Elite football teams that do not have a winter break lose on average 303 player-days more per season to injuries than those teams that do: a comparison among 35 professional European teams

2018 ◽  
Vol 53 (19) ◽  
pp. 1231-1235 ◽  
Author(s):  
Jan Ekstrand ◽  
Armin Spreco ◽  
Michael Davison
Keyword(s):  
Linear Regression ◽  
The Other ◽  
Climatic Region ◽  
Time Loss ◽  
Severe Injuries ◽  
Injury Rates ◽  
Level Data ◽  
Injury Burden ◽  
Or Team ◽  
Individual Training

ObjectiveTo compare injury rates among professional men’s football teams that have a winter break in their league season schedule with corresponding rates in teams that do not.Methods56 football teams from 15 European countries were prospectively followed for seven seasons (2010/2011–2016/2017)—a total of 155 team-seasons. Individual training, match exposure and time-loss injuries were registered. Four different injury rates were analysed over four periods within the season, and linear regression was performed on team-level data to analyse the effect of winter break on each of the injury rates. Crude analyses and analyses adjusted for climatic region were performed.Results9660 injuries were reported during 1 447 011 exposure hours. English teams had no winter break scheduled in the season calendar: the other European teams had a mean winter break scheduled for 10.0 days. Teams without a winter break lost on average 303 days more per season due to injuries than teams with a winter break during the whole season (p<0.001). The results were similar across the three periods August–December (p=0.013), January–March (p<0.001) and April–May (p=0.050). Teams without a winter break also had a higher incidence of severe injuries than teams with a winter break during the whole season (2.1 severe injuries more per season for teams without a winter break, p=0.002), as well as during the period January–March (p=0.003). A winter break was not associated with higher team training attendance or team match availability. Climatic region was also associated with injury rates.ConclusionsThe absence of a scheduled winter break was associated with a higher injury burden, both before and during the two periods following the time that many European teams take a winter break. Teams without a winter break (English clubs) had a higher incidence of severe injuries following the time of the year that other teams (other European clubs) had their scheduled break.

scholarly journals FAIR PLAY AS AN INJURY PREVENTION INTERVENTION: DO YELLOW CARD ACCUMULATION POLICIES REDUCE HIGH SCHOOL SOCCER INJURIES?

2020 ◽  
Vol 8 (4_suppl3) ◽  
pp. 2325967120S0022
Author(s):  
Peter K. Kriz ◽  
Jingzhen Yang ◽  
Alan Arakkal ◽  
Timothy Keeley ◽  
R. Dawn Comstock
Keyword(s):  
High School ◽  
Injury Prevention ◽  
Soccer Players ◽  
Fair Play ◽  
Yellow Card ◽  
Time Loss ◽  
Severe Injuries ◽  
Injury Rates ◽  
Illegal Activity ◽  
The Impact

Background: Pediatric sports-related injuries are common, yet prevention efforts too often go unevaluated. Collins et al. studied nine U.S. high school (HS) sports during 2005/06-2006/07, finding boys’ and girls’ soccer had the highest injury rates related to illegal activity. Several states have implemented yellow card accumulation policies (YCPs) in an effort to prevent injuries. Hypothesis/Purpose: Purpose: Evaluate the effectiveness of YCPs in reducing HS soccer competition injuries by comparing injury rates and patterns in states with and without YCPs. Hypotheses: Athlete-athlete contact injury rates are lower in states with YCPs Severe injuries (concussion, fracture, ACL, injury requiring surgery, injury resulting in > 3 weeks’ time loss) are less prevalent in states with YCPs Gender differences influence the effectiveness of YCPs Methods: Retrospective cohort study of NHFS member state association HS soccer players injured during competition in 2005/06-2017/18. Athlete exposure (AEs) and injury data collected from a national sports injury surveillance system, High School RIO. Poisson regression assessed the effects of YCPs on injury rates and patterns. Results: Of 50 NFHS member states associations, high schools from 47 were represented. Overall, 901 athlete-athlete contact injuries occurred during 352,775 competition AEs in states with YCPs and 3,525 during 1,459,708 AEs in states without YCPs. There was no significant difference in overall contact injury rates (rate ratio [RR] 1.06; 95% confidence interval [CI]: 0.98-1.14) between schools in states with and without YCPs. A small, significant increase in overall contact injury rates was discernable after states’ adoption of YCPs (RR 1.17; 95% CI: 1.03, 1.34), particularly in boys’ soccer (RR 1.32; 95% CI 1.08-1.62). A significantly lower proportion of injuries resulting in > 3 weeks’ time loss occurred in states with YCPs (injury proportion ratio [IPR] 0.81; p=0.047), while other severe injuries did not differ. There were no significant differences in YCPs’ effect by gender (p=0.319). Conclusion: Among HS boys’ and girls’ soccer players, playing in states with YCPs did not lower athlete-athlete contact injury rates, although injuries resulting in > 3 weeks’ time loss were less prevalent in states with YCPs. Athlete-athlete contact injury rates were slightly higher in states following adoption of YCPs, particularly in boys’ soccer. Enactment of YCPs alone, without proper enforcement, may not be a sufficient injury prevention strategy. Further studies assessing the impact of HS soccer YCPs need to consider the effects of state level YCP enforcement, documented illegal activity/foul play, and Fair Play education. Tables/Figures: [Table: see text][Table: see text][Table: see text]

scholarly journals Youth Football Injuries: A Prospective Cohort

2017 ◽  
Vol 5 (2) ◽  
pp. 232596711668678 ◽  
Author(s):  
Andrew R. Peterson ◽  
Adam J. Kruse ◽  
Scott M. Meester ◽  
Tyler S. Olson ◽  
Benjamin N. Riedle ◽  
...  
Keyword(s):  
Proportional Hazards ◽  
Injury Rate ◽  
The United States ◽  
Cox Proportional Hazards ◽  
Time Loss ◽  
Level Of Evidence ◽  
Severe Injuries ◽  
Injury Rates ◽  
Youth Football ◽  
Tackle Football

Background: There are approximately 2.8 million youth football players between the ages of 7 and 14 years in the United States. Rates of injury in this population are poorly described. Recent studies have reported injury rates between 2.3% and 30.4% per season and between 8.5 and 43 per 1000 exposures. Hypothesis: Youth flag football has a lower injury rate than youth tackle football. The concussion rates in flag football are lower than in tackle football. Study Design: Cohort study; Level of evidence, 3. Methods: Three large youth (grades 2-7) football leagues with a total of 3794 players were enrolled. Research personnel partnered with the leagues to provide electronic attendance and injury reporting systems. Researchers had access to deidentified player data and injury information. Injury rates for both the tackle and flag leagues were calculated and compared using Poisson regression with a log link. The probability an injury was severe and an injury resulted in a concussion were modeled using logistic regression. For these 2 responses, best subset model selection was performed, and the model with the minimum Akaike information criterion value was chosen as best. Kaplan-Meier curves were examined to compare time loss due to injury for various subgroups of the population. Finally, time loss was modeled using Cox proportional hazards regression models. Results: A total of 46,416 exposures and 128 injuries were reported. The mean age at injury was 10.64 years. The hazard ratio for tackle football (compared with flag football) was 0.45 (95% CI, 0.25-0.80; P = .0065). The rate of severe injuries per exposure for tackle football was 1.1 (95% CI, 0.33-3.4; P = .93) times that of the flag league. The rate for concussions in tackle football per exposure was 0.51 (95% CI, 0.16-1.7; P = .27) times that of the flag league. Conclusion: Injury is more likely to occur in youth flag football than in youth tackle football. Severe injuries and concussions were not significantly different between leagues. Concussion was more likely to occur during games than during practice. Players in the sixth or seventh grade were more likely to suffer a concussion than were younger players.

scholarly journals Hip and groin time-loss injuries decreased slightly but injury burden remained constant in men’s professional football: the 15-year prospective UEFA Elite Club Injury Study

2018 ◽  
Vol 53 (9) ◽  
pp. 539-546 ◽  
Author(s):  
Jonas Werner ◽  
Martin Hägglund ◽  
Jan Ekstrand ◽  
Markus Waldén
Keyword(s):  
Time Trends ◽  
Negative Binomial ◽  
Injury Rate ◽  
Negative Binomial Regression ◽  
Negative Binomial Regression Model ◽  
Professional Football ◽  
Time Loss ◽  
Injury Rates ◽  
Injury Burden ◽  
Groin Injury

BackgroundHip and groin injuries are common in men’s professional football, but the time-trend of these injuries is not known.AimTo investigate hip and groin injury rates, especially time-trends, in men’s professional football over 15 consecutive seasons.Study designProspective cohort study.SettingMen’s professional football.Methods47 European teams were followed prospectively for a varying number of seasons between 2001/2002 and 2015/2016, totalling 268 team seasons. Time-loss injuries and individual player exposure during training and matches were recorded. Injury rate was defined as the number ofinjuries/1000 hours and injury burden as the number oflay-off days/1000 hours. Time-trends for total hip and groin injuries and adductor-related injury rates were analysed using Poisson regression, and injury burden was analysed using a negative binomial regression model.ResultsHip and groin injuries contributed 1812 out of 12 736 injuries (14%), with adductor-related injury as the most common of hip and groin injuries (n=1139, 63%). The rates of hip and groin injury and adductor-related injury were 1.0/1000 hours and 0.6/1000 hours, and these rates decreased significantly with on average 2% (Exp(b)=0.98, 95% CI 0.97 to 0.99, P=0.003) and 3% (Exp(b)=0.97, 95% CI 0.95 to 0.99, P<0.001) per season (year on year), respectively. The seasonal trend of hip and groin injury burden did not improve (Exp(b)=0.99, 95% CI 0.97 to 1.01, P=0.40).ConclusionsHip and groin injuries constitute a considerable part of all time-loss injuries in men’s professional football. Although there was a promising slight decreasing trend in the rates of hip and groin injury (as a category) and adductor-related injury (as a specific diagnosis), the injury burden remained at a consistent level over the study period.

Are Elite Soccer Teams’ Preseason Training Sessions Associated With Fewer In-Season Injuries? A 15-Year Analysis From the Union of European Football Associations (UEFA) Elite Club Injury Study

2020 ◽  
Vol 48 (3) ◽  
pp. 723-729 ◽  
Author(s):  
Jan Ekstrand ◽  
Armin Spreco ◽  
Johann Windt ◽  
Karim M. Khan
Keyword(s):  
Linear Regression ◽  
Regression Models ◽  
Injury Incidence ◽  
Linear Regression Models ◽  
Injury Rates ◽  
Percentage Points ◽  
Competitive Season ◽  
Soccer Teams ◽  
European Football ◽  
Injury Burden

Background: Preseason training develops players’ physical capacities and prepares them for the demands of the competitive season. In rugby, Australian football, and American football, preseason training may protect elite players against in-season injury. However, no study has evaluated this relationship at the team level in elite soccer. Purpose/Hypothesis: The aim of this study was to investigate whether the number of preseason training sessions completed by elite soccer teams was associated with team injury rates and player availability during the competitive season. It was hypothesized that elite soccer teams who participate in more preseason training will sustain fewer injuries during the competitive season. Study Design: Descriptive epidemiology study. Methods: We used the Union of European Football Associations (UEFA) injury dataset to analyze 44 teams for up to 15 seasons (total, 244 team-seasons). Separate linear regression models examined the association between the number of team preseason training sessions and 5 in-season injury measures. Injury-related problems per team were quantified by totals of the following: (1) injury burden, (2) severe injury incidence, (3) training attendance, (4) match availability, and (5) injury incidence. Results: Teams averaged 30 preseason training sessions (range, 10-51). A greater number of preseason training sessions was associated with less injury load during the competitive season in 4 out of 5 injury-related measures. Our linear regression models revealed that for every 10 additional preseason training sessions that the team performed, the in-season injury burden was 22 layoff days lower per 1000 hours ( P = .002), the severe injury incidence was 0.18 severe injuries lower per 1000 hours ( P = .015), the training attendance was 1.4 percentage points greater ( P = .014), and the match availability was 1.0 percentage points greater ( P = .042). As model fits were relatively low (adjusted R2 = 1.3%-3.2%), several factors that contribute to in-season injury outcomes were unaccounted for. Conclusion: Teams that performed a greater number of preseason training sessions had “healthier” in-season periods. Many other factors also contribute to in-season injury rates. Understanding the benefit of preseason training on in-season injury patterns may inform sport teams’ planning and preparation.

scholarly journals Communication quality between the medical team and the head coach/manager is associated with injury burden and player availability in elite football clubs

2018 ◽  
Vol 53 (5) ◽  
pp. 304-308 ◽  
Author(s):  
Jan Ekstrand ◽  
Daniel Lundqvist ◽  
Michael Davison ◽  
Michel D’Hooghe ◽  
Anne Marte Pensgaard
Keyword(s):  
Medical Staff ◽  
Internal Communication ◽  
Medical Team ◽  
Head Coach ◽  
Communication Quality ◽  
Severe Injuries ◽  
Injury Rates ◽  
Football Clubs ◽  
Injury Burden

ObjectivesWe investigated medical staff interpretations and descriptions of internal communication quality in elite football teams to determine whether internal communication was correlated with injuries and/or player availability at training and matches.MethodsMedical staff from 36 elite football clubs across 17 European countries produced 77 reports at four postseason meetings to provide their perceptions of internal communications in their teams. They also recorded data on individual players’ exposure to football and time-loss injuries.ResultsThe injury burden and incidence of severe injuries were significantly higher in teams with low quality of communication between the head coach/manager and the medical team (scores of 1–2 on a 5-point Likert scale) compared with teams with moderate or high-quality scores (scores of 3–5; p=0.008 for both). Teams with low scores had 4%–5% lower training attendance (76% vs 83%, p=0.001) and less availability at matches (82% vs 88%, p=0.004) compared with teams with moderate or high communication quality scores.ConclusionsThe quality of internal communication within a team was correlated with injury rates, training attendance and match availability.

scholarly journals Epidemiology of Elbow Ulnar Collateral Ligament Injuries in Throwing Versus Contact Athletes of the National Collegiate Athletic Association: Analysis of the 2009-2010 to 2013-2014 Seasons

2019 ◽  
Vol 7 (4) ◽  
pp. 232596711983642 ◽  
Author(s):  
Neill Y. Li ◽  
Avi D. Goodman ◽  
Nicholas J. Lemme ◽  
Brett D. Owens
Keyword(s):  
National Collegiate Athletic Association ◽  
Injury Rate ◽  
Ulnar Collateral Ligament ◽  
Surveillance Program ◽  
Collateral Ligament ◽  
Time Loss ◽  
Collegiate Sports ◽  
Severe Injuries ◽  
Injury Rates ◽  
Varsity Sports

Background: The management and outcomes of elbow ulnar collateral ligament (UCL) injuries in throwing athletes have been well investigated. However, less is known regarding the management, severity, and outcomes of such injuries in contact athletes. Purpose: To compare the incidence, severity, and outcomes of elbow UCL injuries between throwing and contact athletes in collegiate sports. Study Design: Descriptive epidemiology study. Methods: Elbow UCL injuries were queried from the National Collegiate Athletic Association (NCAA) Injury Surveillance Program between the seasons of 2009-2010 and 2013-2014 in 25 varsity sports. The rates and distribution of injuries by mechanism, participation restriction time, and outcomes (eg, season-ending injury, surgery) were examined. A severe injury was defined as loss of ≥21 days from participation, a season-ending injury, or requiring a surgical intervention. The injury frequency, incidence per 10,000 athlete-exposures (AEs), and injury proportion ratio comparing throwing and contact athletes were calculated with 95% CIs. Results: Over the course of 5 seasons, 109 UCL injuries were recorded, for an overall injury rate of 0.29 per 10,000 AEs. Of these injuries, 83 (76.1%) were a result of contact and 26 (23.9%) from throwing. Men’s wrestling (1.78 per 10,000 AEs) and men’s baseball (1.12 per 10,000 AEs) sustained the highest injury rates. A larger proportion of throwing (n = 8; 36.4%) compared with contact (n = –7; 9.1%) ( P < 0.01) injuries results in >21 days of time loss. Additionally, more throwing-related UCL injuries required surgery (n = 2; 11.1%) compared with contact-related injuries (n = 1; 1.3%) ( P < 0.01). As a result, throwing athletes demonstrated a significantly higher proportion of severe injuries than contact athletes (injury proportion ratio, 4.62 [95% CI, 1.72-12.40]). Conclusion: The evaluation of athletes in 25 collegiate varsity sports across 5 seasons found over 3 times more elbow UCL injuries in contact versus throwing athletes. However, the number of severe injuries in throwing athletes was significantly higher than in contact athletes. These findings demonstrate that although elbow UCL injuries are prone to occur in both contact and throwing athletes, their prevention, management, and outcomes must be framed on a sport-by-sport basis.

ANALISIS VARIABEL YANG BERPENGARUH TERHADAP KINERJA PERUSAHAAN DI BURSA EFEK INDONESIA

2019 ◽  
Author(s):  
SUSENO - SUSENO
Keyword(s):  
Linear Regression ◽  
Multiple Linear Regression ◽  
Stock Exchange ◽  
T Test ◽  
The Other ◽  
Financial Leverage ◽  
F Test ◽  
Research Results ◽  
Independent Variables ◽  
Influential Variable

ANALISIS VARIABEL YANG BERPENGARUH TERHADAP KINERJA PERUSAHAAN DI BURSA EFEK INDONESIAOleh : Suseno STIE SATRIA Purwokerto ABSTRACT The aims of the research are (1) to analyze influence of age, scale, financial leverage, and profitability to performance of firms at The Indonesian Stock Exchange. (2) to determine the most influential variable on the performance of the firms. Hypotheses proposed in this research were: (1) Age, Scales, Financial Leverage, Profitability influences the performance of firms, (2) Age influences the performance of firms, (3) Scales influences the performance of firms, (4) Financial Leverage influences the performance of firms, (5) Profitability influences the performance of firms. Instrument of analysis employed in the research was multiple linear regression with t test and F test.The results of analyses of t test showed that profitability did not influence the performance of the firms. It was indicated by the value of computed t which was smaller than the value of t table. Meanwhile, the t test of age, scale and financial leverage indicated that the value of computed t &gt; t table. It means that these variables (scale and financial leverage) influenced the performance of the firms. The F test showed that the independent variables of age, scale, financial leverage and profitability as a whole significantly influenced the performance of the firms. It was indicated by the calculated F &gt; the value of F table, the value the age computed t which was smaller than the value of -t table..Based on the research results that age and profitability do not influence the performance of the firms, it is suggested that investors should not pay any attention to those variables. On the other hand, they should pay attention to the variables of scale and financial leverage. It is recommended that for further research should include longer periode of the sample.

scholarly journals Injury rates decreased in men’s professional football: an 18-year prospective cohort study of almost 12 000 injuries sustained during 1.8 million hours of play

2021 ◽  
pp. bjsports-2020-103159
Author(s):  
Jan Ekstrand ◽  
Armin Spreco ◽  
Håkan Bengtsson ◽  
Roald Bahr
Keyword(s):  
Ligament Injury ◽  
Football Players ◽  
Injury Incidence ◽  
Professional Football ◽  
Muscle Injuries ◽  
Time Loss ◽  
Match Play ◽  
Injury Rates ◽  
Surveillance Programme ◽  
Individual Player

BackgroundThe UEFA Elite Club Injury Study is the largest and longest running injury surveillance programme in football.ObjectiveTo analyse the 18-season time trends in injury rates among male professional football players.Methods3302 players comprising 49 teams (19 countries) were followed from 2000–2001 through 2018–2019. Team medical staff recorded individual player exposure and time-loss injuries.ResultsA total of 11 820 time-loss injuries were recorded during 1 784 281 hours of exposure. Injury incidence fell gradually during the 18-year study period, 3% per season for both training injuries (95% CI 1% to 4% decrease, p=0.002) and match injuries (95% CI 2% to 3% decrease, p<0.001). Ligament injury incidence decreased 5% per season during training (95% CI 3% to 7% decrease, p<0.001) and 4% per season during match play (95% CI 3% to 6% decrease, p<0.001), while the rate of muscle injuries remained constant. The incidence of reinjuries decreased by 5% per season during both training (95% CI 2% to 8% decrease, p=0.001) and matches (95% CI 3% to 7% decrease, p<0.001). Squad availability increased by 0.7% per season for training sessions (95% CI 0.5% to 0.8% increase, p<0.001) and 0.2% per season for matches (95% CI 0.1% to 0.3% increase, p=0.001).ConclusionsOver 18 years: (1) injury incidence decreased in training and matches, (2) reinjury rates decreased, and (3) player availability for training and match play increased.

scholarly journals Eye Injuries in High School and Collegiate Athletes

2017 ◽  
Vol 9 (5) ◽  
pp. 444-449 ◽  
Author(s):  
Barry P. Boden ◽  
Lauren A. Pierpoint ◽  
Rebecca G. Boden ◽  
R. Dawn Comstock ◽  
Zachary Y. Kerr
Keyword(s):  
High School ◽  
College Athletes ◽  
Age Groups ◽  
Eye Injury ◽  
Field Hockey ◽  
Eye Injuries ◽  
Time Loss ◽  
Injury Rates ◽  
Men's Basketball ◽  
College Age

Background: Although eye injuries constitute a small percentage of high school and college sports injuries, they have the potential to be permanently debilitating. Hypothesis: Eye injury rates will vary by sport, sex, and between the high school and college age groups. Study Design: Descriptive epidemiology study. Level of Evidence: Level 3. Methods: Data from eye injury reports in high school and college athletes were obtained from the National High School Sports-Related Injury Surveillance System, High School Reporting Information Online (HS RIO) database over a 10-year span (2005-2006 through 2014-2015 school years) and the National Collegiate Athletic Association (NCAA) Injury Surveillance Program (ISP) over an 11-year span (2004-2005 through 2014-2015 school years). Injury rates per 100,000 athlete-exposures (AEs), injury rate ratios (RRs), and 95% CIs were calculated. Distributions of eye injuries by diagnosis, mechanism, time loss, and surgery needs were also examined. Results: A total of 237 and 273 eye injuries were reported in the HS RIO and the NCAA ISP databases, respectively. The sports with the highest eye injury rates (per 100,000 AEs) for combined high school and college athletes were women’s basketball (2.36), women’s field hockey (2.35), men’s basketball (2.31), and men’s wrestling (2.07). Overall eye injury rates at the high school and college levels were 0.68 and 1.84 per 100,000 AEs, respectively. Eye injury rates were higher in competition than practice in high school (RR, 3.47; 95% CI, 2.69-4.48) and college (RR, 3.13; 95% CI, 2.45-3.99). Most injuries were contusions (high school, 35.9%; college, 33.3%) and due to contact (high school, 89.9%; college, 86.4%). Only a small percentage of injuries resulted in time loss over 21 days (high school, 4.2%; college, 3.0%). Conclusion: Eye injury rates and patterns vary by sport, sex, and between the high school and college age groups. Although severe injuries do occur, most eye injuries sustained by high school and college athletes are minor, with limited time loss and full recovery. Clinical Relevance: Additional focus needs to be placed on preventing eye injuries at the collegiate level in women’s and men’s basketball, women’s field hockey, and men’s wrestling.

scholarly journals THE ANALYSIS OF OIL CONTENT IN SEDIMENT AND COMMUNITY STRUCTURE OF MACROZOOBENTHOS IN BELAWAN WATERS OF MEDAN CITY, NORTH SUMATERA PROVINCE

2020 ◽  
Vol 3 (2) ◽  
pp. 167-178
Author(s):  
Doli Juna Setia Tanjung ◽  
Bintal Amin ◽  
Syafruddin Nasution
Keyword(s):  
Community Structure ◽  
Linear Regression ◽  
Oil Content ◽  
Diversity Index ◽  
The Other ◽  
Regression Analyses ◽  
Simple Linear Regression ◽  
Dominance Index ◽  
Ocypode Quadrata ◽  
Evenness Index

This research was conducted in March 2019 to determine the oil content in sediment, it’s community structure of macrozoobenthos and it’s a relationship in Belawan Waters of Medan City, North Sumatera. Four sampling stations with five replications in each station were surveyed. The results showed that the average oil content in sediments exceeded the threshold had set by the National Academy of Science. Macrozoobenthos found consists of Ocypode quadrata, Scyla serrate, Rotun dicauda, Penaeus sp, Murex tribulus, and Nassarius olivaccus. The highest abundance was in Station 3 and the lowest was in Station 2. The diversity index in each station was generally very low. Dominance Index in Station 4 was medium, whilst the other stations were high. Evenness index showed in Station 3 and 4 were in high population, Station 1 was in medium population and Station 2 was in low population. Simple linear regression analyses between oil content in sediment with community structure of macrozoobenthos indicated negative correlation ( Y = 10,5-0,0001x , R2 = 0,0004 and r = 0,02 ) which indicated that the higher the oil content, the lower the macrozoobenthos abundance in sediment.

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