Injuries and illnesses during the 2011 Paris European Athletics Indoor Championships

This study aimed to record and analyse incidence and characteristics of injuries and illnesses incurred during the Indoor Athletics Championships. During the 2011 European Indoor Athletics Championships in Paris, incidence and characteristics of new injuries and illnesses were recorded prospectively by physicians and physiotherapists from national teams and local organizing committee in 631 registered athletes. Around 70% of athletes were covered by the medical teams (response rate: 84%). Thirty injuries, including eight time‐loss injuries, were reported, representing an incidence of 47.5 injuries and 29.4 time‐loss injuries per 1000 registered athletes. Injury and time‐loss injury risk were highest in heptathlon and hurdles. Three‐quarters of injuries affected the lower extremity. Thigh strain was the most common diagnosis (n = 7; 23%). Noncontact trauma (n = 9; 30%) was the predominant cause. A total of 18 illnesses were reported. Incidence of illnesses was 28.5 per 1000 registered athletes, with 17% resulting in time lost from sport. Upper respiratory tract infection was the most common diagnosis (n = 8; 44%) followed by upper respiratory tract allergy (n = 3; 17%) and gastroenteritis (n = 3; 17%). Injury and illness incidence and severity were lower during the 2011 European Indoor Athletics Championships than during outdoor championships, probably due to the shorter duration, the fewer number of events, and shorter sprint distances.     

Motor pattern of the knee joint muscles during side-step cutting in European team handball. Influence on muscular co-ordination after an intervention study

The incidence of anterior cruciate ligament (ACL) injuries is reported to be high in many popular team sports The most risky movement in European team handball is reported to be the side-step cutting manoeuvre. Well-rehabilitated ACL-deficient athletes have been shown to have increased co-contraction about the knee joint with this manoeuvre. The aim of this study was to examine the effect of a prophylactic training programme on the co-contraction of the knee joints of non-injured European team handball players The subjects performed 'match-like' cutting manoeuvres on a force platform. EMG-signals from the involved knee joint muscles and force platform signals were simultaneously stored on a personal computer. The data collected before and after a 12-week prophylactic training program were compared. The results demonstrated that rehabilitation exercises cannot increase co-contraction about the knee joint in healthy athletes during side-step cutting. This is contradictory to the reported effect on ACL-deficient athletes.     

Motivational cues predict the defensive system in team handball: A model based on regulatory focus theory

This study was based on the naturalistic decision‐making paradigm and regulatory focus theory. Its aim was to model coaches' decision‐making processes for handball teams' defensive systems based on relevant cues of the reward structure, and to determine the weight of each of these cues. We collected raw data by video‐recording 41 games that were selected using a simple random method. We considered the defensive strategy (DEF: aligned or staged) to be the dependent variable, and the three independent variables were (a) numerical difference between the teams; (b) score difference between the teams; and (c) game periods. We used a logistic regression design (logit model) and a multivariate logistic model to explain the link between DEF and the three category independent variables. Each factor was weighted differently during the decision‐making process to select the defensive system, and combining these variables increased the impact on this process; for instance, a staged defense is 43 times more likely to be chosen during the final period in an unfavorable situation and in a man advantage. Finally, this shows that the coach's decision‐making process could be based on a simple match or could require a diagnosis of the situation based on the relevant cues.     

Clinical, functional, and radiologic outcome in team handball players 6 to 11 years after anterior cruciate ligament injury: a follow-up study

BACKGROUND: Long-term outcome after anterior cruciate ligament injury among top-level pivoting athletes is unknown. PURPOSE: To evaluate outcome among competitive team handball players after anterior cruciate ligament injury. STUDY DESIGN: Prospective cohort study. METHODS: A previously studied group of 86 elite players who had an anterior cruciate ligament rupture were invited to participate in follow-up evaluations a mean of 7.8 years later. RESULTS: Among the 57 operatively treated patients who returned for follow-up, 33 (58%) returned to team handball at their preinjury level, compared with 18 of 22 (82%) in the nonoperative group. Eleven of the 50 players (22%) who continued playing reinjured their anterior cruciate ligament when playing team handball. The overall Lysholm score was 85 +/- 13 in both groups, but the five players classified as poor were all operatively treated. Nearly half of the players had an International Knee Documentation Committee classification of abnormal or severely abnormal. There were significant differences between the injured and uninjured leg in functional (2.5% to 8%), strength (3.8% to 10.1%), and KT-1000 arthrometer tests (27%). In the operatively treated group, 11 developed radiologic gonarthrosis, compared with 6 in the nonoperatively treated group. There was no correlation between radiologic findings and pain scores. CONCLUSION: A more restrictive attitude regarding return to competitive pivoting sports after anterior cruciate ligament injury may be warranted.     

Imaging overuse injury of the elbow in professional team handball players: a bilateral comparison using plain films, stress radiography, ultrasound, and magnetic resonance imaging

The purpose of this study was to compare the manifestations of elbow stress due to repetitive valgus forces between the dominant and the non-dominant elbow in 40 uninjured elite team handball players using plain films, stress radiographs, ultrasound, and MRI examination. On comparative plain films generalized bony hypertrophy manifested by increased humeral diameter, and cortical hypertrophy of the humeral shaft of the dominant extremity was observed in all players. A significantly greater difference in medial joint space opening between stressed and unstressed elbows was measured in the dominant elbow compared with the non-dominant elbow (0.41 +/- 0.59 mm). The ultrasonographic findings showed statistically significant bilateral differences in the thickness of the flexor-pronator tendon (0.90 +/- 0.56 mm), extensor tendon (0.96 +/- 0.50 mm), triceps tendon (0.69 +/- 0.27 mm), and medial collateral ligament (0.47 +/- 0.24 mm): the values were systematically higher on the dominant side. US examination showed intra-articular effusions in 67% and small loose bodies in 33.3% of the players, exclusively in dominant elbows. MRI showed joint effusion in the same subjects as US, but loose bodies were only detected in half of the cases found by ultrasound. This study demonstrates that repetitive stress on the dominant extremities of handball players is responsible for physiologic and pathologic changes in the dominant elbow.     

Investigating predictors of ball-throwing velocity in team handball: the role of sex,anthropometry, and body composition

Purpose

In this work we investigated the role of sex, anthropometry and body composition in predicting ball-throwing velocity in skilled team handball players of different competitive level.

Methods

Forty-six handball players (22 males, 24 females) underwent standard anthropometry and body composition analysis using dual-energy X-ray absorptiometry. Ball-throwing velocity in standing throw from 7 m and three-step running throw from 9 m to a left and right goal was evaluated on court using a radar gun.

Results

Results showed that males throw faster than females in all types of throw, independently of several confounding variables. In both sexes, after correction for several confounding variables, bone mineral content and/or density positively correlated with ball-throwing velocity in all types of throw, but lean and fat mass did not. To minimize collinearity problems, we used the sophisticated Random Forests approach to select variables for regression analysis. In the resulting models, bone mineral content and/or density emerged as sole predictors of ball-throwing velocity to a limited (adjusted R ² = 0.10–0.36) albeit significant extent.

Conclusions

It is concluded that, besides sex, the athlete’s bone quality may affect handball-throwing performance, suggesting that specific training aimed at improving bone quality would be of use to players.

     

Facilitators to support the implementation of injury prevention training in youth handball: A concept mapping approach

There is a need for research to identify effective implementation strategies for injury prevention training within real‐world community sports. The aim of this ecological participatory study was to identify facilitators, among stakeholders at multiple levels, that could help injury prevention training become part of regular training routines in youth team handball. Concept mapping, a mixed‐method approach for qualitative data collection and quantitative data analysis, was used. Stakeholders (n = 196) of two community team handball clubs (29% players, 13% coaches, 38% caregivers, 11% club, district and national handball administrators, 9% unknown) participated in a brainstorming process. After the research team synthesized the 235 generated statements, 50 stakeholders (34% players, 22% coaches, 24% caregivers, 20% administrators) sorted 89 unique facilitator statements into clusters and rated them for importance and feasibility. Multidimensional scaling and hierarchical cluster analysis yielded five clusters (stress value 0.231): “Understanding and applying knowledge,” “Education, knowledge, and consistency,” “Set‐up and exercises,” “Inspiration, motivation, and routines,” and “Club policy and expert collaboration.” The cluster “Understanding and applying knowledge” had the highest mean importance (3.17 out of 4) and feasibility (2.93) ratings. The 32 statements rated as both highly important and feasible (Go‐zone) indicate action is required at the individual (end‐users) and organizational (policymakers) levels to implement injury prevention training. Results suggest that developing evidence‐based context‐specific injury prevention training, incorporating physiological, biomechanical and psychological components, and an associated context‐specific implementation plan in partnership with all stakeholders should be a high priority to facilitate the implementation of injury prevention training in youth team handball.     

Epidemiology of injuries during the Wheelchair Basketball World Championships 2018: A prospective cohort study

Several international sports federations have implemented a standardized injury reporting system during their championships. However, very few studies have investigated athletes with disabilities during major championships apart from the Paralympic Games. Therefore, the aim of this study was to assess the rate and characteristics of injuries during the Wheelchair Basketball World Championships 2018 (WBWC). This prospective cohort study was conducted during the WBWC held in Hamburg, Germany, from August 16 to August 26, 2018. Physicians or physiotherapists of all 28 participating teams (total 336 players) were asked to report all newly incurred injuries (with location, diagnosis, cause, and estimated duration of absence) daily on a standardized injury report form. Prevalence and incidence rates were calculated. Medical staff of 11 teams (132 players) reported 100 injuries, equivalent to 75.8 per 100 players (95% CI: 60.9-90.7) or 68.9 per 1000 player-days (55.4-82.4). Eight time-loss injuries were reported (6.1 injuries per 100 players [95% CI: 1.9-10.3] or 5.5 injuries per 1000 player-days [1.7-9.3]). More injuries were incurred during matches (n = 68) than during training. Most injuries affected the neck/cervical spine (16%), thoracic spine/upper back (15%), and shoulder (14%). The most frequent diagnosis was muscle spasms (25%), the most frequent cause was overuse (52%). A high rate of non–time-loss injuries compared to Paralympic Games was reported. Future studies should focus on the etiology of muscle spasms and further identify injury mechanisms of traumatic and overuse injuries in wheelchair basketball players to develop adequate preventive measures.     

Core body temperature during competition in the heat: National Boys' 14s Junior Championships

Objective

To examine on‐court core body temperature (T_C) and sweat loss, as well as pre‐ and post‐play hydration status, in elite adolescent tennis players during a national championships event in a hot climate.

Methods

Eight healthy, fit, young male tennis players (mean (SD) age 13.9 (0.9) years; mass 56.0 (10.7) kg; height 169.2 (14.7) cm) were evaluated during first‐round singles competition at the National Boys'' 14s Junior Championships in the heat (wet‐bulb globe temperature (WBGT) 29.6 (0.4) °C). Five of those same players were also evaluated during a same‐day doubles match (WBGT 31.3 (0.5) °C).

Results

During doubles (4.37 (0.35) h after singles), pre‐play urine specific gravity (USG) (1.025 (0.002); p = 0.06) and total sweat loss (1.9 (0.2) litres; p = 0.10) tended to be higher before and during doubles, respectively, compared to singles. However, percentage change in body mass (−0.5 (0.3) %) tended to be comparatively less (p = 0.08), even though the doubles matches were generally longer (106.6 (11.2) vs 78.8 (10.9) min; p = 0.09) and the degree minutes total was greater (p = 0.04). T_C increased (p<0.001) during singles and remained elevated, even after 10 min following the end of play. Notably, pre‐play (singles) USG was strongly associated (p = 0.005) with the players'' final T_C (38.7 (0.3) °C) recorded at the end of singles play.

Conclusion

Junior tennis players who begin a match not well hydrated could have progressively increasing thermal strain and a greater risk for exertional heat illness as the match advances.Most junior tennis tournaments are played outdoors in warm to hot climates. Even as the level of play and depth of competition continue to improve, the toughest opponent these young players often face is the heat. The consequent effects on a child''s health, safety and performance are well recognised.^{1,2,3,4,5,6,7,8} To date, only one study has examined core body temperature (T_C) responses on‐court in junior tennis players.⁹ Notably, however, there have been no assessments of T_C during actual competition, where the levels of stress and effort are likely to have a comparatively greater effect on behaviour and physiological responses.In this study, we examined T_C in adolescent tennis players during a national championships event in a very hot climate. Hydration status and sweat loss were also examined. We were not only interested in assessing the degree of heat strain incurred on the court; we also wanted to particularly determine the associations between pre‐ and post‐match hydration status and T_C. Recently, the relationship between level of hydration and T_C as observed in laboratory studies, respective to its relevance in field settings, has been a contentious issue in the literature.^10,11,12 We hypothesised that hydration status before and after play would be related to the degree of thermal strain at least during singles play. We also wanted to examine on‐court T_C responses during a second (doubles) match on the same day, given that doubles is often perceived as not as likely to elicit an appreciable thermal challenge.These findings provide unique insight to T_C responses in elite adolescent tennis players during actual competition. The combination of heat stress and scheduling of multiple same‐day matches in junior tennis can measurably impact performance¹³ and often prompts incidents of heat illness (M F Bergeron, unpublished observations). Our goal is that, as more research such as this is conducted, there will be enough information and insight to establish more specific and effective guidelines for enhancing the safety and performance of junior tennis players during tournaments through more appropriate scheduling of matches and events, as well as match preparation and recovery strategies.     

Discharges during U.S. Army basic training: injury rates and risk factors

This study examined injury rates and risk factors for discharge in a cohort of 756 men and 474 women in U.S. Army basic combat training (BCT) at Fort Jackson, South Carolina. Investigators systematically screened trainee medical records for injuries and collected medical recommendations to temporarily remove a trainee from BCT to allow recovery from an injury. The BCT unit provided Army Physical Fitness Test (APFT) scores and trainee demographic data. Discharges were identified by reviewing discharge packets and were confirmed through rosters from the BCT units. There were 102 men and 108 women discharged. Person-time injury incidence rates (for time-loss injuries) among discharged and nondischarged men were 1.87 and 0.45 cases/100 person-days, respectively (p < 0.01); the rates for discharged and nondischarged women were 1.95 and 1.01 cases/100 person-days, respectively (p < 0.01). Men had a higher risk of discharge if they had a time-loss injury (p < 0.01), but women did not (p = 0.28). Other discharge risk factors for both men and women included a medical recommendation for removal from training to recover from an injury, lower performance on any of the three APFT events, and lower educational level. Women with more body mass or a higher body mass index also had a marginally higher risk of discharge.     

Psychological issues related to injury in athletes and the team physician: a consensus statement

This document provides an overview of selected medical issues that are important to team physicians who are responsible for the care and treatment of athletes. It is not intended as a standard of care, and should not be interpreted as such. This document is only a guide, and as such, is of a general nature, consistent with the reasonable, objective practice of the healthcare profession. Adequate insurance should be in place to help protect the physician, the athlete, and the sponsoring organization.     

Force experienced by the head during heading is influenced more by speed than the mechanical properties of the football

There are growing concerns about the risk of neurodegenerative diseases associated with heading in football. It is essential to understand the biomechanics of football heading to guide player protection strategies to reduce the severity of the impact. The aim of this study was to assess the effect of football speed, mass, and stiffness on the forces experienced during football heading using mathematical and human body computational model simulations. Previous research indicates that a football header can be modeled as a lumped mass mathematical model with elastic contact. Football headers were then reconstructed using a human body modeling approach. Simulations were run by independently varying the football mass, speed, and stiffness. Peak contact force experienced by the head was extracted from each simulation. The mathematical and human body computational model simulations indicate that the force experienced by the head was directly proportional to the speed of the ball and directly proportional to the square root of the ball stiffness and mass. Over the practical range of ball speed, mass, and stiffness, the force experienced by the head during football heading is mainly influenced by the speed of the ball rather than its mass or stiffness. The findings suggest that it would be more beneficial to develop player protection strategies that aim to reduce the speed at which the ball is traveling when headed by a player. Law changes reducing high ball speeds could be trialed at certain age grades or as a phased introduction to football heading.