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1.
Nutrients ; 15(11)2023 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-37299583

RESUMO

(1) Background: Iron deficiency without anemia (IDWA) is a prevalent health concern in premenopausal women. Oral supplementation of iron may be a viable solution to improve blood-iron status in women; however, the effects of a high-dose iron-supplement regimen have been associated with gastrointestinal side effects. Therefore, the purpose of the present study was to evaluate the effectiveness of a low-dose liquid fermented iron-bisglycinate supplement (LIS) on improving blood-iron status in premenopausal women with IDWA without increasing constipation or gastrointestinal distress. (2) Methods: 85 premenopausal women with IDWA (ferritin < 70 ng/dL and hemoglobin > 11.0 g/dL) took a LIS (27 mg) or a placebo (PLA) for 8 weeks. Blood draws were taken at Wk0 and Wk8 of the study to measure serum-iron markers. In addition, surveys of gastrointestinal distress were administered at Wk0, Wk4, and Wk8 while the profile of mood states (POMS) was surveyed at Wk0 and Wk8. (3) Results: Compared to the placebo, the LIS was able to increase serum ferritin (p = 0.03), total serum iron (p = 0.03), and mean corpuscular volume (p = 0.02), while exhibiting no significant interaction in subjective gastrointestinal distress (p > 0.05). No significant effects were detected for POMS (p > 0.05). (4) Conclusions: Supplementing with LIS appears to improve blood-iron status without causing significant gastrointestinal distress in premenopausal women with IDWA.


Assuntos
Anemia Ferropriva , Anemia , Dispepsia , Gastroenteropatias , Deficiências de Ferro , Humanos , Feminino , Valores de Referência , Ferro , Ferritinas , Hemoglobinas/análise , Anemia Ferropriva/tratamento farmacológico
2.
Int J Sports Physiol Perform ; 18(5): 523-529, 2023 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-36944365

RESUMO

PURPOSE: The purpose of this study was to explore whether offset loading in the barbell squat altered ground-reaction force (GRF) and muscle activation in the dominant (D) and nondominant (ND) lower limb compared to traditional squats. METHODS: Twelve well-trained men (age 26.4 [3.2] y; 10.3 [1.9] y experience) performed 3 sets of 10 repetitions at 60% of their previously measured 1-repetition maximum. Sets were quasi-randomized between traditional loading (TDL), dominant-side offset loading (OS-D), and nondominant-side offset loading (OS-ND). All repetitions were performed on a dual force plate with electromyography sensors on the prime mover muscles of the squat. GRF symmetry was assessed using the symmetry index (SI) to determine the direction (D [+] or ND [-]) and magnitude (%) of the asymmetry. Finally, the first 3 and final 3 repetitions of each set were compared for compensatory changes in symmetry. RESULTS: OS-D induced a significant change in limb SI relative to TDL (5.21% vs 1.44%; P = .011); however, no significant difference in limb SI was seen between TDL and OS-ND (-0.66% vs 1.44%; P = .278). No asymmetries between D and ND muscle activation were present in any condition. TDL and OS-D squats exhibited significant improvements in limb SI between the first 3 and final 3 repetitions (P = .035 and .011, respectively); however, no such improvement was seen in OS-ND. CONCLUSIONS: OS-D is capable of significantly altering GRF limb SI in a bilateral squat; however, OS-ND appears to exhibit no GRF or electromyography effects relative to TDL. Thus, the results of this study do not support the use of OS-ND in the pursuit of strengthening a weaker limb, suggesting that unilateral training may be a preferred mode of exercise for this desired outcome.


Assuntos
Extremidade Inferior , Postura , Adulto , Humanos , Masculino , Eletromiografia , Extremidade Inferior/fisiologia , Movimento/fisiologia , Músculo Esquelético/fisiologia , Músculos , Levantamento de Peso/fisiologia
3.
Nutr Health ; : 2601060221142330, 2022 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-36448321

RESUMO

BACKGROUND: Vitamin E (α-tocopherol) is an essential micronutrient for human health and optimal physiological function. Inadequacy may be common due to a lack of bioavailability. The use of dietary lipids alongside other emulsification agents may elicit more robust serum concentrations of α-tocopherol via improved bioavailability. Therefore, the aim of the study was to examine oral bioavailability of two delivery methods of α-tocopherol, (1) a microemulsion gel formula composed of dietary lipids and other emulsification agents and (2) a dry solid tablet over 12 hours. METHODS: Twelve participants (age = 37.3 ± 9.6 years; height = 173.4 ± 11.8 cm; body mass = 71.2 ± 10.0 kg) participated in a double-blind, randomized, crossover trial comparing two delivery methods both dosed at 288 mg of α-tocopherol. Serum α-tocopherol concentrations were assessed from blood donated by participants at pre-consumption, 2-, 4-, 8-, and 12-hour post-consumption. Study conditions were separated by a 7-day washout. RESULTS: The microemulsion gel formula delivery demonstrated significantly greater area under the curve (p < 0.001) and serum concentration maximums (p = 0.003) for serum α-tocopherol compared to the tablet delivery. No significant differences were detected between conditions for the time to reach concentration maximums (p = 0.375). CONCLUSION: We conclude that a mixture of dietary lipids and emulsification agents in the form of a microemulsion gel formula was able to significantly improve bioavailability of serum α-tocopherol compared to a tablet by yielding higher serum α-tocopherol maximum concentrations and area under the curve over a 12-hour study period despite dosage being matched.

5.
Nutrients ; 13(10)2021 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-34684429

RESUMO

L-carnitine tartrate has been shown to improve relatively short-term recovery among athletes. However, there is a lack of research on the longer-term effects in the general population. OBJECTIVE: The primary objectives of this randomized double-blind, placebo-controlled trial were to evaluate the effects of daily L-carnitine tartrate supplementation for 5 weeks on recovery and fatigue. METHOD: In this study, eighty participants, 21- to 65-years-old, were recruited. Participants were split into two groups of forty participants each, a placebo, and a L-carnitine Tartrate group. Seventy-three participants completed a maintenance exercise training program that culminated in a high-volume exercise challenge. RESULTS: Compared to placebo, L-carnitine tartrate supplementation was able to improve perceived recovery and soreness (p = 0.021), and lower serum creatine kinase (p = 0.016). In addition, L-carnitine tartrate supplementation was able to blunt declines in strength and power compared to placebo following an exercise challenge. Two sub-analyses indicated that these results were independent of gender and age. Interestingly, serum superoxide dismutase levels increased significantly among those supplementing with L-carnitine tartrate. CONCLUSIONS: These findings agree with previous observations among healthy adult subjects and demonstrate that L-carnitine tartrate supplementation beyond 35 days is beneficial for improving recovery and reducing fatigue following exercise across gender and age.


Assuntos
Carnitina/administração & dosagem , Suplementos Nutricionais , Exercício Físico , Fadiga/reabilitação , Tartaratos/administração & dosagem , Adulto , Fatores Etários , Biomarcadores/sangue , Biomarcadores/metabolismo , Composição Corporal , Fadiga/metabolismo , Feminino , Humanos , Masculino , Força Muscular , Músculo Esquelético/efeitos dos fármacos , Músculo Esquelético/metabolismo , Fatores Sexuais , Superóxido Dismutase/sangue , Superóxido Dismutase/metabolismo
6.
Physiol Behav ; 238: 113461, 2021 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-34000295

RESUMO

The purpose of this study was to determine the impact of an immersive seminar, which included moderate intensities of physical activity, on learning when compared to traditional lecture format. Twenty-six healthy participants were randomly divided into an immersive seminar or traditional lecture format group and presented material related to positive psychology and human values/beliefs over the course of two days. Physical activity was collected using a bio-harness while salivary cortisol and perceptual measures of well-being were collected over the two days. Performance on an examination related to course material was used to assess learning. Average time spent over 65% of max heart rate, energy expenditure, total bounds, mechanical and physiological load were significantly greater in the immersive seminar group when compared to traditional lecture group. In addition, cortisol levels and perceptual measures of mood, focus, energy, and well-being were significantly greater in the immersive seminar when compared to the traditional lecture format. Participants in the immersive seminar demonstrated significantly greater memory retention of course material 30-days post lecture when compared to the traditional lecture group. These findings support incorporating more physical activity and increasing arousal in order to enhance learning of lecture material.


Assuntos
Avaliação Educacional , Aprendizagem , Nível de Alerta , Exercício Físico , Humanos , Memória
7.
Nutrients ; 13(3)2021 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-33807731

RESUMO

The ketogenic diet is a high-fat, very low-carbohydrate, moderate-protein diet that will induce a state of ketosis, but because of its restrictive nature, it may be difficult to adhere to, especially in adolescents. Supplementing with exogenous beta-hydroxybutyrate salts may induce a state of temporary ketosis without any undesirable side effects, thereby promoting the benefits of ketosis and minimizing adherence requirements to a ketogenic diet. To date, beta-hydroxybutyrate supplementation in healthy adolescents has not been explored. Therefore, the purpose of this study was to examine the safety of exogenous beta-hydroxybutyrate salt supplementation in a healthy adolescent population. In the present study, 22 healthy male and female adolescents consumed 3.75 g of beta-hydroxybutyrate salts or maltodextrin placebo twice daily for 90 days. Comprehensive blood safety analysis, bone densitometry, happiness and emotional intelligence surveys, and blood pressure were assessed at Pre, Day 45, and Day 90. There were no significant differences detected in subjects supplementing with beta-hydroxybutyrate salts, indicating that exogenous beta-hydroxybutyrate salts had no detrimental impact on fasting blood safety metrics, bone density, happiness, emotional intelligence, or blood pressure. We conclude that supplementing with exogenous beta-hydroxybutyrate salts is safe and well-tolerated by healthy adolescents.


Assuntos
Ácido 3-Hidroxibutírico/administração & dosagem , Dieta Cetogênica/métodos , Suplementos Nutricionais , Adolescente , Jejum/sangue , Feminino , Voluntários Saudáveis , Humanos , Cetose/sangue , Masculino , Polissacarídeos/administração & dosagem
8.
Phys Act Nutr ; 25(1): 42-55, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33887828

RESUMO

PURPOSE: This study investigated the effects of marine phytoplankton supplementation (Oceanix®, Tetraselmis chuii) on 1) maximal isometric strength and immune function in healthy humans following a oneweek high-intensity resistance-training program and 2) the proinflammatory cytokine response to exercise in a rat model. METHODS: In the human trial, 22 healthy male and female participants were randomly divided into marine phytoplankton and placebo groups. Following baseline testing, participants underwent a 14-day supplement loading phase before completing five consecutive days of intense resistance training. In the rat model, rats were randomly divided into four groups (n=7 per condition): (i) control, (ii) exercise, (iii) exercise + marine phytoplankton (2.55 mg/kg/day), or (iv) exercise + marine phytoplankton (5.1 mg/kg/day). Rats in the exercising groups performed treadmill exercise 5 days per week for 6 weeks. RESULTS: In the human model, marine phytoplankton prevented significant declines in the isometric peak rate of force development compared to placebo. Additionally, salivary immunoglobulin A concentration was significantly lower following the resistance training protocol in the placebo group but not in the marine phytoplankton group. Marine phytoplankton in exercising rats decreased intramuscular levels and serum concentrations of tumor necrosis factor-alpha (TNF-α) and interleukin-1 beta (IL-1ß) and intramuscular concentrations of malondialdehyde. CONCLUSION: Marine phytoplankton prevented decrements in indices of functional exercise recovery and immune function. Mechanistically, these outcomes could be prompted by modulating the oxidative stress and proinflammatory cytokine response to exercise.

9.
Int J Sports Med ; 42(12): 1070-1082, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33352600

RESUMO

This study investigated the effects of marine phytoplankton supplementation on 1) perceived recovery and ground reaction forces in humans following a non-functional overreaching resistance-training program and 2) myogenic molecular markers associated with muscle cell recovery in a rat model. In the human trial, a 5-week resistance-training program with intentional overreaching on weeks 2 and 5 was implemented. Results indicate that marine phytoplankton prompted positive changes in perceived recovery at post-testing and, while both marine phytoplankton and placebo conditions demonstrated decreased peak and mean rate of force development following the overreaching weeks, placebo remained decreased at post-testing while marine phytoplankton returned to baseline levels. In the rat model, rats were divided into four conditions: (i) control, (ii) exercise, (iii) exercise + marine phytoplankton 2.55 mg·d-1, or (iv) exercise+marine phytoplankton 5.1 mg·d-1. Rats in exercising conditions performed treadmill exercise 5 d·wk-1 for 6 weeks. Marine phytoplankton in exercising rats increased positive and decrease negative myogenic factors regulating satellite cell proliferation. Taken together, marine phytoplankton improved perceptual and functional indices of exercise recovery in an overreaching human model and, mechanistically, this could be driven through cell cycle regulation and a potential to improve protein turnover.


Assuntos
Desenvolvimento Muscular/fisiologia , Força Muscular/fisiologia , Músculo Esquelético/fisiologia , Fitoplâncton , Treinamento Resistido/métodos , Animais , Biomarcadores/sangue , Contagem de Células , Ciclo Celular/fisiologia , Método Duplo-Cego , Feminino , Humanos , Masculino , Condicionamento Físico Animal , Ratos , Ratos Wistar
10.
Nutr Metab Insights ; 13: 1178638820949239, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33061414

RESUMO

BACKGROUND: Muscle mass is an important determinant of metabolic health and physical function. It has previously been demonstrated that the postprandial rise in circulating essential amino acids acts as the main stimulus for muscle protein synthesis (MPS). The current study investigated the postprandial plasma essential amino acid (EAA) and branched-chain amino acid (BCAA) responses of (1) Hydrolyzed whey protein isolate (HWPI) compared to plasma treated non-hydrolyzed whey protein isolate (PT-NHWPI), (2) standard branch-chain amino acids (S-BCAA) compared to plasma treated branch-chained amino acids (PT-BCAA), (3) standard pea protein (S-PP), compared to plasma treated pea protein (PT-PP), and (4) HWPI compared to PT-PP. METHODS: Ten subjects (24.6 ± 5.3 years; 178.8 ± 8.1 cm; 78.6 ± 10.1 kg) participated in a double-blind, randomized, crossover trial comparing four separate protein conditions (HWPI, PT-NHWPI, S-PP, PT-PP). A separate cohort of ten subjects (26.4 ± 7.4 years; 178.8 ± 5.9 cm; 85 ± 12.3 kg) participated in a double-blind randomized, crossover trial comparing two branch-chain amino acid conditions: S-BCAA and PT-BCAA. All conditions were administered following a 7-day washout. Plasma EAA and BCAA concentrations were assessed from blood donated by subjects at pre-consumption, 30-, 60-, 90-, 120-, and 180 minutes post-consumption. RESULTS: Blood plasma levels of total EAA and BCAA concentration were significantly greater in all treated conditions at 30-, 60-, 90-, and 120 minutes post consumption (P < .05). There were no differences between PT-PP and HWPI. DISCUSSION: All proteins significantly elevated EAAs, and BCAAs from basal levels. However, we conclude that the consumption of the treated proteins significantly raises blood levels of EAAs, and BCAAs to a greater extent across multiple dairy, vegan, and isolated BCAA conditions. Moreover, atmospheric plasma treatment of a vegan protein source makes its amino acid response similar to whey. Thus, protein supplementation with that has undergone Ingredient Optimized® atmospheric plasma treatment technology may be highly beneficial for improving the blood plasma amino acid response.

11.
Nutrients ; 12(7)2020 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-32635494

RESUMO

The purpose of this study was to investigate the impact of antioxidant-rich marine phytoplankton supplementation (Oceanix, OCX) on performance and muscle damage following a cross-training event in endurance-trained subjects. Additionally, an animal model was carried out to assess the effects of varying dosages of OCX, with exercise, on intramuscular antioxidant capacity. METHODS: In the human trial, endurance-trained subjects (average running distance = 29.5 ± 2.6 miles × week-1) were randomly divided into placebo (PLA) and OCX (25 mg) conditions for 14 days. The subjects were pre-tested on a one-mile uphill run, maximal isometric strength, countermovement jump (CMJ) and squat jump (SJ) power, and for muscle damage (creatine kinase (CK)). On Day 12, the subjects underwent a strenuous cross-training event. Measures were reassessed on Day 13 and 14 (24 h and 48 h Post event). In the animal model, Wistar rats were divided into four groups (n = 7): (i) Control (no exercise and placebo (CON)), (ii) Exercise (E), (iii) Exercise + OCX 1 (Oceanix, 2.55 mg/day, (iv) Exercise + OCX 2 (5.1 mg/day). The rats performed treadmill exercise five days a week for 6 weeks. Intramuscular antioxidant capacity (superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GSH-Px)) and muscle damage (CK and myoglobin (MYOB) were collected. The data were analyzed using repeated measures ANOVA and t-test for select variables. The alpha value was set at p < 0.05. RESULTS: For the human trial, SJ power lowered in PLA relative to OCX at 24 h Post (-15%, p < 0.05). Decrements in isometric strength from Pre to 48 h Post were greater in the PLA group (-12%, p < 0.05) than in the OCX. Serum CK levels were greater in the PLA compared to the OCX (+14%, p < 0.05). For the animal trial, the intramuscular antioxidant capacity was increased in a general dose-dependent manner (E + Oc2 > E + Oc1 > E > CON). Additionally, CK and MYOB were lower in supplemented compared to E alone. CONCLUSIONS: Phytoplankton supplementation (Oceanix) sustains performance and lowers muscle damage across repeated exercise bouts. The ingredient appears to operate through an elevating oxidative capacity in skeletal muscle.


Assuntos
Antioxidantes/administração & dosagem , Suplementos Nutricionais , Treino Aeróbico/métodos , Músculo Esquelético/efeitos dos fármacos , Condicionamento Físico Animal/fisiologia , Fitoplâncton , Adulto , Animais , Antioxidantes/metabolismo , Catalase/metabolismo , Creatina Quinase/sangue , Relação Dose-Resposta a Droga , Exercício Físico/fisiologia , Feminino , Glutationa Peroxidase/metabolismo , Humanos , Contração Isométrica/efeitos dos fármacos , Masculino , Doenças Musculares/etiologia , Doenças Musculares/prevenção & controle , Mioglobina/metabolismo , Desempenho Físico Funcional , Ratos , Ratos Wistar , Superóxido Dismutase/metabolismo
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