Estimated end-exercise rate of oxygen uptake was 44.2 ± 7.0 mL∙kg-1∙min-1. Trunk lean mass was positively correlated with both total anaerobic and glycolytic-specific energetics (total, R = 0.645, p = 0.044; glycolytic, R = 0.692, p = 0.027) and negatively correlated with end-exercise rate of oxygen uptake (R = -0.650, p = 0.042). There were no correlations for any measurement of body composition and phospholytic-specific energetics. Six minutes of no-gi Brazilian jiu-jitsu sparring involves high relative contribution from the glycolytic component to total anaerobic energy provision and the link between this energetics profile and trunk lean mass is consistent with the predominance of ground-based combat that is unique for this combat sport. Training programs for Brazilian jiu-jitsu practitioners should be designed with consideration given to these specific energetics characteristics.


Assuntos
Anaerobiose/fisiologia , Atletas , Composição Corporal/fisiologia , Exercício Físico/fisiologia , Glicólise/fisiologia , Artes Marciais/fisiologia , Transdução de Sinais/fisiologia , Absorciometria de Fóton/métodos , Adulto , Brasil , Humanos , Ácido Láctico/sangue , Masculino , Oxigênio/metabolismo , Adulto Jovem
10.
J Sports Sci Med ; 20(2): 310-316, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-34211324

RESUMO

The present study aimed to propose and assess the physiological responses of a novel graded karate test. Ten male national-level karate athletes (age 26 ± 5 yrs; body mass 69.5 ± 11.6 kg; height 1.70 ± 0.09 m) performed two exercise tests (separated by 2-7 days): 1) a running-based cardiopulmonary exercise test; 2) a graded karate test. The cardiopulmonary exercise test was comprised of an individualized ramp protocol for treadmill running, and the graded karate test was comprised of a sequence of 'kisami-gyaku-zuki" punching at a fixed frequency of a stationary target that becomes progressively distant. Cardiorespiratory responses, blood lactate concentration, and perceived exertion were measured. A verification phase was also performed in both tests to confirm the maximal physiological outcomes. The graded karate test evoked similar maximal responses to the running protocol: V̇O2 (57.4 ± 5.1 vs 58.3 ± 3.5 mL·kg-1·min-1; p = 0.53), heart rate (192 ± 6 vs 193 ± 10]beats.min-1; p = 0.62) and blood lactate (14.6 ± 3.4 vs 13.1 ± 3.0 mmol·L-1; p = 0.14) with a shorter duration (351 ± 71 vs 640 ± 9 s; p < 0.001). Additionally, the graded karate test evoked higher V̇O2 (72.6 ± 6.5 vs 64.4 ± 4.3 %V̇O2MAX; p = 0.005) and heart rate (89.4 ± 4.6 vs 77.3 ± 7.2 %HRMAX p < 0.001) at the ventilatory threshold and a higher heart rate (97.0 ± 2.4 vs 92.9 ± 2.2 %HRMAX; p = 0.02) at the respiratory compensation point. Incremental and verification phases evoked similar responses in V̇O2 and minute-ventilation during both tests. This novel displacement-based sport-specific test evoked similar maximal and higher submaximal responses, indicating a superior pathway to assess karate athletes.


Assuntos
Aptidão Cardiorrespiratória/fisiologia , Teste de Esforço/métodos , Artes Marciais/fisiologia , Adulto , Limiar Anaeróbio , Frequência Cardíaca , Humanos , Ácido Láctico/sangue , Masculino , Percepção/fisiologia , Esforço Físico/fisiologia
11.
J Int Soc Sports Nutr ; 18(1): 55, 2021 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-34243756

RESUMO

BACKGROUND: Nitrate supplementation is thought to improve performance in endurance sports. OBJECTIVE: To meta-analyze studies evaluating the effect of nitrate supplementation on endurance sports performance among adults. DATA SOURCES: We searched the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, EMBASE, Web of Science and CINAHL without language restrictions. METHODS: We included studies that: 1) compared nitrate supplementation with placebo; 2) enrolled adults engaging in an endurance-based activity; and 3) reported a performance measure or surrogate physiologic outcome. We evaluated risk of bias using the Cochrane Collaboration tool and pooled data with a random-effects model. We used the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach to evaluate confidence in estimates. RESULTS: We included 73 studies (n = 1061). Nitrate supplementation improved power output (MD 4.6 watts, P < 0.0001), time to exhaustion (MD 25.3 s, P < 0.00001), and distance travelled (MD 163.7 m, P = 0.03). We found no significant difference on perceived exertion, time trial performance and work done. Nitrate supplementation decreased VO2 (MD - 0.04 L/min, P < 0.00001) but had no significant effect on VO2max or blood lactate levels. CONCLUSION: The available evidence suggests that dietary nitrate supplementation benefits performance-related outcomes for endurance sports.


Assuntos
Desempenho Atlético/fisiologia , Suplementos Nutricionais , Nitratos/administração & dosagem , Resistência Física/fisiologia , Adulto , Atletas , Viés , Aptidão Cardiorrespiratória/fisiologia , Tolerância ao Exercício/fisiologia , Humanos , Ácido Láctico/sangue , Consumo de Oxigênio/fisiologia , Viés de Publicação , Comportamento Sedentário , Fatores de Tempo
12.
J Int Soc Sports Nutr ; 18(1): 49, 2021 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-34147116

RESUMO

PURPOSE: Previous investigations have found positive effects of acute ingestion of capsules containing 4-to-9 mg of caffeine per kg of body mass on several aspects of judo performance. However, no previous investigation has tested the effectiveness of caffeinated chewing gum as the form of caffeine administration for judoists. The main goal of this study was to assess the effect of acute ingestion of a caffeinated chewing gum on the results of the special judo fitness test (SJFT). METHODS: Nine male elite judo athletes of the Polish national team (23.7 ± 4.4 years, body mass: 73.5 ± 7.4 kg) participated in a randomized, crossover, placebo-controlled and double-blind experiment. Participants were moderate caffeine consumers (3.1 mg/kg/day). Each athlete performed three identical experimental sessions after: (a) ingestion of two non-caffeinated chewing gums (P + P); (b) a caffeinated chewing gum and a placebo chewing gum (C + P; ~2.7 mg/kg); (c) two caffeinated chewing gums (C + C; ~5.4 mg/kg). Each gum was ingested 15 min before performing two Special Judo Fitness Test (SJFT) which were separated by 4 min of combat activity. RESULTS: The total number of throws was not different between P + P, C + P, and C + C (59.66 ± 4.15, 62.22 ± 4.32, 60.22 ± 4.08 throws, respectively; p = 0.41). A two-way repeated measures ANOVA indicated no significant substance × time interaction effect as well as no main effect of caffeine for SJFT performance, SJFT index, blood lactate concentration, heart rate or rating of perceived exertion. CONCLUSIONS: The results of the current study indicate that the use of caffeinated chewing gum in a dose up to 5.4 mg/kg of caffeine did not increase performance during repeated SJFTs.


Assuntos
Atletas , Desempenho Atlético , Cafeína/farmacologia , Estimulantes do Sistema Nervoso Central/farmacologia , Goma de Mascar , Artes Marciais/fisiologia , Desempenho Atlético/fisiologia , Desempenho Atlético/estatística & dados numéricos , Cafeína/administração & dosagem , Estimulantes do Sistema Nervoso Central/administração & dosagem , Estudos Cross-Over , Método Duplo-Cego , Frequência Cardíaca , Humanos , Ácido Láctico/sangue , Masculino , Artes Marciais/estatística & dados numéricos , Aptidão Física , Placebos/administração & dosagem , Adulto Jovem
13.
Nutrients ; 13(5)2021 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-34063516

RESUMO

The Taiwan Tilapia is an important aquaculture product in Taiwan. The aquatic by-products generated during Tilapia processing, such as fish bones and skin, are rich in minerals and protein. We aimed to explore the effect of a dietary supplement, comprising a mixture of fermented Tilapia by-products and Monostroma nitidum oligosaccharides as the raw materials, combined with physical training on exercise performance and fatigue. We used a mouse model that displays a phenotype of accelerated aging. Male senescence-accelerated mouse prone-8 (SAMP8) mice were divided into two control groups-with or without physical training-and supplemented with different doses (0.5 times: 412 mg/kg body weight (BW)/day; 1 time: 824 mg/kg BW/day; 2 times: 1648 mg/kg BW/day) of fermented Tilapia by-products and Monostroma nitidum oligosaccharide-containing mixture and combined with exercise training groups. Exercise performance was determined by testing forelimb grip strength and with a weight-bearing exhaustive swimming test. Animals were sacrificed to collect physical fatigue-related biomarkers. Mice dosed at 824 or 1648 mg/kg BW/day showed improvement in their exercise performance (p < 0.05). In terms of biochemical fatigue indicators, supplementation of 824 or 1648 mg/kg BW/day doses of test substances could effectively reduce blood urea nitrogen concentration and lactate concentration and increase the lactate ratio (p < 0.05) and liver glycogen content post-exercise (p < 0.05). Based on the above results, the combination of physical training and consumption of a dietary supplementation mixture of fermented Tilapia by-products and Monostroma nitidum oligosaccharides could improve the exercise performance of mice and help achieve an anti-fatigue effect.


Assuntos
Suplementos Nutricionais , Fadiga/dietoterapia , Alimentos Fermentados , Oligossacarídeos/farmacologia , Tilápia , Animais , Biomarcadores/sangue , Nitrogênio da Ureia Sanguínea , Osso e Ossos , Modelos Animais de Doenças , Fadiga/metabolismo , Fermentação , Ácido Láctico/sangue , Masculino , Camundongos , Condicionamento Físico Animal , Natação , Taiwan
14.
J Int Soc Sports Nutr ; 18(1): 39, 2021 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-34039357

RESUMO

BACKGROUND: Taurine has become a popular supplement among athletes attempting to improve performance. While the effectiveness of taurine as an ergogenic aid remains controversial, this paper summarizes the current evidence regarding the efficacy of taurine in aerobic and anaerobic performance, metabolic stress, muscle soreness, and recovery. METHODS: Google Scholar, Web of Science, and MedLine (PubMed) searches were conducted through September 2020. Peer-reviewed studies that investigated taurine as a single ingredient at dosages of < 1 g - 6 g, ranging from 10 to 15 min-to-2 h prior to exercise bout or chronic dose (7 days- 8 weeks) of consumption were included. Articles were excluded if taurine was not the primary or only ingredient in a supplement or food source, not published in peer-reviewed journals, if participants were older than 50 years, articles published before 1999, animal studies, or included participants with health issues. A total of 19 studies met the inclusion criteria for the review. RESULTS: Key results include improvements in the following: VO2max, time to exhaustion (TTE; n = 5 articles), 3 or 4 km time-trial (n = 2 articles), anaerobic performance (n = 7 articles), muscle damage (n = 3 articles), peak power (n = 2 articles), recovery (n = 1 article). Taurine also caused a change in metabolites: decrease in lactate, creatine kinase, phosphorus, inflammatory markers, and improved glycolytic/fat oxidation markers (n = 5 articles). Taurine dosing appears to be effective at ~ 1-3 g/day acutely across a span of 6-15 days (1-3 h before an activity) which may improve aerobic performance (TTE), anaerobic performance (strength, power), recovery (DOMS), and a decrease in metabolic markers (creatine kinase, lactate, inorganic phosphate). CONCLUSIONS: Limited and varied findings prohibit definitive conclusions regarding the efficacy of taurine on aerobic and anaerobic performance and metabolic outcomes. There are mixed findings for the effect of taurine consumption on improving recovery from training bouts and/or mitigating muscle damage. The timing of taurine ingestion as well as the type of exercise protocol performed may contribute to the effectiveness of taurine as an ergogenic aid. More investigations are needed to better understand the potential effects of taurine supplementation on aerobic and anaerobic performance, muscle damage, metabolic stress, and recovery.


Assuntos
Desempenho Atlético/fisiologia , Suplementos Nutricionais , Substâncias para Melhoria do Desempenho/administração & dosagem , Taurina/administração & dosagem , Glicemia/metabolismo , Regulação da Temperatura Corporal , Cálcio/metabolismo , Metabolismo Energético , Humanos , Inflamação/prevenção & controle , Ácido Láctico/sangue , Metabolismo dos Lipídeos , Força Muscular , Mialgia/prevenção & controle , Estresse Oxidativo , Consumo de Oxigênio , Substâncias para Melhoria do Desempenho/farmacocinética , Taurina/farmacocinética
15.
Sci Rep ; 11(1): 11148, 2021 05 27.
Artigo em Inglês | MEDLINE | ID: mdl-34045508

RESUMO

This study investigated the effects of inspiratory muscle pre-activation (IMPA) on the interactions among the technical-tactical, physical, physiological, and psychophysiological parameters in a simulated judo match, based on the centrality metrics by complex network model. Ten male athletes performed 4 experimental sessions. Firstly, anthropometric measurements, maximal inspiratory pressure (MIP) and global strenght of the inspiratory muscles were determined. In the following days, all athletes performed four-minute video-recorded judo matches, under three conditions: without IMPA (CON), after IMPA at 15% (IMPA15), and at 40% (IMPA40) of MIP using an exerciser device. Blood lactate, heart rate and rating of perceived exertion were monitored, and the technical-tactical parameters during the match were related to offensive actions and the time-motion. Based on the complex network, graphs were constructed for each scenario (CON, IMPA15, and IMPA40) to investigate the Degree and Pagerank centrality metrics. IMPA40 increased the connectivity of the physical and technical-tactical parameters in complex network and highlighted the combat frequency and average combat time in top-five ranked nodes. IMPA15 also favoured the interactions among the psychophysiological, physical, and physiological parameters. Our results suggest the positive effects of the IMPA, indicating this strategy to prepare the organism (IMPA15) and to improve performance (IMPA40) in judo match.


Assuntos
Desempenho Atlético/fisiologia , Músculos Respiratórios/fisiologia , Atletas , Força da Mão/fisiologia , Frequência Cardíaca/fisiologia , Humanos , Ácido Láctico/sangue , Masculino , Artes Marciais , Modelos Teóricos , Adulto Jovem
16.
Ann Intern Med ; 174(7): 927-935, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33872042

RESUMO

BACKGROUND: Medicare requires that hospitals report on their adherence to the Severe Sepsis and Septic Shock Early Management Bundle (SEP-1). OBJECTIVE: To evaluate the effect of SEP-1 on treatment patterns and patient outcomes. DESIGN: Longitudinal study of hospitals using repeated cross-sectional cohorts of patients. SETTING: 11 hospitals within an integrated health system. PATIENTS: 54 225 encounters between January 2013 and December 2017 for adults with sepsis who were hospitalized through the emergency department. INTERVENTION: Onset of the SEP-1 reporting requirement in October 2015. MEASUREMENTS: Changes in SEP-1-targeted processes, including antibiotic administration, lactate measurement, and fluid administration at 3 hours from sepsis onset; repeated lactate and vasopressor administration for hypotension within 6 hours of sepsis onset; and sepsis outcomes, including risk-adjusted intensive care unit (ICU) admission, in-hospital mortality, and home discharge among survivors. RESULTS: Two years after its implementation, SEP-1 was associated with variable changes in process measures, with the greatest effect being an increase in lactate measurement within 3 hours of sepsis onset (absolute increase, 23.7 percentage points [95% CI, 20.7 to 26.7 percentage points]; P < 0.001). There were small increases in antibiotic administration (absolute increase, 4.7 percentage points [CI, 1.9 to 7.6 percentage points]; P = 0.001) and fluid administration of 30 mL/kg of body weight within 3 hours of sepsis onset (absolute increase, 3.4 percentage points [CI, 1.5 to 5.2 percentage points]; P < 0.001). There was no change in vasopressor administration. There was a small increase in ICU admissions (absolute increase, 2.0 percentage points [CI, 0 to 4.0 percentage points]; P = 0.055) and no changes in mortality (absolute change, 0.1 percentage points [CI, -0.9 to 1.1 percentage points]; P = 0.87) or discharge to home. LIMITATION: Data are from a single health system. CONCLUSION: Implementation of the SEP-1 mandatory reporting program was associated with variable changes in process measures, without improvements in clinical outcomes. Revising the measure may optimize its future effect. PRIMARY FUNDING SOURCE: Agency for Healthcare Research and Quality.


Assuntos
Medicare/organização & administração , Avaliação de Resultados em Cuidados de Saúde , Pacotes de Assistência ao Paciente/normas , Sepse/terapia , Idoso , Idoso de 80 Anos ou mais , Antibacterianos/uso terapêutico , Estudos Transversais , Feminino , Hidratação , Fidelidade a Diretrizes , Humanos , Ácido Láctico/sangue , Estudos Longitudinais , Masculino , Notificação de Abuso , Pessoa de Meia-Idade , Guias de Prática Clínica como Assunto , Melhoria de Qualidade , Sepse/sangue , Estados Unidos , Vasoconstritores/uso terapêutico
17.
Scand J Clin Lab Invest ; 81(4): 312-317, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33879006

RESUMO

Intestinal infarction is the fast-evolving endpoint of impaired blood perfusion to an intestinal segment which may have fatal outcome. Early diagnosis and treatment within 6 h reduce mortality. Currently, d-lactate is a promising biomarker, however, not available in the acute clinical setting. The aim of this study is implementation of d-lactate analysis in a routine clinical setting. We used a spectrophotometric method, based on enzymatic oxidation of d-lactate by d-lactate dehydrogenase (D-LDH) coupled to the reduction of nicotinamide-adenine dinucleotide (NAD+). The amount of NADH formed in this reaction is equivalent to d-lactate. The primary concern in this method is interfering NADH formed by oxidation of l-lactate by l-lactate dehydrogenase (L-LDH). A commercially available kit for d-lactate measurement was implemented on our existing automated routine laboratory equipment including pH-inactivation of L-LDH. Our setup fulfilled clinical quality goals. We were able to measure d-lactate with an acceptable performance of the analysis and a short turn-around time. The method can be used to distinguish between the expected cut-off for intestinal ischemia around 0.3 mM and the upper reference limit of 0.05 mM. With a turnaround time of just 9 min, the analysis has potential as a readily available detection of circulating d-lactate for early diagnosis of intestinal ischemia.


Assuntos
Análise Química do Sangue/métodos , Ácido Láctico/sangue , Automação Laboratorial , Emulsões/administração & dosagem , Humanos , Concentração de Íons de Hidrogênio , L-Lactato Desidrogenase/sangue , Limite de Detecção , Isquemia Mesentérica/sangue , NAD/metabolismo , Fosfolipídeos/administração & dosagem , Kit de Reagentes para Diagnóstico , Reprodutibilidade dos Testes , Óleo de Soja/administração & dosagem , Espectrofotometria
18.
Nutrients ; 13(4)2021 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-33801665

RESUMO

The assessment of ventilatory efficiency is critical to understanding the matching of ventilation (VE) and perfusion in the lungs during exercise. This study aimed to establish a causal physiological relationship between ventilatory efficiency and resistance exercise performance after beetroot juice (BJ) intake. Eleven well-trained males performed a resistance exercise test after drinking 140 mL of BJ (~12.8 mmol NO3-) or a placebo (PL). Ventilatory efficiency was assessed by the VE•VCO2-1 slope, the oxygen uptake efficiency slope and the partial pressure of end-tidal carbon dioxide (PetCO2). The two experimental conditions were controlled using a randomized, double-blind crossover design. The resistance exercise test involved repeating the same routine twice, which consisted of wall ball shots plus a full squat (FS) with a 3 min rest or without a rest between the two exercises. A higher weight lifted was detected in the FS exercise after BJ intake compared with the PL during the first routine (p = 0.004). BJ improved the VE•VCO2-1 slope and the PetCO2 during the FS exercise in the first routine and at rest (p < 0.05). BJ intake improved the VE•VCO2-1 slope and the PetCO2 coinciding with the resistance exercise performance. The ergogenic effect of BJ could be induced under aerobic conditions at rest.


Assuntos
Atletas , Beta vulgaris/química , Sucos de Frutas e Vegetais , Treinamento Resistido , Fenômenos Fisiológicos Respiratórios/efeitos dos fármacos , Adulto , Estudos Cross-Over , Método Duplo-Cego , Humanos , Ácido Láctico/sangue , Masculino , Consumo de Oxigênio/fisiologia , Troca Gasosa Pulmonar/fisiologia
19.
J Int Soc Sports Nutr ; 18(1): 26, 2021 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-33781280

RESUMO

BACKGROUND: Blueberries are concentrated with anthocyanins possessing antioxidant properties. As these properties counter fatigue, blueberry supplementation may improve performance and recovery, particularly in hypoxia, where oxidative stress is elevated. METHODS: This study examined the effects of blueberry supplementation on running performance, physiological responses, and recovery in normobaric hypoxia. Eleven experienced runners completed a 30-minute time-trial (TT) in normobaric hypoxia (%O2 = 15.5 %) on separate days after supplementation with four days of blueberries (BLU) or four days of placebo (PLA). Heart rate (HR), oxygen saturation (SaO2) and ratings of perceived exertion (RPE) were monitored during the TT. Blood lactate and fraction of exhaled nitric oxide (FENO) were assessed pre-TT, post-TT, and during recovery. RESULTS: No significant differences were observed in the distance run during the TT, HR, SaO2, and RPE. The post-TT increase in blood lactate was significantly lower in BLU than PLA (p = 0.036). Pre-TT and post-TT FENO did not differ between conditions. Blood lactate recovery following the TT was similar between conditions. CONCLUSIONS: Four days of blueberry supplementation did not alter running performance or cardiovascular and perceptual responses in normobaric hypoxia. Supplementation lowered the blood lactate response to running, however, the significance of this finding is uncertain given the absence of an ergogenic effect.


Assuntos
Antocianinas/administração & dosagem , Desempenho Atlético/fisiologia , Mirtilos Azuis (Planta) , Suplementos Nutricionais , Ácido Láctico/sangue , Substâncias para Melhoria do Desempenho/administração & dosagem , Corrida/fisiologia , Adulto , Biomarcadores/metabolismo , Estudos Cross-Over , Método Duplo-Cego , Teste de Esforço , Feminino , Frequência Cardíaca , Humanos , Hipóxia/fisiopatologia , Masculino , Estresse Oxidativo , Oxigênio/sangue , Percepção/fisiologia , Resistência Física/fisiologia , Saliva/metabolismo , Adulto Jovem
20.
Medicine (Baltimore) ; 100(5): e23971, 2021 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-33592851

RESUMO

BACKGROUND: The purpose of this study is to explore the association between extravascular lung water (EVLW) and prognosis of sepsis (PS). METHODS: We will carry out comprehensive literature search in electronic databases (PUBMED/MEDLINE, EMBASE, CENTRAL, WorldSciNet, PsycINFO, Allied and Complementary Medicine Database, CBM, and CNKI) and additional sources. All electronic databases will be searched from their initial to the present without language restrictions. Case-controlled studies reporting the association between EVLW and PS will be evaluated for inclusion. Outcomes of interest will include mortality rate, extravascular lung water index, pulmonary vascular permeability index, blood lactate clearance, oxygenation index, blood gas analysis, PaO2/FiO2, cardiac output index, global end diastolic volume index, intrathoracic blood volume index, systemic resistance index, acute physiology and chronic health scoring system II, and infection-related organ failure scoring system. Study quality will be evaluated using Newcastle-Ottawa Tool, and statistical analysis will be performed utilizing RevMan 5.4 software. RESULTS: This study will summarize the most recent evidence to investigate the association between EVLW and PS. CONCLUSIONS: The results of this study will provide an exhaustive view of the association between EVLW and PS. STUDY REGISTRATION OSF: osf.io/vhnxw.


Assuntos
Água Extravascular Pulmonar/metabolismo , Sepse/mortalidade , Sepse/fisiopatologia , APACHE , Gasometria , Pressão Sanguínea , Permeabilidade Capilar , Débito Cardíaco , Estudos de Casos e Controles , Humanos , Ácido Láctico/sangue , Escores de Disfunção Orgânica , Consumo de Oxigênio , Prognóstico , Circulação Pulmonar , Projetos de Pesquisa , Medição de Risco , Fatores de Risco , Revisões Sistemáticas como Assunto
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