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1.
Nutrients ; 13(8)2021 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-34444681

RESUMO

Creatine (Cr) and phosphocreatine (PCr) are physiologically essential molecules for life, given they serve as rapid and localized support of energy- and mechanical-dependent processes. This evolutionary advantage is based on the action of creatine kinase (CK) isozymes that connect places of ATP synthesis with sites of ATP consumption (the CK/PCr system). Supplementation with creatine monohydrate (CrM) can enhance this system, resulting in well-known ergogenic effects and potential health or therapeutic benefits. In spite of our vast knowledge about these molecules, no integrative analysis of molecular mechanisms under a systems biology approach has been performed to date; thus, we aimed to perform for the first time a convergent functional genomics analysis to identify biological regulators mediating the effects of Cr supplementation in health and disease. A total of 35 differentially expressed genes were analyzed. We identified top-ranked pathways and biological processes mediating the effects of Cr supplementation. The impact of CrM on miRNAs merits more research. We also cautiously suggest two dose-response functional pathways (kinase- and ubiquitin-driven) for the regulation of the Cr uptake. Our functional enrichment analysis, the knowledge-based pathway reconstruction, and the identification of hub nodes provide meaningful information for future studies. This work contributes to a better understanding of the well-reported benefits of Cr in sports and its potential in health and disease conditions, although further clinical research is needed to validate the proposed mechanisms.


Assuntos
Creatina/administração & dosagem , Perfilação da Expressão Gênica , Genômica/métodos , Desempenho Físico Funcional , Animais , Creatina/metabolismo , Creatina Quinase/metabolismo , Suplementos Nutricionais , Metabolismo Energético , Estudo de Associação Genômica Ampla , Humanos , Camundongos , Proteínas Quinases Ativadas por Mitógeno , Proteínas de Transporte de Neurotransmissores , Fosfocreatina/metabolismo , Transdução de Sinais
2.
Nutrients ; 13(7)2021 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-34209814

RESUMO

Sport nutrition knowledge has been shown to influence dietary habits of athletes. The purpose of the current study was to examine relationships between sport nutrition knowledge and body composition and examine potential predictors of body weight goals in collegiate athletes. Participants included National Collegiate Athletic Association Division III women (n = 42, height: 169.9 ± 6.9 cm; body mass: 67.1 ± 8.6 kg; fat-free mass: 51.3 ± 6.6 kg; body fat per cent: 24.2 ± 5.3%) and men (n = 25, height: 180.8 ± 7.2 cm; body mass: 89.2 ± 20.5 kg; fat-free mass: 75.9 ± 12.2 kg; body fat per cent: 13.5 ± 8.9%) athletes. Body composition was assessed via air displacement plethysmography. Athletes completed a validated questionnaire designed to assess sport nutrition knowledge and were asked questions about their perceived dietary energy and macronutrient requirements, as well as their body weight goal (i.e., lose, maintain, gain weight). Athletes answered 47.98 ± 11.29% of questions correctly on the nutrition questionnaire with no differences observed between sexes (men: 49.52 ± 11.76% vs. women: 47.03 ± 11.04%; p = 0.40). An inverse relationship between sport nutrition knowledge scores and body fat percentage (BF%) (r = -0.330; p = 0.008), and fat mass (r = -0.268; p = 0.032) was observed for all athletes. Fat mass (ß = 0.224), BF% (ß = 0.217), and body mass index (BMI) (ß = 0.421) were all significant (p < 0.05) predictors of body weight goal in women. All athletes significantly (p < 0.001) underestimated daily energy (-1360 ± 610.2 kcal/day), carbohydrate (-301.6 ± 149.2 grams/day [g/day]), and fat (-41.4 ± 34.5 g/day) requirements. Division III collegiate athletes have a low level of sport nutrition knowledge, which was associated with a higher BF%. Women athletes with a higher body weight, BF% and BMI were more likely to select weight loss as a body weight goal. Athletes also significantly underestimated their energy and carbohydrate requirements based upon the demands of their sport, independent of sex.


Assuntos
Atletas/psicologia , Composição Corporal , Comportamento Alimentar/psicologia , Conhecimentos, Atitudes e Prática em Saúde , Fenômenos Fisiológicos da Nutrição Esportiva , Índice de Massa Corporal , Peso Corporal , Feminino , Humanos , Masculino , Necessidades Nutricionais , Percepção , Pletismografia , Universidades , Adulto Jovem
3.
Nutrients ; 13(6)2021 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-34200501

RESUMO

Adequate dietary protein is important for many aspects of health with current evidence suggesting that exercising individuals need greater amounts of protein. When assessing protein quality, animal sources of protein routinely rank amongst the highest in quality, largely due to the higher levels of essential amino acids they possess in addition to exhibiting more favorable levels of digestibility and absorption patterns of the amino acids. In recent years, the inclusion of plant protein sources in the diet has grown and evidence continues to accumulate on the comparison of various plant protein sources and animal protein sources in their ability to stimulate muscle protein synthesis (MPS), heighten exercise training adaptations, and facilitate recovery from exercise. Without question, the most robust changes in MPS come from efficacious doses of a whey protein isolate, but several studies have highlighted the successful ability of different plant sources to significantly elevate resting rates of MPS. In terms of facilitating prolonged adaptations to exercise training, multiple studies have indicated that a dose of plant protein that offers enough essential amino acids, especially leucine, consumed over 8-12 weeks can stimulate similar adaptations as seen with animal protein sources. More research is needed to see if longer supplementation periods maintain equivalence between the protein sources. Several practices exist whereby the anabolic potential of a plant protein source can be improved and generally, more research is needed to best understand which practice (if any) offers notable advantages. In conclusion, as one considers the favorable health implications of increasing plant intake as well as environmental sustainability, the interest in consuming more plant proteins will continue to be present. The evidence base for plant proteins in exercising individuals has seen impressive growth with many of these findings now indicating that consumption of a plant protein source in an efficacious dose (typically larger than an animal protein) can instigate similar and favorable changes in amino acid update, MPS rates, and exercise training adaptations such as strength and body composition as well as recovery.


Assuntos
Adaptação Fisiológica , Exercício Físico/fisiologia , Proteínas de Plantas/farmacologia , Animais , Humanos , Proteínas Musculares/metabolismo , Músculo Esquelético/fisiologia , Plantas/química
4.
Nutrients ; 13(7)2021 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-34202877

RESUMO

Glucosamine (GLU) is a natural compound found in cartilage, and supplementation with glucosamine has been shown to improve joint heath and has been linked to reduced mortality rates. GLU is poorly absorbed and may exhibit functional properties in the gut. The purpose of this study was to examine the impact of glucosamine on gastrointestinal function as well as changes in fecal microbiota and metabolome. Healthy males (n = 6) and females (n = 5) (33.4 ± 7.7 years, 174.1 ± 12.0 cm, 76.5 ± 12.9 kg, 25.2 ± 3.1 kg/m2, n = 11) completed two supplementation protocols that each spanned three weeks separated by a washout period that lasted two weeks. In a randomized, double-blind, placebo-controlled, crossover fashion, participants ingested a daily dose of GLU hydrochloride (3000 mg GlucosaGreen®, TSI Group Ltd., Missoula, MT, USA) or maltodextrin placebo. Study participants completed bowel habit and gastrointestinal symptoms questionnaires in addition to providing a stool sample that was analyzed for fecal microbiota and metabolome at baseline and after the completion of each supplementation period. GLU significantly reduced stomach bloating and showed a trend towards reducing constipation and hard stools. Phylogenetic diversity (Faith's PD) and proportions of Pseudomonadaceae, Peptococcaceae, and Bacillaceae were significantly reduced following GLU consumption. GLU supplementation significantly reduced individual, total branched-chain, and total amino acid excretion, with no glucosamine being detected in any of the fecal samples. GLU had no effect on fecal short-chain fatty acids levels. GLU supplementation provided functional gut health benefits and induced fecal microbiota and metabolome changes.


Assuntos
Suplementos Nutricionais , Microbioma Gastrointestinal/efeitos dos fármacos , Trato Gastrointestinal/efeitos dos fármacos , Glucosamina/administração & dosagem , Adulto , Estudos Cross-Over , Defecação/efeitos dos fármacos , Método Duplo-Cego , Fezes/química , Fezes/microbiologia , Feminino , Voluntários Saudáveis , Humanos , Masculino , Filogenia , Projetos Piloto , Polissacarídeos/administração & dosagem
5.
Nutrients ; 13(6)2021 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-34199588

RESUMO

Creatine is one of the most studied and popular ergogenic aids for athletes and recreational weightlifters seeking to improve sport and exercise performance, augment exercise training adaptations, and mitigate recovery time. Studies consistently reveal that creatine supplementation exerts positive ergogenic effects on single and multiple bouts of short-duration, high-intensity exercise activities, in addition to potentiating exercise training adaptations. In this respect, supplementation consistently demonstrates the ability to enlarge the pool of intracellular creatine, leading to an amplification of the cell's ability to resynthesize adenosine triphosphate. This intracellular expansion is associated with several performance outcomes, including increases in maximal strength (low-speed strength), maximal work output, power production (high-speed strength), sprint performance, and fat-free mass. Additionally, creatine supplementation may speed up recovery time between bouts of intense exercise by mitigating muscle damage and promoting the faster recovery of lost force-production potential. Conversely, contradictory findings exist in the literature regarding the potential ergogenic benefits of creatine during intermittent and continuous endurance-type exercise, as well as in those athletic tasks where an increase in body mass may hinder enhanced performance. The purpose of this review was to summarize the existing literature surrounding the efficacy of creatine supplementation on exercise and sports performance, along with recovery factors in healthy populations.


Assuntos
Desempenho Atlético/fisiologia , Creatina/farmacologia , Suplementos Nutricionais , Exercício Físico/fisiologia , Trifosfato de Adenosina , Atletas , Bases de Dados Factuais , Humanos , Músculo Esquelético , Substâncias para Melhoria do Desempenho/farmacologia
6.
Nutrients ; 13(4)2021 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-33918657

RESUMO

Creatine (Cr) is a ubiquitous molecule that is synthesized mainly in the liver, kidneys, and pancreas. Most of the Cr pool is found in tissues with high-energy demands. Cr enters target cells through a specific symporter called Na+/Cl--dependent Cr transporter (CRT). Once within cells, creatine kinase (CK) catalyzes the reversible transphosphorylation reaction between [Mg2+:ATP4-]2- and Cr to produce phosphocreatine (PCr) and [Mg2+:ADP3-]-. We aimed to perform a comprehensive and bioinformatics-assisted review of the most recent research findings regarding Cr metabolism. Specifically, several public databases, repositories, and bioinformatics tools were utilized for this endeavor. Topics of biological complexity ranging from structural biology to cellular dynamics were addressed herein. In this sense, we sought to address certain pre-specified questions including: (i) What happens when creatine is transported into cells? (ii) How is the CK/PCr system involved in cellular bioenergetics? (iii) How is the CK/PCr system compartmentalized throughout the cell? (iv) What is the role of creatine amongst different tissues? and (v) What is the basis of creatine transport? Under the cellular allostasis paradigm, the CK/PCr system is physiologically essential for life (cell survival, growth, proliferation, differentiation, and migration/motility) by providing an evolutionary advantage for rapid, local, and temporal support of energy- and mechanical-dependent processes. Thus, we suggest the CK/PCr system acts as a dynamic biosensor based on chemo-mechanical energy transduction, which might explain why dysregulation in Cr metabolism contributes to a wide range of diseases besides the mitigating effect that Cr supplementation may have in some of these disease states.


Assuntos
Biologia Computacional , Creatina/metabolismo , Doença , Saúde , Animais , Transporte Biológico , Creatina/biossíntese , Creatina/química , Creatina Quinase/metabolismo , Humanos
7.
Sports (Basel) ; 9(4)2021 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-33918193

RESUMO

Energy needs of female team-sport athletes are poorly understood with no evidence highlighting differences present between scheduled activities. The purpose of this study was to examine the difference in energy expenditure between NCAA Division II female basketball (BBALL) and lacrosse (LAX) athletes during different scheduled team activities. Female BBALL (n = 13; 19.8 ± 1.3 yrs; 173.9 ± 13.6 cm; 74.6 ± 9.1kg; 27.1 ± 3.2%fat) and LAX (n = 20; 20.4 ± 1.8yrs; 168.4 ± 6.6cm; 68.8 ± 8.9kg; 27.9 ± 3.1%fat) athletes were outfitted with heart rate and activity monitors during four consecutive days on five different occasions (20 days total) across an entire academic year to assess differences in total daily activity energy expenditure (TDEE), activity energy expenditure (AEE), and physical activity level (PAL). Data were categorized by type of scheduled daily activities: Practice, Game, Conditioning, or Off. Independent of day type, TDEE, AEE, and PAL levels were greater (p < 0.05) in BBALL athletes. For each sport, TDEE, AEE, and PAL were significantly different (p < 0.05) between classified activity days. BBALL and LAX athletes experienced higher values on game days for TDEE, AEE, and PAL, with the lowest values experienced on off days. In conclusion, calculated levels of TDEE, AEE, and PAL in female collegiate BBALL and LAX athletes were determined to be different, irrespective of the scheduled activity.

8.
Nutrients ; 13(2)2021 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-33670822

RESUMO

Creatine is a popular ergogenic aid among athletic populations with consistent evidence indicating that creatine supplementation also continues to be commonly used among adolescent populations. In addition, the evidence base supporting the therapeutic benefits of creatine supplementation for a plethora of clinical applications in both adults and children continues to grow. Among pediatric populations, a strong rationale exists for creatine to afford therapeutic benefits pertaining to multiple neuromuscular and metabolic disorders, with preliminary evidence for other subsets of clinical populations as well. Despite the strong evidence supporting the efficacy and safety of creatine supplementation among adult populations, less is known as to whether similar physiological benefits extend to children and adolescent populations, and in particular those adolescent populations who are regularly participating in high-intensity exercise training. While limited in scope, studies involving creatine supplementation and exercise performance in adolescent athletes generally report improvements in several ergogenic outcomes with limited evidence of ergolytic properties and consistent reports indicating no adverse events associated with supplementation. The purpose of this article is to summarize the rationale, prevalence of use, performance benefits, clinical applications, and safety of creatine use in children and adolescents.


Assuntos
Desempenho Atlético/fisiologia , Creatina/administração & dosagem , Suplementos Nutricionais , Substâncias para Melhoria do Desempenho/administração & dosagem , Esportes/fisiologia , Adolescente , Fenômenos Fisiológicos da Nutrição do Adolescente , Criança , Feminino , Humanos , Masculino , Futebol/fisiologia , Natação/fisiologia
9.
Temperature (Austin) ; 8(1): 64-79, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33553506

RESUMO

The purpose of this study was to assess autonomic and hemodynamic recovery in women who performed moderate-intensity exercise in heat. Seven women (31.7 ± 7.6 years, 67.5 ± 4.4 kg, 25.7 ± 5.6% Fat, 43.9 ± 5.1 mL/kg/min) completed two identical bouts of graded treadmill walking (~60% VO2peak). One bout was hot (37.5 ± 1.4°C, 46.5 ± 4.6% relative humidity (RH)), and the other was moderate (20.7 ± 1.1°C, 29.9 ± 4.1% RH). For 24 h before and one h after each bout, participants had heart rate variability monitored. After each exercise bout HR and BP were measured during 30 min of supine recovery and 10 min of orthostatic challenge. HF power and RMSSD were lower and LF power and LF:HF ratio greater following exercise in the heat and remained different from the moderate condition for 30 min (p < 0.05). During supine recovery, heat exposure led to higher HR (p = 0.002) and lower DBP (p = 0.016). SBP (p = 0.037) and DBP (p = 0.008) were both lower after 10 min of supine recovery following hot exercise than after moderate temperature. Average response did not reveal orthostatic hypotension despite heat causing a higher HR (p = 0.011) and lower SBP (p = 0.026) after 10 min of orthostatic exposure. Trained women exhibit an autonomic shift toward sympathetic dominance for at least 30 min after exercise in heat. Women who exercise in heat should be wary of an exacerbated HR response after exercise and low recovery blood pressures.

10.
J Strength Cond Res ; 35(3): 804-810, 2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-30234694

RESUMO

ABSTRACT: Zanders, BR, Currier, BS, Harty, PS, Zabriskie, HA, Smith, CR, Stecker, RA, Richmond, SR, Jagim, AR, and Kerksick, CM. Changes in energy expenditure, dietary intake, and energy availability across an entire collegiate women's basketball season. J Strength Cond Res 35(3): 804-810, 2021-The purpose of this study was to identify changes in energy expenditure and dietary intake across an entire women's basketball season. On 5 different occasions across the competitive season, female collegiate basketball players (19.8 ± 1.3 years, 173.9 ± 13.6 cm, 74.6 ± 9.1 kg, 27.1 ± 3.2% fat, 53.9 ± 6.4 ml·kg-1·min-1, n = 13) were outfitted with heart rate and activity monitors over 4 consecutive days and completed 4-day food and fluid records to assess changes in energy expenditure and dietary status. Dual-energy x-ray absorptiometry was used to assess baseline body composition and resting energy expenditure (REE) was measured before and after the season. Data were analyzed using 1-factor repeated-measures analysis of variance. Total daily energy expenditure (TDEE, p = 0.059) and physical activity levels (TDEE/REE, p = 0.060) both tended to decrease throughout the season. Energy balance was negative at all time points throughout the season. Absolute and normalized daily protein intake at the end of the season was significantly (p < 0.05) lower than at the beginning of the season. Carbohydrate (3.7 ± 0.4 g·kg-1·d-1) and protein (1.17 ± 0.16 g·kg-1·d-1) intakes were lower than commonly recommended values based on previously published guidelines. These findings suggest that greater education and interventions for collegiate athletes and coaches regarding dietary intake and energy expenditure are warranted.


Assuntos
Basquetebol , Composição Corporal , Ingestão de Alimentos , Ingestão de Energia , Metabolismo Energético , Feminino , Humanos , Estações do Ano
11.
J Int Soc Sports Nutr ; 17(1): 60, 2020 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-33261645

RESUMO

BACKGROUND: Large (48-g), isonitrogenous doses of rice and whey protein have previously been shown to stimulate similar adaptations to resistance training, but the impact of consuming smaller doses has yet to be compared. We evaluated the ability of 24-g doses of rice or whey protein concentrate to augment adaptations following 8 weeks of resistance training. METHODS: Healthy resistance-trained males (n = 24, 32.8 ± 6.7 years, 179.3 ± 8.5 cm, 87.4 ± 8.5 kg, 27.2 ± 1.9 kg/m2, 27.8 ± 6.0% fat) were randomly assigned and matched according to fat-free mass to consume 24-g doses of rice (n = 12, Growing Naturals, LLC) or whey (n = 12, NutraBio Labs, Inc.) protein concentrate for 8 weeks while completing a standardized resistance training program. Body composition (DXA), muscular strength (one-repetition maximum [1RM]) and endurance (repetitions to fatigue [RTF] at 80% 1RM) using bench press (BP) and leg press (LP) exercises along with anaerobic capacity (Wingate) were assessed before and after the intervention. Subjects were asked to maintain regular dietary habits and record dietary intake every 2 weeks. Outcomes were assessed using 2 × 2 mixed (group x time) factorial ANOVA with repeated measures on time and independent samples t-tests using the change scores from baseline. A p-value of 0.05 and 95% confidence intervals on the changes between groups were used to determine outcomes. RESULTS: No baseline differences (p > 0.05) were found for key body composition and performance outcomes. No changes (p > 0.05) in dietary status occurred within or between groups (34 ± 4 kcal/kg/day, 3.7 ± 0.77 g/kg/day, 1.31 ± 0.28 g/kg/day, 1.87 ± 0.23 g/kg/day) throughout the study for daily relative energy (34 ± 4 kcals/kg/day), carbohydrate (3.7 ± 0.77 g/kg/day), fat (1.31 ± 0.28 g/kg/day), and protein (1.87 ± 0.23 g/kg/day) intake. Significant main effects for time were revealed for body mass (p = 0.02), total body water (p = 0.01), lean mass (p = 0.008), fat-free mass (p = 0.007), BP 1RM (p = 0.02), BP volume (p = 0.04), and LP 1RM (p = 0.01). Changes between groups were similar for body mass (- 0.88, 2.03 kg, p = 0.42), fat-free mass (- 0.68, 1.99 kg, p = 0.32), lean mass (- 0.73, 1.91 kg, p = 0.37), fat mass (- 0.48, 1.02 kg, p = 0.46), and % fat (- 0.63, 0.71%, p = 0.90). No significant between group differences were seen for BP 1RM (- 13.8, 7.1 kg, p = 0.51), LP 1RM (- 38.8, 49.6 kg, p = 0.80), BP RTF (- 2.02, 0.35 reps, p = 0.16), LP RTF (- 1.7, 3.3 reps, p = 0.50), and Wingate peak power (- 72.5, 53.4 watts, p = 0.76) following the eight-week supplementation period. CONCLUSIONS: Eight weeks of daily isonitrogenous 24-g doses of rice or whey protein in combination with an eight-week resistance training program led to similar changes in body composition and performance outcomes. Retroactively registered on as NCT04411173 .


Assuntos
Composição Corporal , Oryza/química , Proteínas de Vegetais Comestíveis/farmacologia , Treinamento de Força/métodos , Proteínas do Soro do Leite/farmacologia , Adulto , Anaerobiose , Composição Corporal/efeitos dos fármacos , Composição Corporal/fisiologia , Água Corporal , Ingestão de Energia , Humanos , Masculino , Força Muscular/fisiologia , Desempenho Físico Funcional , Proteínas de Vegetais Comestíveis/administração & dosagem , Proteínas de Vegetais Comestíveis/química , Fenômenos Fisiológicos da Nutrição Esportiva , Proteínas do Soro do Leite/administração & dosagem , Proteínas do Soro do Leite/química
12.
Front Nutr ; 7: 585900, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33330586

RESUMO

Little is known about the optimal time to consume caffeine prior to exercise to maximize the ergogenic benefits of the substance. Purpose: To determine the optimal pre-exercise time interval to consume caffeine to improve lower-body muscular performance. A secondary aim was to identify the presence of any sex differences in responses to timed caffeine administration. Methods: Healthy, resistance-trained males (n = 18; Mean±SD; Age: 25.1 ± 5.7 years; Height: 178.4 ± 7.1 cm; Body mass: 91.3 ± 13.5 kg; Percent body fat: 20.7 ± 5.2; Average caffeine consumption: 146.6 ± 100.3 mg/day) and females (n = 11; Mean ± SD; Age: 20.1 ± 1.6 years; Height: 165.0 ± 8.8 cm; Body mass: 65.8 ± 10.0 kg; Percent bodyfat: 25.8 ± 4.2; Average caffeine consumption: 111.8 ± 91.7 mg/day) participated in this investigation. In a randomized, double-blind, placebo-controlled, crossover fashion, participants consumed 6 mg·kg-1 caffeine or placebo solution at three time points: 2 h prior (2H), 1 h prior (1H), or 30 min prior (30M) to exercise testing. During three visits, caffeine was randomly administered at one time point, and placebo was administered at the other two time points. During one visit, placebo was administered at all three time points. Next, participants performed isometric mid-thigh pulls (IMTP), countermovement vertical jumps (CMVJ), and isometric/isokinetic knee extensor testing (ISO/ISOK). Results: Caffeine administered at 1H significantly improved absolute CMVJ and ISO performance relative to placebo. Mean CMVJ jump height was significantly higher during 1H compared to 30M. However, only caffeine administered at 30M significantly improved absolute measures of isokinetic performance. Analysis of the pooled caffeine conditions revealed that muscular performance was more consistently augmented by caffeine in males compared to females. Conclusions: Pre-exercise caffeine timing significantly modulated participant responses to the substance, with 1H exerting the most consistent ergogenic benefits relative to other time points, particularly compared to 2H. Male participants were found to respond more consistently to caffeine compared to female participants. These results suggest that active individuals can maximize the ergogenic effects of caffeine by consuming the substance ~1 h prior to the point when peak muscular performance is desired.

13.
Nutr Metab (Lond) ; 17: 93, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33110439

RESUMO

Background: Probiotic Bacillus coagulans GBI-30, 6086 (BC30) has been shown to increase protein digestion in an in vitro model of the stomach and small intestine. Once active in the small intestine after germination, BC30 aids the digestion of carbohydrates and proteins. The extent to which BC30 administration may impact protein digestion and amino acid appearance in humans after protein ingestion is currently unknown. This study examined the impact of adding BC30 to a 25-g dose of milk protein concentrate on post-prandial changes in blood amino acids concentrations. Methods: 14 males and 16 females (n = 30, 26.4 ± 6.5 years; 172.3 ± 10.8 cm; 78.2 ± 14.8 kg; 22.6 ± 7.2% fat) completed two supplementation protocols that each spanned two weeks separated by a washout period that lasted three weeks. Participants were instructed to track their dietary intake and ingest a daily 25-g dose of milk protein concentrate with (MPCBC30) or without (MPC) the addition of BC30. Body composition and demographics were assessed upon arrival to the laboratory. Upon ingestion of their final assigned supplemental dose, blood samples were taken at 0 (baseline), 30, 60, 90, 120, 180, and 240 min post-consumption and analyzed for amino acid concentrations. Results: Arginine (p = 0.03) and Isoleucine (p = 0.05) revealed greater area-under-the curve (AUC) in MPCBC30 group compared to MPC. In addition, Arginine (p = 0.02), Serine (p = 0.01), Ornithine (p = 0.02), Methionine (p = 0.04), Glutamic Acid (p = 0.01), Phenylalanine (p = 0.05), Isoleucine (p = 0.04), Tyrosine (p = 0.02), Essential Amino Acids (p = 0.02), and Total Amino Acids (p < 0.01) all revealed significantly greater concentration maximum (CMax) in MPCBC30 compared to MPC. Finally, time to reach CMax (TMax) was significantly faster for Glutamine (p < 0.01), Citrulline (p < 0.01), Threonine (p = 0.04), Alanine (p = 0.02) in MPCBC30 when compared to MPC. Greater mean differences between groups for AUC and CMax in women when compared to the mean differences in men were found for several amino acids. Conclusion: In concert with previous in vitro evidence of improved protein digestion and amino acid appearance, these results reveal that adding BC30 to protein sources such as milk protein concentrate can improve AUC, CMax, and faster TMax. Follow-up research should examine differences between gender and explore how aging can impact these outcomes. Retrospectively registered on June 11, 2020 at ClinicalTrials.gov as NCT04427020.

14.
Mayo Clin Proc ; 95(8): 1594-1603, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32753134

RESUMO

OBJECTIVE: To examine differences in the frequency and severity of federally reported adverse events between caffeine-containing and non-caffeine-containing products while also identifying the category of caffeine-containing products associated with the highest frequency and severity of adverse events. PATIENTS AND METHODS: All adverse event reports that met specified eligibility criteria and were submitted to the Center for Food Safety and Applied Nutrition Adverse Event Reporting System between January 1, 2014, and June 29, 2018, were extracted. In this retrospective observational study, the most severe adverse event experienced, an ordinal variable, was categorized into death, life-threatening, hospitalization/disability, and emergency department visit. A nonproportional odds model was used to compare the odds of caffeine-containing products being associated with more severe adverse events relative to a noncaffeine group. The analysis is of data only from those reporting adverse events and may or may not be representative of the entire population exposed to these products, which is not known from the examined data. RESULTS: Energy and preworkout products saw a significant increase in the odds of the adverse event experienced being death rather than the other less severe outcomes relative to the noncaffeinated group. Those products, along with weight loss products, had greater odds of the adverse event being death or life-threatening vs the less severe outcomes relative to the noncaffeinated group. CONCLUSION: Caffeine-containing products have a greater association with severe adverse events compared with non-caffeine-containing products. Exposure to preworkout and weight loss products had greater odds of being associated with a more serious adverse event relative to noncaffeinated products. Health care practitioners should use these outcomes to better inform and educate patients about the many factors related to caffeine intake and adverse outcomes.


Assuntos
Sistemas de Notificação de Reações Adversas a Medicamentos/estatística & dados numéricos , Cafeína/efeitos adversos , United States Food and Drug Administration , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Fármacos Antiobesidade/efeitos adversos , Fármacos Antiobesidade/toxicidade , Cafeína/toxicidade , Bebidas Gaseificadas/efeitos adversos , Bebidas Gaseificadas/toxicidade , Criança , Pré-Escolar , Café/efeitos adversos , Suplementos Nutricionais/efeitos adversos , Suplementos Nutricionais/toxicidade , Feminino , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Chá/efeitos adversos , Estados Unidos , Adulto Jovem
15.
Nutrients ; 12(8)2020 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-32727162

RESUMO

Fish oils (FOs) are rich in omega-3 long-chain polyunsaturated fatty acids, which have been purported to enhance recovery of muscular performance and reduce soreness post-exercise. However, the most effective FO dose for optimizing recovery remains unclear. The purpose of this investigation was to examine the effect of FO supplementation dosing on the recovery of measures of muscular performance, perceived soreness, and markers of muscle damage following a rigorous bout of eccentric exercise. Thirty-two college-aged resistance-trained males (~23.6 years, 71.6 kg, 172.1 cm) were supplemented with 2, 4, 6 g/day (G) FO or placebo (PL) for ~7.5 weeks. Following 7 weeks of supplementation, pre-exercise (PRE) performance assessments of vertical jump (VJ), knee extensor strength, 40-yard sprint, T-test agility, and perceived soreness were completed prior to a bout of muscle-damaging exercise and were repeated immediately post (IP), 1-, 2-, 4-, 24-, 48-, and 72-h (H) post-exercise. Repeated measures analysis of variance indicated a treatment × time interaction (p < 0.001) for VJ and perceived soreness, but no group differences were observed at any time point. VJ returned to PRE (54.8 ± 7.9 cm) by 1H (51.8 ± 6.5 cm, p = 0.112) for 6G, while no other groups returned to baseline until 48H. Lower soreness scores were observed in 6G compared to PL at 2H (mean difference [MD] = 2.74, p = 0.046), at 24H (MD: 3.45, p < 0.001), at 48H (MD = 4.45, p < 0.001), and at 72H (MD = 3.00, p = 0.003). Supplementation with 6G of FO optimized the recovery of jump performance and muscle soreness following a damaging bout of exercise.


Assuntos
Suplementos Nutricionais , Exercício Físico/fisiologia , Ácidos Graxos Ômega-3/administração & dosagem , Óleos de Peixe/administração & dosagem , Mialgia/etiologia , Relação Dose-Resposta a Droga , Método Duplo-Cego , Humanos , Joelho/fisiologia , Masculino , Força Muscular/efeitos dos fármacos , Músculo Esquelético/efeitos dos fármacos , Treinamento de Força , Fenômenos Fisiológicos da Nutrição Esportiva , Adulto Jovem
16.
J Int Soc Sports Nutr ; 17(1): 24, 2020 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-32398103

RESUMO

The microorganisms in the gastrointestinal tract play a significant role in nutrient uptake, vitamin synthesis, energy harvest, inflammatory modulation, and host immune response, collectively contributing to human health. Important factors such as age, birth method, antibiotic use, and diet have been established as formative factors that shape the gut microbiota. Yet, less described is the role that exercise plays, particularly how associated factors and stressors, such as sport/exercise-specific diet, environment, and their interactions, may influence the gut microbiota. In particular, high-level athletes offer remarkable physiology and metabolism (including muscular strength/power, aerobic capacity, energy expenditure, and heat production) compared to sedentary individuals, and provide unique insight in gut microbiota research. In addition, the gut microbiota with its ability to harvest energy, modulate the immune system, and influence gastrointestinal health, likely plays an important role in athlete health, wellbeing, and sports performance. Therefore, understanding the mechanisms in which the gut microbiota could play in the role of influencing athletic performance is of considerable interest to athletes who work to improve their results in competition as well as reduce recovery time during training. Ultimately this research is expected to extend beyond athletics as understanding optimal fitness has applications for overall health and wellness in larger communities. Therefore, the purpose of this narrative review is to summarize current knowledge of the athletic gut microbiota and the factors that shape it. Exercise, associated dietary factors, and the athletic classification promote a more "health-associated" gut microbiota. Such features include a higher abundance of health-promoting bacterial species, increased microbial diversity, functional metabolic capacity, and microbial-associated metabolites, stimulation of bacterial abundance that can modulate mucosal immunity, and improved gastrointestinal barrier function.


Assuntos
Desempenho Atlético/fisiologia , Dieta , Exercício Físico/fisiologia , Microbioma Gastrointestinal/fisiologia , Humanos , Fenômenos Fisiológicos da Nutrição Esportiva
17.
J Diet Suppl ; 17(5): 561-586, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32456572

RESUMO

We determined the effects of a commercially available, GRAS (Generally Recognized As Safe) by independent conclusion, CBD-containing hemp oil extract on stress resilience, perceived recovery, mood, affect, body composition, and clinical safety markers in healthy human subjects.Methods: Using a randomized, placebo-controlled, double-blind design, 65 overweight, but otherwise healthy men and women (35.2 ± 11.4 years, 28.5 ± 3.3 kg/m2) ingested either Hemp Oil Extract [Hemp, 60 mg/d PlusCBDTM Extra Strength Hemp Extract Oil (15 mg hemp-derived CBD)] or a placebo (PLA) every day for six weeks while continuing to follow their normal diet and physical activity patterns. Outcome variables included changes in stress resilience, a 14-item panel of various psychometric parameters, heart-rate variability, plasma chromogranin A, body composition, and general markers of health. Data were analyzed using mixed factorial ANOVA, t-tests with 95% confidence intervals, and effect sizes (ES).Results: HDL cholesterol significantly improved in the Hemp group (p = 0.004; ES = 0.75). No other statistically significant group x time interaction effects were observed. Statistical tendencies for between-group differences were found for 'I Get Pleasure From Life' (p = 0.06, ES = 0.48) and 'Ability to Cope with Stress' (p = 0.07, ES = 0.46). Sleep quality (Hemp, p = 0.005, ES = 0.54) and sleep quantity (Hemp, p = 0.01, ES = 0.58) exhibited significant within-group changes. All values for hepato-renal function, cardiovascular health, fasting blood lipids, and whole blood cell counts remained within normal clinical limits with no between-group differences over time being identified.Conclusions: Hemp supplementation improved HDL cholesterol, tended to support psychometric measures of perceived sleep, stress response, and perceived life pleasure and was well tolerated with no clinically relevant safety concerns. Registered at clinicaltrials.gov: NCT04294706.


Assuntos
Cannabis , Suplementos Nutricionais , Sobrepeso/tratamento farmacológico , Extratos Vegetais/administração & dosagem , Resiliência Psicológica/efeitos dos fármacos , Adaptação Psicológica/efeitos dos fármacos , Adulto , Análise de Variância , Biomarcadores/sangue , Composição Corporal/efeitos dos fármacos , HDL-Colesterol/sangue , Cromogranina A/sangue , Método Duplo-Cego , Feminino , Voluntários Saudáveis , Frequência Cardíaca/efeitos dos fármacos , Humanos , Masculino , Sobrepeso/sangue , Sobrepeso/psicologia , Psicometria , Sono/efeitos dos fármacos , Estresse Fisiológico/efeitos dos fármacos
18.
Nutrients ; 12(4)2020 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-32325856

RESUMO

Aerobic exercise and thermal stress instigate robust challenges to the immune system. Various attempts to modify or supplement the diet have been proposed to bolster the immune system responses. The purpose of this study was to identify the impact of yeast beta-glucan (Saccharomyces cerevisiae) supplementation on exercise-induced muscle damage and inflammation. Healthy, active men (29.6 ± 6.7 years, 178.1 ± 7.2 cm, 83.2 ± 11.2 kg, 49.6 ± 5.1 mL/kg/min, n = 16) and women (30.1 ± 8.9 years, 165.6 ± 4.1 cm, 66.7 ± 10.0 kg, 38.7 ± 5.8 mL/kg/min, n = 15) were randomly assigned in a double-blind and cross-over fashion to supplement for 13 days with either 250 mg/day of yeast beta-glucan (YBG) or a maltodextrin placebo (PLA). Participants arrived fasted and completed a bout of treadmill exercise at 55% peak aerobic capacity (VO2Peak) in a hot (37.2 ± 1.8 °C) and humid (45.2 ± 8.8%) environment. Prior to and 0, 2, and 72 h after completing exercise, changes in white blood cell counts, pro- and anti-inflammatory cytokines, markers of muscle damage, markers of muscle function, soreness, and profile of mood states (POMS) were assessed. In response to exercise and heat, both groups experienced significant increases in white blood cell counts, plasma creatine kinase and myoglobin, and soreness along with reductions in peak torque and total work with no between-group differences. Concentrations of serum pro-inflammatory cytokines in YBG were lower than PLA for macrophage inflammatory protein 1ß (MIP-1ß) (p = 0.044) and tended to be lower for interleukin 8 (IL-8) (p = 0.079), monocyte chemoattractment protein 1 (MCP-1) (p = 0.095), and tumor necrosis factor α (TNF-α) (p = 0.085). Paired samples t-tests using delta values between baseline and 72 h post-exercise revealed significant differences between groups for IL-8 (p = 0.044, 95% Confidence Interval (CI): (0.013, 0.938, d = -0.34), MCP-1 (p = 0.038, 95% CI: 0.087, 2.942, d = -0.33), and MIP-1ß (p = 0.010, 95% CI: 0.13, 0.85, d = -0.33). POMS outcomes changed across time with anger scores in PLA exhibiting a sharper decline than YBG (p = 0.04). Vigor scores (p = 0.04) in YBG remained stable while scores in PLA were significantly reduced 72 h after exercise. In conclusion, a 13-day prophylactic period of supplementation with 250 mg of yeast-derived beta-glucans invoked favorable changes in cytokine markers of inflammation after completing a prolonged bout of heated treadmill exercise.


Assuntos
Suplementos Nutricionais , Regulação para Baixo/efeitos dos fármacos , Teste de Esforço , Exercício Físico/fisiologia , Resposta ao Choque Térmico/genética , Resposta ao Choque Térmico/fisiologia , Inflamação/genética , Inflamação/metabolismo , Fenômenos Fisiológicos da Nutrição/fisiologia , Saccharomyces cerevisiae/química , beta-Glucanas/administração & dosagem , beta-Glucanas/farmacologia , Adulto , Quimiocina CCL2/metabolismo , Quimiocina CCL4/metabolismo , Estudos Cross-Over , Método Duplo-Cego , Feminino , Humanos , Mediadores da Inflamação/metabolismo , Contagem de Leucócitos , Masculino , Fadiga Muscular/efeitos dos fármacos , Fadiga Muscular/genética , Fator de Necrose Tumoral alfa/metabolismo , Adulto Jovem , beta-Glucanas/isolamento & purificação
19.
Nutrients ; 12(3)2020 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-32156010

RESUMO

Vitamin D and calcium supplementation have been posited to improve body composition and different formulations of calcium may impact bioavailability. However, data are lacking regarding the combinatorial effects of exercise, diet, and calcium and/or vitamin D supplementation on body composition changes in post-menopausal women. Herein, 128 post-menopausal women (51.3 ± 4.5 years, 36.4 ± 5.7 kg/m2, 46.2 ± 4.5% fat) were assigned to diet and supplement groups while participating in a supervised circuit-style resistance-training program (3 d/week) over a 14-week period. Diet groups included: (1) normal diet (CTL), (2) a low-calorie, higher protein diet (LCHP; 1600 kcal/day, 15% carbohydrates, 55% protein, 30% fat), and (3) a low-calorie, higher carbohydrate diet (LCHC; 1600 kcal/day, 55% carbohydrates, 15% protein, 30% fat). Supplement groups consisted of: (1) maltodextrin (PLA), (2) 800 mg/day of calcium carbonate (Ca), and (3) 800 mg/day of calcium citrate and malate and 400 IU/day of vitamin D (Ca+D). Fasting blood samples, body composition, resting energy expenditure, aerobic capacity, muscular strength and endurance measures were assessed. Data were analyzed by mixed factorial ANOVA with repeated measures and presented as mean change from baseline [95% CI]. Exercise training promoted significant improvements in strength, peak aerobic capacity, and blood lipids. Dieting resulted in greater losses of body mass (CTL -0.4 ± 2.4; LCHC -5.1 ± 4.2; LCHP -3.8 ± 4.2 kg) and fat mass (CTL -1.4 ± 1.8; LCHC -3.7 ± 3.7; LCHP -3.4 ± 3.4 kg). When compared to LCHC-PLA, the LCHC + Ca combination led to greater losses in body mass (PLA -4.1 [-6.1, -2.1], Ca -6.4 [-8.1, -4.7], Ca+D -4.4 [-6.4, -2.5] kg). In comparison to LCHC-Ca, the LCHC-Ca+D led to an improved maintenance of fat-free mass (PLA -0.3 [-1.4, 0.7], Ca -1.4 [-2.3, -0.5], Ca+D 0.4 [-0.6, 1.5] kg) and a greater loss of body fat (PLA -2.3 [-3.4, -1.1], Ca -1.3 [-2.3, -0.3], Ca+D -3.6 [-4.8, -2.5]%). Alternatively, no significant differences in weight loss or body composition resulted when adding Ca or Ca+D to the LCHP regimen in comparison to when PLA was added to the LCHP diet. When combined with an energy-restricted, higher carbohydrate diet, adding 800 mg of Ca carbonate stimulated greater body mass loss compared to when a PLA was added. Alternatively, adding Ca+D to the LCHC diet promoted greater% fat changes and attenuation of fat-free mass loss. Our results expand upon current literature regarding the impact of calcium supplementation with dieting and regular exercise. This data highlights that different forms of calcium in combination with an energy restricted, higher carbohydrate diet may trigger changes in body mass or body composition while no impact of calcium supplementation was observed when participants followed an energy restricted, higher protein diet.


Assuntos
Composição Corporal , Cálcio/administração & dosagem , Restrição Calórica , Suplementos Nutricionais , Exercício Físico/fisiologia , Fenômenos Fisiológicos da Nutrição/fisiologia , Pós-Menopausa/fisiologia , Vitamina D/administração & dosagem , Adulto , Índice de Massa Corporal , Carboidratos da Dieta/administração & dosagem , Feminino , Humanos , Pessoa de Meia-Idade , Treinamento de Força , Fatores de Tempo
20.
J Funct Morphol Kinesiol ; 5(4)2020 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-33467292

RESUMO

This case study examined changes in body composition, resting metabolic rate (RMR), aerobic capacity, and daily physical activity in a patient who had ulcerative colitis and underwent ileal pouch-anal anastomosis (IPAA) surgery. Body composition, RMR, and peak oxygen consumption (VO2peak) were assessed prior to surgery and four, eight, and 16 weeks after IPAA surgery. Daily physical activity data were extracted from a wrist-worn activity tracker preoperatively and 16 months postoperatively. At baseline, total body mass was 95.3 kg; body fat, 11.6%; lean body mass, 81.1 kg; RMR, 2416 kcal/d; and VO2peak, 42.7 mL/kg/min. All values decreased from baseline at four weeks postoperatively, body mass was 85.2 kg (-10.5%); body fat, 10.9% (-6.0%); lean body mass, 73.1 kg (-9.9%); RMR 2210 kcal/d (-8.5%) and VO2peak, 25.5 mL/kg/min (-40.3%). At 16 weeks postoperatively, most parameters were near their baseline levels (within 1-7%), exceptions were VO2peak, which was 20.4% below baseline, and RMR, which increased to nearly 20% above baseline. After the patient had IPAA surgery, his total and lean body masses, RMR, and aerobic capacity were markedly decreased. Daily physical activity decreased postoperatively and likely contributed to the decreased aerobic capacity, which may take longer to recover compared to body composition and RMR parameters.

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