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.

Sports and Weight Control in Children.

Pediatric obesity is a global concern with distressing comorbid conditions, including mood disturbance, cardiovascular changes, endocrine imbalance, liver disease, sleep apnea, and orthopedic conditions. The primary treatment of this condition includes physical activity. Participating in organized sports has been shown to reduce weight and the complications of pediatric obesity more effectively than individual exercise.

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.

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.

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.

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 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.

Community-Acquired Acinetobacter radioresistens Bacteremia in an Immunocompetent Host.

Acinetobacter species are gram-negative coccobacilli ubiquitous in nature and widely distributed in the environment. Acinetobacter baumannii is a bacteria commonly seen in the hospital setting, responsible for causing a wide range of bloodstream infections, urinary tract infections, secondary meningitis, infective endocarditis, and wound infections, and is the cause of outbreaks mainly due to its antimicrobial resistance patterns. The use of broad-spectrum antibiotic coverage with carbapenems is essential in the hospital setting. Therefore, carbapenem-resistant Acinetobacter baumannii (CRAB) poses as a very challenging pathogen. Acinetobacter radioresistens, a rare species in comparison to the more prevalent Acinetobacter baumannii, is an underestimated agent in causing nosocomial infections and also is a potential disseminator of resistance genes. It is also resistant to gamma radiation at 4-8 times higher than other Acinetobacter spp. and is the source of the class D OXA-23 carbapenemase that can confer carbapenem resistance. Therefore, immediate and precise identification of A. radioresistens is crucial for the clinical management of multidrug-resistant bacteremia.

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 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.

The Prevalence of Use of Various Post-Exercise Recovery Methods after Training among Elite Endurance Athletes.

There is now compelling evidence of the effectiveness of a range of post-exercise recovery techniques, including extended nights of sleep, cold water immersion, massage, and compression garments. Currently, limited information is available on post-exercise recovery methods used by elite endurance athletes. Therefore, this study investigated the actual methods of recovery used in this group of athletes. Google Forms were used to collect information on the recovery methods used by elite endurance track and field athletes (n = 153, 61.4% men, 38.6% women; average age: 22.7 ± 4.6 years). The most used methods of recovery were sauna bathing (96.7%), massage (86.9%), daytime nap (81.0%), and long night sleep (at least 9h) (61.4%). Recovery methods with proven effectiveness such as cold water immersion and compression garments were rarely used (15.0% and 7.8%, respectively). Overall, recovery methods were used more often when the tiers of the track and field athletes were higher. Massage and sauna bathing were the most used methods of post-exercise recovery among Russian endurance track and field athletes. In most cases, they were used in conjunction with short daytime nap and long night sleep. Higher tier athletes were more likely to use sauna bathing, massage, long night sleep, and daytime nap but not cold water immersion and compression garments as recovery methods; however, all these methods except for cold water immersion were widely used among elite-tier athletes.

Markers of muscle damage and strength performance in professional football (soccer) players during the competitive period.

BACKGROUND: The present study investigated the impact of competitive soccer on the short-term changes in isometric strength of the adductor muscle group during the competitive season. METHODS: In this cohort study we evaluated the association between a serum marker of muscle damage [creatine phosphokinase (CPK)] and isometric strength of the adductor muscles of the hip in 30 professional football players (age: 26.7±2.9 years) during two seasons of the national top-level championship. Serum CPK level was determined the day before the match, 12-20, 36-48, 60-72 h after the match. The maximum voluntary isometric contraction force of the adductor muscles complex was determined immediately after having taken blood samples. RESULTS: There was evidence of a statistically significant positive association between age, body mass index (BMI), percentage of body fat, and muscle strength, and between weight and muscle strength. There was evidence of a statistically significant negative association between the level of CPK and the maximum isometric strength of the adductors of soccer players. Changes in CPK levels were associated with the muscle strength recovery trend (P<0.001). The strength/CPK ratio at different time points had a U-shaped curve. CONCLUSIONS: Exercise induced muscle damage significantly affects the strength of the adductor muscle group of professional soccer players during the competitive period. The lower the CPK level, the greater the athletes' strength at a given time point. Also, the greater the decrease in CPK level, the greater the rate of strength restoration.

Asymptomatic Foot and Ankle Abnormalities in Elite Professional Soccer Players.

BACKGROUND: Professional soccer players are often evaluated with asymptomatic lesions of the ankle and foot, and such abnormalities may eventually become clinically relevant. PURPOSE: To ascertain the prevalence of foot and ankle abnormalities in elite professional adult soccer players. STUDY DESIGN: Case series; Level of evidence, 4. METHODS: Professional adult male elite soccer players (n = 37) underwent magnetic resonance imaging (MRI) scans of both their feet and ankles. All competed for their respective national junior or adult soccer teams. MRI scans were performed with 1.5-T scanners and analyzed independently by 2 experienced radiologists. RESULTS: The MRI scans of 86.5% of the players showed degenerative joint disease (DJD) in at least 1 of the joints of the foot and ankle. Articular cartilage lesions in the joints of the foot and ankle were evident in 42% of the scans. Of all lesions, 17% were grade 3 or 4 (Noyes and Stabler classification) cartilage lesions and accompanied by subchondral bone marrow edema. The greater the age, weight, and height of the players, the greater was the odds ratio of DJD of the ankle joint. Synovitis in at least 1 of the joints of the foot was detected in 64% of the MRI scans. Leg dominance significantly correlated with bone marrow edema of the talus. CONCLUSION: Elite professional soccer players are often evaluated with a high prevalence of asymptomatic osteochondral lesions with subchondral bone marrow edema in the foot and ankle. These osteochondral lesions may remain asymptomatic or, with the continuing high-intensity stresses that modern professional soccer demands of its athletes, may evolve and cause foot and ankle pain. It is unclear whether and which interventions can be implemented to prevent the occurrence of these abnormalities in the first place.

Asymptomatic Degenerative Changes in the Lumbar Spine Among Professional Soccer Players.

STUDY DESIGN: Cross-sectional study. OBJECTIVE: The aim of this study was to evaluate the actual prevalence of degenerative spinal changes and their association with age in a cohort of professional soccer players. SUMMARY OF BACKGROUND DATA: Presently, there are data that athletes have more degenerative changes than nonathletes; however, the research examining the prevalence of degenerative spinal conditions among professional elite soccer players is scarce. METHODS: Professional male soccer players were included in the study (n = 40, average age 26,6 ±â€Š4,5 years, average height 18 ±â€Š0.07 m, weight 76.7 ±â€Š7.1 kg). Lumbosacral spine MRI scanning at the L1-S1 level has been performed. Two radiologists with at least 7 years of experience of working with athletes evaluated all images independently of each other. RESULTS: 92.5% (n = 37) of soccer players had ≥1 spinal degenerative condition. Thirty-five percent (n = 14) of players had three to five, and 50% (n = 20) had six or more conditions. The average age of players who had six or more conditions was significantly higher than those who had zero to five or three to five conditions-28.1 ±â€Š4.8 years versus 25.1 ±â€Š3.6 years (P = 0.029), and 24.8 ±â€Š3.6 years, respectively.Kruskal-Wallis test has shown no association between the number of degenerative conditions and weight (P = 0.98) as well as body mass index (P = 0.99). The age was associated with degenerative changes (P = 0.008).Disc desiccation was the most common pathologic condition, which was found in 82.5% of athletes. Facet joint arthropathy and spondylosis were present in 70, and 50% of the studied lumbar spine MRI scans, respectively. The spondylolysis prevalence of 20% was noted. CONCLUSION: Elite professional soccer players demonstrate a high prevalence of asymptomatic degenerative lumbar spinal degenerative changes, which are significantly associated with age. These conditions might lead to the development of symptomatic lower back pain, given the high-intensity exercise required in professional soccer. It is presently unclear what measures might be applied for the primary prevention of these degenerative spinal conditions.Level of Evidence: 4.

The prevalence of non-contact muscle injuries of the lower limb in professional soccer players who perform Salah regularly: a retrospective cohort study.

BACKGROUND: The present study assessed the prevalence of non-contact muscle injuries of the lower limbs, including hamstring injuries, in professional Russian soccer players who regularly perform Salah, an obligatory Muslim prayer performed 5 times a day. METHODS: Using a retrospective cohort study design, 68 professional male soccer players (excluding goalkeepers), 34 of whom were Muslims regularly performing Salah (exposure group) and 34 were randomly chosen non-Muslim players (control group), were included in the study. The groups were similar in their playing leagues, field positions, age (27 ± 3.1 vs 28 ± 4.2 years), and body mass index (22 ± 1.2 vs 23 ± 0.92 kg/m2). RESULTS: The incidence of hamstring injury was significantly lower in the exposure group (2 vs 14, p = 0.0085). A declining trend for the number of muscle injuries (either hamstring or not) was observed in the exposure group (11 vs 27, p = 0.0562). Two players in the exposure group and 11 in the control group (p = 0.0115, OR 0.1307, 95% CI 0.0276 to 0.5698) suffered a hamstring injury, with no statistically significant difference in the occurrence of other injuries. The total amount of the training and play days missed because of hamstring and other muscle injuries was significantly lower in the exposure group (24 vs 213 days, p = 0.0043, and 200 vs 344 days, p = 0.0066, respectively). CONCLUSION: The prevalence of non-contact muscle injuries, including hamstring injuries, was lower in professional Russian soccer players who regularly performed Salah.

Relative Age Effect in Russian Elite Hockey.

Bezuglov, E, Shvets, E, Lyubushkina, A, Lazarev, A, Valova, Y, Zholinsky, A, and Waskiewicz, Z. Relative age effect in Russian elite hockey. J Strength Cond Res 34(9): 2522-2527, 2020-A considerable amount of literature has been published on relative age effect (RAE) in many sports; however, only a few studies have investigated this phenomenon in European elite ice hockey. The objective of this research was to study RAE prevalence in Russian elite ice hockey, which for years has been holding leading positions in global ice hockey. To estimate RAE prevalence, birthdates of recruits of leading ice hockey academies, players of the leading junior and adult teams, and most successful Russian-born National Hockey League (worlds' strongest ice hockey league) players were identified (n = 2,285). A high prevalence of RAE was identified. The number of players born in the first half of the year was higher than those born later in the year-65.5 and 34.5%, respectively. The RAE prevalence was high among all age groups of recruits of the leading Russian hockey academies and junior teams. In contrast to junior hockey, more players born in the fourth quarter of the year were identified in elite adult teams. The high prevalence of RAE in Russian hockey might be explained by the fact of a high level of competition among young players during recruitment to hockey academies. Moreover, the coaches aim to achieve immediate progress, thus selecting more mature players who are better physically developed. However, "later-born" are widely present in elite adult ice hockey leagues.

The Effect of Training Experience and Leg Dominance on the Prevalence of Asymptomatic Intraarticular Changes of the Knee Joints in Adult Professional Male Soccer Players.

BACKGROUND: Currently, no data is available regarding the association between professional experience or limb dominance and the prevalence of asymptomatic knee joint lesions in adult professional male soccer players. HYPOTHESIS: The prevalence of the accumulated changes increases with training experience. This is especially true for the dominant leg, which is involved in a large proportion of the athletes' movements. STUDY DESIGN: Level 2 cross-sectional cohort study METHODS: MRI was used to assess the condition of 94 knee joints in 47 adult professional male soccer players (mean age 25.7 ± 4.6 years, BMI 22.8 ± 1.4). Previous surgery on joints was an exclusion criterion. No football player had knee injuries (including fresh bruises) for at least 3 months before the examination. All the scans were performed using a 1.5T MRI scanner and a slice thickness of 3 mm. The images were blindly analyzed by two experienced radiologists. We analyzed all the three compartments of the knee joint. We consider a chondral lesion already from grade I in modified Noyes and Stabler classification system. To assess the influence of soccer training experience, all players were divided into two groups: group 1 formed from players with less than 20 years of experience and group 2 with more than 20 years of experience. RESULTS: One hundred percent of the soccer players had at least one chondral and meniscal lesion. In both legs, the posterior horn of the medial meniscus (95.6%) was the most frequent site of injury. Most of the injuries were classified as grade II injuries (73.3% for the dominant and 75.6% for the non-dominant leg). Experience and age of the athletes significantly increased the probability of subcortical bone lesions. They were significantly positively correlated with the grades of patellar lesions and lesions of the patellar surface of the femur and significantly negatively correlated with the grades of lesions of posterior horn of lateral meniscus and anterior horn of medial meniscus. No statistically significant differences in the prevalence and grades of cartilage and meniscal lesions in the dominant and non-dominant limb were observed. CONCLUSION: Soccer practice is associated with the increased prevalence of asymptomatic chondral and meniscal lesions. The probability of subcortical bone lesions significantly increases with training experience and age. These factors are also positively correlated with the grades of patellar lesions and lesions of the patellar surface of the femur. The prevalence and grade of asymptomatic chondral and meniscal lesions is independent of leg dominance.