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1.
J Strength Cond Res ; 37(7): e413-e421, 2023 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-36727984

RESUMEN

ABSTRACT: Waldman, HS, Bryant, AR, Parten, AL, Grozier, CD, and McAllister, MJ. Astaxanthin supplementation does not affect markers of muscle damage or inflammation after an exercise-induced muscle damage protocol in resistance-trained males. J Strength Cond Res 37(7): e413-e421, 2023-It is well documented that exercise-induced muscle damage (EIMD) decreases exercise performance by elevated inflammation and subjective discomfort. Due to its potent antioxidative properties, astaxanthin (AX) may serve as a potential dietary supplement strategy for mitigating delayed-onset muscle soreness (DOMS) and enhancing recovery and performance. This study aimed to investigate the effects of AX on markers of muscle damage, inflammation, DOMS, and anaerobic performance and substrate metabolism. Thirteen resistance-trained men (mean ± SD , age, 23.4 ± 2.1 years) completed a double-blind, counterbalanced, and crossover design with a 1-week washout period between 2, 4-week supplementation periods at 12 mg·d -1 of AX or placebo. After each supplementation period, subjects completed 2 trials, with trial 1 including a graded exercise test (GXT) and a 30-second Wingate and trial 2 including an EIMD protocol followed by the collection of fasting blood samples (pre-post) to measure creatine kinase, advanced oxidative protein products, C-reactive protein, interleukin-6, insulin, and cortisol. Astaxanthin supplementation had no statistical effects on markers of substrate metabolism during the GXT, Wingate variables, or markers of muscle damage, inflammation, or DOMS when compared with placebo (all p > 0.05). However, 4 weeks of AX supplementation did significantly lower oxygen consumption during the final stage of the GXT (12%, p = 0.02), as well as lowered systolic blood pressure (∼7%, p = 0.04), and significantly lowered baseline insulin values (∼24%, p = 0.05) when compared with placebo. Collectively, these data suggest that 4 weeks of AX supplementation at 12 mg·d -1 did not affect markers of muscle damage, inflammation, or DOMS after an EIMD protocol in a resistance-trained male cohort.


Asunto(s)
Insulinas , Mialgia , Humanos , Masculino , Lactante , Suplementos Dietéticos , Inflamación , Insulinas/farmacología , Músculos , Músculo Esquelético/fisiología , Método Doble Ciego , Ensayos Clínicos Controlados Aleatorios como Asunto
2.
J Diet Suppl ; 20(1): 89-105, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-34477469

RESUMEN

Betaine (BET) has shown to be effective in improving body composition and performance, although research in women is lacking. This study investigated the effects of BET supplementation on markers of metabolic flexibility, body composition, and anaerobic performance in college females. Twenty-three active subjects with 21.8 ± 3.0 years of age, 66.6 ± 8.8 kg body mass, 1.6 ± 0.1 m height, and 23.2 ± 5.3% body fat performed a graded exercise test on a cycle ergometer consisting of 4 incremental, 3 min stages for collection of fat and carbohydrate oxidation rates. Three 10 s sprint tests were then completed against a resistance of 7.5% of body mass, separated by 2.5 min of recovery. The study comprised 3 phases: (a) pre-supplementation, (b) randomization to supplement for 2-weeks with either 2.4 g/day BET or placebo (parallel design), and (c) post-supplementation. Repeated-measures analysis of variance were conducted to determine interactions or main effects. There were no group differences for substrate oxidation rates (p > 0.05). Although body composition improved pre-post for both groups (p < 0.05), only the BET group experienced a significant increase in fat free mass (p < 0.01; ∼3%). Further, only the BET group experienced improvements to performance such as a higher mean power output during the final sprint (p = 0.02; ∼3%) and a lower RPE during the final stage of the graded exercise test (p = 0.02). Results from this study suggest BET supplementation may improve body composition and some markers of performance during exercise in collegiate women.


Asunto(s)
Betaína , Suplementos Dietéticos , Femenino , Humanos , Anaerobiosis , Composición Corporal , Ejercicio Físico , Adulto Joven
3.
J Strength Cond Res ; 36(3): 763-771, 2022 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-35180190

RESUMEN

ABSTRACT: Waldman, HS, Bryant, AR, Shepherd, BD, Egan, B, and McAllister, MJ. No effect of a ketone monoester on markers of stress and performance in a live-burn search and rescue in firefighters. J Strength Cond Res 36(3): 763-771, 2022-Firefighters experience a range of stressors that impair performance and elevate the risk for developing cardiometabolic diseases. ß-Hydroxybutyrate (ßHB) has been shown to mitigate markers of oxidative stress and inflammation and serve as an alternative fuel with implications to physical performance. On 2 occasions in a double-blind, counterbalanced, and crossover design, 14 professional firefighters performed a live-burn, search and rescue (S&R) 30 minutes after ingestion of a ketone monoester (KME; 0.5 g·kg-1) or a placebo (PLA). Dependent variables collected before and after the S&R included salivary markers of stress and inflammation (cortisol, α-amylase, interleukin-1 beta, uric acid), perceptual markers (profile of mood state [POMS]), gastrointestinal distress (GI), rating of perceived exertion [RPE]), time to completion, and capillary blood measurement of ßHB and glucose. KME resulted in capillary ßHB concentrations of approximately 2.1-3.2 mM throughout the protocol. Capillary glucose concentrations were lower for the KME compared with PLA (∼7%) (interaction effect, p < 0.001). Salivary markers of stress, GI, and time to complete the S&R (∼10 minutes) did not differ between trials, although KME ingestion resulted in significantly higher RPE after the live-burn S&R (KME,6 ± 1; PLA, 4 ± 1). However, POMS data showed the KME also lowered subjective states of nervousness (KME, 0.0 ± 0.0; PLA, 0.6 ± 0.8) and anxiety (KME, 0.0 ± 0.0; PLA, 0.6 ± 0.7) before the S&R (all p < 0.05; large effect sizes). Compared with PLA, ingestion of a KME by firefighters did not mitigate the rise in various markers of salivary stress or impact physical performance during a live-burn S&R. However, differences in RPE and POMS variables were observed, suggesting a possible cognitive role for ßHB.


Asunto(s)
Quemaduras , Bomberos , Glucemia , Suplementos Dietéticos , Humanos , Cetonas/farmacología , Trabajo de Rescate
4.
Int J Sport Nutr Exerc Metab ; 32(1): 8-15, 2022 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-34611051

RESUMEN

This study investigated the effects of 6 mg/day of astaxanthin supplementation on markers of oxidative stress and substrate metabolism during a graded exercise test in active young men. A double-blind, randomized, counterbalanced, cross-over design was used. Fourteen men (age = 23 ± 2 years) supplemented with 6 mg/day of astaxanthin and a placebo for 4 weeks, with a 1 week washout period between treatments. Following each supplementation period, a fasting blood sample was obtained to measure markers of oxidative stress: glutathione, hydrogen peroxide, advanced oxidation protein products, and malondialdehyde. Participants also completed a graded exercise test after each treatment to determine substrate utilization during exercise at increasing levels of intensity. Glutathione was ∼7% higher following astaxanthin compared with placebo (1,233 ± 133 vs. 1,156 ± 185 µM, respectively; p = .02, d = 0.48). Plasma hydrogen peroxide and malondialdehyde were not different between treatments (p > .05). Although not statistically significant (p = .45), advanced oxidation protein products were reduced by ∼28%. During the graded exercise test, mean fat oxidation rates were not different between treatments (p > .05); however, fat oxidation decreased from 50 to 120 W (p < .001) and from 85 to 120 W (p = .004) in both conditions. Astaxanthin supplementation of 6 mg/day for 4 weeks increased whole blood levels of the antioxidant glutathione in active young men but did not affect oxidative stress markers or substrate utilization during exercise. Astaxanthin appears to be an effective agent to increase endogenous antioxidant status.


Asunto(s)
Glutatión , Xantófilas , Adulto , Antioxidantes/metabolismo , Suplementos Dietéticos , Método Doble Ciego , Glutatión/metabolismo , Humanos , Masculino , Oxidación-Reducción , Estrés Oxidativo , Adulto Joven
5.
Can J Physiol Pharmacol ; 98(4): 194-200, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-31689118

RESUMEN

Ingestion of ketone supplements, caffeine, and medium-chain triglycerides (MCTs) may all be effective strategies to increase blood levels of the ketone body beta-hydroxybutyrate (D-BHB). However, acute ingestion of a bolus of lipids may increase oxidative stress (OS). The purpose of the study was to investigate the impact of adding varying amounts of MCTs to coffee on blood levels of D-BHB and markers of OS. Ten college-aged men ingested coffee with 0, 28, and 42 g of MCT in a randomized order. Blood samples were collected pre- as well as 2 and 4 h postprandial and analyzed for D-BHB, total cholesterol (TC), high-density lipoprotein cholesterol (HDL-c), glucose, triglycerides (TAG), insulin, and OS markers: advanced oxidation protein products (AOPP), glutathione (GSH), malondialdehyde (MDA), and hydrogen peroxide (H2O2). All three treatments resulted in a significant increase in D-BHB, HDL-c, and TC as well as a significant decrease in TAG, MDA, H2O2, and insulin. The 42 g treatment was associated with significantly higher levels of AOPP and MDA. Acute ingestion of coffee results in favorable changes to markers of cardiometabolic health that were not impacted by the addition of 28 g of MCT. However, 42 g of MCT caused significantly greater OS.


Asunto(s)
Biomarcadores/sangre , Café/metabolismo , Ingestión de Alimentos/fisiología , Cetonas/sangre , Estrés Oxidativo/fisiología , Triglicéridos/sangre , Adulto , Biomarcadores/metabolismo , Glucemia/metabolismo , HDL-Colesterol/sangre , Suplementos Dietéticos , Método Doble Ciego , Glucosa/metabolismo , Humanos , Peróxido de Hidrógeno/metabolismo , Insulina/sangre , Masculino , Malondialdehído/metabolismo , Periodo Posprandial/fisiología , Adulto Joven
6.
J Occup Environ Med ; 60(11): e595-e601, 2018 11.
Artículo en Inglés | MEDLINE | ID: mdl-30252723

RESUMEN

OBJECTIVE: Firefighters (FFs) involved in fire suppression have the greatest on-duty risk of cardiovascular disease (CVD), which may be caused by oxidative stress (OS). METHODS: Healthy, active FFs performed a victim "search and clear" exercise involving three conditions: (1) no heat, (2) heat + antioxidant, and (3) heat + placebo. Blood samples were analyzed for OS markers glutathione (GSH), oxidized glutathione (GSSG), superoxide dismutase (SOD), catalase (CAT), and advanced oxidation protein products (AOPP). RESULTS: Increased GSH was found during both heat conditions compared with no heat. CAT activity was higher immediately post exercise. AOPP was reduced post exercise. CONCLUSIONS: Antioxidant supplementation did not impact the OS response to exercise. Added heat did not cause OS and exercise resulted in reductions in OS markers. These findings can be attributed to the training status of the FFs involved.


Asunto(s)
Antioxidantes/administración & dosificación , Curcumina/administración & dosificación , Bomberos , Calor , Estrés Oxidativo , Esfuerzo Físico/fisiología , Adulto , Productos Avanzados de Oxidación de Proteínas/sangre , Biomarcadores/sangre , Catalasa/sangre , Estudios Cruzados , Método Doble Ciego , Incendios , Disulfuro de Glutatión/sangre , Frecuencia Cardíaca , Humanos , Masculino , Superóxido Dismutasa/sangre
7.
Appl Physiol Nutr Metab ; 43(5): 504-509, 2018 May.
Artículo en Inglés | MEDLINE | ID: mdl-29244956

RESUMEN

The purpose of this investigation was to examine the individual and combined effects of ingesting carbohydrates (CHO) and branched-chain amino acids (BCAA) during high-volume upper body resistance exercise (RE) on markers of catabolism and performance. Thirteen resistance-trained males completed 4 experimental trials with supplementation, ingesting beverages containing CHO, BCAA, CHO+BCAA, or placebo (PLA) in a randomized, double-blind design. The beverages were ingested in 118-mL servings 6 times during an ∼60-min RE session consisting of bench press, bent-over row, incline press, and close-grip row. Each RE was performed with 5 sets of repetitions at 65% 1-repetition maximum until volitional fatigue. Blood samples were collected at baseline, immediately postexercise, and 60 min postexercise to assess glucose and insulin. Cortisol was assessed immediately and at 60 min postexercise. No significant performance benefits were observed for any RE. CHO+BCAA (152.4 ± 71.4 ng/mL) resulted in the lowest cortisol levels, which was lower than BCAA and PLA (193.7 ± 88.5, 182.8 ± 67.5 ng/mL, p < 0.05), but not different from CHO (165 ± 76.5 ng/mL, p = 0.342). Postexercise insulin concentrations were significantly higher with CHO (4.79 ± 3.4 mU/L) compared with BCAA and PLA (3.7 ± 2.0, 3.5 ± 1.8 mU/L, p < 0.05), but not different from CHO+BCAA (4.3 ± 2.5 mU/L, p = 0.339). There was no treatment effect for glucose, but glucose significantly increased from baseline to immediately postexercise and significantly decreased at 60 min postexercise. Ingesting beverages containing CHO with or without BCAA during upper body resistance exercise may promote a more favorable postexercise less catabolic environment.


Asunto(s)
Aminoácidos de Cadena Ramificada/administración & dosificación , Carbohidratos de la Dieta/administración & dosificación , Hidrocortisona/sangre , Insulina/sangre , Entrenamiento de Fuerza , Adulto , Bebidas , Glucemia/metabolismo , Estudios Cruzados , Dieta , Grasas de la Dieta/administración & dosificación , Proteínas en la Dieta/administración & dosificación , Suplementos Dietéticos , Método Doble Ciego , Humanos , Masculino , Músculo Esquelético/fisiología , Resistencia Física , Adulto Joven
8.
Sports Med Open ; 1(1): 32, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26435910

RESUMEN

Obesity-related oxidative stress, the imbalance between pro-oxidants and antioxidants (e.g., nitric oxide), has been linked to metabolic and cardiovascular disease, including endothelial dysfunction and atherosclerosis. Reactive oxygen species (ROS) are essential for physiological functions including gene expression, cellular growth, infection defense, and modulating endothelial function. However, elevated ROS and/or diminished antioxidant capacity leading to oxidative stress can lead to dysfunction. Physical activity also results in an acute state of oxidative stress. However, it is likely that chronic physical activity provides a stimulus for favorable oxidative adaptations and enhanced physiological performance and physical health, although distinct responses between aerobic and anaerobic activities warrant further investigation. Studies support the benefits of dietary modification as well as exercise interventions in alleviating oxidative stress susceptibility. Since obese individuals tend to demonstrate elevated markers of oxidative stress, the implications for this population are significant. Therefore, in this review our aim is to discuss (i) the role of oxidative stress and inflammation as associated with obesity-related diseases, (ii) the potential concerns and benefits of exercise-mediated oxidative stress, and (iii) the advantageous role of dietary modification, including acute or chronic caloric restriction and vitamin D supplementation.

9.
Inflamm Res ; 64(8): 565-75, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-26142253

RESUMEN

Vitamin D plays an essential role in the regulation of skeletal metabolism as well as calcium and phosphate homeostasis, while vitamin D receptor (VDR) regulates de novo lipid synthesis, thereby contributing to the development of obesity. Furthermore, obese individuals are at a greater risk for vitamin D deficiency which may increase the potential risk for chronic inflammation, insulin resistance, and metabolic syndrome. While acute exercise enhances the activation of inflammatory signaling pathways, chronic exercise training may attenuate elevated pro-inflammatory cytokine production, resulting in the improvement of cardiovascular and metabolic health in obese individuals. Supplementation with vitamin D coupled with exercise or mild caloric restriction has been shown to improve markers of fitness and inflammation as well as cholesterol. Therefore, this review primarily addresses the impact of vitamin D deficiency in obesity-related inflammatory imbalances and how exercise and weight-loss interventions may enhance the beneficial effects on vitamin D-mediated inflammation in obesity.


Asunto(s)
Obesidad/metabolismo , Vitamina D/metabolismo , Animales , Suplementos Dietéticos , Terapia por Ejercicio , Humanos , Inflamación/metabolismo , Obesidad/dietoterapia , Obesidad/tratamiento farmacológico , Vitamina D/farmacología , Vitamina D/uso terapéutico , Pérdida de Peso/efectos de los fármacos
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