Relationship between Strength and Professional Quality of Life of Nurses Working Hospital Emergency Departments.

Optimal quality of professional life can allow coping with stressful situations and avoiding fatigue. This is instrumental in jobs undergoing very demanding situations, such as nurses working in Emergency Departments. In this study, we investigated the relationship between functional and physiological indicators and the quality of professional life in nurses of Emergency Departments of two public hospitals. Fifty-nine professionals participated in the study. Cortisol (an indicator of stress) and post-test lactate (an indicator of fatigue) were analyzed in saliva and in the blood, respectively, at the beginning and at the end of the morning shift. The CVP-35 survey (Spanish version of the QPL-35 questionnaire) was used to assess the quality of professional life. Post-dynamometry circulating lactate levels increased significantly; meanwhile, salivary cortisol decreased in participants at the end of the working shift. Regarding dynamometry, no significant changes were observed. CVP-35/QPL-35 scores did not show significant changes in participants from both hospitals in all dimensions analyzed. In conclusion, nurses participating in the study displayed adaptation to stress accompanied by an acceptable level of professional quality of life. However, certain fatigue appears at the end of the working day. Altogether, results suggest that a better organization must be implemented at work, improving ergonomic, safe, and healthy conditions.

Plantar Fasciitis in Soccer Players-A Systemic Review.

Soccer is one of the most popular sports in the world. Players often suffer a variety of injuries, the most common being injuries to muscles and tendons. It is striking that with soccer, being the most practiced sport, and considering that most injuries occur in the lower extremities, plantar fasciitis (PF) is not one of the most frequent injuries (at least in terms of clinical data collected). The purpose of this review was to provide a comprehensive update of the topic "plantar fasciitis" focusing on soccer players. The review was conducted in accordance with the PRISMA (Preferred Reportiog ltems for Systmiatic reviews and Meta-Analyses) statement. PubMed, Cochrane Library and Scopus were researched. PICO (Patient, Population or Problem; Intervention; Comparison; and Outcome) components were identified. The keywords used were "plantar fasciitis", "plantar fasciitis and sport", "plantar fasciitis risk factors", "plantar fasciitis soccer" and "plantar fasciitis football players". With respect to the objective proposed for the research, we found eight specific articles focused on soccer. Of these, five were general reviews discussing the different methods of treatment of this pathology, and we have only found three studies that focused on PF in soccer, with two of them referring to a clinical case whereby the report and discussion only dealt with the specific treatment followed by the soccer player. After reviewing the manuscripts included in this work, we were surprised that there is no data in which the Silfverskiöld test was performed, as this test explores the passive mobility of the ankle and the degree of dorsiflexion in the supine position. We concluded that soccer players suffer pain in the sole of the foot compatible with plantar fasciitis; however, as indicated by Suzue et al., it is often not diagnosed because the athlete does not consider performing the clinical examinations necessary for its diagnosis. The shortage of reported publications in soccer may mask other PF-associated injuries.

C1-C2 Rotatory Subluxation in Adults "A Narrative Review".

The atlantoaxial joint C2 (axis) with the anterior arch of C1 (atlas) allows 50% of cervical lateral rotation. It is responsible for precise and important movements that allow us to perform precise actions, both in normal and working life. Due to low incidence in adults, this condition often goes undiagnosed, or the diagnosis is delayed and the outcome is worse. An early diagnosis and treatment are essential to ensure satisfactory neurological and functional outcomes. The aim of this review is to analyze C1-C2 rotatory subluxation in adults, given its rarity. The time between injury and reduction is key, as it is directly related to prognosis and the severity of the treatment options. Due to low incidence in adults, this condition often goes undiagnosed, or the diagnosis is delayed as a lot of cases are not related to a clear trauma, with a poor prognosis just because of the late diagnosis and the outcome is worse. The correct approach and treatment of atlantoaxial dislocation requires a careful study of the radiological findings to decide the direction and plane of the dislocation, and the search for associated skeletal anomalies.

Professional Quality of Life of Healthcare Workers in Hospital Emergency Departments.

In previous publications, we have reported that professionals in emergency departments undergo high levels of stress according to the amounts of salivary biomarkers (α-amylase and cortisol). The stress seems to be counteracted by increased levels of dehydroepiandrosterone. This hypothesis is confirmed in the answers to different tests indicating no working stress, no anxiety, optimal self-efficacy, and good sleeping quality. Altogether, these previous results suggest an optimal adaptation of these workers to the demanding situations that occur in emergency departments. To complete this research, we decided to evaluate the quality of life of health professionals working in the emergency departments of two Spanish hospitals. A descriptive cross-sectional study was carried out during the pre-pandemic months of July and August 2019. We determined the professional quality of life through the QPL-35 questionnaire in 97 participants, including nurses (n = 59) and medical doctors (n = 38). Answers to the test indicate that the studied participants working in emergency departments have a good perception of professional quality of life. This is reflected in the three dimensions of the questionnaire: managerial support, workloads, and intrinsic motivation. Based on the results of all answered tests, emergency healthcare staff seem to have adequate professional management, with levels of stress, sleep, and quality of life in line with a controlled lifestyle. Altogether, this would allow a correct adaptation to the demanding situations experienced in emergency departments. The relevance to clinical practice is that the COVID-19 pandemic has disrupted this controlled professional management.

Muscle Recovery and Nutrition.

Recovery strategies, both in the general population and in athletes, must be aimed at the main causes of fatigue [...].

Effects and Causes of Detraining in Athletes Due to COVID-19: A Review.

Several aspects of systemic alterations caused by the SARS-CoV-2 virus and the resultant COVID-19 disease have been currently explored in the general population. However, very little is known about these particular aspects in sportsmen and sportswomen. We believe that the most important element to take into account is the neuromuscular aspect, due to the implications that this system entails in motion execution and coordination. In this context, deficient neuromuscular control when performing dynamic actions can be an important risk factor for injury. Therefore, data in this review refer mainly to problems derived in the short term from athletes who have suffered this pathology, taking into account that COVID-19 is a very new disease and the presented data are still not conclusive. The review addresses two key aspects: performance alteration and the return to regular professional physical activity. COVID-19 causes metabolic-respiratory, muscular, cardiac, and neurological alterations that are accompanied by a situation of stress. All of these have a clear influence on performance but at the same time in the strategy of returning to optimal conditions to train and compete again after infection. From the clinical evidence, the resumption of physical training and sports activity should be carried out progressively, both in terms of time and intensity.

Peripheral Neuropathies Derived from COVID-19: New Perspectives for Treatment.

Peripheral neuropathies constitute a group of disorders affecting the peripheral nervous system. Neuropathies have multiple causes such as infections (i.e., COVID-19), diabetes, and nutritional (low vitamin levels), among others. Many micronutrients, such as vitamins (A, C, D, E, B6, B12, and folate), certain minerals (Fe, Mg, Zn, Se, and Cu), and ω-3 fatty acids have immunomodulatory effects. Therefore, they may play an instrumental role in the treatment of COVID-19 infection. However, many COVID-19 patients can undergo neuropathy. In this context, there is a wealth of information on a variety of first-, second-, and third-line treatment options. This review focuses on the application of nutraceutical strategies in order to improve the symptomatology of neuropathy and neuropathic pain in patients that suffered from COVID-19. Our aim is to provide an alternative vision to traditional medical-pharmacological treatment through nutraceuticals.

Effects of Eccentric vs. Concentric Sports on Blood Muscular Damage Markers in Male Professional Players.

BACKGROUND: Repetitive eccentric contractions can lead to higher degree of damage compared to repetitive concentric contractions. However, this type of exercise does not reproduce the real situations during the season in competitive sport disciplines. METHODS: We analyzed the pattern of muscle damage blood markers in male professionals from three disciplines: cycling (n = 18), mainly concentric, vs. basketball (n = 12) and volleyball (n = 14), both mainly eccentric. Circulating muscle markers were analyzed in two moments of the regular season: after a 20-day training (no competition) period (T1) and after a 20-day period of high demanding competition (T2). RESULTS: Blood levels of creatine kinase and myoglobin (muscle markers) increased in all groups at T2 compared to T1 as a result of competition intensity. The lower increases were noticed in cyclists at the end of both periods. Testosterone levels decreased at T2 compared to T1 in all disciplines, with lower levels found in cyclists. However, cortisol plasma levels decreased in basketball and volleyball players at T2, but increased significantly in cyclists, suggesting a limited adaptation to the effort. CONCLUSIONS: The pattern of circulating muscle markers is different depending of the demanding efforts (training vs. competition) of each particular discipline.

l-Arginine and Beetroot Extract Supplementation in the Prevention of Sarcopenia.

Aging is associated with a significant decline in neuromuscular function, leading to a reduction in muscle mass and strength. The aim of the present report was to evaluate the effect of supplementation with nitric oxide precursors (l-arginine and beetroot extract) in muscular function during a training period of 6 weeks in elderly men and women. The study (double-blind, placebo-controlled) involved 66 subjects randomly divided into three groups: placebo, arginine-supplemented and beetroot extract-supplemented. At the end of this period, no changes in anthropometric parameters were observed. Regarding other circulating parameters, urea levels were significantly (p < 0.05) lower in women of the beetroot-supplemented group (31.6 ± 5.9 mg/dL) compared to placebo (41.3 ± 8.5 mg/dL) after 6 weeks of training. In addition, the circulating creatine kinase activity, as an index of muscle functionality, was significantly (p < 0.05) higher in women of the arginine- (214.1 ± 162.2 mIU/L) compared to the beetroot-supplemented group (84.4 ± 36.8 mIU/L) at the end of intervention. No significant effects were noticed with l-arginine or beetroot extract supplementation regarding strength, endurance and SPPB index. Only beetroot extract supplementation improved physical fitness significantly (p < 0.05) in the sprint exercise in men after 6 weeks (2.33 ± 0.59 s) compared to the baseline (2.72 ± 0.41 s). In conclusion, beetroot seems to be more efficient during short-term training while supplementing, preserving muscle functionality in women (decreased levels of circulating creatine kinase) and with modest effects in men.

The Immunomodulatory Function of Vitamin D, with Particular Reference to SARS-CoV-2.

Vaccines are the only way to reduce the morbidity associated to SARS-CoV-2 infection. The appearance of new mutations urges us to increase the effectiveness of vaccines as a complementary alternative. In this context, the use of adjuvant strategies has improved the effectiveness of different vaccines against virus infections such as dengue, influenza, and common cold. Recent reports on patients infected by COVID-19 reveal that low levels of circulating vitamin D correlate with a severe respiratory insufficiency. The immunomodulatory activity of this micronutrient attenuates the synthesis of pro-inflammatory cytokines and at the same time, increases antibody production. Therefore, the present review proposes the use of vitamin D as adjuvant micronutrient to increase the efficacy of vaccines against SARS-CoV-2 infection.

ß-Glucans Could Be Adjuvants for SARS-CoV-2 Virus Vaccines (COVID-19).

Waiting for an effective treatment against the SARS-CoV-2 virus (the cause of COVID-19), the current alternatives include prevention and the use of vaccines. At the moment, vaccination is the most effective strategy in the fight against pandemic. Vaccines can be administered with different natural biological products (adjuvants) with immunomodulating properties. Adjuvants can be taken orally, complementing vaccine action. Adjuvant compounds could play a key role in alleviating the symptoms of the disease, as well as in enhancing vaccine action. Adjuvants also contribute to an effective immune response and can enhance the protective effect of vaccines in immunocompromised individuals such as the elderly. Adjuvants must not produce adverse effects, toxicity, or any other symptoms that could alter immune system function. Vaccine adjuvants are substances of wide varying chemical structure that are used to boost the immune response against a simultaneously administered antigen. Glucans could work as adjuvants due to their immunomodulatory biological activity. In this respect, ß-(1,3)-(1,6) glucans are considered the most effective and safe according to the list issued by the European Commission. Only glucans with a ß-(1,3) bond linked to a ß-(1,6) are considered modulators of certain biological responses. The aim of this review is to present the possible effects of ß-glucans as adjuvants in the efficacy of vaccines against SARS-CoV-2 virus.

Effects of Vitamin D in Post-Exercise Muscle Recovery. A Systematic Review and Meta-Analysis.

Vitamin D is a key micronutrient modulating function and health in skeletal muscle. Therefore, we sought to systematically review the role of vitamin D in muscle recovery. A search in different databases (PubMed/MEDLINE, WOS, Google Scholar, and Scopus) was carried out following PRISMA® and PICOS. The search period was from inception to April 2020. Changes in post-exercise muscle damage were quantified comparing experimental group vs. placebo in each study by using number of participants, standardized mean difference (SMD), and standard error of the SMD. Hedges's g was used to calculate the SMDs for each study group and biased by the inverse of variance that allows calculating an overall effect and the 95% confidence interval (CI). The net vitamin D supplementation effect was calculated by subtracting the placebo SMD from SMD of the experimental group. The DerSimonian and Laird method was used as a random effect model, taking into account that the effect of vitamin D on muscular damage may vary according to the dose administered and additional moderators. Six studies were selected. In conclusion, regarding circulating levels of muscle biomarkers and additional limitations of the studies, it cannot be concluded that vitamin D supplementation exerts an effect in post-exercise muscle recovery. Likely, the anti-inflammatory action of vitamin D is quicker than the recovery of tissue structure and function. This aspect is pending verification in future research.

L-Citrulline Supplementation and Exercise in the Management of Sarcopenia.

Sarcopenia is a process associated to aging. Persistent inflammation and oxidative stress in muscle favour muscle wasting and decreased ability to perform physical activity. Controlled exercise can optimize blood flux and moderate the production of reactive oxygen species. Therefore, supplements that can work as a vasodilators and control oxidative stress, might be beneficial for active elders. In this context, we have tested citrulline supplementation in a group of 44 participants aged from 60-73 years that followed a physical activity program adapted to their age and capacities. Volunteers were divided in two groups: placebo (n = 22) and citrullline supplemented (n = 22). Different physical tests and blood extractions were performed at the beginning and at the end of intervention (six weeks). Strength and endurance showed a tendency to increase in the citrulline supplemented group, with no significant differences respect to placebo. However, walking speed in the citrulline supplemented group improved significantly compared to placebo. Markers of muscle damage as well as circulating levels of testosterone, cortisol and vitamin D showed no significant changes, but a tendency to improve at the end of intervention in the supplemented group compared to placebo. Additional studies are necessary to confirm the effect of citrulline supplementation in sarcopenia delay.

Vitamin D, Its Role in Recovery after Muscular Damage Following Exercise.

Aside from its role in bone metabolism, vitamin D is a key immunomodulatory micronutrient. The active form of vitamin D (1,25(OH)D) seems to modulate the innate immune system through different mechanisms. The vitamin is involved in the differentiation of monocytes into macrophages, increasing the phagocytic and chemotactic functions of these cells. At the same time, vitamin D enables efferocytosis and prevents immunopathology. In addition, vitamin D is involved in other processes related to immune function, such as inflammation. Regarding muscle tissue, vitamin D plays an active role in muscle inflammatory response, protein synthesis, and regulation of skeletal muscle function. Two mechanisms have been proposed: A direct role of 1,25(OH)D binding to vitamin D receptors (VDRs) in muscle cells and the modulation of calcium transport in the sarcoplasmic reticulum. This second mechanism needs additional investigation. In conclusion, vitamin D seems to be effective in cases of deficiency and/or if there is a great muscular commitment, such as in high intensity exercises.

Effect of Glutamine Supplementation on Muscular Damage Biomarkers in Professional Basketball Players.

Scientific evidence supports the role of L-glutamine in improving immune function. This could suggest a possible role of L-glutamine in recovery after intense exercise. To this end, the present report aimed to study if oral L-glutamine supplementation could attenuate muscle damage in a group of players of a mainly eccentric sport discipline such as basketball. Participants (n = 12) were supplemented with 6 g/day of glutamine (G group) or placebo (P group) for 40 days in a crossover study design (20 days with glutamine + 20 days with placebo and vice versa). Blood samples were obtained at the beginning and at the end of each period and markers from exercise-induced muscle damage were determined. The glutamine supplemented group displayed significantly low values of aspartate transaminase, creatine kinase and myoglobin in blood, suggesting less muscle damage compared to the placebo. In addition, adrenocorticotropic hormone levels were lower in the glutamine supplemented group than in the placebo. As a result, the circulating cortisol levels did not increase at the end of the study in the glutamine supplemented group. Altogether, the results indicate that glutamine could help attenuate exercise-induced muscle damage in sport disciplines with predominantly eccentric actions.

Sarcopenia: Molecular Pathways and Potential Targets for Intervention.

Aging is associated with sarcopenia. The loss of strength results in decreased muscle mass and motor function. This process accelerates the progressive muscle deterioration observed in older adults, favoring the presence of debilitating pathologies. In addition, sarcopenia leads to a decrease in quality of life, significantly affecting self-sufficiency. Altogether, these results in an increase in economic resources from the National Health Systems devoted to mitigating this problem in the elderly, particularly in developed countries. Different etiological determinants are involved in the progression of the disease, including: neurological factors, endocrine alterations, as well as nutritional and lifestyle changes related to the adoption of more sedentary habits. Molecular and cellular mechanisms have not been clearly characterized, resulting in the absence of an effective treatment for sarcopenia. Nevertheless, physical activity seems to be the sole strategy to delay sarcopenia and its symptoms. The present review intends to bring together the data explaining how physical activity modulates at a molecular and cellular level all factors that predispose or favor the progression of this deteriorating pathology.

Ejercicio físico intradialítico en la enfermedad renal crónica: Revisión sistemática sobre los resultados de salud / Intradialytic physical exercise in chronic kidney disease: a systematic review of health outcomes

INTRODUCCIÓN: La enfermedad renal crónica (ERC) es un término general para los trastornos heterogéneos que afectan la estructura y la función del riñón. Las complicaciones de la ERC limitan considerablemente la tolerancia al ejercicio físico (EFi) al reducir la capacidad funcional, la resistencia y la fuerza. Sin embargo, la práctica de EFi regular contribuye a retrasar la progresión de la ERC y, estimular mejoras en la calidad de vida relacionada con la salud (CVRS). EFi realizado en período de hemodiálisis podría ser la mejor opción al estimular la adherencia y estar bajo la supervisión médica. El propósito del trabajo es examinar la efectividad de EFi intradialítico (iHD) sobre los resultados de salud en pacientes con ERC identificando el com-ponente del EFi más adecuado. MATERIAL Y MÉTODO: Revisión sistemática, basada en las guías PRISMA, realizando una búsqueda estructurada en las bases Medline, SciELO y Cochrane Library Plus. Se incluyeron publicaciones de los últimos 5 años que relacionaran el EFi iHD y la ERC hasta el 31 de diciembre de 2019. La calidad metodológica de los artículos se evaluó mediante el formulario de revisión crítica de McMaster. RESULTADOS: Se encontraron 7 artículos que han descrito incrementos de la resistencia aeróbica, la fuerza muscular de los miembros superiores e inferiores, y sobre la CVRS de los pacientes de ERC proporcionando mejoras emocionales, sociales y psicológicas. Además, el EFi iHD es capaz de controlar el estrés oxidativo, la inflamación, mejorar el perfil lipídico y estimular las células progenitoras endoteliales, lo que conjuntamente permite reducir los riegos de mortalidad asociada a las múltiples comorbilidades de los pacientes ERC, especialmente las cardiovasculares. CONCLUSIONES: EFi proporciona mejoras de la función y la capacidad física, la CVRS y los marcadores biológicos. Se emplean programas de EFi aeróbico, de fuerza muscular y EFi combinado de ambos

INTRODUCTION: Chronic kidney disease (CKD) is a general term for heterogeneous disorders that affect the structure and function of the kidney. Complications of CKD significantly limit exercise (Ex) tolerance by reducing functional capacity, endurance, and strength. However, the practice of regular Ex contributes to delaying the progression of CKD and stimulating improvements in health-related quality of life (HRQOL). Ex performed during the period of hemodialysis may be the best option when stimulating adherence and being under medical supervision. The purpose of the paper is to examine the effectiveness of intradialytic (iHD) Ex on health outcomes in patients with CKD by identifying the most appropriate component of Ex. MATERIAL AND METHOD: Systematic review, based on PRISMA guidelines, performing a structured search in Medline, SciELO and Cochrane Library Plus databases. Publications from the last 5 years relating iHD Ex and CKD up to 31 December 2019 were included. The methodological quality of the articles was evaluated using the McMaster critical review form. RESULTS: We found 7 articles that described increases in endurance, upper and lower limb muscle strength, and HRQL of CKD patients providing emotional, social and psychological improvements. In addition, iHD Ex is able to control oxidative stress, inflammation, improve the lipid profile and stimulate endothelial progenitor cells, which together reduce the risk of mortality associated with multiple comorbidities in CKD patients, especially cardiovascular ones. CONCLUSIONS: Ex provides improvements in physical function and capacity, HRQL and biological markers. Aerobic Ex, muscle strength Ex and combined Ex programs are used

Actividad física en pacientes oncológicos de cáncer de mama: ¿Terapia médica deportiva no farmacológica? Revisión sistemática / Physical activity in oncological breast cancer patients: non-pharmacological sports medical therapy? Systematic review

INTRODUCCIÓN: El cáncer de mama (CM) sigue siendo la causa principal de cáncer en las mujeres con casi 1,4 millones de casos nuevos en todo el mundo anualmente y 27.000 en España. Las terapias oncológicas, cada vez más eficaces, sin embargo, tienen numerosos efectos adversos como el degaste muscular, la fatiga, la disminución de la función física y la capacidad aeróbica, conjuntamente con el deterioro de la calidad de vida. En este sentido la actividad física (AF) parece ser una estrategia no farmacológica interesante para aliviar estas graves complicaciones y con potenciales beneficios para mujeres con CM. OBJETIVO: Examinar si las intervenciones de AF son efectivas sobre estado físico y psicológico de los pacientes de CM postquirúrgicos en estadíos tempranos de enfermedad (I-III) y además identificar el componente de la AF más adecuado. MATERIAL Y MÉTODO: Revisión sistemática, basada en las guías PRISMA, realizando una búsqueda estructurada en las bases de datos electrónicas: Medline (PubMed), SciELO y Cochrane Library Plus. Se incluyeron los resultados que relacionaran las AF y CM hasta el 30 de septiembre de 2019, mientras que se aplicó una restricción de búsqueda en las publicaciones para que fueran en los últimos 10 años. La calidad metodológica de los artículos se evaluó mediante el formulario de revisión crítica de McMaster. RESULTADOS: Se encontraron 8 artículos que han descrito los beneficios de la AF en los que destacan las mejoras físicas, psicológicas y en la calidad de vida, así como la disminución de la fatiga y linfedema. Las rutinas de ejercicio empleadas son de trabajo de componente aeróbico y de fuerza muscular. CONCLUSIÓN: La realización de AF, con rutinas de aeróbicas y de fuerza muscular, estimulan la mejora del estado físico, psico-lógico y la calidad de vida de los pacientes de CM

INTRODUCTION: Breast cancer (BC) remains the leading cause of cancer in women with nearly 1.4 million new cases worldwide annually and 27.000 in Spain. Increasingly effective oncology therapies, however, have numerous adverse effects such as muscle degeneration, fatigue, decreased physical function and aerobic capacity, along with deteriorating quality of life. In this sense physical activity (PA) seems to be an interesting non-pharmacological strategy to alleviate these serious complications and with potential benefits for women with BC. OBJECTIVE: To examine whether PA interventions are effective on the physical and psychological fitness of patients with post-surgical BC in early stages of disease (I-III) and also to identify the most appropriate component of physical activity. METHODS: Systematic review, based on PRISMA guidelines, using a structured search of electronic databases: Medline (Pub-Med), SciELO and Cochrane Library Plus. Results relating PA and BC were included until 30 september 2019, while a search restriction was applied to publications to be in the last 10 years. The methodological quality of articles evaluated using the McMaster critical review form. RESULTS: We found 8 articles that have described the benefits of PA, highlighting physical, psychological and quality of life improvements, as well as decreased fatigue and lymphedema. The exercise routines used are aerobic component work and muscle strength. CONCLUSION: The performance of AF, with aerobic and muscular strength routines, stimulate the improvement of the physical, psychological state and the quality of life of the patients of BC patients

Iron and Physical Activity: Bioavailability Enhancers, Properties of Black Pepper (Bioperine®) and Potential Applications.

Black pepper (Piper nigrum L.) has been employed in medicine (epilepsy, headaches, and diabetes), where its effects are mainly attributed to a nitrogen alkaloid called piperidine (1-(1-[1,3-benzodioxol-5-yl]-1-oxo-2,4 pentenyl) piperidine). Piperine co-administered with vitamins and minerals has improved its absorption. Therefore, this study aimed to describe the impact of the joint administration of iron (Fe) plus black pepper in physically active healthy individuals. Fe is a micronutrient that aids athletic performance by influencing the physiological functions involved in endurance sports by improving the transport, storage, and utilization of oxygen. Consequently, athletes have risk factors for Fe depletion, Fe deficiency, and eventually, anemia, mainly from mechanical hemolysis, gastrointestinal disturbances, and loss of Fe through excessive sweating. Declines in Fe stores have been reported to negatively alter physical capacities such as aerobic capacity, strength, and skeletal muscle recovery in elite athletes. Thus, there is a need to maintain Fe storage, even if Fe intake meets the recommended daily allowance (RDA), and Fe supplementation may be justified in physically active individuals, in states of Fe deficiency, with or without anemia. Females, in particular, should monitor their Fe hematological profile. The recommended oral Fe supplements are ferrous or ferric salts, sulfate, fumarate, and gluconate. These preparations constitute the first line of treatment; however, the high doses administered have gastrointestinal side effects that reduce tolerance and adherence to treatment. Thus, a strategy to counteract these adverse effects is to improve the bioavailability of Fe. Therefore, piperine may benefit the absorption of Fe through its bioavailability enhancement properties. Three research studies of Fe associated with black pepper have reported improvements in parameters related to the metabolism of Fe, without adverse effects. Although more research is needed, this could represent an advance in oral Fe supplementation for physically active individuals.

The Role of Selenium Mineral Trace Element in Exercise: Antioxidant Defense System, Muscle Performance, Hormone Response, and Athletic Performance. A Systematic Review.

Exercise overproduces oxygen reactive species (ROS) and eventually exceeds the body's antioxidant capacity to neutralize them. The ROS produce damaging effects on the cell membrane and contribute to skeletal muscle damage. Selenium (Se), a natural mineral trace element, is an essential component of selenoproteins that plays an important role in antioxidant defense. The activity of the enzyme glutathione peroxidase (GPx), a highly-efficient antioxidant enzyme, is closely dependent on the presence of Se. These properties of Se may be potentially applicable to improve athletic performance and training recovery. We systematically searched for published studies to evaluate the effectiveness of Se supplementation on antioxidant defense system, muscle performance, hormone response, and athletic performance among physically active individuals. We used the Preferred Reporting Elements for Systematic Reviews and Meta-Analysis (PRISMA) guidelines and searched in SCOPUS, Web of Science (WOS), and PubMed databases to identify published studies until March 2020. The systematic review incorporated original studies with randomized controlled crossover or parallel design in which intake of Se administered once a day was compared with the same placebo conditions. No exclusions were applied for the type of physical exercise performed, the sex, nor the age of the participants. Among 150 articles identified in the search, 6 met the criteria and were included in the systematic review. The methodological quality of the studies was evaluated using the McMaster Critical Review Form. Oral Se supplementation with 180 µg/day or 240 µg/day (selenomethionine) and 200 µg/day (Sodium Selenite), significantly decreased lipid hydroperoxide levels and increased GPx in plasma, erythrocyte, and muscle. No significant effects were observed on athletic performance, testosterone hormone levels, creatine kinase activity, and exercise training-induced adaptations on oxidative enzyme activities or on muscle fiber type myosin heavy chain expression. In addition, Se supplementation showed to have a dampening effect on the mitochondria changes in chronic and acute exercise. In summary, the use of Se supplementation has no benefits on aerobic or anaerobic athletic performance but it may prevent Se deficiencies among athletes with high-intensity and high-volume training. Optimal Se plasma levels may be important to minimize chronic exercise-induced oxidative effects and modulate the exercise effect on mitochondrial changes.