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1.
J Int Soc Sports Nutr ; 18(1): 4, 2021 Jan 07.
Artículo en Inglés | MEDLINE | ID: mdl-33413462

RESUMEN

BACKGROUND: The effects of ingesting varying essential amino acid (EAA)/protein-containing food formats on protein kinetics during energy deficit are undetermined. Therefore, recommendations for EAA/protein food formats necessary to optimize both whole-body protein balance and muscle protein synthesis (MPS) during energy deficit are unknown. We measured protein kinetics after consuming iso-nitrogenous amounts of free-form essential amino acid-enriched whey (EAA + W; 34.7 g protein, 24 g EAA sourced from whey and free-form EAA), whey (WHEY; 34.7 g protein, 18.7 g EAA), or a mixed-macronutrient meal (MEAL; 34.7 g protein, 11.4 g EAA) after exercise during short-term energy deficit. METHODS: Ten adults (mean ± SD; 21 ± 4 y; 25.7 ± 1.7 kg/m2) completed a randomized, double-blind crossover study consisting of three, 5 d energy-deficit periods (- 30 ± 3% of total energy requirements), separated by 14 d. Whole-body protein synthesis (PS), breakdown (PB), and net balance (NET) were determined at rest and in response to combination exercise consisting of load carriage treadmill walking, deadlifts, and box step-ups at the end of each energy deficit using L-[2H5]-phenylalanine and L-[2H2]-tyrosine infusions. Treatments were ingested immediately post-exercise. Mixed-muscle protein synthesis (mixed-MPS) was measured during exercise through recovery. RESULTS: Change (Δ postabsorptive + exercise to postprandial + recovery [mean treatment difference (95%CI)]) in whole-body (g/180 min) PS was 15.8 (9.8, 21.9; P = 0.001) and 19.4 (14.8, 24.0; P = 0.001) greater for EAA + W than WHEY and MEAL, respectively, with no difference between WHEY and MEAL. ΔPB was - 6.3 (- 11.5, - 1.18; P = 0.02) greater for EAA + W than WHEY and - 7.7 (- 11.9, - 3.6; P = 0.002) greater for MEAL than WHEY, with no difference between EAA + W and MEAL. ΔNET was 22.1 (20.5, 23.8; P = 0.001) and 18.0 (16.5, 19.5; P = 0.00) greater for EAA + W than WHEY and MEAL, respectively, while ΔNET was 4.2 (2.7, 5.6; P = 0.001) greater for MEAL than WHEY. Mixed-MPS did not differ between treatments. CONCLUSIONS: While mixed-MPS was similar across treatments, combining free-form EAA with whey promotes greater whole-body net protein balance during energy deficit compared to iso-nitrogenous amounts of whey or a mixed-macronutrient meal. TRIAL REGISTRATION: ClinicalTrials.gov, Identifier no. NCT04004715 . Retrospectively registered 28 June 2019, first enrollment 6 June 2019.


Asunto(s)
Aminoácidos Esenciales/metabolismo , Ejercicio Físico/fisiología , Nutrientes/metabolismo , Periodo Posprandial , Proteínas/metabolismo , Suero Lácteo/metabolismo , Adulto , Aminoácidos Esenciales/administración & dosificación , Aminoácidos Esenciales/sangre , Índice de Masa Corporal , Estudios Cruzados , Proteínas en la Dieta/administración & dosificación , Proteínas en la Dieta/metabolismo , Método Doble Ciego , Ingestión de Energía , Femenino , Alimentos Fortificados , Humanos , Insulina/sangre , Masculino , Comidas , Proteínas Musculares/biosíntesis , Nutrientes/administración & dosificación , Fenilalanina/administración & dosificación , Factores de Tiempo , Tirosina/administración & dosificación , Suero Lácteo/administración & dosificación , Suero Lácteo/química , Adulto Joven
2.
J Diet Suppl ; 18(2): 147-168, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-32138563

RESUMEN

Introduction: ß-alanine (BA) supplementation may improve cognition and mitigate symptoms of anxiety and depression associated with aging, neurological disorders, and physical exertion, which has been attributed to increases in brain carnosine and/or brain-derived neurotropic factor (BDNF). BA also provides beneficial effects on cognition, mood, and physical performance during military operations; however, whether BA can attenuate mood disruptions and cognitive dysfunction associated with the anticipatory stress prior to simulated military operations is unknown.Purpose: The present study examined the effects of 14 days of BA (12 g·day-1) supplementation on cognitive function, mood, and circulating BDNF concentrations in recreationally-active, healthy males with limited inflammation and oxidative stress prior to a 24h simulated military operation.Methods: Participants were randomized into BA (n = 10) or placebo (n = 9; PL) for 14 days. Cognitive function, mood, and circulating BDNF were assessed before (PRE) and after (POST) supplementation. Cognition was assessed via multiple object tracking (Neurotracker™), visuomotor reaction time (Dynavision™), mathematical processing (Serial Subtraction Test), and neuropsychological assessments (ANAM™). Mood was assessed using the Profile of Mood States (POMS) questionnaire. After POST testing, subjects underwent a 24h simulated military operation.Results: No change in measures of cognitive function or BDNF concentrations were observed (p > 0.05). However, BA experienced significant reductions (p = 0.046) in subjective feelings of depression, while PL experienced significant reductions (p = 0.021) in feelings of vigor from PRE to POST.Conclusions: High-dose, short-duration BA supplementation does not appear to affect cognitive function or circulating BDNF, but may mitigate the onset of negative mood states in healthy, recreationally-active males prior to a simulated military operation.


Asunto(s)
Afecto/efectos de los fármacos , Factor Neurotrófico Derivado del Encéfalo , Cognición , Personal Militar , Estrés Psicológico , beta-Alanina/administración & dosificación , Encéfalo , Factor Neurotrófico Derivado del Encéfalo/sangre , Cognición/efectos de los fármacos , Suplementos Dietéticos , Humanos , Masculino
3.
J Strength Cond Res ; 34(11): 3042-3054, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-33105353

RESUMEN

Wells, AJ, Varanoske, AN, Coker, NA, Kozlowski, GJ, Frosti, CL, Boffey, D, Harat, I, Jahani, S, Gepner, Y, and Hoffman, JR. Effect of ß-alanine supplementation on monocyte recruitment and cognition during a 24-hour simulated military operation. J Strength Cond Res 34(11): 3042-3054, 2020-Sustained military operations (SUSOPs) result in psychological stress and cognitive dysfunction, which may be related to the recruitment of classical monocytes into the brain. This study examined the effect of beta-alanine (BA) on cognition and monocyte recruitment during a simulated 24-hour SUSOP. Nineteen healthy men ingested 12-g/d BA or placebo for 14 days before an SUSOP. Monocyte chemoattractant protein-1 (MCP-1), C-C chemokine receptor-2 (CCR2), and macrophage-1-antigen (CD11b) expression were assessed through multiplex assay and flow cytometry. Psychological stress and cognition were assessed through Automated Neuropsychological Assessment Metrics (ANAM). A composite measure of cognition (COGcomp) was generated from throughput scores extracted from 7 ANAM cognitive tests. Assessments occurred at baseline (0H), 12 hours (12H), 18 hours (18H), and 24 hours (24H). Significance was accepted at p ≤ 0.05. No significant effect of BA was noted for any variable (p's > 0.05). The frequency and severity of symptoms of psychological stress increased significantly at 18 and 24H compared with 0 and 12H (p's < 0.05). COGcomp decreased significantly at 18 and 24H compared with 0 and 12H (p's ≤ 0.001). MCP-1 peaked at 18H was significantly lower at 24H compared with 18H but remained elevated at 24H compared with 0H (p's < 0.001). CCR2 expression was significantly lower at 12 (p = 0.031), 18, and 24H (p's < 0.001). CD11b expression was significantly higher at 12H (p = 0.039) and 24H (p's = 0.003). MCP-1 was negatively associated with COGcomp (ß = -0.395, p = 0.002, r2 = 0.174). Neither CCR2 or CD11b was related to COGcomp (p's > 0.05). Cognitive dysfunction during SUSOPs is related to serum concentrations of MCP-1 but is not influenced by BA supplementation.


Asunto(s)
Cognición/efectos de los fármacos , Personal Militar , Monocitos/efectos de los fármacos , Estrés Psicológico/fisiopatología , beta-Alanina/farmacología , Adulto , Quimiocina CCL2/biosíntesis , Suplementos Dietéticos , Método Doble Ciego , Humanos , Antígeno de Macrófago-1/biosíntesis , Masculino , Monocitos/inmunología , Receptores CCR2/biosíntesis , Entrenamiento Simulado/métodos , Estrés Psicológico/epidemiología , Adulto Joven
4.
Amino Acids ; 51(1): 49-60, 2019 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-30003336

RESUMEN

ß-alanine supplementation increases muscle carnosine content and improves anaerobic exercise performance by enhancing intracellular buffering capacity. ß-alanine ingestion in its traditional rapid-release formulation (RR) is associated with the symptoms of paresthesia. A sustained-release formulation (SR) of ß-alanine has been shown to circumvent paresthesia and extend the period of supply to muscle for carnosine synthesis. The purpose of this investigation was to compare 28 days of SR and RR formulations of ß-alanine (6 g day-1) on changes in carnosine content of the vastus lateralis and muscle fatigue. Thirty-nine recreationally active men and women were assigned to one of the three groups: SR, RR, or placebo (PLA). Participants supplementing with SR and RR formulations increased muscle carnosine content by 50.1% (3.87 mmol kg-1ww) and 37.9% (2.62 mmol kg-1ww), respectively. The change in muscle carnosine content in participants consuming SR was significantly different (p = 0.010) from those consuming PLA, but no significant difference was noted between RR and PLA (p = 0.077). Although participants ingesting SR experienced a 16.4% greater increase in muscle carnosine than RR, fatigue during maximal voluntary isometric contractions was significantly attenuated in both SR and RR compared to PLA (p = 0.002 and 0.024, respectively). Symptoms of paresthesia were significantly more frequent in RR compared to SR, the latter of which did not differ from PLA. Results of this study demonstrated that only participants consuming the SR formulation experienced a significant increase in muscle carnosine. Differences in the muscle carnosine response between these formulations may have practical significance for athletic populations in which small changes may have important implications on performance.


Asunto(s)
Carnosina/biosíntesis , Preparaciones de Acción Retardada/administración & dosificación , Suplementos Dietéticos , Músculo Esquelético/efectos de los fármacos , Parestesia/prevención & control , beta-Alanina/administración & dosificación , Adulto , Carnosina/agonistas , Método Doble Ciego , Esquema de Medicación , Ejercicio Físico , Femenino , Humanos , Contracción Isométrica/efectos de los fármacos , Masculino , Fatiga Muscular/efectos de los fármacos , Fatiga Muscular/fisiología , Músculo Esquelético/metabolismo , Músculo Esquelético/fisiología , Parestesia/metabolismo , Parestesia/fisiopatología
5.
Res Sports Med ; 27(2): 204-218, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30348016

RESUMEN

ß-Hydroxy-ß-Methylbutyrate (HMB) is a metabolite of the branched-chain amino acid leucine and its ketoacid α-ketoisocaproate. HMB has been widely used as an ergogenic supplement to increase muscle strength, muscle hypertrophy and enhance recovery. The physiological mechanisms that underlie these benefits are related to HMB's ability to stimulate muscle protein synthesis and minimize muscle breakdown. Although evidence supporting the benefits of HMB supplementation is not conclusive, many of these studies have suffered from methodological flaws including different formulations, supplement duration and population studied. HMB in its free acid formulation is suggestive of having a greater potential for efficacy in both trained and untrained populations than its calcium-salt form. However, the evidence regarding HMB's role in limiting muscle degradation and increasing muscle protein synthesis has created an exciting interest in examining its efficacy among untrained individuals. Recent investigations examining intense training have demonstrated efficacy in maintaining muscle mass and attenuating the inflammatory response.


Asunto(s)
Rendimiento Atlético/fisiología , Músculo Esquelético/efectos de los fármacos , Fenómenos Fisiológicos en la Nutrición Deportiva/efectos de los fármacos , Fenómenos Fisiológicos en la Nutrición Deportiva/fisiología , Valeratos/administración & dosificación , Aminoácidos Esenciales/administración & dosificación , Atletas , Composición Corporal/efectos de los fármacos , Suplementos Dietéticos , Humanos , Leucina/administración & dosificación , Desarrollo de Músculos/efectos de los fármacos , Fuerza Muscular/efectos de los fármacos
6.
Physiol Rep ; 6(24): e13938, 2018 12.
Artículo en Inglés | MEDLINE | ID: mdl-30565426

RESUMEN

Sustained military operations (SUSOPs) are associated with performance decrements and cognitive dysfunction. ß-Alanine (BA) supplementation may have a role in increasing soldier resiliency by enhancing muscle-buffering capacity and reducing oxidative stress. The purpose of this study was to examine the effects of BA on physical performance, cognition, endocrine function, and inflammation during a 24 h simulated SUSOP. Nineteen males were randomized into one of two groups: BA (n = 10) or placebo (n = 9; PLA) (12 g/day) for 14 days preceding the 24 h SUSOP. Assessments were performed at 0 h (0H), 12 h (12H), and 24 h (24H) during the SUSOP. No changes in visual tracking ability, jump power, or upper-body muscular endurance were observed between groups or time points (P's > 0.05). Increases in subjective feelings of soreness and fatigue were noted at 12H compared to 0H (P < 0.05) in PLA, but not in BA. Visual reaction time for PLA was slower at 24H compared to 0H (P = 0.035), and PLA made more errors on reaction time testing at 12H compared to BA (P = 0.048), but motor reaction time was faster (P = 0.016) for PLA. Simulated litter carry and 1 km run completion times increased at 24H compared to 0H in both groups (P < 0.05), however, PLA had a longer 1 km time compared to BA at 24H (P = 0.050). Increases in inflammatory and endocrine markers were observed over the SUSOP, with no differences between groups. BA supplementation appears to maintain some aspects of cognition and physical performance during a 24 h SUSOP, with no effects on endocrine function or inflammation.


Asunto(s)
Antiinflamatorios/farmacología , Cognición/efectos de los fármacos , Hidrocortisona/sangre , Personal Militar , Resistencia Física/efectos de los fármacos , Testosterona/sangre , beta-Alanina/farmacología , Adolescente , Adulto , Antiinflamatorios/administración & dosificación , Humanos , Masculino , Fatiga Muscular/efectos de los fármacos , beta-Alanina/administración & dosificación
7.
Med Sci Sports Exerc ; 50(11): 2231-2241, 2018 11.
Artículo en Inglés | MEDLINE | ID: mdl-29957728

RESUMEN

PURPOSE: To examine the impact of polyphenol supplementation on the recruitment, mobilization, and activation of monocyte subsets after resistance exercise. METHODS: Thirty-eight recreationally active males (22.1 ± 3.1 yr; 173.9 ± 7.9 cm; 77.8 ± 14.5 kg) were assigned to 28 d of polyphenol blend (PPB) supplementation, placebo (PL), or control (CON). Blood samples were obtained before (PRE) postresistance exercise, immediately (IP) postresistance exercise, 1 h (1H) postresistance exercise, 5 h (5H) postresistance exercise, 24 h (24H) postresistance exercise, and 48 h (48H) postresistance exercise (PPB/PL) or rest (CON). Fine-needle biopsies were obtained from the vastus lateralis at PRE, 1H, 5H, and 48H. Circulating concentrations of macrophage chemoattractant protein-1 (MCP-1) and fractalkine, as well as intramuscular MCP-1 were analyzed via multiplex assay. Changes in the proportions and expression of CD11b on monocyte subsets were assessed via flow cytometry. RESULTS: Circulating MCP-1 increased in PPB and PL at IP with further increases at 5H. Intramuscular MCP-1 was increased at 1H, 5H, and 48H in all groups. Classical monocyte proportions were reduced in PPB and PL at IP, and increased at 1H. Nonclassical monocytes were increased in PPB and PL at IP, whereas intermediate monocytes were increased at IP, and reduced at 1H. Intermediate monocytes were increased in PPB at 24H and 48H. CD11b expression was reduced on PPB compared with PL and CON at PRE on intermediate and nonclassical monocytes. CONCLUSIONS: Resistance exercise may elicit selective mobilization of intermediate monocytes at 24H and 48H, which may be mediated by tissue damage. Additionally, polyphenol supplementation may suppress CD11b expression on monocyte subsets at rest.


Asunto(s)
Antioxidantes/administración & dosificación , Suplementos Dietéticos , Monocitos/metabolismo , Polifenoles/administración & dosificación , Músculo Cuádriceps/metabolismo , Entrenamiento de Fuerza , Antígeno CD11b/sangre , Quimiocina CCL2/sangre , Quimiocina CCL2/metabolismo , Quimiocina CX3CL1/sangre , Humanos , Antígeno de Macrófago-1/sangre , Masculino , Factores de Tiempo , Adulto Joven
8.
Nutr Res ; 48: 16-25, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-29246277

RESUMEN

ß-Alanine (BA) supplementation results in elevated intramuscular carnosine content, enhancing buffering capacity during intense exercise. Although men have greater muscle carnosine content than women, elevations still appear to occur despite high baseline levels. Recent research has suggested that BA supplementation may also reduce muscle l-histidine. Thus, the purpose of this investigation was to compare 28 days of BA (6 g·d-1) supplementation in men and women on performance and muscle carnosine, l-histidine, and BA. We hypothesized that supplementation would result in similar elevations in carnosine and performance between sexes and decrease l-histidine. Twenty-six men and women were assigned either BA or placebo (PLA). At baseline, a trend toward greater carnosine (P = .069) was observed in men, and intramuscular BA content was significantly (P ≤ .05) greater in men. Statistical analysis was performed using magnitude-based inferences. Changes in muscle carnosine were likely and very likely greater after BA supplementation compared with PLA in men and women, respectively, but changes were unclear between sexes (mean sex difference: 2.50 ± 4.30 mmol·kg-1 ww). The attenuation of exercise fatigue was likely greater in BA compared with PLA, but the change was unclear between sexes (mean sex difference: 14.0 ± 39.0 Nm). Changes in muscle BA following supplementation was unclear in men, likely elevated in women, but unclear between sexes (mean sex difference: 0.03 ± 0.42 mmol·kg-1 ww). Changes in muscle l-histidine were unclear in men and women, and unclear between sexes (mean sex difference: 0.09 ± 0.13 mmol·kg-1 ww). In conclusion, BA supplementation increased muscle carnosine and attenuated fatigue in men and women similarly but did not reduce muscle l-histidine.


Asunto(s)
Carnosina/metabolismo , Suplementos Dietéticos , Fatiga/tratamiento farmacológico , Histidina/metabolismo , Músculo Esquelético/efectos de los fármacos , beta-Alanina/administración & dosificación , Adulto , Ejercicio Físico , Femenino , Humanos , Masculino , Músculo Esquelético/metabolismo , Encuestas y Cuestionarios , Adulto Joven
9.
J Am Coll Nutr ; 36(8): 608-616, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28910200

RESUMEN

OBJECTIVE: ß-alanine (BA) is a nonproteogenic amino acid that combines with histidine to form carnosine. The amount taken orally in individual doses, however, is limited due to symptoms of paresthesia that are associated with higher doses. The use of a sustained-release formulation has been reported to reduce the symptoms of paresthesia, suggesting that a greater daily dose may be possible. The purpose of the present study was to determine whether increasing the daily dose of BA can result in a similar increase in muscle carnosine in a reduced time. METHODS: Eighteen men and twelve women were randomized into either a placebo (PLC), 6-g BA (6G), or 12-g BA (12G) groups. PLC and 6G were supplemented for 4 weeks, while 12G was supplemented for 2 weeks. A resting blood draw and muscle biopsy were obtained prior to (PRE) and following (POST) supplementation. Plasma and muscle metabolites were measured by high-performance liquid chromatography. The loss in peak torque (ΔPT) was calculated from maximal isometric contractions before and after 250 isokinetic kicks at 180°·sec-1 PRE and POST. RESULTS: Both 12G (p = 0.026) and 6G (p = 0.004) increased muscle carnosine compared to PLC. Plasma histidine was decreased from PRE to POST in 12G compared to PLC (p = 0.002) and 6G (p = 0.001), but no group x time interaction (p = 0.662) was observed for muscle histidine. No differences were observed for any hematological measure (e.g., complete blood counts) or in symptoms of paresthesia among the groups. Although no interaction was noted in ΔPT, a trend (p = 0.073) was observed. CONCLUSION: Results of this investigation indicate that a BA supplementation protocol of 12 g/d-1, using a sustained-release formulation, can accelerate the increase in carnosine content in skeletal muscle while attenuating paresthesia.


Asunto(s)
Carnosina/metabolismo , Suplementos Dietéticos , Músculo Esquelético/efectos de los fármacos , Fenómenos Fisiológicos en la Nutrición Deportiva , beta-Alanina/administración & dosificación , Adulto , Dieta , Carbohidratos de la Dieta/administración & dosificación , Grasas de la Dieta/administración & dosificación , Proteínas en la Dieta/administración & dosificación , Relación Dosis-Respuesta a Droga , Ejercicio Físico , Femenino , Histidina/sangre , Humanos , Masculino , Músculo Esquelético/metabolismo , Evaluación Nutricional , Parestesia/tratamiento farmacológico , Cooperación del Paciente , Encuestas y Cuestionarios , Adulto Joven , beta-Alanina/sangre
10.
Amino Acids ; 49(8): 1415-1426, 2017 08.
Artículo en Inglés | MEDLINE | ID: mdl-28555251

RESUMEN

Attenuating TNFα/TNFr1 signaling in monocytes has been proposed as a means of mitigating inflammation. The purpose of this study was to examine the effects of a milk protein supplement on TNFα and monocyte TNFr1 expression. Ten resistance-trained men (24.7 ± 3.4 years; 90.1 ± 11.3 kg; 176.0 ± 4.9 cm) ingested supplement (SUPP) or placebo (PL) immediately post-exercise in a randomized, cross-over design. Blood samples were obtained at baseline (BL), immediately (IP), 30-min (30P), 1-h (1H), 2-h (2H), and 5-h (5H) post-exercise to assess plasma concentrations of myoglobin; tumor necrosis factor-alpha (TNFα); and expression of tumor necrosis factor receptor 1 (TNFr1) on classical, intermediate, and non-classical monocytes. Magnitude-based inferences were used to provide inferences on the true effects of SUPP compared to PL. Plasma TNFα concentrations were "likely attenuated" (91.6% likelihood effect) from BL to 30P in the SUPP group compared with PL (d = 0.87; mean effect: 2.3 ± 2.4 pg mL-1). TNFr1 expressions on classical (75.9% likelihood effect) and intermediate (93.0% likelihood effect) monocytes were "likely attenuated" from BL to 2H in the SUPP group compared with PL (d = 0.67; mean effect: 510 ± 670 RFU, and d = 1.05; mean effect: 2500 ± 2300 RFU, respectively). TNFr1 expression on non-classical monocytes was "likely attenuated" (77.6% likelihood effect) from BL to 1H in the SUPP group compared with PL (d = 0.69; mean effect: 330 ± 430 RFU). Ingestion of a milk protein supplement immediately post-exercise appears to attenuate both plasma TNFα concentrations and TNFr1 expression on monocyte subpopulations in resistance-trained men.


Asunto(s)
Suplementos Dietéticos , Proteínas de la Leche/administración & dosificación , Monocitos/metabolismo , Receptores Tipo I de Factores de Necrosis Tumoral/sangre , Entrenamiento de Fuerza , Factor de Necrosis Tumoral alfa/sangre , Adulto , Células Cultivadas , Estudios Cruzados , Ingestión de Alimentos , Humanos , Inflamación/metabolismo , Inflamación/prevención & control , Masculino , Monocitos/citología , Adulto Joven
11.
J Appl Physiol (1985) ; 123(1): 11-18, 2017 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-28408697

RESUMEN

The purpose of this study was to compare the coadministration of the probiotic Bacillus coagulans GBI-30, 6086 (BC30) with ß-hydroxy-ß-methylbutyrate (HMB) calcium (CaHMB) to CaHMB alone on inflammatory response and muscle integrity during 40 days of intense military training. Soldiers were randomly assigned to one of two groups: CaHMB with BC30 (CaHMBBC30; n = 9) or CaHMB with placebo (CaHMBPL, n = 9). A third group of participants served as a control (CTL; n = 8). During the first 28 days soldiers were garrisoned on base and participated in the same training tasks. During the final 2 wk soldiers navigated 25-30 km per night in difficult terrain carrying ~35 kg of equipment. All assessments (blood draws and diffusion tensor imaging to assess muscle integrity) were conducted before and ~12 h after final supplement consumption. Analysis of covariance was used to analyze all blood and muscle measures. Significant attenuations were noted in IL-1ß, IL-2, IL-6, CX3CL1, and TNF-α for both CaHMBBC30 and CaHMBPL compared with CTL. Plasma IL-10 concentrations were significantly attenuated for CaHMBBC30 compared with CTL only. A significant decrease in apparent diffusion coefficients was also observed for CaHMBBC30 compared with CaHMBPL. Results provide further evidence that HMB supplementation may attenuate the inflammatory response to intense training and that the combination of the probiotic BC30 with CaHMB may be more beneficial than CaHMB alone in maintaining muscle integrity during intense military training.NEW & NOTEWORTHY ß-Hydroxy-ß-methylbutyrate (HMB) in its free acid form was reported to attenuate inflammation and maintain muscle integrity during military training. However, this formulation was difficult to maintain in the field. In this investigation, soldiers ingested HMB calcium (CaHMB) with Bacillus coagulans (BC30) or CaHMB alone during 40 days of training. Results indicated that CaHMB attenuated the inflammatory response and that BC30 combined with CaHMB may be more beneficial than CaHMB alone in maintaining muscle integrity during intense military training.


Asunto(s)
Bacillus coagulans , Citocinas/sangre , Suplementos Dietéticos , Ejercicio Físico/fisiología , Personal Militar , Músculo Esquelético/metabolismo , Valeratos/administración & dosificación , Imagen de Difusión Tensora/métodos , Método Doble Ciego , Quimioterapia Combinada , Humanos , Masculino , Músculo Esquelético/diagnóstico por imagen , Músculo Esquelético/efectos de los fármacos , Probióticos/administración & dosificación , Adulto Joven
12.
Nutrients ; 8(7)2016 Jul 02.
Artículo en Inglés | MEDLINE | ID: mdl-27384580

RESUMEN

The recruitment and infiltration of classical monocytes into damaged muscle is critical for optimal tissue remodeling. This study examined the effects of an amino acid supplement on classical monocyte recruitment following an acute bout of lower body resistance exercise. Ten resistance-trained men (24.7 ± 3.4 years; 90.1 ± 11.3 kg; 176.0 ± 4.9 cm) ingested supplement (SUPP) or placebo (PL) immediately post-exercise in a randomized, cross-over design. Blood samples were obtained at baseline (BL), immediately (IP), 30-min (30P), 1-h (1H), 2-h (2H), and 5-h (5H) post-exercise to assess plasma concentrations of monocyte chemoattractant protein 1 (MCP-1), myoglobin, cortisol and insulin concentrations; and expressions of C-C chemokine receptor-2 (CCR2), and macrophage-1 antigen (CD11b) on classical monocytes. Magnitude-based inferences were used to provide inferences on the true effects of SUPP compared to PL. Changes in myoglobin, cortisol, and insulin concentrations were similar between treatments. Compared to PL, plasma MCP-1 was "very likely greater" (98.1% likelihood effect) in SUPP at 2H. CCR2 expression was "likely greater" at IP (84.9% likelihood effect), "likely greater" at 1H (87.7% likelihood effect), "very likely greater" at 2H (97.0% likelihood effect), and "likely greater" at 5H (90.1% likelihood effect) in SUPP, compared to PL. Ingestion of SUPP did not influence CD11b expression. Ingestion of an amino acid supplement immediately post-exercise appears to help maintain plasma MCP-1 concentrations and augment CCR2 expression in resistance trained men.


Asunto(s)
Aminoácidos/administración & dosificación , Quimiocina CCL2/sangre , Suplementos Dietéticos , Receptores CCR2/metabolismo , Entrenamiento de Fuerza , Administración Oral , Adulto , Biomarcadores/sangre , Índice de Masa Corporal , Peso Corporal , Antígeno CD11b/genética , Antígeno CD11b/metabolismo , Estudios Cruzados , Dieta , Humanos , Hidrocortisona/sangre , Insulina/sangre , Ácido Láctico/sangre , Masculino , Monocitos/efectos de los fármacos , Mioglobina/sangre , Receptores CCR2/genética , Adulto Joven
13.
J Int Soc Sports Nutr ; 12: 37, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26445565

RESUMEN

BACKGROUND: The purpose of this study was to examine the ergogenic benefits of Turkish coffee consumed an hour before exercise. In addition, metabolic, cardiovascular, and subjective measures of energy, focus and alertness were examined in healthy, recreationally active adults who were regular caffeine consumers (>200 mg per day). METHODS: Twenty males (n = 10) and females (n = 10), age 24.1 ± 2.9 y; height 1.70 ± 0.09 m; body mass 73.0 ± 13.0 kg (mean ± SD), ingested both Turkish coffee [3 mg · kg(-1) BW of caffeine, (TC)], and decaffeinated Turkish coffee (DC) in a double-blind, randomized, cross-over design. Performance measures included a 5 km time trial, upper and lower body reaction to visual stimuli, and multiple object tracking. Plasma caffeine concentrations, blood pressure (BP), heart rate and subjective measures of energy, focus and alertness were assessed at baseline (BL), 30-min following coffee ingestion (30+), prior to endurance exercise (PRE) and immediately-post 5 km (IP). Metabolic measures [VO2, V E , and respiratory exchange rate (RER)] were measured during the 5 km. RESULTS: Plasma caffeine concentrations were significantly greater during TC (p < 0.001) at 30+, PRE, and IP compared to DC. Significantly higher energy levels were reported at 30+ and PRE for TC compared to DC. Upper body reaction performance (p = 0.023) and RER (p = 0.019) were significantly higher for TC (85.1 ± 11.6 "hits," and 0.98 ± 0.05 respectively) compared to DC (81.2 ± 13.7 "hits," and 0.96 ± 0.05, respectively). Although no significant differences (p = 0.192) were observed in 5 km run time, 12 of the 20 subjects ran faster (p = 0.012) during TC (1662 ± 252 s) compared to DC (1743 ± 296 s). Systolic BP was significantly elevated during TC in comparison to DC. No other differences (p > 0.05) were noted in any of the other performance or metabolic measures. CONCLUSIONS: Acute ingestion of TC resulted in a significant elevation in plasma caffeine concentrations within 30-min of consumption. TC ingestion resulted in significant performance benefits in reaction time and an increase in subjective feelings of energy in habitual caffeine users. No significant differences were noted in time for the 5 km between trials, however 60 % of the participants performed the 5 km faster during the TC trial and were deemed responders. When comparing TC to DC in responders only, significantly faster times were noted when consuming TC compared to DC. No significant benefits were noted in measures of cognitive function.


Asunto(s)
Rendimiento Atlético , Café , Tiempo de Reacción/efectos de los fármacos , Adulto , Glucemia/metabolismo , Presión Sanguínea/efectos de los fármacos , Índice de Masa Corporal , Cafeína/administración & dosificación , Cafeína/sangre , Cognición/efectos de los fármacos , Estudios Cruzados , Método Doble Ciego , Ejercicio Físico , Femenino , Frecuencia Cardíaca/efectos de los fármacos , Humanos , Ácido Láctico/sangre , Masculino , Sustancias para Mejorar el Rendimiento/administración & dosificación , Sustancias para Mejorar el Rendimiento/sangre , Adulto Joven
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