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1.
Nutrients ; 15(24)2023 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-38140311

RESUMO

The completion of high-intensity exercise results in robust perturbations to physiologic homeostasis, challenging the body's natural buffering systems to mitigate the accumulation of metabolic by-products. Supplementation with bicarbonate has previously been used to offset metabolic acidosis, leading to improvements in anaerobic exercise performance. PURPOSE: The purpose of this study was to investigate the presence of ergogenic properties in naturally occurring low-dose bicarbonated water and their effects on anaerobic cycling performance and blood gas kinetics in recreationally active men and women. METHODS: Thirty-nine healthy, recreationally active men and women (28.1 ± 8.0 years, 169.8 ± 11.7 cm, 68.9 ± 10.8 kg, 20.1 ± 7.9% fat, V˙O2peak: 42.8 ± 7.6 mL/kg/min) completed two separate testing sessions consisting of 15 cycling sprints (10 s sprint, 20 s active rest) against 7.5% of their body mass. Using a randomized, double-blind, placebo-controlled, parallel group study design, study participants consumed a 10 mL/kg dose of either spring water (SW) or bicarbonated mineral water (BMW) (delivering ~3 g/day of bicarbonate) for 7 days. Venous blood was collected before, immediately after, and 5 and 10 min after the sprint protocol and was analyzed for lactate and a series of blood gas components. After the completion of 15 cycling sprints, averages of peak and mean power for bouts 1-5, 6-10, and 11-15, along with total work for the entire cycling protocol, were calculated. All performance and blood gas parameters were analyzed using a mixed-factorial ANOVA. RESULTS: pH was found to be significantly higher in the BMW group immediately after (7.17 ± 0.09 vs. 7.20 ± 0.11; p = 0.05) and 10 min post exercise (7.21 ± 0.11 vs. 7.24 ± 0.09; p = 0.04). A similar pattern of change was observed 5 min post exercise wherein pH levels in the SW group were lower than those observed in the BMW group; however, this difference did not achieve statistical significance (p = 0.09). A statistical trend (p = 0.06) was observed wherein lactate in the BMW group tended to be lower than in the SW group 5 min post exercise. No significant main effect for time (p > 0.05) or group × time interactions (p > 0.05) for the total work, average values of peak power, or average values of mean power were observed, indicating performance was unchanged. CONCLUSION: One week of consuming water with increased bicarbonate (10 mL/kg; ~3 g/day bicarbonate) showed no effect on anaerobic cycling performance. BMW decreased blood lactate concentrations 5 min after exercise and increased blood pH immediately and 10 min after exercise.


Assuntos
Desempenho Atlético , Águas Minerais , Masculino , Humanos , Feminino , Bicarbonatos , Anaerobiose , Ácido Láctico , Ciclismo/fisiologia , Suplementos Nutricionais , Método Duplo-Cego
2.
J Diet Suppl ; 20(6): 832-849, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36184601

RESUMO

L-Beta-amino isobutyric acid (L-BAIBA) is a myokine produced in skeletal muscle during exercise and has been shown to impact carbohydrate and fat metabolism in both animals and humans. This study was designed to determine the rate and extent to which L-BAIBA appeared in human plasma after oral ingestion. In a randomized, double-blind, placebo-controlled, crossover fashion, six males and 6 females (N = 12; 24 ± 5 yrs; 173.6 ± 12.0 cm; 72.3 ± 11.3 kg; 21.0 ± 7.0 body fat %) completed a single-dose supplementation protocol of placebo (PLA), L-BAIBA at 250 mg (B250), 500 mg (B500), 1,500mg (B1500), and 1,500mg of valine (V1500). Participants fasted overnight (8-10 h) and consumed their dose with 8-12 fluid ounces of cold water. Venous blood samples were collected 0, 30, 60, 90, 120, 180, 240 and 300 min after ingestion and analyzed for L-BAIBA. Complete blood counts and comprehensive metabolic panels were analyzed 0 and 300 min after ingestion. Peak concentration (CMax) and area under the curve (AUC) were calculated for all variables. Baseline L-BAIBA levels were not different between conditions (p = 0.46). The observed AUC for B1500 (30,513 ± 9190 µM•300 min) was significantly higher than B500 (11,087 ± 3378 µM•300 min, p < 0.001), B250 (7081 ± 2535 µM•300 min, p < 0.001), V1500 (2837 ± 2107 µM•300 min, p < 0.001), and PLA (2836 ± 2061 µM•300 min, p < 0.001). Similarly, L-BAIBA CMax for B1500 (278.1 ± 52.1 µM) was significantly higher than all other supplement conditions: B500 (95.4 ± 33.5 µM, p < 0.001), B250 (63.3 ± 61.1 µM, p < 0.001), V1500 (10.1 ± 7.2 µM, p < 0.001), PLA (11.0 ± 7.1 µM, p = 0.001). AUC and CMax for B500 was significantly higher than B250 (p < 0.001), V1500 (p < 0.001), and PLA (p < 0.001). BAIBA AUC for B250 was significantly higher than V1500 (p < 0.001) and PLA (p < 0.001). No clinically significant changes in blood-based markers of health or adverse events were observed across the study protocol. L-BAIBA doses of 250 mg, 500 mg, and 1500 mg produced significantly greater concentrations of plasma L-BAIBA across a five-hour measurement window when compared to a 1500 mg dose of valine or a placebo. Follow-up efficacy studies on resting and exercise metabolism should be completed to assess the impact of L-BAIBA supplementation in normal weight and overweight individuals. Retrospectively registered on April 22, 2022 at ClinicalTrials.gov as NCT05328271.


Assuntos
Ácidos Aminoisobutíricos , Suplementos Nutricionais , Feminino , Humanos , Masculino , Poliésteres , Valina , Adulto Jovem , Adulto
3.
Nutrients ; 14(1)2021 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-35010998

RESUMO

Berberine is a natural alkaloid used to improve glycemia but displays poor bioavailability and increased rates of gastrointestinal distress at higher doses. Recently, dihydroberberine has been developed to combat these challenges. This study was designed to determine the rate and extent to which berberine appeared in human plasma after oral ingestion of a 500 mg dose of berberine (B500) or 100 mg and 200 mg doses of dihydroberberine (D100 and D200). In a randomized, double-blind, crossover fashion, five males (26 ± 2.6 years; 184.2 ± 11.6 cm; 91.8 ± 10.1 kg; 17.1 ± 3.5% fat) completed a four-dose supplementation protocol of placebo (PLA), B500, D100, and D200. The day prior to their scheduled visit, participants ingested three separate doses with breakfast, lunch, and dinner. Participants fasted overnight (8-10 h) and consumed their fourth dose with a standardized test meal (30 g glucose solution, 3 slices white bread) after arrival. Venous blood samples were collected 0, 20, 40, 60, 90, and 120 minutes (min) after ingestion and analyzed for BBR, glucose, and insulin. Peak concentration (CMax) and area under the curve (AUC) were calculated for all variables. Baseline berberine levels were different between groups (p = 0.006), with pairwise comparisons indicating that baseline levels of PLA and B500 were different than D100. Berberine CMax tended to be different (p = 0.06) between all conditions. Specifically, the observed CMax for D100 (3.76 ± 1.4 ng/mL) was different than PLA (0.22 ± 0.18 ng/mL, p = 0.005) and B500 (0.4 ± 0.17 ng/mL, p = 0.005). CMax for D200 (12.0 ± 10.1 ng/mL) tended (p = 0.06) to be different than B500. No difference in CMax was found between D100 and D200 (p = 0.11). Significant differences in berberine AUC were found between D100 (284.4 ± 115.9 ng/mL × 120 min) and PLA (20.2 ± 16.2 ng/mL × 120 min, p = 0.007) and between D100 and B500 (42.3 ± 17.6 ng/mL × 120 min, p = 0.04). Significant differences in D100 BBR AUC (284.4 ± 115.9 ng/mL×120 min) were found between PLA (20.2 ± 16.2 ng/mL × 120 min, p = 0.042) and B500 (42.3 ± 17.6 ng/mL × 120 min, p = 0.045). Berberine AUC values between D100 and D200 tended (p = 0.073) to be different. No significant differences in the levels of glucose (p = 0.97) and insulin (p = 0.24) were observed across the study protocol. These results provide preliminary evidence that four doses of a 100 mg dose of dihydroberberine and 200 mg dose of dihydroberberine produce significantly greater concentrations of plasma berberine across of two-hour measurement window when compared to a 500 mg dose of berberine or a placebo. The lack of observed changes in glucose and insulin were likely due to the short duration of supplementation and insulin responsive nature of study participants. Follow-up efficacy studies on glucose and insulin changes should be completed to assess the impact of berberine and dihydroberberine supplementation in overweight, glucose intolerant populations.


Assuntos
Berberina/análogos & derivados , Berberina/farmacocinética , Glicemia/efeitos dos fármacos , Absorção Gastrointestinal/efeitos dos fármacos , Período Pós-Prandial/efeitos dos fármacos , Adolescente , Adulto , Área Sob a Curva , Berberina/sangue , Disponibilidade Biológica , Estudos Cross-Over , Suplementos Nutricionais , Método Duplo-Cego , Voluntários Saudáveis , Humanos , Insulina/sangue , Cinética , Masculino , Refeições , Pessoa de Meia-Idade , Projetos Piloto , Adulto Jovem
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