The Society of Information and the European Citizens' Perception of Climate Change: Natural or Anthropological Causes.

The scientific community has reached a consensus on humans' important role as causative agents of climate change; however, branches of society are still sceptical about this. Climate change is a key issue for humanity and only the commitment to change human attitudes and lifestyles, at the global level, can be effective in its mitigation. With this purpose, it is important to convey the right message and prevent misinformation to manipulate people's minds. The present study aims to understand the factors shaping European citizens' thoughts on the causes of climate change. Using data from the European Social Survey 10 collected in 2022, we fitted statistical models using the people's thoughts on causes of climate change (natural, anthropogenic or both) as dependent variables. As independent variables, we used the impact of the media through time spent on news and time spent on the internet, level of education, level of trust in scientists, awareness of online or mobile misinformation and gender. We concluded that the typical European citizen who believes in anthropogenic causes of climate change is a female, is more literate, trusts more in scientists, is younger, spends more time reading the news and has more awareness of misinformation presence in online and mobile communications.

Determining the optimal interval between neoadjuvant radiochemotherapy and surgery in rectal cancer: a retrospective cohort study.

INTRODUCTION: In locally advanced rectal cancer, the optimal interval between completion of neoadjuvant radiochemotherapy (RT-ChT) and surgical resection remains unclear due to contradictory data on the benefits of extending this interval. Therefore, the aim of this retrospective study was to determine the impact of this interval on outcomes in patients treated for rectal cancer at our center. METHODS: We retrospectively reviewed 382 consecutive patients treated for stage II/III rectal cancer between October 1, 2012, and December 31, 2017. We evaluated four different cut-off points (56, 63, 70, and 77 days) to determine which had the greatest impact on treatment outcomes. RESULTS: The median time between completion of RT-ChT and surgery was 67.2 days (range, 28-294). Intervals > 8 weeks (56 days) were associated with worse therapeutic outcomes. Specifically, an interval ≥ 77 days was associated with a significant decrease in overall survival (OS; 84% vs. 70%; p = 0.004), which is why we selected this interval for the comparative analysis. Several outcome variables were significantly better in the short interval (< 77 days) group, including margin involvement (5.2% vs. 13.9%; p = 0.01), sphincter preservation (78% vs. 59.3%; p = 0.003), and distant dissemination (22.6% vs. 32.5%; p = 0.04). No significant between-group differences were found in complete/nearly complete response rates (19.2% vs. 24.4%; p = 0.3). Time to surgery was statistically significant on both the univariate and multivariate analyses. CONCLUSIONS: Our findings suggest that surgery should not be delayed more than 8 weeks (56 days) after neoadjuvant treatment. An interval > 8 weeks should only be considered in patients who demonstrate a good response to neoadjuvant RT-ChT.

Effects of Beef Protein Supplementation in Male Elite Triathletes: A Randomized, Controlled, Double-Blind, Cross-Over Study.

OBJECTIVE: Beef protein extracts are growing in popularity in recent years due to their purported anabolic effects as well as to their potential benefits on hematological variables. The present randomized, controlled, double-blind, cross-over study aimed to analyze the effects of beef protein supplementation on a group of male elite triathletes (Spanish National Team). METHODS: Six elite triathletes (age, 21 ± 3 years; VO2max, 71.5 ± 3.0 ml·kg·min-1) were randomly assigned to consume daily either 25 g of a beef supplement (BEEF) or an isoenergetic carbohydrates (CHO) supplement for 8 weeks, with both conditions being separated by a 5-week washout period. Outcomes, including blood analyses and anthropometrical measurements, were assessed before and after each 8-week intervention. RESULTS: No effects of supplement condition were observed on body mass nor on skinfold thicknesses, but BEEF induced significant and large benefits over CHO in the thigh cross-sectional area (3.02%, 95%CI = 1.33 to 4.71%; p = 0.028, d = 1.22). Contrary to CHO, BEEF presented a significant increase in vastus lateralis muscle thickness (p = 0.046), but differences between conditions were not significant (p = 0.173, d = 0.87). Although a significantly more favorable testosterone-to-cortisol ratio (TCR) was observed for BEEF over CHO (37%, 95% CI = 5 to 68%; p = 0.028, d = 1.29), no significant differences were found for the hematological variables (i.e., iron, ferritin, red blood cell count, hemoglobin or hematocrit). CONCLUSION: Beef protein supplementation seems to facilitate a more favorable anabolic environment (i.e., increased TCR and muscle mass) in male elite triathletes, with no impact on hematological variables.

Single-stage approach for the management of choledocolithiasis with concomitant cholelithiasis. Implementation of a protocol in a secondary hospital.

BACKGROUND: Current evidence shows that single-stage treatment of concomitant choledocholithiasis and cholelithiasis is as effective and safe as two-stage treatment. However, several studies suggest that single-stage approach requires shorter hospitalization time and is more cost-effective than the two-stage approach, even though it requires considerable training. This study aimed to evaluate the implementation of a protocol for managing concomitant choledocholithiasis and cholelithiasis using single-stage treatment. METHODS: A prospective cohort study of patients diagnosed with cholelithiasis and choledocholithiasis who were treated with the single-stage treatment - transcystic instrumentation, choledocotomy or intraoperative endoscopic retrograde cholangiopancreatography (ERCP) - between September 2010 and June 2017 was assessed. The primary outcomes were complications, hospital stay, operative time and recurrence rate. RESULTS: 164 patients were enrolled. 141 (86%) were operated laparoscopically. Preoperatively diagnosed stones were not found by intraoperative imaging or disappeared after "flushing" in 38 patients (23.2%). Surgical approach was transcystic in 45 patients (27.41%), choledochotomy in 74 (45.1%), intraoperative ERCP in 4 (2.4%), and bilioenteric derivation in 3 (1.8%). Mean hospitalization stay was 4.4 days. Mean operative time was 166 min 27 patients (16.5%) had complications and 1 patient was exitus (0.6%). Recurrence rate was 1.2%. CONCLUSIONS: Single-stage approach is a safe and effective management option for concomitant cholelithiasis and choledocolithiasis. Furthermore, a significant number of common bile duct stones pass spontaneously to duodenum or can benefit from a transcystic approach, with presumable low morbidity and cost-efficiency.

Advancing arteriovenous fistula needling: The role of physical exam and doppler ultrasound.

BACKGROUND: The success of haemodialysis (HD) critically depends on the effective use of arteriovenous fistulas (AVFs). The precise needling technique is vital to minimise complications and ensure functional vascular access. OBJECTIVE: This study assesses the effectiveness of a nursing consultation protocol, which integrates physical examination (PE) with Doppler Ultrasound (DUS), in preparing patients for the first AVF needling. DESIGN/PARTICIPANTS: A cross-sectional analysis at a Portuguese National Health Service Hospital engaged thirty new HD patients, four HD needling experienced nurses and one HD vascular access nurse. This study examines the accuracy of PE in assessing the matured AVF by the four nurses compared to a trained vascular access nurse encompassing systematic PE and DUS. MEASUREMENTS: The primary data incorporated AVF characteristics derived from PE (inspection, palpation, and auscultation) and DUS findings (vein depth, diameter, and blood flow). A secondary focus was evaluating the change in nurses' perceived needling complexity following the nursing consultation. RESULTS: The nursing consultation significantly enhanced the identification of crucial AVF features, such as accessory veins (p = 0.002), and improved the accuracy of AVF morphology assessments. This led to identifying longer needling tracks (p = 0.031) and a higher number of safe needling points (p = 0.016). Nurses reported a notable reduction in perceived complexity and potential adverse events following this method (p = 0.027). CONCLUSIONS: Integrating structured PE with DUS in a nursing consultation framework significantly improves the preparation for AVF needling. This approach enhances the efficiency and safety of AVF needling and boosts nurse confidence and patient care in HD settings.

Investigating the relationship between feed and helminthic burden of captive birds of prey in Hong Kong.

The life cycle of most parasitic helminthes is related to their hosts feeding habits. Thus we need to investigate the impact of diet on the host's helminthic parasite burden. Not many studies in captive raptors have been conducted and published regarding parasitic infections. The aim of this study is to evaluate the helminthic burden of raptors kept in captivity and establish a relationship with the feed provided. A total of N = 51 different species of captive birds of prey were fed different diets consisting in different combinations of day old chicks, chicken breast, whole chicken carcass and mice. Their feces were sampled and the parasite burden was determined. A negative binomial model was successfully fitted to the data and the feeds "mice" (P < 0.001) and "whole chicken carcass" (P < 0.001) significantly contributed to an increase in the observed burden. Significant differences were also found between species (P < 0.001). Raptors fed adult animal carcasses and offal may explain the increase in the observed burden as these feeds have a larger probability of being contaminated by a larger variety of helminthic fauna.

Investigating the relationship between inbreeding and life expectancy in dogs: mongrels live longer than pure breeds.

This study aimed to investigate the establishment of relationship between inbreeding and life expectancy in dogs. A dataset of N = 30,563 dogs sourced from the VetCompass™ Program, UK was made available by the Royal Veterinary College, University of London, containing information about breed and longevity and was subject to survival analysis. A Cox regression proportional hazards model was used to differentiate survivability in three groups of dogs (mongrel, cross-bred and pure breed). The model was found highly significant (p < 0.001) and we found that mongrel dog had the highest life expectancy, followed by cross-bred dogs with only one purebred ancestor and purebred dogs had the lowest life expectancy. A second Cox regression was also found highly significant (p < 0.001) differentiating the lifespan of different dog breed and correlating positively the hazard ratio and the Genetic Illness Severity Index for Dogs (GISID). The results show that survivability is higher in mongrel dogs followed by cross-bred with one of the ancestor only as a pure breed, and pure breed dog have the highest morbidity level. Higher morbidity is associated with higher GISID scores, and therefore, higher inbreeding coefficients. These findings have important implications for dog breeders, owners, and animal welfare organizations seeking to promote healthier, longer-lived dogs.

European citizens' stance on limiting energy use for climate change mitigation.

Citizens' attitudes and beliefs towards climate change are decisive in the adoption of mitigating measures. Limiting the use of energy in the context of climate change can be one of the mitigation measures, and therefore, understanding the position of the citizens towards it is important. With this aim, we used data from the 10th European Social Survey to relate the European citizens' beliefs and attitudes on limiting the use of energy to tackle climate change. We have used variables related to demography and individuals' perception of society and its policies. Statistical models were successfully fitted to data. Individuals with higher levels of trust in scientists have a higher degree of satisfaction with the national economies, are more worried about climate change and are more capable of assuming self-responsibility in climate change mitigation. These individuals have higher probabilities of believing that climate change mitigation could be achieved by limiting the use of energy. The EU citizens are, however, very skeptical in relation to the probability of many other citizens adopting measures to limit the use of energy.

A meta-analysis of the mastitis vaccination efficacy in dairy cattle.

Background: Mastitis is the most important disease in dairy cattle with impact in welfare of animals and the economy of the dairy farming activity. Attempts have been made to produce vaccines to prevent the disease, however, results have been dubious. Aim: The aim of this study was to evaluate the efficacy of the mastitis vaccination in dairy cattle by merging several trials to allow evidence synthesis. Methods: A list of publications with common methodological grounds was selected to allow a quantitative comparison in a meta-analysis with moderators. Results: A mixed methods model (p < 0.001), with four significant moderators was successfully fitted: "year of publication" (p < 0.001), "vaccination timing" (p < 0.01), "type of animal" (p < 0.001), and "vaccine fabrication" (p < 0.001). The model is homogeneous (p > 0.05), with the moderators explaining the variability. Efficacy decreases over time. Vaccines applied after calving show inefficacy [log risk ratio (RR) 1.72 (1.34, 2.21)], and applied before calving show reduced efficacy [log RR 0.86 (0.72, 1.03)]. Commercial vaccines don't show efficacy [log RR 1.07 (0.94, 1.22)]. Self-fabricated vaccines show efficacy [log RR (0.51, 0.94)]. Conclusion: Full clarification of efficacy is not shown; however, if vaccination is used, must follow a pre-calving protocol. While not showing efficacy, the vaccination has demonstrated a reduction of the severity in clinical cases, rate of culling, and has increased the production of milk and milk solids. Vaccination may improve health and welfare but does not prevent the disease effectively; it must be seen as an additional tool to the traditional preventive measures.

Skin pigmentation as landmark for arteriovenous fistula cannulation in hemodialysis.

BACKGROUND: The cannulation of the arteriovenous fistula (AVF) for hemodialysis (HD) has traditionally depended on the nurse's tactile sensation, which has been associated with suboptimal needle placement and detrimental effects on vascular access (VA) longevity. While the introduction of ultrasound (US) has proven beneficial in mapping the AVF outflow vein and assisting in cannulation planning, aneurysmal deformations remain a common occurrence resulting from various factors, including inadequate cannulation techniques. Within this context, the utilization of skin pigmentation as a clinical landmark has emerged as a potential approach to enhance cannulation planning in HD. METHODS: A prospective longitudinal study was undertaken to investigate the correlation between the occurrence of venous morphological deformations and the cannulation technique guided by skin pigmentation after a 2-month period of implementation. RESULTS: Thirty patients were enrolled in the study with 433 cannulations being described within the first 2 months of AVF use. The overall rate of cannulation-related adverse events was 21.9%. Comparative analysis demonstrated a statistically significant relationship (p < 0.001) between aneurysmal deformation and non-compliance with the proposed cannulation technique, resulting in cannulation outside the designated points. Non-compliance was primarily attributed to nurse's decision (57.1%). CONCLUSION: The integration of US mapping of the AVF outflow vein and the utilization of skin pigmentation as a guiding tool have shown promising results in enhancing cannulation planning over time. Consistent adherence to a cannulation technique other than the area technique has been found to reduce the risk of AVF morphological deformation. These findings underscore the potential benefits of incorporating skin pigmentation as a clinical landmark in cannulation practices, highlighting its ability to impact positively cannulation outcomes.

Current Options in the Valorisation of Vine Pruning Residue for the Production of Biofuels, Biopolymers, Antioxidants, and Bio-Composites following the Concept of Biorefinery: A Review.

Europe is considered the largest producer of wine worldwide, showing a high market potential. Several wastes are generated at the different stages of the wine production process, namely, vine pruning, stalks, and grape marc. Typically, these residues are not used and are commonly discarded. Portugal generates annually approximately 178 thousand metric tons of wine production waste. In this context, the interest in redirecting the use of these residues has increased due to overproduction, great availability, and low costs. The utilization of these lignocellulosic biomasses derived from the wine industry would economically benefit the producers, while mitigating impacts on the environment. These by-products can be submitted to pre-treatments (physical, chemical, and biological) for the separation of different compounds with high industrial interest, reducing the waste of agro-industrial activities and increasing industrial profitability. Particularly, vine-pruning residue, besides being a source of sugar, has high nutritional value and may serve as a source of phenolic compounds. These compounds can be obtained by bioconversion, following a concept of biorefinery. In this framework, the current routes of the valorisation of the pruning residues will be addressed and put into a circular economy context.

Cross sectional epidemiological study of the severity of buccal ulceration and sharp enamel points in ridden and unridden horses.

The process of domestication of the horse introduced changes limiting accessibility to graze land and roughage while increasing highly digestible carbohydrates content of meal-fedrations. We have tested whether the effect of a higher degree of human contact impacts horses' welfare by assessing the development of sharp enamel points (SEP) and buccal ulcerations (BU) in ridden and unridden horses. We were able to fit logistic regression models significantly differentiating the impact of these two conditions in both groups of horses (p < 0.001 for SEP and p < 0.01 for BU). The impact is higher in ridden horses for both conditions. These two conditions were found to correlate positively (ρ = 0.63, p < 0.001). We argued that human contact may impact on horses' welfare. Further studies may help to clarify this impact with more detail. Dentistry may be helpful to provide improved welfare conditions; however, without regular access to grazed land, the stabled horses' welfare may be at stake.

Perceptions of Farm Animal Sentience and Suffering: Evidence from the BRIC Countries and the United States.

In this study, we examined how beliefs about farm animal sentience and their suffering vary across culture and demographic characteristics. A total of N = 5027) questionnaires were administered in Brazil, Russia, India, China, and the USA. Brazilians showed higher and Chinese lower levels of perceived animal sentience. In Russia and India, the perception of suffering and sentience increases with age, with similar levels to those observed in the USA. In all the countries, more people agreed than disagreed that animals are sentient. Men in India show higher levels of agreement with the relation between eating meat and animal suffering, followed by women in Brazil and China. Lower levels of agreement are observed in Americans and Chinese. Women show higher levels of compassion than men. In Russia, there is a slightly higher level of agreement between men and in the USA younger men agree more. Young American men show higher levels of agreement, while in India and China age has the opposite effect. For fair trading competition, it is important to standardize procedures and respect the demand for both animal protein and its ethical production. Overall, our results showed that perceptions of farm animal sentience and suffering vary substantially across countries and demographic groups. These differences could have important consequences for the perceived ethicality of meat production and consumption, and for global trade in animal products.

Effects of ß-Hydroxy ß-Methylbutyric Supplementation in Combination with Conservative Non-Invasive Treatments in Athletes with Patellar Tendinopathy: A Pilot Study.

The aim of the present study was to analyze the effect of conservative non-invasive treatments based on eccentric training, stretching and extracorporeal shock wave therapy (ESWT) supplemented with ß-Hydroxy ß-methylbutyric (HMB) or placebo (PLAC) on body composition, pain and muscular function (jump ability, muscular power and muscular strength) in athletes with patellar tendinopathy (PT). In a double-blind randomized trial, 8 athletes (4 males and 4 females) performed a physical rehabilitation for 4 weeks. They were randomly divided into two experimental groups (two males and two females in each one) that ingested HMB (HMBG) or PLAC (PLACG). In pre- and post-intervention were assessed body composition, pain, countermovement jump (CMJ), back-squat (BS) for analyzing peak power (W) (PPPP), load (kg) associated to PPPP (PPKG) and mean velocity (m/s) (PPMV) in addition to a 5-RM leg extension tests. An interaction intervention·supplementation (p = 0.049; È 2p = 0.774) was observed in the height reached in the CMJ as an intervention effect in PPPP detected for the HMBG (p = 0.049). In addition, an enhancement in PPKG (p = 0.028; È 2p = 0.842) was detected in the intervention, but not in PPMV, as an increase in the intervention in the 5-RM test (p = 0.001; È 2p = 0.981) was observed. No changes were noted on body composition or pain (p > 0.05). The combination of eccentric training with stretching and ESWT increased concentric muscular power and strength after 4 weeks without changes in body lean mass or pain. In addition, HMB supplementation could enhance the power muscular performance in athletes with PT, optimizing the intervention adaptions.

Achieving an Optimal Fat Loss Phase in Resistance-Trained Athletes: A Narrative Review.

Managing the body composition of athletes is a common practice in the field of sports nutrition. The loss of body weight (BW) in resistance-trained athletes is mainly conducted for aesthetic reasons (bodybuilding) or performance (powerlifting or weightlifting). The aim of this review is to provide dietary-nutritional strategies for the loss of fat mass in resistance-trained athletes. During the weight loss phase, the goal is to reduce the fat mass by maximizing the retention of fat-free mass. In this narrative review, the scientific literature is evaluated, and dietary-nutritional and supplementation recommendations for the weight loss phase of resistance-trained athletes are provided. Caloric intake should be set based on a target BW loss of 0.5-1.0%/week to maximize fat-free mass retention. Protein intake (2.2-3.0 g/kgBW/day) should be distributed throughout the day (3-6 meals), ensuring in each meal an adequate amount of protein (0.40-0.55 g/kgBW/meal) and including a meal within 2-3 h before and after training. Carbohydrate intake should be adapted to the level of activity of the athlete in order to training performance (2-5 g/kgBW/day). Caffeine (3-6 mg/kgBW/day) and creatine monohydrate (3-5 g/day) could be incorporated into the athlete's diet due to their ergogenic effects in relation to resistance training. The intake of micronutrients complexes should be limited to special situations in which there is a real deficiency, and the athlete cannot consume through their diet.

Morning versus Evening Intake of Creatine in Elite Female Handball Players.

A great deal of evidence has been gathered on the use of creatine as an ergogenic supplement. Recent studies show greater benefits when creatine ingestion is performed close in time to training, but few studies tackle the way that circadian rhythms could influence creatine consumption. The aim of this study was therefore to observe the influence circadian rhythms exert on sports performance after creatine supplementation. Our method involved randomly assigning fourteen women players of a handball team into two groups in a single-blind study: one that consumed the supplement in the morning and one that consumed it in the evening, with both groups following a specific training program. After twelve weeks, the participants exhibited a decreased fat percentage, increased body weight and body water, and improved performance, with these results being very similar in the two groups. It is therefore concluded that, although circadian rhythms may influence performance, these appear not to affect creatine supplementation, as creatine is stored intramuscularly and is available for those moments of high energy demand, regardless of the time of day.

Analysis of the consumption of sports supplements in elite fencers according to sex and competitive level.

BACKGROUND: The aim of this study was to analyze the consumption of sports supplements (SS) in competitive level fencers and compare differences based on sex and competitive level (international and national). METHODS: A total of 49 fencers (18 men and 31 women) of national (n = 16) and international (n = 33) level completed a questionnaire with questions about SS consumption and the possible repercussions on health and / or sports performance. The results were analyzed based on the different categorizations established by the Australian Institute of Sport (AIS), as well as by sex and level of competence to which the participants belonged to. RESULTS: 46.9% of fencers have consumed SS with the main motivation being performance improvement (34.2%). Medical doctors were the individuals who were more likely to advise men to consume SS (50.0% vs 5.6%; OR = 3.29 [1.50-7.20]). Friends were most likely to advise women (38.9% vs 8.3%; OR = 1.75 [1.05-2.93]). The most consumed SS were sport drinks (44.9%), vitamin C (43.4%), sport bars (38.8%), and caffeine (28.6%). In regards to the SS categories, it was observed differences in the interaction level·sex in medical supplements (p = 0.017). In addition, there was a higher prevalence of whey protein consumption in women (25.8% vs 0%; p = 0.020) and iron consumption in men (33% vs 6.5%; p = 0.039). CONCLUSIONS: The prevalence of SS use in fencers is within the values previously reported in athletes of the same competitive level. There were no differences by sex and competitive level in the total consumption of SS, nor in each of the groups of level of evidence, being sport drinks, bars and caffeine the most consumed SS.

[Fraud in nutritional supplements for athletes: a narrative review]. / Fraude en suplementos nutricionales para deportistas: revisión narrativa.

INTRODUCTION: The use of nutritional supplements (NSs) is a widespread practice in both professional and amateur athletes. Their choice must be based on criteria of safety, legality, and effectiveness. There are several risks that some of these products can trigger, this being a reason for fraud to the consumer. By way of example, the presence of a legal substance in doses higher than its recommendation may cause unwanted side effects; on the other hand, its presence in quantities lower than necessary (effective threshold) may not have the effect expected or announced by the product. Therefore, the objective of this review was to describe the existence of fraud in relation to nutritional labeling and/or to the content of NSs intended for athletes. A narrative review was conducted through PubMed in which 16 studies met the inclusion criteria. The results show that nutritional labeling differs from the actual amounts of ingredients. This type of fraud has been found in protein powder supplements, pre-workout mixtures, creatine, and beverages containing vitamins and minerals, among others. Fraud due to errors in the labeling by omission of substances present in the product or by errors in the analysis or declaration of quantities, is high. This lack of transparency in the actual composition of labels can contribute to sports performance and/or health problems in the athlete. Therefore, an improvement of the legislation on NS is necessary to ensure their safety, effectiveness, and legality.

INTRODUCCIÓN: El uso de suplementos nutricionales (SN) es una práctica muy extendida tanto entre los deportistas profesionales como entre los amateurs. Su elección debe realizarse basándose en criterios de seguridad, legalidad y eficacia. Son varios los riesgos que algunos de estos productos pueden desencadenar, siendo motivo de fraude para el consumidor. A modo de ejemplo, la presencia de una sustancia legal en dosis superiores a sus recomendaciones puede ocasionar efectos secundarios indeseados; por el contrario, su presencia en cantidades inferiores a las necesarias (umbral efectivo) puede no provocar el efecto esperado o anunciado por el producto. Por ello, el objetivo de la presente revisión es describir la existencia de fraude en relación con el etiquetado nutricional y/o el contenido de los SN destinados a deportistas. Se realizó una revisión narrativa a través de Pubmed en la que 16 estudios cumplieron los criterios de inclusión. Los resultados muestran que el etiquetado nutricional difiere de la cantidad real de ingredientes. Este tipo de fraude se ha encontrado en suplementos de proteína en polvo, mezclas preentrenamiento, creatina y bebidas que contienen vitaminas y minerales, entre otros. El fraude debido a errores en el etiquetado, por omisión de sustancias presentes en el producto o por errores en el análisis o declaración de las cantidades, es alto. Esta falta de transparencia en la composición real del etiquetado puede contribuir a problemas de rendimiento deportivo y/o de salud en el deportista. Por lo tanto, es necesaria una mejora de la legislación de los SN para garantizar su seguridad, eficacia y legalidad.

Does Beef Protein Supplementation Improve Body Composition and Exercise Performance? A Systematic Review and Meta-Analysis of Randomized Controlled Trials.

Protein supplementation might improve body composition and exercise performance. Supplements containing whey protein (WP) have received the most attention, but other protein sources such as beef protein (BP) are gaining popularity. We conducted a systematic review and meta-analysis of randomized controlled trials that compared the effects of exercise training combined with BP, WP or no protein supplementation (NP), on body composition or exercise performance. Secondary endpoints included intervention effects on total protein intake and hematological parameters. Seven studies (n = 270 participants) were included. No differences were found between BP and WP for total protein intake (standardized mean difference (SMD) = 0.04, p = 0.892), lean body mass (LBM) (SMD = -0.01, p = 0.970) or fat mass (SMD = 0.07, p = 0.760). BP significantly increased total daily protein intake (SMD = 0.68, p < 0.001), LBM (SMD = 0.34, p = 0.049) and lower-limb muscle strength (SMD = 0.40, p = 0.014) compared to NP, but no significant differences were found between both conditions for fat mass (SMD = 0.15, p = 0.256), upper-limb muscle strength (SMD = 0.16, p = 0.536) or total iron intake (SMD = 0.29, p = 0.089). In summary, BP provides similar effects to WP on protein intake and body composition and, compared to NP, might be an effective intervention to increase total daily protein intake, LBM and lower-limb muscle strength.

Carbohydrate Availability and Physical Performance: Physiological Overview and Practical Recommendations.

Strong evidence during the last few decades has highlighted the importance of nutrition for sport performance, the role of carbohydrates (CHO) being of special interest. Glycogen is currently not only considered an energy substrate but also a regulator of the signaling pathways that regulate exercise-induced adaptations. Thus, low or high CHO availabilities can result in both beneficial or negative results depending on the purpose. On the one hand, the depletion of glycogen levels is a limiting factor of performance during sessions in which high exercise intensities are required; therefore ensuring a high CHO availability before and during exercise is of major importance. A high CHO availability has also been positively related to the exercise-induced adaptations to resistance training. By contrast, a low CHO availability seems to promote endurance-exercise-induced adaptations such as mitochondrial biogenesis and enhanced lipolysis. In the present narrative review, we aim to provide a holistic overview of how CHO availability impacts physical performance as well as to provide practical recommendations on how training and nutrition might be combined to maximize performance. Attending to the existing evidence, no universal recommendations regarding CHO intake can be given to athletes as nutrition should be periodized according to training loads and objectives.