To be able to value the relative age effect in the male and female World Championships played between 2005 and 2010 in the U17 categories (athletes 17 years or younger), U19 (athletes 19 or younger) and U21 (athletes 21 years or younger) a sample of 954 players has been selected. The variables registered were their dates of birth, the category of the competition, gender, height and official statistics of each player obtained from the International Basketball Federation (FIBA). A clear relative age effect was found (in both male and female categories) fading with age, being higher in the U17 category, slightly less but also significant in the U19, and no significant effect found in U21. This effect persists when the different specific positions were analysed in the male categories, being clearer in the positions that require more physical strength. In female categories the results do not back the existence of the relative age effect. Also, differences were found in height in the male category with regard to the players’ year-quarter of birth, but its interpretation is not consistent with the relative age effect. In the female category no differences were found in height. Finally, the performance difference of the players in the male and female categories hardly varies with regard to the year-quarter of birth.

Home advantage has been studied in different sports, establishing its existence and its possible causes. This article analyzes the home advantage in soccer leagues of UEFA countries in the first part of the 21st century. The sample of 52 countries monitored during a period of 10 years allows us to study 520 leagues and 111,030 matches of the highest level in each country associated with UEFA. Home advantage exists and is significant in 32 of the 52 UEFA countries, where it equals 55.6%. A decrease can be observed in the tendency towards home advantage between the years 2000 and 2010. Values between 55 and 56 were observed for home advantage in the top ten leagues in Europe. It has also been observed that home advantage depends on the level of the league evaluated using UEFA’s 2010/11 Country coefficients. The home advantage is calculated taking into account the teams’ position and the points obtained in each of the leagues. A direct relationship was observed with the number of points gained and an inverse relationship was observed with the team position.

Prospective studies on injuries in martial arts competition are scarce, especially those involving young practitioners, but the upsurge of children and adolescents taking part in organized training and competition in these sports requires clarification of the injury risk that they represent for youths. Top-level karate competition for young adolescents (cadets, or 14- to 15-year-olds) has a low injury rate and can be safely promoted. Descriptive epidemiological study. Prospective recording of the injuries resulting from all bouts in 3 consecutive World Karate Championships (2009, 2011, and 2013) for cadets was performed. Data were collected prospectively in situ with checklists that described competitor sex, bout category, and weight as well as injured area, diagnosis, mechanism of injury, severity, and treatment. A total of 1020 bouts were reviewed, 671 in the male category and 349 in the female category. A total of 61 injuries were recorded. Of those, only 3 were time-loss injuries. During the 2009 and 2011 championships, there was 1 injury per 25.6 fights, while during the 2013 championship the number of injuries increased, with 1 injury per 10 fights (P = .003). There was no statistical difference in the total injury rate between the male and female categories (P = .71), with an odds ratio of 1.16 (95% CI, 0.52-2.55). The injury rate for cadet top-level karate competition found in this prospective study is much lower than the rates previously published for karate or other martial arts competitions, but there seems to be a marked increase as more championships are held, which is a matter of concern.

Background Although it is well known that injuries occur in combat sports, the true incidence of concussions is not clearly defined in the literature for karate competition. Aim To determine the incidence of concussions in top-level (World Karate Federation World Championships) karate competition. Methods Injuries that took place in 4 consecutive World Karate Championships (from 2008 to 2014) were prospectively registered. A total of 4625 fights (2916 in the male category and 1709 in the female category) were scrutinised, and concussions were identified and analysed separately for frequency (rate per fight) and injury risk. Results A total of 4 concussions were diagnosed by the attending physicians after carrying out athlete examinations. Globally, there was 1 concussion in every 1156 fights, or 0.43/1000 athlete-exposures (AE). In male athletes, the rate of concussion was 1/5832 min of fighting, and in female athletes, it was 1/6836 min. OR for concussion in women is 0.57 (95% CI 0.06 to 5.47; z=0.489; p=0.6249) and risk ratio for concussions in men is RR 1.478 (95% CI 0.271 to 8.072), p=0.528, representing a higher risk of definite concussions in men than in women, but not statistically significant. There is not a significantly higher risk of concussions in team competition (no weight limit) when compared with individual competition (held with strict weight limits for each category). Conclusion The risk of concussions in top-level karate competition is low, with a tendency for an increased risk for men and for competition without weight limits, but not statistically significant with respect to women or individual competition.

Maximum heart rate (MHR) is widely used in the prescription and monitoring of exercise intensity, and also as a criterion for the termination of sub-maximal aerobic fitness tests in clinical populations. Traditionally, MHR is predicted from an age-based formula, usually 220 – age. These formulae, however, are prone to high predictive errors that potentially could lead to inaccurately prescribed or quantified training or inappropriate fitness test termination. In this paper, we used functional data analysis (FDA) to create a new method to predict MHR. It uses heart rate data gathered every 5 seconds during a low intensity, sub-maximal exercise test. FDA allows the use of all the information recorded by monitoring devices in the form of a function, reducing the amount of information needed to generalize a model, besides minimizing the curse of dimensionality. The functional data model created reduced the predictive error by more than 50% compared to current models within the literature. This new approach has important benefits to clinicians and practitioners when using MHR to test fitness or prescribe exercise.