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1.
Nutr Res ; 127: 63-74, 2024 May 23.
Artículo en Inglés | MEDLINE | ID: mdl-38876040

RESUMEN

Betaine supplementation is used by athletes, but its mechanism of action is still not fully understood. We hypothesized that betaine supplementation would increase betaine concentration and alter amino acid profiles in relation to MTHFR genotype and dose in physically active males. The study followed a randomized placebo-controlled cross-over design. Blood samples were collected before and after each supplementation period. Serum was analyzed for amino acid profile, homocysteine, betaine, choline, and trimethylamine N-oxide (TMAO) concentrations. For the washout analysis, only participants starting with betaine were included (n = 20). Statistical analysis revealed no differences in the amino acid profile after betaine supplementation. However, betaine concentration significantly increased after betaine supplementation (from 4.89 ± 1.59 µg/mL to 17.31 ± 9.21 µg/mL, P < .001), with a greater increase observed in MTHFR (C677T, rs180113) T-allele carriers compared to CC (P = .027). Betaine supplementation caused a decrease in homocysteine concentration (from 17.04 ± 4.13 µmol/L to 15.44 ± 3.48 µmol/L, P = .00005) and a non-significant increase in TMAO concentrations (from 0.27 ± 0.20 µg/ml to 0.44 ± 0.70 µg/ml, P = .053), but had no effect on choline concentrations. Serum betaine concentrations were not significantly different after the 21-day washout from the baseline values (baseline: 4.93 ± 1.87 µg/mL and after washout: 4.70 ± 1.70 µg/mL, P = 1.000). In conclusion, betaine supplementation increased betaine and decreased homocysteine concentrations, but did not affect the amino acid profile or choline concentrations in healthy active males. Betaine concentrations may be dependent on MTHFR genotype.

2.
Sci Rep ; 14(1): 3525, 2024 02 12.
Artículo en Inglés | MEDLINE | ID: mdl-38347150

RESUMEN

This study was conducted in two groups of girls with PCOS (polycystic ovary syndrome) categorized as slim (group N) and overweight-to-obese (group Ov/Ob). The study's primary outcome was to assess the impact of a 12-week anti-inflammatory diet (AIDiet) intervention, without energy deficit, on daily diet quality improvement, evaluated according to the KIDMED index. The secondary outcome was improving inflammatory, redox, hormonal, and metabolic statuses. In the study, which was completed by 13 girls from the Ov/Ob group and 19 girls from the N group, a significant improvement in the mean KIDMED score was obtained. Moreover, the intervention significantly improves concentration of total antioxidant capacity (TAC), fasting insulin, and the homeostatic model assessment for insulin resistance (HOMA-IR) index, in the Ov/Ob group, while both groups experienced a reduction in the concentration of interleukin (IL)-1 and IL-6, tumour necrosis factor (TNF-α), and androstenedione. The AIDiet intervention effectively improved the quality of the subjects' diets, which was associated with the improvement of hormonal and immuno-metabolic markers. However, these changes in normal-weight patients were observed regardless of body weight reduction. ClinicalTrials.gov Identifier NCT04738409.


Asunto(s)
Resistencia a la Insulina , Síndrome del Ovario Poliquístico , Femenino , Humanos , Sobrepeso/terapia , Sobrepeso/complicaciones , Síndrome del Ovario Poliquístico/metabolismo , Proyectos Piloto , Dieta , Insulina , Antiinflamatorios , Índice de Masa Corporal
3.
Biol Sport ; 41(1): 17-27, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38188117

RESUMEN

Exercise-induced metabolic processes induce muscle acidification which contributes to a reduction in the ability to perform repeated efforts. Alkalizing agents such as sodium bicarbonate (NaHCO3) prevent large blood pH changes, however, there is no evidence on whether regulation of acid-base balance may also support whole body homeostasis monitored through heamatological and biochemical blood markers in a dose-dependent manner. Thirty Cross-Fit-trained participants were studied in a randomized, multi cross-over, placebo (PLA)-controlled double-blind manner in which they performed a control session (CTRL, without supplementation), three NaHCO3 visits (three different doses) and PLA (sodium chloride in an equimolar amount of sodium as NaHCO3). Each visit consisted of two 30-s Wingate tests separated by CrossFit-specific benchmarks (Wall Balls and Burpees - both performed for 3 min). Blood samples were collected at rest, immediately post-exercise and after 45 min recovery. Significant differences between visits appeared for blood pH, percentage of lymphocytes and granulocytes, red blood cells count and haemoglobin concentration at post-exercise and 45-min recovery, and for white blood cells count, percentage of monocytes, concentration of magnesium and creatinine at 45-min recovery. Most of the observed differences for heamatological and biochemical markers were significant compared to CTRL, but not different after PLA. NaHCO3 supplementation compared to PLA did not significantly affect exercise or recovery shifts in studied blood indicators. However, the changes in these markers after NaHCO3 and PLA in relation to CTRL indicate a possible role of sodium.

4.
Rheumatol Int ; 44(3): 413-423, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38180500

RESUMEN

There is increasing knowledge in the recognition of individuals at risk for progression to rheumatoid arthritis (RA) before the clinical manifestation of the disease. This prodromal phase preceding the manifestation of RA may represent a "window of opportunity" for preventive interventions that may transform the clinical approach to this disease. However, limited evidence exists in support of effective interventions to delay the onset or even halt the manifestation of RA. Given the multifactorial nature of RA development and disease progression, the latest guidelines for established RA stress the use of integrative interventions and multidisciplinary care strategies, combining pharmacologic treatment with non-pharmacological approaches. Accordingly, individuals at risk of RA could be offered an integrative, multifactorial intervention approach. Current data point toward pharmacological intervention reverting the subclinical inflammation and delay in the disease onset. In addition, targeting life style modifiable factors (smoking cessation, dental health, physical activity, and diet) may presumably improve RA prognosis in individuals at risk, mainly by changes in epigenetics, autoantibodies, cytokines profiles, and microbiome. Nonetheless, the benefits of multidisciplinary interventions to halt the manifestation of RA in at-risk individuals remain unknown. As there is a growing knowledge of possible pharmacological intervention in the preclinical phase, this narrative review aims to provide a comprehensive overview of non-pharmacological treatments in individuals at risk of RA. Considering the mechanisms preceding the clinical manifestation of RA we explored all aspects that would be worth modifying and that would represent an integrative non-pharmacological care for individuals at risk of RA.


Asunto(s)
Artritis Reumatoide , Humanos , Artritis Reumatoide/terapia , Artritis Reumatoide/tratamiento farmacológico , Inflamación , Autoanticuerpos , Pronóstico , Estilo de Vida
5.
J Int Soc Sports Nutr ; 21(1): 2301384, 2024 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38226646

RESUMEN

BACKGROUND: Caffeine (CAF) ingestion improves performance in a broad range of exercise tasks. Nevertheless, the CAF-induced, dose-dependent effect on discipline-specific performance and cognitive functions in CrossFit/High-Intensity Functional Training (HIFT) has not been sufficiently investigated. The aim of this study was to evaluate the effect of acute supplementation of three different doses of CAF and placebo (PLA) on specific performance, reaction time (RTime), postural stability (PStab), heart rate (HR) and perceived exertion (RPE). METHODS: In a randomized double-blind placebo-controlled crossover design, acute pre-exercise supplementation with CAF (3, 6, or 9 mg/kg body mass (BM)) and PLA in 26 moderately trained CrossFit practitioners was examined. The study protocol involved five separate testing sessions using the Fight Gone Bad test (FGB) as the exercise performance evaluation and biochemical analyses, HR and RPE monitoring, as well as the assessment of RTime and PStab, with regard to CYP1A2 (rs762551) and ADORA2A (rs5751876) single nucleotide polymorphism (SNP). RESULTS: Supplementation of 6 mgCAF/kgBM induced clinically noticeable improvements in FGBTotal results, RTime and pre-exercise motor time. Nevertheless, there were no significant differences between any CAF doses and PLA in FGBTotal, HRmax, HRmean, RPE, pre/post-exercise RTime, PStab variables or pyruvate concentrations. Lactate concentration was higher (p < 0.05) before and after exercise in all CAF doses than in PLA. There was no effect of CYP1A2 or ADORA2A SNPs on performance. CONCLUSIONS: The dose-dependent effect of CAF supplementation appears to be limited to statistically nonsignificant but clinically considered changes on specific performance, RTime, PStab, RPE or HR. However, regarding practical CAF-induced performance implications in CrossFit/HIFT, 6 mgCAF/kgBM may be supposed as the most rational supplementation strategy.


Asunto(s)
Rendimiento Atlético , Cafeína , Humanos , Cafeína/farmacología , Estudios Cruzados , Citocromo P-450 CYP1A2 , Tiempo de Reacción , Rendimiento Atlético/fisiología , Ácido Láctico , Método Doble Ciego , Suplementos Dietéticos , Poliésteres
6.
Sci Rep ; 13(1): 22423, 2023 12 16.
Artículo en Inglés | MEDLINE | ID: mdl-38104206

RESUMEN

Recent advances in knowledge suggest that micro- and nanoplastics pose a threat to plant health, however, the responses of plants to this stressor are not well-known. Here we examined the response of plant cell defence mechanisms to nanoparticles of commonly used plastic, polystyrene. We used plant cell cultures of widely cultivated plants, the monocots wheat and barley (Triticum aestivum L., Hordeum vulgare L.) and the dicots carrot and tomato (Daucus carota L., Solanum lycopersicum L.). We measured the activities of enzymes involved in the scavenging of reactive oxygen species and nonenzymatic antioxidants and we estimated potential damages in plant cell structures and functioning via lipid peroxidation and DNA methylation levels. Our results demonstrate that the mode of action of polystyrene nanoparticles on plant cells involves oxidative stress. However, the changes in plant defence mechanisms are dependent on plant species, exposure time and nanoplastic concentrations. In general, both monocots showed similar responses to nanoplastics, but the carrot followed more the response of monocots than a second dicot, a tomato. Higher H2O2, lipid peroxidation and lower enzyme activities scavenging H2O2 suggest that tomato cells may be more susceptible to polystyrene-induced stress. In conclusion, polystyrene nanoplastics induce oxidative stress and the response of the plant defense mechanisms involving several chain reactions leading to oxidoreductive homeostasis.


Asunto(s)
Nanopartículas , Poliestirenos , Células Vegetales , Peróxido de Hidrógeno , Microplásticos , Antioxidantes , Plantas , Mecanismos de Defensa
7.
Nutrients ; 15(20)2023 Oct 23.
Artículo en Inglés | MEDLINE | ID: mdl-37892559

RESUMEN

The current systematic review (PROSPERO registration no. CRD42022334707) of observational (OS) and interventional studies (IS) aimed at evaluating the state of scientific knowledge on the basics of sports nutrition, framing discipline-specific dietary recommendations, and indicating potential directions for future studies in various age, experience level, and able-bodied abilities groups of basketball players (BP). A systematic search of PubMed, SPORTDiscus, and Web of Science ended on 20 December 2022. Records were excluded if reporting studies on animals, sport disciplines other than basketball, or supplementation protocols other than those related to macronutrients and hydration manipulations. Risk of bias (RoB) was evaluated using Cochrane RoB_2 tools, 'JBI checklist for prevalence studies', and 'Quality assessment tool for before-after (pre-post) studies with no control group'. The relevant data was synthesized in tables and a narrative review was performed. Seventy-two records were included (2581 participants): 63 were on able-bodied BP (2433 participants) and 9 on para-athlete players (148 participants); 45 records were OS and 27 IS. The review disclosed widespread poor nutritional habits and knowledge and shortages in applying adequate nutritional and hydration practices in BP. Moreover, the systematic review revealed the lack of a sufficient number of investigations delivering reliable proof for framing discipline-specific and evidence-based recommendations on the basics of sports nutrition in basketball.


Asunto(s)
Baloncesto , Paratletas , Ciencias de la Nutrición y del Deporte , Humanos , Dieta , Predicción
8.
J Int Soc Sports Nutr ; 20(1): 2231411, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37409757

RESUMEN

BACKGROUND: Because betaine (BET) supplementation may improve muscular strength and endurance, it seems plausible that BET will also influence CrossFit performance (CF). PURPOSE: The aim of this study was to evaluate the effects of three weeks of BET supplementation on body composition, CF performance, muscle power in the Wingate anaerobic test (WAnT), and the concentrations of selected hormones. The secondary aims were to analyze the effectiveness of two different BET doses (2.5 and 5.0 g/d) and their interaction with the methylenetetrahydrofolate reductase (MTHFR) genotype. METHODS: The study was designed in a double-blinded randomized cross-over fashion. Forty-three CF practitioners completed the entire study. CF performance was measured using the Fight Gone Bad (FGB) workout and muscle power was evaluated in a 30-second WAnT. Body composition was determined by air-displacement plethysmography. Blood was drawn to assess hormone concentrations. The C677T single nucleotide polymorphism (rs180113) in the MTHFR gene was analyzed. RESULTS: FGB total improved with BET by 8.7 ± 13.6% (p < 0.001), but no significant changes were observed with placebo (- 0.4 ± 10.0%, p = 0.128). No changes were also observed in WAnT and body composition. After BET supplementation testosterone concentration increased by 7.0 ± 15.4% with BET (p = 0.046) (no change with placebo: 1.5 ± 19.6%, p = 0.884) but had no effect on concentrations of insulin-like growth factor or cortisol. Finally, there were no significant interactions between MTHFR genotype and BET dose in any outcome. CONCLUSIONS: BET supplementation may improve CF performance and increase testosterone concentration. However, there was no evidence of a difference between dosages (2.5 and 5.0 g/d) and MTHFR genotypes. The trial was registered on clinicaltrials.gov (NCT03702205) on 10 October 2018.


Asunto(s)
Betaína , Testosterona , Humanos , Betaína/farmacología , Estudios Cruzados , Método Doble Ciego , Suplementos Dietéticos
9.
Trends Plant Sci ; 28(10): 1144-1165, 2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-37331842

RESUMEN

The discovery of the CRISPR/Cas genome-editing system has revolutionized our understanding of the plant genome. CRISPR/Cas has been used for over a decade to modify plant genomes for the study of specific genes and biosynthetic pathways as well as to speed up breeding in many plant species, including both model and non-model crops. Although the CRISPR/Cas system is very efficient for genome editing, many bottlenecks and challenges slow down further improvement and applications. In this review we discuss the challenges that can occur during tissue culture, transformation, regeneration, and mutant detection. We also review the opportunities provided by new CRISPR platforms and specific applications related to gene regulation, abiotic and biotic stress response improvement, and de novo domestication of plants.


Asunto(s)
Sistemas CRISPR-Cas , Edición Génica , Sistemas CRISPR-Cas/genética , Fitomejoramiento , Genoma de Planta/genética , Productos Agrícolas/genética , Plantas Modificadas Genéticamente/genética
10.
Sci Rep ; 13(1): 7081, 2023 05 01.
Artículo en Inglés | MEDLINE | ID: mdl-37127791

RESUMEN

This double-blind placebo-controlled cross-over study utilized comprehensive monitoring of blood bicarbonate (HCO3¯) kinetics and evaluation of gastrointestinal (GI) upset to determine their impact on an ergogenic potential of sodium bicarbonate (SB) co-ingested with carbohydrate (CHO). Nineteen CrossFit athletes performed 6 bouts of 15 s Wingate Anaerobic Test (WAnT) 90 min post-ingestion of 0.4 g·kg-1 body mass (BM) of SB (SB + CHO treatment) or PLA (PLA + CHO treatment) with 15 g CHO. Blood HCO3¯ concentration was evaluated at baseline, 30-, 60-, 75- and 90 min post-ingestion, in between WAnT bouts, and 3 and 45 min post-exercise, while GI upset at 120 min after protocol started. Control (no supplementation; CTRL) procedures were also performed. An effective elevation of extra-cellular buffering capacity was observed 60-90 min post-ingestion of SB + CHO. At mean peak blood HCO3¯, or at start of exercise an increase > 6 mmol·L-1 in HCO3¯ was noted in 84% and 52.6% participants, respectively. SB + CHO did not prevent performance decrements in WAnT bouts. There were no significant relationships between changes in blood HCO3¯ and WAnTs' performance. Total GI was significantly higher in SB + CHO compared to CTRL, and stomach problems in SB + CHO compared to CTRL and PLA + CHO. There were inverse associations between peak- (p = 0.031; r = - 0.495), average- (p = 0.002; r = - 0.674) and minimum power (p = 0.008; r = - 0.585) and total GI upset, as well as average power and severe GI distress (p = 0.042; r = - 0.471) at SB + CHO. The implemented dose of SB + CHO was effective in improving buffering capacity, but did not prevent decrements in WAnTs' performance. GI side effects were crucial in affecting the ergogenic potential of SB and thus must be insightfully monitored in future studies.


Asunto(s)
Rendimiento Atlético , Enfermedades Gastrointestinales , Humanos , Bicarbonato de Sodio/efectos adversos , Bicarbonatos , Estudios Cruzados , Enfermedades Gastrointestinales/inducido químicamente , Poliésteres , Método Doble Ciego
11.
Int J Mol Sci ; 24(3)2023 Jan 21.
Artículo en Inglés | MEDLINE | ID: mdl-36768486

RESUMEN

Despite intensive optimization efforts, developing an efficient sequence-specific CRISPR/Cas-mediated genome editing method remains a challenge, especially in polyploid cereal species such as wheat. Validating the efficacy of nuclease constructs prior to using them in planta is, thus, a major step of every editing experiment. Several construct evaluation strategies were proposed, with PEG-mediated plasmid transfection of seedling-derived protoplasts becoming the most popular. However, the usefulness of this approach is affected by associated construct copy number bias and chromatin relaxation, both influencing the outcome. Therefore, to achieve a reliable evaluation of CRISPR/Cas9 constructs, we proposed a system based on an Agrobacterium-mediated transformation of established wheat cell suspension cultures. This system was used for the evaluation of a CRISPR/Cas9 construct designed to target the ABA 8'-hydroxylase 1 gene. The efficiency of editing was verified by cost-effective means of Sanger sequencing and bioinformatic analysis. We discuss advantages and potential future developments of this method in contrast to other in vitro approaches.


Asunto(s)
Sistemas CRISPR-Cas , Triticum , Triticum/genética , Edición Génica/métodos , Agrobacterium/genética , Técnicas de Cultivo de Célula
12.
Metabolites ; 12(8)2022 Aug 07.
Artículo en Inglés | MEDLINE | ID: mdl-36005603

RESUMEN

Betaine (BET) supplementation decreases homocysteine concentration in plasma, but it may also have an adverse effect on health by increasing blood lipid concentrations, at least in overweight and obese individuals. The aim of this study was to evaluate the effect of BET supplementation on the lipid profile and concentrations of homocysteine, inflammatory cytokines, and liver enzymes in physically active, healthy males. This was a randomized, placebo (PL)-controlled, double-blinded, crossover trial. BET (2.5 or 5.0 g/d) was administered for 21 days. Before and after supplementation with BET or PL, anthropometric measurements and blood were collected in a fasted state. Our results show that BET supplementation significantly decreased homocysteine concentration (from 17.1 ± 4.0 µmol/L before BET to 15.6 ± 3.5 µmol/L after BET, p = 0.009, η2 = 0.164). However, the intervention had no effect on total cholesterol, low-density lipoprotein cholesterol, high-density lipoprotein cholesterol, triacylglycerol, interleukins 1ß and 6, and tumour necrosis factor α concentrations, or alanine and aspartate activities. In addition, there were no interactions between the MTHFR genotype and BET dose. In conclusion, BET supplementation may be beneficial for homocysteine concentration in healthy, physically active males, with no detrimental effect on lipid profile.

13.
Nutrients ; 14(4)2022 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-35215544

RESUMEN

This interventional study examined the effect of a four-week vegan diet (VegD) during a four-week high-intensity functional training (HIFT) on performance, training results and blood biochemical indices in female (n = 12) and male (n = 8) moderate-trained CrossFit participants. The whole study group performed the maximum number of repetitions with a load of 70% one repetition-maximum (1RM) and a modified Fight Gone Bad (FGBMod) test before and after a dietary intervention (the group was divided to follow a VegD or a traditional mixed diet (MixD)) in a randomised and parallel design. Pre-exercise resting blood samples were also analysed. There was a significant improvement in the number of repetitions performed at a load corresponding to 70% of 1RM in the classic squat in the MixD group (p < 0.001), and in the classic deadlift in the VegD group (p = 0.014). Furthermore, there was a significant improvement in the results of the FGBMod performance test after a MixD. Moreover, an improvement in some exercises in the modified FGBMod test (Wall Ball after the VegD and the MixD, and rowing after the MixD) was also observed. However, differences between the MixD and the VegD groups were not clinically relevant. In conclusion, the short-term study conducted here indicated that a VegD in HIFT training positively affects strength endurance in the classic deadlift but is unlikely to be more beneficial in improving performance than a MixD.


Asunto(s)
Dieta Vegana , Entrenamiento de Fuerza , Ejercicio Físico , Femenino , Humanos , Masculino , Fuerza Muscular , Músculo Esquelético
14.
Eur J Sport Sci ; 22(5): 745-754, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-33487131

RESUMEN

ABSTRACTSodium bicarbonate (SB) is considered an effective ergogenic supplement for improving high-intensity exercise capacity and performance, although recent data suggests that women may be less amenable to its ergogenic effects than men. Currently, an apparent paucity of data on women means no consensus exists on whether women benefit from SB supplementation. The aim of the current study was to quantify the proportion of the published literature on SB supplementation that includes women, and to synthesise the evidence regarding its effects on blood bicarbonate and exercise performance in women by performing a systematic review and meta-analysis. Electronic searches of the literature were undertaken using three databases (MEDLINE, Embase, SPORTDiscus) to identify relevant articles. All meta-analyses were performed within a Bayesian framework. A total of 149 SB articles were identified, 11 of which contained individual group data for women. Results indicated a pooled blood bicarbonate increase of 7.4 [95%CrI: 4.2-10.4 mmol·L-1] following supplementation and a pooled standardised exercise effect size of 0.37 [95%CrI: -0.06-0.92]. The SB literature is skewed, with only 20% (30 studies) of studies employing female participants, of which only 11 studies (7.4%) provided group analyses exclusively in women. Despite the small amount of available data, results are consistent in showing that SB supplementation in women leads to large changes in blood bicarbonate and that there is strong evidence for a positive ergogenic effect on exercise performance that is likely to be small to medium in magnitude.HighlightsThis study aimed to quantify the proportion of the published literature on sodium bicarbonate supplementation that includes women and to synthesise the evidence regarding its ergogenic effect on women, using a systematic review and meta-analytic approach.The sodium bicarbonate literature is skewed, with only 30 studies (20%) employing female participants, of which only 11 studies (7.4%) provided group analyses exclusively in women.Despite the small amount of available data, results are consistent in showing that sodium bicarbonate supplementation in women leads to large changes in blood bicarbonate and that there is strong evidence for a positive ergogenic effect on exercise performance that is likely small to medium in magnitude.Based on these findings, we do not believe there is any evidence to support sex-specific sodium bicarbonate dosing recommendations and that current recommendations of 0.2-0.3 g·kg-1BM of SB taken 60-180 min prior to high-intensity exercise appear appropriate for the female athlete.


Asunto(s)
Rendimiento Atlético , Sustancias para Mejorar el Rendimiento , Atletas , Teorema de Bayes , Bicarbonatos/farmacología , Suplementos Dietéticos , Femenino , Humanos , Masculino , Sustancias para Mejorar el Rendimiento/farmacología , Bicarbonato de Sodio/farmacología
15.
Sports Med ; 52(3): 505-526, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-34687438

RESUMEN

BACKGROUND: Extracellular buffering supplements [sodium bicarbonate (SB), sodium citrate (SC), sodium/calcium lactate (SL/CL)] are ergogenic supplements, although questions remain about factors which may modify their effect. OBJECTIVE: To quantify the main effect of extracellular buffering agents on exercise outcomes, and to investigate the influence of potential moderators on this effect using a systematic review and meta-analytic approach. METHODS: This study was designed in accordance with Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Three databases were searched for articles that were screened according to inclusion/exclusion criteria. Bayesian hierarchical meta-analysis and meta-regression models were used to investigate pooled effects of supplementation and moderating effects of a range of factors on exercise and biomarker responses. RESULTS: 189 articles with 2019 participants were included, 158 involving SB supplementation, 30 with SC, and seven with CL/SL; four studies provided a combination of buffering supplements together. Supplementation led to a mean estimated increase in blood bicarbonate of + 5.2 mmol L-1 (95% credible interval (CrI) 4.7-5.7). The meta-analysis models identified a positive overall effect of supplementation on exercise capacity and performance compared to placebo [ES0.5 = 0.17 (95% CrI 0.12-0.21)] with potential moderating effects of exercise type and duration, training status and when the exercise test was performed following prior exercise. The greatest ergogenic effects were shown for exercise durations of 0.5-10 min [ES0.5 = 0.18 (0.13-0.24)] and > 10 min [ES0.5 = 0.22 (0.10-0.33)]. Evidence of greater effects on exercise were obtained when blood bicarbonate increases were medium (4-6 mmol L-1) and large (> 6 mmol L-1) compared with small (≤ 4 mmol L-1) [ßSmall:Medium = 0.16 (95% CrI 0.02-0.32), ßSmall:Large = 0.13 (95% CrI - 0.03 to 0.29)]. SB (192 outcomes) was more effective for performance compared to SC (39 outcomes) [ßSC:SB = 0.10 (95% CrI - 0.02 to 0.22)]. CONCLUSIONS: Extracellular buffering supplements generate large increases in blood bicarbonate concentration leading to positive overall effects on exercise, with sodium bicarbonate being most effective. Evidence for several group-level moderating factors were identified. These data can guide an athlete's decision as to whether supplementation with buffering agents might be beneficial for their specific aims.


Asunto(s)
Tolerancia al Ejercicio , Sustancias para Mejorar el Rendimiento , Teorema de Bayes , Suplementos Dietéticos , Humanos , Sustancias para Mejorar el Rendimiento/farmacología , Bicarbonato de Sodio/farmacología
16.
Nutrients ; 15(1)2022 Dec 20.
Artículo en Inglés | MEDLINE | ID: mdl-36615663

RESUMEN

The triathlon is a demanding endurance multisport, which may strongly affect the nutritional status of athletes. The aim of this study was to find whether there are any differences in energy value and nutrient intake, body mass and body composition, aerobic performance and hair mineral status between training and competition periods and to assess whether there is a link between hair mineral content and physical capacity and nutrition. This observational study covered 20 triathletes aged 32 ± 7 years. The results of our study indicated performance improvement during the competition period (longer time to exhaustion (p = 0.025) and lower maximal oxygen uptake at the ventilatory threshold (%VO2max_VT; p = 0.047)). However, no differences were recorded in nutrition and body composition between two training vs. competition periods. There was a significant depletion in hair iron content during the competition period (p = 0.010). Furthermore, there were significant relationships between hair calcium content and absolute maximal oxygen uptake and %VO2max_VT during the training period. It is necessary to introduce nutritional education in the group of triathletes focused on exercise-oriented nutritional periodization following the requirements of the training and competition periods, thus preventing the risk of nutrient deficiencies.


Asunto(s)
Consumo de Oxígeno , Carrera , Humanos , Natación , Ciclismo , Composición Corporal , Ingestión de Energía , Frecuencia Cardíaca , Minerales , Oxígeno , Resistencia Física
17.
Int J Mol Sci ; 22(13)2021 Jun 29.
Artículo en Inglés | MEDLINE | ID: mdl-34210100

RESUMEN

Cas endonuclease-mediated genome editing provides a long-awaited molecular biological approach to the modification of predefined genomic target sequences in living organisms. Although cas9/guide (g)RNA constructs are straightforward to assemble and can be customized to target virtually any site in the plant genome, the implementation of this technology can be cumbersome, especially in species like triticale that are difficult to transform, for which only limited genome information is available and/or which carry comparatively large genomes. To cope with these challenges, we have pre-validated cas9/gRNA constructs (1) by frameshift restitution of a reporter gene co-introduced by ballistic DNA transfer to barley epidermis cells, and (2) via transfection in triticale protoplasts followed by either a T7E1-based cleavage assay or by deep-sequencing of target-specific PCR amplicons. For exemplification, we addressed the triticale ABA 8'-hydroxylase 1 gene, one of the putative determinants of pre-harvest sprouting of grains. We further show that in-del induction frequency in triticalecan beincreased by TREX2 nuclease activity, which holds true for both well- and poorly performing gRNAs. The presented results constitute a sound basis for the targeted induction of heritable modifications in triticale genes.


Asunto(s)
Sistema Enzimático del Citocromo P-450/metabolismo , Edición Génica/métodos , Proteínas de Plantas/metabolismo , Triticale/metabolismo , Sistemas CRISPR-Cas , Sistema Enzimático del Citocromo P-450/genética , Genes Reporteros , Mutación INDEL , Mutagénesis Sitio-Dirigida , Proteínas de Plantas/genética , Transfección , Triticale/genética
18.
J Int Soc Sports Nutr ; 18(1): 48, 2021 Jun 14.
Artículo en Inglés | MEDLINE | ID: mdl-34127014

RESUMEN

BACKGROUND: This study aimed to investigate the effect of multi-ingredient intra- (BA) versus extra- (ALK) cellular buffering factor supplementation, combined with the customary intake of branched-chain amino acids (BCAA) and creatine malate (TCM), on body composition, exercise variables, and biochemical and hematological parameters in 9 elite taekwondo athletes. METHODS: Eight-week randomized double-blind crossover BA (5.0 g·day-1 of ß-alanine) versus ALK (0.07 g·kgFFM-1·day-1 of sodium bicarbonate) supplementation combined with BCAA (0.2 g·kgFFM-1·day-1) and TCM (0.05 g·kgFFM-1·day-1) during a standard 8-week taekwondo training period was implemented. In the course of the experiment, body composition (dual X-ray absorptiometry), aerobic capacity (ergospirometric measurements during an incremental treadmill test until exhaustion), and exercise blood biomarkers concentrations were measured. Data were analyzed using repeated measures within-between interaction analysis of variance with the inclusion of experimental supplementation order. RESULTS: The maximum post-exercise blood ammonia concentration decreased in both groups after supplementation (from 80.3 ± 10.6 to 72.4 ± 10.2 µmol∙L-1, p = 0.013 in BA; from 81.4 ± 8.7 to 74.2 ± 8.9 µmol∙L-1, p = 0.027 in ALK), indicating reduced exercise-related adenosine triphosphate degradation. However, no differences were found in body composition, aerobic capacity, blood lactate concentration, and hematological parameters after neither BA (combined with BCAA and TCM) nor ALK (combined with BCAA and TCM) supplementation. CONCLUSIONS: In highly trained taekwondo athletes, neither extra- nor intracellular buffering enhancement resulting from BA and ALK supplementation, combined with BCAA and TCM treatment, affects body mass and composition, maximum oxygen uptake, and hematological indices, even though certain advantageous metabolic adaptations can be observed.


Asunto(s)
Aminoácidos de Cadena Ramificada/administración & dosificación , Amoníaco/sangre , Rendimiento Atlético/fisiología , Creatina/administración & dosificación , Suplementos Dietéticos , Artes Marciales/fisiología , Bicarbonato de Sodio/administración & dosificación , beta-Alanina/administración & dosificación , Adaptación Fisiológica , Biomarcadores/sangre , Composición Corporal , Estudios Cruzados , Método Doble Ciego , Humanos
19.
Sci Rep ; 11(1): 7263, 2021 03 31.
Artículo en Inglés | MEDLINE | ID: mdl-33790372

RESUMEN

Cross-training is a high-intensity functional training (HIFT) with multiple workout modalities. Despite the increasing number of studies in HIFT, there is still no validated test to measure its specific performance. It would also be advisable to determine whether selected cross-training workouts can implement a stimulus corresponding to maximize aerobic work. For these reasons, the purpose of our study was to evaluate the repeatability and reliability of Fight Gone Bad (FGB) workout and to assess its relationship with aerobic fitness. Twenty-one cross-training participants (9 females) finished the study protocol which included three two-day measurement sessions separated by 10 days. During each session, participants had their body composition measured, and they performed two exercise tests. The first test was an incremental cycling test to measure aerobic fitness, and the second was a cross-training specific FGB workout performed the next day. Reliability and repeatability were calculated from the three measurements. The total FGB Score (FGBTOTAL) showed excellent reliability (ICC 0.9, SEM 6%). Moreover, FGBTOTAL was strongly correlated with aerobic fitness (i.e., time to exhaustion (Texh, R2 = 0.72), maximal workload (Wmax, R2 = 0.69), time to gas exchange threshold (TGET, R2 = 0.68), and peak oxygen uptake (VO2peak, R2 = 0.59). We also found that agreement between standardized FGB and standardized aerobic performance indices such as Texh, VO2peak, Wmax, maximum heart rate, TGET, and workload at gas exchange threshold was high by the Bland-Altman method. In conclusion, FGB is a reliable test that can be used in order to measure changes in cross-training performance caused by an intervention. Moreover, FGB is strongly correlated to aerobic fitness.

20.
Nutrients ; 13(3)2021 Mar 06.
Artículo en Inglés | MEDLINE | ID: mdl-33800770

RESUMEN

This single-arm interventional study examined the effect of a 4-week ketogenic diet (KD) on aerobic capacity and discipline-specific performance in female (n = 11) and male (n = 11) CrossFit-trained athletes. The participants performed incremental cycling (ICT) and Fight Gone Bad (FGB) tests after consuming a customary diet and a KD. Pre- and post-ICT exercise blood samples were also analysed. Consuming a KD had a slight impact on aerobic capacity and no relevant effect on CrossFit-specific performance. In females, consuming a KD led to an 10.4% decrease in peak oxygen uptake during the ICT (p = 0.027) and resulted in certain alterations in haematological parameters (haemoglobin (HGB), mean corpuscular HGB, and mean corpuscular HGB concentration). Furthermore, in males, alanine aminotransferase activity increased with a simultaneous improvement in the post-ICT blood acid-base balance after consuming a KD. The pre-exercise bilirubin concentration was also elevated in the entire group after consuming a KD. In conclusion, female CrossFit-trained athletes seem to be prone to aerobic performance decrements and increased risk of developing haematological disturbances when consuming a KD. In males who consumed a KD, there was an undesirable alanine aminotransferase elevation and a small tendency towards improved acid-base status. Moreover, consuming a KD had no effect on discipline-specific performance in CrossFit-trained athletes.


Asunto(s)
Rendimiento Atlético/fisiología , Ciclismo/fisiología , Dieta Cetogénica/efectos adversos , Entrenamiento de Intervalos de Alta Intensidad , Equilibrio Ácido-Base , Adolescente , Adulto , Alanina Transaminasa/sangre , Bilirrubina/sangre , Índices de Eritrocitos/fisiología , Femenino , Hemoglobinas/metabolismo , Humanos , Masculino , Consumo de Oxígeno , Factores Sexuales , Adulto Joven
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