scholarly journals A Preventive Model for Hamstring Injuries in Professional Soccer: Learning Algorithms

2019 ◽  
Vol 40 (05) ◽  
pp. 344-353 ◽  
Author(s):  
Francisco Ayala ◽  
Alejandro López-Valenciano ◽  
Jose Antonio Gámez Martín ◽  
Mark De Ste Croix ◽  
Francisco Vera-Garcia ◽  
...  
Keyword(s):  
Injury Risk ◽  
Factor Model ◽  
Characteristic Curve ◽  
Predictive Ability ◽  
True Positive Rate ◽  
Machine Learning Techniques ◽  
Soccer Players ◽  
True Negative ◽  
Professional Soccer ◽  
Hamstring Injuries

AbstractHamstring strain injury (HSI) is one of the most prevalent and severe injury in professional soccer. The purpose was to analyze and compare the predictive ability of a range of machine learning techniques to select the best performing injury risk factor model to identify professional soccer players at high risk of HSIs. A total of 96 male professional soccer players underwent a pre-season screening evaluation that included a large number of individual, psychological and neuromuscular measurements. Injury surveillance was prospectively employed to capture all the HSI occurring in the 2013/2014 season. There were 18 HSIs. Injury distribution was 55.6% dominant leg and 44.4% non-dominant leg. The model generated by the SmooteBoostM1 technique with a cost-sensitive ADTree as the base classifier reported the best evaluation criteria (area under the receiver operating characteristic curve score=0.837, true positive rate=77.8%, true negative rate=83.8%) and hence was considered the best for predicting HSI. The prediction model showed moderate to high accuracy for identifying professional soccer players at risk of HSI during pre-season screenings. Therefore, the model developed might help coaches, physical trainers and medical practitioners in the decision-making process for injury prevention.

scholarly journals Injuries in Professional Male Soccer Players in the Netherlands: A Prospective Cohort Study

2015 ◽  
Vol 50 (2) ◽  
pp. 211-216 ◽  
Author(s):  
Janine H. Stubbe ◽  
Anne-Marie M. C. van Beijsterveldt ◽  
Sissi van der Knaap ◽  
Jasper Stege ◽  
Evert A. Verhagen ◽  
...  
Keyword(s):  
Cohort Study ◽  
Injury Risk ◽  
Knee Injuries ◽  
Lower Extremities ◽  
Body Part ◽  
Soccer Players ◽  
Injury Incidence ◽  
Time Loss ◽  
Professional Soccer ◽  
Common Diagnosis

Context: Injuries are a major adverse event in a soccer player's career. Reducing injury incidence requires a thorough knowledge of the epidemiology of soccer injuries. Objective: To investigate the incidence and characteristics of injuries in the Dutch premier soccer league. Design: Cohort study. Setting: The Dutch premier soccer league. Patients or Other Participants: During the 2009–2010 soccer season, a total of 217 professional soccer players from 8 teams were prospectively followed. Main Outcome Measure(s): The medical staff recorded time-loss injuries, including information on injuries (ie, type, body part, duration) and exposure data for training sessions and matches. Results: A total of 286 injuries were recorded, affecting 62.7% of the players. The overall injury incidence was 6.2 injuries per 1000 player-hours, 2.8 in training sessions and 32.8 in matches. Most of the recorded injuries were acute (68.5%). Eight percent of the injuries were classified as recurrent. Injuries were most likely to be located in the lower extremities (82.9%). Injury time loss ranged from 1 to 752 days, with a median of 8 days. Knee injuries had the greatest consequences in terms of days of absence from soccer play (on average, 45 days). The most common diagnosis was muscle/tendon injury of the lower extremities (32.9%). Conclusions: Injury risk in the Dutch premier soccer league is high, especially during matches. Preventive measures should focus on the most common diagnoses, namely, muscle/tendon injuries of the lower extremities.

Differences in injury risk and characteristics between Dutch amateur and professional soccer players

2015 ◽  
Vol 18 (2) ◽  
pp. 145-149 ◽  
Author(s):  
A.M.C. (Anne-Marie) van Beijsterveldt ◽  
J.H. Stubbe ◽  
S.L. Schmikli ◽  
I.G.L. van de Port ◽  
F.J.G. Backx
Keyword(s):  
Injury Risk ◽  
Soccer Players ◽  
Professional Soccer

scholarly journals Evaluating injury risk in first and second league professional Portuguese soccer: muscular strength and asymmetry

2016 ◽  
Vol 51 (1) ◽  
pp. 19-26 ◽  
Author(s):  
Alberto Carvalho ◽  
Scott Brown ◽  
Eduardo Abade
Keyword(s):  
Muscle Strength ◽  
Injury Risk ◽  
Dynamic Control ◽  
Peak Torque ◽  
Soccer Players ◽  
Bilateral Asymmetry ◽  
Hamstring Strain ◽  
Professional Soccer ◽  
Maximal Peak ◽  
The Right

AbstractStrength imbalances between the hamstrings and quadriceps are an essential predictor for hamstring strain in soccer. The study aimed to investigate and compare the muscle strength imbalances of professional soccer players of different performance levels. One hundred and fifty nine senior male professional soccer players from first (n = 75) and second league (n = 84) Portuguese clubs participated in this study. Muscle strength was evaluated with a REV9000 isokinetic dynamometer. Maximal peak torque data were used to calculate quadriceps and hamstrings strength during concentric and eccentric actions, bilateral asymmetry, conventional strength ratios and dynamic control ratios. Second league athletes produced slightly lower conventional strength ratios in the right and left legs (ES = 0.22, p = 0.17 and ES = 0.36, p = 0.023, respectively) compared to the first league athletes. No significant differences were found in dynamic control ratios or in bilateral asymmetry among first and second league athletes. These findings do not show a clear link between the competitive level and injury risk in soccer players. However, some of the differences found, particularly in conventional strength ratios, highlight the importance of performing off-season and pre-season strength assessments to prescribe and adjust individual strength training programs among professional soccer players.

scholarly journals Blood Biomarkers Variations across the Pre-Season and Interactions with Training Load: A Study in Professional Soccer Players

2021 ◽  
Vol 10 (23) ◽  
pp. 5576
Author(s):  
Filipe Manuel Clemente ◽  
Francisco Tomás González-Fernández ◽  
Halil Ibrahim Ceylan ◽  
Rui Silva ◽  
Saeid Younesi ◽  
...  
Keyword(s):  
Injury Risk ◽  
Perceived Exertion ◽  
Hematological Parameters ◽  
Blood Parameters ◽  
Training Load ◽  
Soccer Players ◽  
Immune Functions ◽  
Professional Soccer ◽  
Biochemical Analyses ◽  
And Training

Background: Pre-season training in soccer can induce changes in biological markers in the circulation. However, relationships between chosen hematological and biochemical blood parameters and training load have not been measured. Objective: Analyze the blood measures changes and their relationships with training loads changes after pre-season training. Methodology: Twenty-five professional soccer players were assessed by training load measures (derived from rate of perceived exertion- known as RPE) during the pre-season period. Additionally, blood samples were collected for hematological and biochemical analyses. Results: For hematological parameters, significant increases were found for platelets (PLT) (dif: 6.42; p = 0.006; d = −0.36), while significant decreases were found for absolute neutrophils count (ANC) (dif: −3.98; p = 0.006; d = 0.11), and absolute monocytes count (AMC) (dif: −16.98; p = 0.001; d = 0.78) after the pre-season period. For biochemical parameters, there were significant increases in creatinine (dif: 5.15; p = 0.001; d = −0.46), alkaline phosphatase (ALP) (dif: 12.55; p = 0.001; d = −0.84), C-reactive protein (CRP) (dif: 15.15; p = 0.001; d = −0.67), cortisol (dif: 2.85; p = 0.001; d = −0.28), and testosterone (dif: 5.38; p = 0.001; d = −0.52), whereas there were significant decreases in calcium (dif: −1.31; p = 0.007; d =0.49) and calcium corrected (dif: −2.18; p = 0.015; d = 0.82) after the pre-season period. Moreover, the Hooper Index (dif: 13.22; p = 0.01; d = 0.78), and all derived RPE measures increased after pre-season period. Moderate-to-very large positive and negative correlations (r range: 0.50–0.73) were found between the training load and hematological measures percentage of changes. Moderate-to-large positive and negative correlations (r range: 0.50–0.60) were found between training load and biochemical measures percentage of changes. Conclusions: The results indicated heavy physical loads during the pre-season, leading to a decrease in immune functions. Given the significant relationships between blood and training load measures, monitoring hematological and biochemical measures allow coaches to minimize injury risk, overreaching, and overtraining.

scholarly journals Hamstring and Ankle Flexibility Deficits Are Weak Risk Factors for Hamstring Injury in Professional Soccer Players: A Prospective Cohort Study of 438 Players Including 78 Injuries

2018 ◽  
Vol 46 (9) ◽  
pp. 2203-2210 ◽  
Author(s):  
Nicol van Dyk ◽  
Abdulaziz Farooq ◽  
Roald Bahr ◽  
Erik Witvrouw
Keyword(s):  
Risk Factors ◽  
Range Of Motion ◽  
Cox Regression ◽  
Knee Extension ◽  
Ankle Dorsiflexion ◽  
Soccer Players ◽  
Hamstring Injury ◽  
Cox Regression Analysis ◽  
Professional Soccer ◽  
Hamstring Injuries

Background: Hamstring injuries remain a significant injury burden in sports such as soccer that involve high-speed running. It has repeatedly been identified as the most common noncontact injury in elite male soccer, representing 12% of all injuries. As the incidence of hamstring injuries remains high, investigations are aimed at better understanding how to prevent hamstring injuries. Stretching to improve flexibility is commonly used in elite-level sports, but risk factor studies have reported contradicting results, leading to unclear conclusions regarding flexibility as a risk factor for hamstring injuries. Purpose: To investigate the association of lower limb flexibility with the risk of hamstring injuries in professional soccer players. Study Design: Cohort study; Level of evidence, 2. Methods: All teams (n = 18) eligible to compete in the premier soccer league in Qatar (Qatar Stars League [QSL]) underwent a comprehensive musculoskeletal assessment during their annual periodic health evaluation at Aspetar Orthopaedic and Sports Medicine Hospital in Doha, Qatar. Variables included passive knee extension and ankle dorsiflexion range of motion. A clustered multivariate Cox regression analysis was used to identify associations with the risk of hamstring injuries. Receiver operating characteristic (ROC) curves were calculated to determine sensitivity and specificity. Results: A total of 438 unique players (72.4% of all QSL players) competed for 601 player-seasons (148 players competed both seasons) and sustained 78 hamstring injuries. Passive knee extension range of motion (hazard ratio [HR], 0.97 [95% CI, 0.95-0.99]; P = .008) and ankle dorsiflexion range of motion (HR, 0.93 [95% CI, 0.88-0.99]; P = .02) were independently associated with the injury risk. The absolute differences between the injured and uninjured players were 1.8° and 1.4 cm, respectively, with small effect sizes ( d < 0.2). The ROC curve analyses showed an area under the curve of 0.52 for passive knee extension and 0.61 for ankle dorsiflexion, indicating failed to poor combined sensitivity and specificity of the 2 strength variables identified in the multivariate Cox regression analysis. Conclusion: This study identified deficits in passive hamstring and ankle dorsiflexion range of motion as weak risk factors for a hamstring injury. These findings have little clinical value in predicting the risk of future hamstring injuries, and test results must therefore be interpreted cautiously in athletic screening.

scholarly journals Analysis and Mapping of Rainfall-Induced Landslide Susceptibility in A Luoi District, Thua Thien Hue Province, Vietnam

Water ◽  
2018 ◽  
Vol 11 (1) ◽  
pp. 51 ◽  
Author(s):  
Nguyen Long ◽  
Florimond De Smedt
Keyword(s):  
Landslide Susceptibility ◽  
Factor Model ◽  
Characteristic Curve ◽  
False Positive Rate ◽  
Area Under The Curve ◽  
True Positive Rate ◽  
Landslide Susceptibility Mapping ◽  
Certainty Factor ◽  
Validation Test ◽  
Positive Rate

Rainfall-induced landslides form an important natural threat in Vietnam. The purpose of this study is to explore regional landslide susceptibility mapping in the mountainous district of A Luoi in Thua Thien Hue Province, where data on the occurrence and causes of landslides are very limited. Three methods are applied to examine landslide susceptibility: statistical index, logistic regression and certainty factor. Nine causative factors are considered: elevation, slope, geological strata, fault density, geomorphic landforms, weathering crust, land use, distance to rivers and annual precipitation. The reliability of the landslide susceptibility maps is evaluated by a receiver operating characteristic curve and the area under the curve is used to quantify and compare the prediction accuracy of the models. The certainty factor model performs best. This model is optimized by maximizing the difference between the true positive rate and the false positive rate. The optimal model correctly identifies 84% of the observed landslides. The results are verified with a validation test, whereby the model is calibrated with 75% randomly selected observed landslides, while the remaining 25% of the observed landslides are used for validation. The validation test correctly identifies 81% of the observed landslides in the training set and 73% of the observed landslides in the validation set.

Comparisons of new body load and metabolic power average workload indices between starters and non-starters: A full-season study in professional soccer players

2020 ◽  
pp. 175433712097487
Author(s):  
Hadi Nobari ◽  
Gibson Moreira Praça ◽  
Filipe Manuel Clemente ◽  
Jorge Pérez-Gómez ◽  
Jorge Carlos Vivas ◽  
...  
Keyword(s):  
Injury Risk ◽  
Soccer Players ◽  
Metabolic Power ◽  
Early Season ◽  
Professional Soccer ◽  
Weekly Training ◽  
Significant Difference ◽  
Body Load ◽  
Gps Devices ◽  
And Training

The aim of this study was to compare the weekly average training monotony new body load (wTMNBL) and strain (wTSNBL), as well as the weekly average training monotony metabolic power average (wTMMPA) and strain (wTSMPA) between four periods of a season (preseason, early-season, mid-season, and end-season), considering starters and non-starters. Twenty-one professional soccer players (age: 28.27 ± 3.78 years) were monitored throughout a season in the highest level of professional football Premier League in Iran. Data were captured by Global Positioning System (GPS) devices. Independent samples T-tests were applied to analyze the between-group differences for all dependent derived-GPS variables for the full season and its different periods (preseason, early-season, mid-season, and end-season). Based on the amount of time attending in match and training, players were divided into two groups (starters and non-starters) each week. The magnitude of the between-group difference revealed a very large significant greater weekly average TMNBL ( p<0.001, d = −2.42), TSNBL ( p<0.001; d = −2.74), TMMPA ( p<0.001; d =–2.79) and TSMPA ( p<0.001; d = −3.27) for starters when compared to non-starters during the early-season. The findings also revealed a very large significant difference when starters were compared to non-starters during the mid-season (TMNBL: p<0.001, d = −2.89; TSNBL: p<0.001, d = −2.99; TMMPA: p<0.001, d = −3.28; and TSMPA: p<0.001, d = −3.25) and end-season (TMNBL: p<0.001, d = −2.89; TSNBL: p<0.001, d = −3.07; TMMPA: p<0.001, d = −3.16; and TSMPA: p<0.001, d = −3.58). In summary, the results of this study revealed that starters present regularly higher values of NBL, MPA-based weekly training monotony, and training strain than non-starters. This result must be taken into account when planning weekly workloads for these groups. Specifically, starters might experience high values of external workloads because of match-related demands. Therefore, weekly adjustments in their training workload are required to reduce injury risk.

Sign in / Sign up

Export Citation Format

Share Document