Is There a Relative Age Effect among the Most Successful Track and Field Athletes?

The prevalence of the Relative Age Effect (RAE) was studied among medalists from the World Athletics Championships at U18, U20 and Senior age groups and from the Olympic Games from 2000 to 2022. The specific events examined were the 100, 200, 400, 800, 1500, and 3000/5000 m, the long jump, the triple jump, the high jump and the pole vault. Dates of birth from 1,858 outdoor track and field athletes were analysed and further divided into four groups according to the quartile of birth. The RAE was found to be widespread among athletes of both sexes in U18 and U20 age groups in all examined disciplines. There was no difference between the most successful U18 and U20 athletes (p = 0.52). Among senior athletes of both sexes, this effect was not detected and the number of "late-born" athletes in this age group was higher than athletes born in the first three quarters. The prevalence of the RAE across the four groups of events was found in U18 and U20 age groups. Additionally, within each age group, the difference among events was statistically significant. In most successful track and field athletes, the RAE is only significant in U18 and U20 age groups. In senior athletes, the number of "late-born" athletes is significant while RAE disappears. These data may be considered when assessing the athletic potential of an individual athlete.

The effects of anti-doping measures on sports performance in weightlifting.

BACKGROUND: Evaluating anti-doping measures is essential to optimise their effectiveness. Comparing sporting results that have a higher doping prevalence, such as weightlifting, before and after the implementation of anti-doping measures may serve as an effectiveness indicator. METHODS: The results of the most successful weightlifters of both sexes in two time periods, 2009-2015 and 2016-2022 were analysed. The Sinclair Total (ST) to compare the relative strength of weightlifters from different weight categories was calculated. RESULTS: A significant decrease in the ST during 2016-2022 (p < 0.001) in athletes of all ages and both sexes overall was reported. When analysed by age, there was a decrease in ST in juniors and seniors of both sexes (p = 0.010 and p < 0.001, respectively), but not in youth. There was a decrease in the ST in senior men (p < 0.001), junior women (p < 0.001) and senior women (p < 0.001). CONCLUSION: In elite weightlifting, adult athletic results declined during 2016-2022, which may partly be explained by the implementation of new methods to detect long-term anabolic androgenic steroid metabolites as well as other policies. This may highlight the effectiveness of these methods both in the prevention and detection of anti-doping rule violations.

Comparative Analysis of Stromal Vascular Fraction and Alternative Mechanisms in Bone Fracture Stimulation to Bridge the Gap between Nature and Technological Advancement: A Systematic Review.

BACKGROUND: Various stimulation methods, including electrical, ultrasound, mechanical, and biological interventions, are explored, each leveraging intricate cellular and molecular dynamics to expedite healing. The advent of stromal vascular fraction (SVF) marks a significant stride, offering multifarious benefits in bone healing, from enhanced bone formation to optimal vascular integration, drawing a harmonious balance between innate mechanisms and scientific advancements. METHODS: This systematic review was conducted focusing on literature from 2016 to 2023 and encompassing various bone healing stimulation mechanisms like SVF, electrical, ultrasound, and mechanical stimulation. The extracted data underwent meticulous synthesis and analysis, emphasizing comparative evaluations of mechanisms, applications, and outcomes of each intervention. RESULTS: The reviewed studies reveal the potential of SVF in bone fracture healing, with its regenerative and anti-inflammatory effects. The purification of SVF is crucial for safe therapeutic use. Characterization involves flow cytometry and microscopy. Studies show SVF's efficacy in bone regeneration, versatility in various contexts, and potential for clinical use. SVF appears superior to electrical, ultrasound, and mechanical stimulation, with low complications. CONCLUSIONS: This review compares bone healing methods, including SVF. It provides valuable insights into SVF's potential for bone regeneration. However, due to limited human studies and potential bias, cautious interpretation is necessary. Further research is essential to validate these findings and determine the optimal SVF applications in bone healing.

Stromal Vascular Fraction Therapy for Knee Osteoarthritis: A Systematic Review.

Background and Objectives: Knee osteoarthritis (OA) is a widespread joint disease, set to increase due to aging and rising obesity. Beyond cartilage degeneration, OA involves the entire joint, including the synovial fluid, bones, and surrounding muscles. Existing treatments, such as NSAIDs and corticosteroid injections, mainly alleviate symptoms but can have complications. Joint replacement surgeries are definitive but carry surgical risks and are not suitable for all. Stromal vascular fraction (SVF) therapy is a regenerative approach using cells from a patient's adipose tissue. SVF addresses as degenerative and inflammatory aspects, with potential for cartilage formation and tissue regeneration. Unlike traditional treatments, SVF may reverse OA changes. Being autologous, it reduces immunogenic risks. Materials and Methods: A systematic search was undertaken across PubMed, Medline, and Scopus for relevant studies published from 2017 to 2023. Keywords included "SVF", "Knee Osteoarthritis", and "Regenerative Medicine". Results: This systematic search yielded a total of 172 articles. After the removal of duplicates and an initial title and abstract screening, 94 full-text articles were assessed for eligibility. Of these, 22 studies met the inclusion criteria and were subsequently included in this review. Conclusions: This review of SVF therapy for knee OA suggests its potential therapeutic benefits. Most studies confirmed its safety and efficacy, and showed improved clinical outcomes and minimal adverse events. However, differences in study designs and sizes require a careful interpretation of the results. While evidence supports SVF's positive effects, understanding methodological limitations is key. Incorporating SVF is promising, but the approach should prioritize patient safety and rigorous research.

A Comparative Analysis Between Conservative Treatment, Arthroscopic Repair, and Biceps Tenodesis in Superior Labral Anterior-Posterior (SLAP) Lesions.

Background "Throwing shoulder" hinders athletes' shoulder functions, causing pain, weakness, and performance reduction due to anatomical, physiological, and biomechanical factors. Anatomical issues include superior labral anterior-posterior (SLAP) injuries, rotator cuff injuries, and glenohumeral instability. Methods This study compared arthroscopic labral repairs in patients under 40 years old with shoulder injuries between 2015 and 2017. Sixty eligible patients were divided into three groups: conservative treatment, arthroscopic repair, and tenodesis. Measures included pain, functional scores, and the range of motion pre-/post-operation. Results At the last follow-up, pain relief and functional improvement were most significant with tenodesis (97% pain relief, 95% functional improvement), followed by repair (85% pain relief, 70% functional improvement), and least in conservative treatment (45% pain relief, 40% functional improvement). While all treatments significantly reduced pain and improved function (p<0.001), tenodesis demonstrated the highest effectiveness, suggesting it as a potentially preferred method. Significant improvements in pain relief and function were observed across all methods; however, surgical options suggested improved outcomes. Conclusion Our study compares conservative treatment, arthroscopic labral repair, and biceps tenodesis (BT) for SLAP lesions, highlighting significant pain relief and functional improvement across all. Conservative treatment suits patients with milder symptoms, while arthroscopic repair addresses larger tears. As the effectiveness of arthroscopic treatment is not inferior to conservative one, BT excels in cases of substantial bicep involvement.

Are Late-Born Young Soccer Players Less Mature Than Their Early-Born Peers, Although No Differences in Physical and Technical Performance Are Evident?

The aim of the study was to compare the status of somatic maturity, anthropometry, strength, speed, and soccer-specific technical skills of players from leading youth soccer academies born in different quarters of the same calendar year. A total of 678 young male soccer players from eight leading Russian soccer academies took part in the study. The following anthropometric measures and physical characteristics were measured: height, weight, body mass index, countermovement jumps (CMJ), 5, 10, and 20 m sprints, speed dribbling, foot and body ball juggling, and short and long pass accuracy. The determination of somatic maturity as a percentage of projected adult height was collected. All subject dates of birth were divided into four quartiles according to the month of birth. The analysis of all data obtained was conducted both within the total sample and by quartiles of birth, according to the age group categories of 12-13 years, 14-15 years, and 16-17 years and the degree of somatic maturity. There was a widespread relative age effect, with 43.5% of early-born players and only 9.6% of late-born players representing the sample. Early-born players were more mature than late-born players (p < 0.001 and p < 0.001) but had no statistically significant differences in strength, speed, or soccer-specific skills.

The relationship of testosterone levels with sprint performance in young professional track and field athletes.

Evidence suggests that higher testosterone levels may provide an athletic advantage. Therefore, it is of practical interest to examine the association between testosterone levels and power- and strength-related traits in young professional track and field athletes, and to consider the factors that determine testosterone levels. The study involved 68 young professional athletes (45 females, 17.3 ± 2.6 years; 23 males, 18.2 ± 1.9 years). Testosterone levels were assessed via liquid chromatography-mass spectrometry. All subjects performed two 20 m and two 30 m sprint trials, and countermovement jump without arm-swing. A bioimpedance analysis of body composition was carried out and biological maturity was examined using the Khamis-Roche method. The average testosterone levels were 26.4 ± 9.6 nmol/l and 1.5 ± 0.7 nmol/l in males and females, respectively. In female athletes, testosterone levels did not correlate with any of traits. Males with the highest testosterone levels were significantly faster in the 20 m (p = 0.033) and 30 m (p = 0.014) sprint trials compared to males with lower testosterone levels. Testosterone levels in males were positively associated with fat mass (p = 0.027), and degree of biological maturation (p = 0.003). In conclusion, we found a positive relationship between testosterone levels and sprint performance in young male athletes.

The relationship between ambient temperature and match running performance of elite soccer players.

The influence of environmental factors on key physical parameters of soccer players during competitive match-play have been widely investigated in the literature, although little is known on the effects of sub-zero ambient temperatures on the performance of adult elite soccer players during competitive matches. The aim of this study was to assess how the teams' match running performance indicators are related to low ambient temperature during competitive matches in the Russian Premier League. A total of 1142 matches played during the 2016/2017 to 2020/2021 seasons were examined. Linear mixed models were used to assess the relationships between changes in ambient temperature at the start of the match and changes in selected team physical performance variables, including total, running (4.0 to 5.5 m/s), high-speed running (5.5 to 7.0 m/s) and sprint (> 7.0 m/s) distances covered. The total, running and high-speed running distances showed no significant differences across temperatures up to 10°C, while these showed small to large decreases at 11 to 20°C and especially in the >20°C ranges. On the contrary, sprint distance was significantly lower at temperature of -5°C or less compared to higher temperature ranges. At sub-zero temperatures, every 1°C lower reduced team sprint distance by 19.2 m (about 1.6%). The present findings show that a low ambient temperature is negatively related to physical match performance behavior of elite soccer players, notably associated with a reduced total sprint distance.

Effect of xenon and argon inhalation on erythropoiesis and steroidogenesis: A systematic review.

Background: Xenon and argon inhalation were included on the WADA Prohibited List in 2014 due to the reported positive effects on erythropoiesis and steroidogenesis that occur as a result of their application. Thus, the systematic review of studies supporting these notions is of interest. Methods: A thorough search on the effects of xenon and argon inhalation on erythropoiesis and steroidogenesis, as well as their negative effects on human health and method detection was conducted. Pubmed and Google Scholar databases and the Cochrane Library were researched, as well as the WADA research section. The search was conducted in accordance with the PRISMA guidelines. All articles written in English and published between 2000 and 2021 were analyzed, as well as reference studies meeting the search criteria. Results: At present, there are only two publications in healthy human subjects evaluating the effects of xenon inhalation on erythropoiesis that found no conclusive evidence of a positive effect on erythropoiesis. This research was published following the inclusion of this gas on the WADA Prohibited List in 2014 and had a high risk of bias. There were no studies available on the effect of argon inhalation on erythropoiesis. Furthermore, no studies were found on the effect of xenon or argon inhalation on steroidogenesis in healthy subjects and no studies relating to the effects of xenon or argon inhalation on erythropoiesis and steroidogenesis were found on the WADA website. Conclusion: There is still inconclusive evidence to support the administration of xenon and argon inhalations on erythropoiesis and steroidogenesis and their positive effects on health. Further research is warranted to establish the effects of these gases. Additionally, improved communication between anti-doping authorities and all key stakeholders is required to support the inclusion of various substances on recognized prohibited lists.

Effects of new anti-doping measures on sports performance in elite female athletes.

Studies examining the effects of new anti-doping measures on sports performance in elite athletes are scarce. During the last decade, a number of new anti-doping methods for the detection of anabolic androgenic steroids were developed. We hypothesized that the implementation of these methods may cause a decrease of performance in athletic disciplines where given substances are widely used. For this purpose, the performance results for 10 athletic disciplines from country (Country A), which was widely accused of systematic doping use, were gathered and pooled into the 2012-2015 and 2016-2019 periods. These periods were seen as before and following the implementation periods, where the effects of new anti-doping methods could be manifested. Also, the performance results of their rival athletes from Country B were analyzed for comparison. The incidence of anti-doping rule violations for both countries was followed. The analysis revealed a decrease in performance results of Country A athletes in eight of 10 disciplines. The performance results of Country B's athletes in seven of 10 disciplines did not and in three disciplines did demonstrate statistically significant change. The decrease in performance of Country A athletes followed a high incidence of steroid detection cases by means of new anti-doping methods. It is highly likely that the consequent performance decrease is due to the implementation of new anti-doping methods. The results of the study bring new facts on the effects of new anti-doping methods implementation and demonstrate following decrease in performance results in population of athletes from the country widely accused of doping use.

Does vitamin D affect strength and speed characteristics and testosterone concentration in elite young track and field athletes in the North European summer?

BACKGROUND: Currently there are no data examining the relationship between the serum concentration of vitamin D bio-chemical marker 25(OH)D and strength and speed characteristics in elite young track and field athletes. Moreover, there are currently no data examining the correlation of vitamin D status with testosterone concentration in elite young track and field athletes. In studies involving members of the general population and athletes from other sports, conflicting data have been reported. MATERIAL AND METHODS: Athletes (n = 68) from both genders took part in this study. Male athletes (n = 23) with mean ± SD age of 18.2 ± 1.9 years and female athletes (n = 45) with mean ± SD age of 17.3 ± 2.6 years participated. All athletes were ranked in the Top-3 in their respective age group and their corresponding results were listed in the Top-20 European records according to https://www.tilastopaja.eu/ in 2021. RESULTS: The average 25(OH)D concentration was 36.5 ± 10.8 ng/mL and 37.8 ± 14.5 ng/mL in male and female athletes respectively. The prevalence of 25(OH)D deficiency (below 20 ng/ml) in both genders was only 5.8%. In the whole group, only 27.9% of athletes had 25(OH)D concentrations between 20 and 30 ng/ml, while 66.2% of athletes had concentrations above 30 ng/ml. There was no difference in vitamin D status between male and female athletes. There was no statistically significant Kruskal-Wallace test correlation between 25(OH)D concentration and performance in the 20 m and 30 m sprint, counter-movement jump and broad jump. There was no correlation between serum concentrations of 25(OH)D and total testosterone in either male or female athletes. CONCLUSION: In elite young track and field athletes who permanently live and train in an area above 50° north latitude, the prevalence of vitamin D deficiency in the summer months was much lower than in previously published studies examining an athletic population, that may be related to the training process. In this specific group of athletes, no correlation was found between serum 25 (OH) D concentration and strength and speed characteristics or total testosterone concentration.

The relative age effect is widespread among European adult professional soccer players but does not affect their market value.

BACKGROUND: The relative age effect (RAE) is most prevalent in highly competitive youth soccer and persists to a lesser extent in senior soccer. However, it is known that soccer players born in the second half of the year are as successful at senior level, indicating that they are equally talented although under-represented at youth level due to bias during the selection process, in which the emphasis is on more pronounced physical qualities in a specific period of time. Examining the prevalence of the RAE among professional soccer players depending on the level of competition and playing position, as well as analyzing the relationship between the player's birth quarter and market value, are of scientific interest. METHODS: The dates of birth, playing position, and market value of all adult male soccer players included in the final rosters of teams from the top-division of 54 European countries, listed on www.transfermarkt.com on August 15th, 2020, were analyzed (18,429 soccer players in total). All players were categorized into four groups according to the quarter of birth (Q) and playing position. All teams were further sub-divided in groups depending on the soccer clubs' level of representation in the UEFA Champions League. RESULTS: Of 18,429 players, 30.9% were born in Q1, 25.7% in Q2, 23.8% in Q3 and 19.6% in Q4. The number of soccer players born in Q1 was lower in less competitive leagues. The number of players born in Q1 decreased as the level of competition decreased; the highest percentage of these players was observed in clubs that are among the top 50 ranked in UEFA or compete in the most prestigious European championships. The RAE was less pronounced in teams that participate in lower competitive championships. There was no significant difference in market value between players playing position and level of competition when born in different quarters. Although, the most expensive soccer players in the European championships were late-born forwards. Players of various groups differed in their market value. CONCLUSIONS: The RAE is currently prevalent in all the most competitive senior soccer leagues and teams in Europe regardless of playing position. There are no significant differences in market value between players of the same playing position and level of competition when born in different quarters. The most expensive soccer players in the European championships are forwards born in Q4. These findings may indicate that the under-representation of "late-born" soccer players in youth, and then consequently in adult soccer, is not associated with lower talent, but with other factors, possibly based on physiological characteristics and socio-cultural factors. Further measures are needed to mitigate the discriminatory effects of selection bias based on the RAE.

The Effect of a Single Dose of Citrulline on the Physical Performance of Soccer-Specific Exercise in Adult Elite Soccer Players (A Pilot Randomized Double-Blind Trial).

PURPOSE: The purpose of this study was to evaluate the effect of a single intake of citrulline at 3 g and 6 g doses in adult elite soccer players performing sport-specific exercise. MATERIALS AND METHODS: This randomized double-blind placebo-controlled study analyzed 18 soccer players from the top divisions of three European countries. Participants were randomized into three groups of six each and performed a field-based soccer-specific test for 18 min. Comparative analysis of heart rate, fatigue and post-exercise recovery was conducted. RESULTS: There were no statistically significant differences in most of the analyzed parameters, nor at any of the time points for lactate concentration. Players' RPE exercise test score did not reveal any differences. CONCLUSIONS: Neither a single intake of 3 g nor of 6 g of citrulline malate affected physical performance, subjective feelings of fatigue or post-exercise recovery in adult elite soccer players who performed a soccer-specific test.

The Physical Demands of Match-Play in Academy and Senior Soccer Players from the Scottish Premiership.

The present study aimed to assess the physical match performance among senior and youth soccer players from an elite Scottish Premiership club during the 2021/2022 season. Twenty-two first team (25.9 ± 4.5 years, 78.3 ± 8.2 kg, 1.82 ± 0.07 cm) and 16 youth players (16.8 ± 0.9 years, 70.1 ± 6.8 kg, 177 ± 5.8 cm) were examined. A selection of physical match performance variables were measured using a global positioning system. Linear mixed-effect regressions revealed for all examined variables no significant differences between first team and U-18 players and no significant differences between playing level by position interaction. Across both teams, Centre Backs compared to Wing Backs, showed a 295 m (p < 0.01) lower high-intensity distance, and performed on average 36 fewer very-high intensity decelerations (p = 0.03). Comparing to Wide Midfielders, Centre Backs showed lower total (1297 m, p = 0.01), high-intensity (350 m, p = 0.01), and sprint (167 m, p < 0.01) distances. Sprint distance was also lower in Centre Backs vs. Strikers (118 m, p = 0.03), and in Central Midfielders vs. both Strikers (104 m, p = 0.03) and Wide Midfielders (154 m, p = 0.01). The present findings highlight the physical match performance of elite Scottish players and provide useful information within the context of understanding how methods of physical development of youth soccer are implemented in different countries.

Sport-Specific Rehabilitation, but Not PRP Injections, Might Reduce the Re-Injury Rate of Muscle Injuries in Professional Soccer Players: A Retrospective Cohort Study.

Platelet-rich plasma (PRP) injections are extremely popular in the management of sports injuries in elite athletes. However, data on the use of various administration protocols of PRP are contradictory. The efficacy of platelet-rich plasma in the treatment of muscle injuries in professional soccer players has to be contextualized within the sport-specific rehabilitation program. Despite the questionable role of PRP, a well-structured rehabilitation program is still regarded as the gold standard. We examined the efficacy of various PRP protocols in the management of muscle injuries in professional soccer players in respect to treatment duration and injury recurrence. A retrospective cohort study. Muscle injuries in professional soccer players (n = 79, height 182.1 ± 5.9 cm, weight 76.8 ± 5.8 kg, BMI 23.1 ± 1.4 kg/m2) from three elite soccer clubs from the Russian Premier League were recorded during the 2018−2019 season. The injuries were graded based on MRI, using the British Athletic Muscle Injury Classification. Treatment protocols included the POLICE regimen, short courses of NSAID administration, and the specific rehabilitation program. The sample group of players were administered PRP injections. The average treatment duration with PRP injection was significantly longer than conventional treatment without PRP, 21.5 ± 15.7 days and 15.3 ± 11.1 days, respectively (p = 0.003). Soccer-specific rehabilitation and obtaining MRI/US before the treatment was associated with significantly reduced injury recurrence rate (p < 0.001). There was no significant difference between the PRP injection protocol applied to any muscle and the treatment duration in respect of grade 2A−2B muscle injuries. The total duration of treatment of type 2A−2B injuries was 15 days among all players. In the group receiving local injections of PRP, the total duration of treatment was 18 days; in the group without PRP injections, the treatment duration was 14 days. In our study, PRP treatment was associated with longer treatment duration, regardless of which muscle was injured. This may reflect the tendency to use PRP in higher-degree injuries. Soccer-specific rehabilitation significantly reduced the injury recurrence rate when compared to the administration of PRP injections. MRI/US imaging before returning to play was also associated with a lower injury recurrence rate. There was no significant difference between the PRP injection protocol applied to any muscle and the treatment duration in treatment of type 2A−2B muscle injuries.

The Immunological and Hormonal Responses to Competitive Match-Play in Elite Soccer Players.

This study aimed to examine the salivary immunoglobulin A (s-IgA) and salivary cortisol (s-Cort) responses to competitive matches in elite male soccer players. Data were collected for 19 players (mean ± SD, age: 26 ± 4 years; weight: 80.5 ± 8.1 kg; height: 1.83 ± 0.07 m; body-fat 10.8 ± 0.7%) from a Russian Premier League team throughout a 6-week period during the 2021-2022 season. Physical match loads were measured through an optical tracking system. s-IgA and s-Cort were assessed one day before each match (MD - 1), 60-min before kick-off, 30-min post-match, and 48-h post-match (MD + 2). At 60-min before kick-off, s-IgA values were lower than at MD - 1 (90% CI difference 15.7-71.3 µg/mL). Additionally, compared to 60-min before kick-off, s-IgA was higher at 30-min post-match (90% CI difference 1.8-57.8 µg/mL) and at MD + 2 (90% CI difference 5.4-60.5 µg/mL). At 30-min post-match, s-Cort was higher than at 60-min before kick-off (90% CI difference 4.84-7.86 ng/mL), while on MD + 2 s-Cort was higher than at 60-min before kick-off (90% CI difference 0.76-3.72 ng/mL). Mixed model regressions revealed that longer playing time and total distance covered, and higher number of high-intensity accelerations, involved smaller s-IgA differences between 30-min post-match and 60-min before kick-off, and between 60-min before kick-off and MD + 2. Additionally, greater high-intensity and sprint distances, and a higher number of high-intensity and maximal accelerations, involved smaller s-Cort differences between 60-min before kick-off and MD + 2. In conclusion, the present results demonstrate that using salivary monitoring combined with match load may be a useful tool to monitor individual mucosal immunity and hormonal responses to match-play and the subsequent recovery periods in elite soccer players.

The Relative Age Effect in the Best Track and Field Athletes Aged 10 to 15 Years Old.

(1) The purpose of this study was to examine the prevalence of the relative age effect (RAE) in the best young (10 to 15 years old) track and field athletes. (2) Hypothesis: The prevalence of the RAE in the best young track and field athletes of both genders will be evident in all age groups from 10 to 15 years old, which may be associated with the significant relationship between biological maturity, chronological age, and the development of physical qualities. (3) Materials and methods: In total, 1778 athletes volunteered for this study. The sample was based on the results of the best young athletes who participated in the final tournaments of the national competition "Shipovka Yunykh"("Running spikes for young athletes"), which have been held since 1981. The sample group consisted of male and female athletes classified into specific age groups: 10 to 11 years old (n = 579), 12 to 13 years old (n = 600), and 14 to 15 years old (n = 599). Analysis was performed using Jamovi 1.8.1. The Chi-square test was used to compare the RAE between different groups. (4) Results: A wide distribution of the RAE was revealed both in the general sample and in boys and girls. The percentage of "early-born" athletes was 37.6% while only 12.3% were "late-born" athletes. The difference in the severity of the RAE may reflect the small sample of athletes from the fourth quartile, which was significantly less than the sample of boys from the fourth quartile (p = 0.04, OR 1.68, 95% CI 1.02−2.78). The RAE was also evident in all age groups of boys and girls, without any statistically significant differences in the severity (p > 0.05, Chi = 2.135, V = 0.02). In the 14- to 15-year-old male athletes group, the number of early-born compared to late-born athletes peaked. The RAE was most common amongst the most successful track and field athletes. Among the competition medalists during the analyzed time period, more than 50% of athletes were born in the first quarter and no athletes were born in the fourth quarter.

Successful Young Athletes Have Low Probability of Being Ranked Among the Best Senior Athletes, but This Is Higher When Compared to Their Less Successful Peers.

Background: Contemporary research has shown that only a small proportion of high achieving young athletes continue to become successful senior athletes. However, there is a lack of empirical literature tracking the success of senior male and female athletes who were considered high achieving as a youth. Hypothesis: Athletes of both sexes who are successful in youth categories (U18 and U20) are more likely to be successful senior athletes. Conclusion: Data from 67,600 athletes were collated from the tilastopaja.org platform. The inclusion criteria for both genders were determined by top-100 ranking in the U18 and U20 age groups and progression to the top-100 as a senior athlete. Only 23.5% of successful track and field athletes (ranked in top-100) at U18 became a successful senior athlete, while 35.4% were from the U20 group. Girls ranked in the top-100 U18 and U20 categories are significantly more likely to be ranked in the top-100 as a senior when compared to boys. Although, being ranked in the top-50 at U18 and U20 significantly increases the probability of becoming a successful senior athlete when compared with less successful athletes at these age groups (p < 0.001). Notably, the majority (68.5%) of the most successful senior athletes were not ranked in the top-100 when in the U18 or U20 age groups. Only a small group of track and field athletes that are successful at U18 and U20 become successful at senior level. The most successful track and field youth athletes are significantly more likely to succeed as a senior athlete than their less successful peers, while girls are more likely to be successful than boys.

The incidence and severity of COVID-19 in adult professional soccer players in Russia.

There are little data on the incidence, and clinical course of COVID-19 among professional soccer players, and the studies examining putative complications of COVID-19 infections are probabilistic. On February 28, the WHO raised the COVID-19 threat assessment to its highest level. The COVID-19 outbreak became a significant challenge for world health. Around 30 million people got infected with COVID-19 since the beginning of this year. More than 900.000 decease. Thus, examining the incidence of COVID-19 and various aspects of its clinical course in a group of adult professional soccer players would be of great practical interest. The incidence, clinical practice, and severity of COVID-19 infection, as well as the duration of treatment and return to play was studied based on a survey of team physicians and medical records assessment in the group of adult professional soccer players representing the clubs of the Russian Premier-League (RPL) during the period of championship resumption from 01.04.2020 until 20.09.2020. COVID-19 infection was detected in 103 soccer players during COVID-19 screening. This number comprises 14.5% of all soccer players on the rosters of RPL soccer teams and is subjected to regular COVID-19 testing. The asymptomatic course was observed in 43.7% of cases (n = 45). These players were isolated, and their clinical condition was monitored closely. In 56.3% of patients (n = 58), fatigue, headache, fever, and anosmia were the most common symptoms. COVID-19 infection was commonly diagnosed among adult professional soccer players in Russia. However, most cases had a mild course and did not impair return to regular exercise. Only two players were hospitalized with lung lesions and returned to regular sports.

Conservative Treatment of the Fifth Metatarsal Bone Fractures in Professional Football Players Using Platelet-Rich Plasma.

Injuries of the metatarsal bones in football are relatively rare and in most cases are localized in the fifth metatarsal. The gold standard of the diagnosis of fractures in this area can be X-rays, which in most cases allows verifying the diagnosis. The treatment tactics depend on the localization of the fracture according to Lawrence and Botte's classification: 3 zones of localization are distinguished. Fractures located in zones 2 and 3 belong to a high-risk group due to delayed consolidation and nonunion and therefore athletes are most often treated with osteosynthesis using intramedullary screws. The minimal recovery time for this type of treatment is at least 8 weeks. This report describes 7 cases of the fifth metatarsal bone fractures, located in zones 2 and 3 in professional football players who were treated with an immobilization boot, cryotherapy, nutritional supplements of calcium and vitamin D, and local injections of platelet-rich plasma, which contains numerous growth factors. The deadline for returning to regular training activities was 43 to 50 days, and there was no relapse of damage within 6 months of follow-up.Levels of Evidence: Level of evidence 4: case report study.