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Application of teaching-coaching methodology to the level of a vocational school.McGrath, Edward J. 01 January 1951 (has links) (PDF)
No description available.
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A Pure Space To Be Mexican: Ethnic Mexicans And The Mexico-u.S. Soccer Rivalry, 1990-2002Rodriguez, Paola 01 January 2008 (has links)
This thesis examines the soccer rivalry between Mexico and the United States that has been evolving since the early 1990s. Neither Mexico nor the United States are soccer powerhouse nations, yet their rivalry is arguably one of the most passionate contests in the world. For the Mexican National team the rivalry has become a struggle to maintain dominance and power in one of the few arenas where Mexico traditionally has had an advantage. The ability of the United States to challenge Mexican hegemony has intensified the rivalry. Although the United States has been able to score some victories inside the field, acceptance in their home venues has been elusive. When playing against Mexico, even as the host team, the United States is consistently treated as the visiting team by the ethnic Mexicans living in the United States who compose the majority of the spectators. The rivalry has increased as a result of ethnic Mexicans' overt preference for the Mexican National team. In the U.S. public sphere, ethnic Mexicans have been segregated, discriminated against, economically marginalized and considered invisible. Outside of the stadium, ethnic Mexicans in general have been sidelined by U.S. society. Inside the stadium, they have made their presence known and have become highly visible. By chanting for the Mexican team, wearing the colors of El Tri, and carrying the Mexican flag, the fans have asserted their identity and heritage.
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A history of professional association football in England during the Second World War /Schleppi, John Ross January 1972 (has links)
No description available.
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Effects of Sports Drinks on the performance of Young Soccer PlayersStewart, Kimberly C. 26 June 2001 (has links)
This study examined the effects of a sports drink on the performance of young soccer players. Ten competitive young male soccer players, ages 10 and 11, performed two experimental trials while consuming 32 ounces of either a sports drink (G)- Gatorade or a placebo (P)- Crystal Light in a double-blind, crossover design. Both trials consisted of a 15-minute warm-up period, a pre and post exercise test protocol and a 40-minute indoor scrimmage with a five-minute half time. The assigned fluid was consumed just prior to the warm-up, pre-test protocol, scrimmage and post-test protocol as well as during the half time of the scrimmage. The exercise tests included six activities such as shooting velocity, dribbling, passing, jumping, backward running, and sprinting in order to measure skill, agility, power, and speed. The results showed that due to the interaction of the 40-minute scrimmage and the consumption of Gatorade, the post-test shot velocity measurement was significantly (p<0.01) lower for P while G remained similar to the pre-test measurement. Also, there was a significant (p<0.05) decrease in the number of jumps completed for both P and G during the post-test jumping exercise when compared to the pre-test measurement. However, there were no significant difference of treatment, time and/or their interaction for the dribbling, passing, backward running, and sprinting. Many possible reasons may account for this lack of effect. 1) Muscle glycogen may not have been substantially depleted, possibly because the prescribed exercise during the trial was not intense or long enough. 2) Prior to the experimental trials, muscle glycogen stores were sufficient where no additional CHO was necessary (due to the subject's diet on the day of the trial or the short fast prior to the experimental trials). 3) Alternative mechanism, such as increased lactate production or dehydration and not muscle glycogen depletion, may be the cause of impaired skills. 4) A child's increased fat utilization allows for less of a need for manipulation of glycogen stores. / Master of Science
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Design of a Soccer StadiumClayton, David Michael 10 October 2007 (has links)
Resisting external forces can be a source of beauty. This work represents an effort to understand how architecture can be derived from the struggle against natural forces to create a built-form. Starting with an idea, that of a tensile roof, the design of a soccer stadium developed into what is presented here. / Master of Architecture
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Description des caractéristiques des situations d'apprentissage et de perfectionnement tactiques au soccer et au hockey sur glace.Poulin Beaulieu, Ian 27 January 2024 (has links)
Le développement des performances des joueurs en sports collectifs d'invasion de territoire est une tâche complexe qui ne peut se faire qu'en jouant des matchs. C'est principalement grâce aux Situations d'Apprentissage et de Perfectionnement (SAP) pendant les périodes d'entrainement que les entraineurs offrent des activités visant le développement des principales composantes de la performance des joueurs (physique, technique, stratégique, tactique). Parmi toutes ces composantes, la tactique demeure un élément particulièrement difficile à faire apprendre car ces actions doivent continuellement s'adapter en fonction de celles des coéquipiers et adversaires. Or, la littérature scientifique offre peu d'informations sur la manière d'analyser les SAP en sport compétitif, et aucune étude récente décrit clairement la proportion de temps ou d'activités accordée aux apprentissages tactiques qui sont à la base de ces sports collectifs. Ce projet vise d'abord à créer et valider une procédure de catégorisation des SAP permettant de décrire et de comparer les activités offertes pendant les séances d'entrainement. Ensuite, l'étude vise à décrire les caractéristiques des SAP et exercices offerts aux athlètes de hockey sur glace et de soccer afin de quantifier et qualifier le temps passé au développement des habiletés tactiques. L'analyse de contenus de séances (n=29 au hockey et n=34 au soccer) a permis de créer un Arbre décisionnel comprenant une série de questions permettant de catégoriser toutes formes de SAP offertes aux joueurs de sports collectifs. À partir de cette catégorisation, une description détaillée des SAP offertes aux joueurs est illustrée. Les résultats indiquent que les aspects tactiques sont peu entrainés en générale, bien que des différences importantes existent entre les équipes observées. Les conclusions observées démontrent que la proportion ou la qualité des SAP tactiques est faible comparativement aux autres SAP et peu cohérente avec les fondements de ces sports. / Little information is available regarding how to categorize Learning Activities (LA) proposed to athletes during training sessions in competitive team sport. Due to the importance of game fundamentals in team sports, teaching tactical skills should predominate all other components of player performance (physical, technical, strategic, tactical). However, observation of coaches' training sessions seems to show that coaches use few tactical SAPs compared to technical or physical conditioning activities. The purpose of this study was to create a categorization framework that would allow the description and comparison of the characteristics of SAPs offered to athletes in ice hockey and soccer in competitive teams. Analysis of practice sessions (N = 29 in ice hockey and N = 34 in soccer) made it possible to create a Decision Tree comprising of a series of questions that enables the categorization of all forms of SAPs proposed to team sport athletes. This framework was then used to analyze 421 SAPs used by coaches in these two sports. Results of the analysis showed that the proportion or quality of tactical exercises were low compared to technical skills SAPs or physical conditioning exercises. In conclusion, the Decision tree makes it possible to categorize most learning situations or exercises offered to athletes. In addition, the results demonstrate the importance of new pedagogical strategies allowing a better development of tactical skills.
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A prediction model for the prevention of soccer injuries amongst youth players / J.H. Serfontein.Serfontein, Johannes Hendrik January 2009 (has links)
Background: Football (Soccer) is arguably the most popular sport in the international sporting arena. A survey conducted by FIFA (Fédération International de Football Association) (FCPA, 2000) indicated that there are 240 million people who regularly play soccer around the world. Internationally, there are 300 000 clubs with approximately 1.5 million teams. In South Africa, there were 1.8 million registered soccer players in 2002/2003 (Alegi, 2004). Although youth players are predominantly amateurs and have no financial value for their clubs or schools, their continued health and safety are still of vital importance. There are some clubs which contract development players at 19 years of age in preparation for playing in their senior sides and these young players should be well looked after, to ensure a long career playing soccer. Being able to predict injuries and prevent them would be of great value to the soccer playing community.
Aims: The main aim of this research was to create a statistical predictive equation
combining biomechanics, balance and proprioception, plyometric strength ratios of ND/Bil (Non dominant leg plyometrics/ Bilateral plyometrics), D/Bil (Dominant leg plyometrics/ Bilateral plyometrics) and ND+D/Bil (Non dominant leg + dominant leg plyometrics/ Bilateral plyometrics) and previous injuries to determine a youth soccer player's risk of the occurrence of lower extremity injuries. In the process of reaching this aim it was necessary to record an epidemiological profile of youth soccer injuries over a two season period. It was also necessary to record a physical profile of, and draw comparisons between, school and club youth soccer players. Following the creation of the prediction model a preventative training programme was created for youth soccer players, addressing physical shortcomings identified with the model.
Design: A prospective cohort study
Subjects: Schoolboy players from two schools in the North West Province, as well as club players from three age groups were used for this study. Players from the U/16 and U/18 teams in the two schools were tested prior to the 2007 season. Players from the U/17, U/18 and U/19 club development teams were tested prior to the 2008 season. The combined total number of players in the teams amounted to 110 players.
Method: The test battery consisted of a biomechanical evaluation, proprioceptive and plyometric testing and an injury history questionnaire. The Biomechanical evaluation was done according to the protocol compiled by Hattingh (2003). This evaluation was divided into five regions with a dysfunction score being given for each region. A single limb stance test was used to test proprioception. A Sergeant jump test was utilised using the wall mark method to test plyometric jumping height. A previous injury questionnaire was also completed on all players prior to testing. Test subjects from the schools were tested with the test battery prior to commencement of the 2007 season. The testing on the club teams was undertaken prior to the 2008 season. Injuries were recorded on the prescribed injury recording form by qualified Physiotherapists at weekly sports injury clinics at each of the involved schools and clubs. The coaching staff monitored exposure to training activities and match play on the prescribed recording forms. These training and match exposure hours were used, along with the recorded injuries for creating an epidemiological profile. Injuries were expressed as the amount of injuries per 1000 play hours. Logistical regression was done by using the test battery variables as independent variables and the variable injured/not injured as dependent variable (Statsoft, 2003). This analysis created prediction functions, determining which variables predict group membership of injured and non injured players.
Results: There were 110 youth players involved in the research study from seven teams and four different age groups. There were two groups of U/16 players, an U/17 group, three U/18 groups and an U/19 group. The players were involved in a total of 7974 hours of exposure to training and match play during the seasons they were monitored. The average age of the players was 16.6 years. The majority of players were right limb dominant (83.6%) and 65.7% of players failed a single limb stance test. The mean jump height for both legs combined was 33.77cm, with mean heights of 22.60cm for dominant leg jump and 22.66cm for the non dominant leg. In the biomechanical evaluation of the lower leg and foot area, the average youth player presented with adaptation of toes, normal or flat medial foot arches, a normal or pronated rear foot in standing and lying and a normal or hypomobile mid-foot joint. Between 42.7% and 51.8% of players also presenting with decreased Achilles tendon suppleness and callusing of the transverse foot arch.
The youth profile for the knee area indicated that the players presented with excessive tightness of the quadriceps muscles, normal patella tilt and squint, normal knee height, a normal Q-angle, a normal VMO: VL ratio and no previous injuries. This profile indicated very little dysfunction amongst youth players for the knee area. For the hip area, the youth profile was described as follows: There was shortening of hip external rotators, decreased Gluteal muscles length, normal hip internal rotation and no previous history of injury. Between 38.2% and 62.7% of players also exhibit shortened muscle length of the adductor and Iliopsoas muscles and decreased length of the ITB (Iliotibial Band).
In the Lumbo-pelvic area there was an excessive anterior tilt of the pelvis with normal lumbar extension, side flexion, rotation and lumbar saggital view without presence of scoliosis. Between 58.18% and 65.45% of players presented with an abnormal coronal view and decreased lumbar flexion. Between 41.81% and 44.54% of players also presented with leg length, ASIS, PSIS, Cleft, Rami and sacral rhythm asymmetry. The similarity of the results for these tests in all players contributed to a new variable called 'SIJ dysfunction'. This was compiled from the average of the scores for Leg length, ASIS, PSIS, Cleft, Rami and Sacral rhythm, which was also considered for inclusion in the prediction model.
The neurodynamic results of youth players indicated that approximately between 44.54% and 50.91% of players presented with decreased Straight leg raise and prone knee bend tests. The total combined dysfunction scores for the left and right sides were 17.091 and 17.909 respectively, indicating that there were higher levels of dysfunction on the right side than the left. This increased unilateral dysfunction could probably be attributed to limb dominance and increased use of the one leg for kicking and passing during the game.
In the epidemiological study on youth players, there were a total of 49 training injuries and 52 match injuries. The total injury rate for youth players was 12.27 injuries/1000 hours, with a total match injury rate of 37.12 injuries/1000 match hours. The combined training injury rate was 7.17 injuries/1000 training hours. 87.13% of injuries were of the lower limb area and the individual areas with the highest percentage of injuries were the Ankle (25.74%), Knee (19.80%), Thigh (15.84%) and Lower leg (14.85%).The totals for youth players indicated that sprains (30.69% of total), strains (27.72% of total) and contusions (27.72% of total) were the most common causative mechanism of injuries. The severity of injuries show 'zero day' (no time off play) injuries to be the most common type (35.64%), followed by 'slight' (1 to 3 days off play) (33.66%) and 'minor' (4 to 7 days off play) (14.85%). School players had higher injury rates than club players but the severity of injuries to club players was higher, with longer absences from play. Non-contact injuries accounted for 52.47% of the total with 46.53% being contact injuries. School players had lower levels of non-contact injuries than club players, which correlated well with lower dysfunction scores recorded for school players during the biomechanical evaluations. This demonstrated that there was a definite relationship between levels of biomechanical dysfunction and the percentage of non-contact injuries in youth players, which formed the premise of the creation of a prediction model for non-contact youth soccer injuries.
The next step in the creation of a prediction model was to identify the variables that discriminated maximally between injured and non-injured players. This was done using stepwise logistic regression analysis. After the analysis, ten variables with the largest odds ratios were selected for inclusion in the prediction model to predict non-contact injuries in youth soccer players. The prediction model created from the stepwise analysis presented as follows:
P (injury)=
exp(-8.2483 -1.2993a + 1.8418b + 0.2485c + 4.2850d + 1.3845e + 1.3004f-1.1566g + 1.8273h-0.9460i-0.5193j) l + exp(-8.2483-1.2993a + 1.8418b+ 0.2485c + 4.2850d + 1.3845e + 1.3004f-1.1566g + 1.8273h-0.94601-0.5193J)
a = Toe dysfunction
b = Previous ankle injury
c = Ankle dysfunction
d = SIJ dysfunction
e = Lumbar Extension
f = Straight Leg Raise
g = Psoas length
h = Patella squint
i = Gluteal muscle length
j = Lumbar dysfunction
P = probability of non contact injury
exp(x) = e x , with e the constant 2.7183
In the ankle area, the toe positional test, previous ankle injury history and combined ankle dysfunction score were included in the prediction model. In the knee area, the patella squint test was included in the model. In the hip area, the Psoas component of the Thomas test was included, along with the Gluteal muscle length test. In the Lumbo-pelvic area, the SIJ dysfunction (average of Leg length, ASIS, PSIS, Rami, Cleft and Sacral rhythm tests), lumbar extension test and lumbar dysfunction scores were included in the prediction model. In the neurodynamic area, the Straight leg raise test was included in the prediction model. The prediction model therefore contained tests from all five the bio mechanical areas of the body. Overall, this model correctly predicted 86.91% of players as either injured or not-injured. The I value (effect size index for improvement over chance) of the prediction model (1=0.67), along with the sensitivity (65.52%), specificity (94.87%), overall correct percentage of prediction (86.91%) and Hosmer and Lemeshow interferential goodness-to-fit value (X 2(8) = 0.7204), all demonstrated this prediction model to be a valid and accurate prediction tool for non-contact youth soccer injuries
A second prediction model, for the prediction of hip and groin injuries amongst youth players, was also created. The prediction model created from the stepwise analysis for groin injuries presents as follows:
P (Groin injury)^
exp(-116.2 + 33.5383d + 14.5108k + 4.1972m + 1.9330e + 10.7006f-14.4028n + 48.8751p) l + exp(-116.2 + 33.5383d+14.5108k + 4.1972m + 1.9330e + 10.7006f-14.4028n + 48.8751p)
d = SIJ dysfunction
k = Previous knee injury
m = Previous hip injury
e = Lumbar extension
f = Straight leg raise
n = Limb dominance
p = ND/Bil plyometric ratio
P = probability of groin injury
exp(x) = ex, with e the constant 2.7183
The prediction model for hip and groin injuries included the variables of SIJ dysfunction, previous knee injury, previous hip injury, lumbar extension, straight leg raise, limb dominance and the ratio of non-dominant leg to bilateral legs plyometric height. When all the validifying tests were examined, the I-value (0.64868), sensitivity (66.67%), specificity (98.01%), false negatives (1.98%), false positives (33.33%), Hosmer and Lemeshow goodness-to-fit value (X2(8) = 0.77) and the overall percentage of correct prediction (96.26%) all reflected that this model was an accurate prediction tool for hip and groin injuries amongst youth soccer players.
Conclusion: This study showed that it was possible to create a prediction model for non-contact youth soccer injuries based on a pre-season biomechanical, plyometric and proprioceptive evaluation along with a previous injury history questionnaire. This model appears as follows:
P (injury)=
exp(-8.2483 -1.2993a + 1.8418b + 0.2485c + 4.2850d + 1.3845e + 1.3004f - 1.1566g + 1.8273h - 0.9460i - 0.5193J)
l + exp(-8.2483-1.2993a+ 1.8418b + 0.2485c + 4.2850d + 1.3845e + 1.3004f-1.1566g+1.8273h-0.94601-0.5193J)
a = Toe dysfunction b=Previous ankle injury c = Ankle dysfunction d= SIJ dysfunction e=Lumbar Extension
f = Straight Leg Raise
g = Psoas length
h = Patella squint
i = Gluteal muscle length
j = Lumbar dysfunction
P = probability of non contact injury
exp(x) = ex, with e the constant 2.7183
It was also possible to create a prediction model for non contact hip and groin injuries, which
appears as follows:
P (Groin injury)=
exp(-116.2 + 33.5383d + 14.5108k + 4.1972m + 1.9330e + 10.7006f-14.4028n + 48.8751p) l + exp(-116.2 + 33.5383d + 14.5108k + 4.1972m + 1.9330e + 10.7006f-14.4028n + 48.8751p)
d = SIJ dysfunction
k = Previous knee injury
m = Previous hip injury
e = Lumbar extension
f = Straight leg raise
n = Limb dominance
p = ND/Bil plyo metric ratio
P = probability of groin injury
exp(x) = ex, with e the constant 2.7183
It was also possible to create a prediction model for non contact hip and groin injuries, which appears as follows:
P (Groin injury)=
exp(-116.2 + 33.5383d + 14.5108k + 4.1972m + 1.9330e + 10.7006f-14.4028n + 48.8751p) l + exp(-116.2 + 33.5383d + 14.5108k + 4.1972m + 1.9330e + 10.7006f-14.4028n + 48.8751p)
d = SIJ dysfunction
k = Previous knee injury
m = Previous hip injury
e = Lumbar extension
f = Straight leg raise
n = Limb dominance
p = ND/Bil plyo metric ratio
P = probability of groin injury
exp(x) = ex, with e the constant 2.7183
Using the hip and groin prediction model, combined with the injury prediction model, injuries in youth soccer players can be predicted. The data for each player should first be substituted into the injury prediction model, to determine the chance of getting injured during the season. The data should then be substituted into the hip and groin injury prediction model, determining the chance of hip and groin injuries during the season. The results from the groin injury prediction model could then be used to exclude groin injuries amongst players. A negative result for the hip and groin injury, which showed a false negative percentage of 1.98%, could be used to determine that an injury that was predicted using the overall injury prediction model, would not be a hip and groin injury. A positive result in the groin injury test could, however, not exclude injuries to other body areas that were predicted by the overall injury prediction model, so the groin injury prediction model could only be used to exclude hip and groin injuries. / Thesis (Ph.D. (Education)--North-West University, Potchefstroom Campus, 2009.
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A prediction model for the prevention of soccer injuries amongst youth players / J.H. Serfontein.Serfontein, Johannes Hendrik January 2009 (has links)
Background: Football (Soccer) is arguably the most popular sport in the international sporting arena. A survey conducted by FIFA (Fédération International de Football Association) (FCPA, 2000) indicated that there are 240 million people who regularly play soccer around the world. Internationally, there are 300 000 clubs with approximately 1.5 million teams. In South Africa, there were 1.8 million registered soccer players in 2002/2003 (Alegi, 2004). Although youth players are predominantly amateurs and have no financial value for their clubs or schools, their continued health and safety are still of vital importance. There are some clubs which contract development players at 19 years of age in preparation for playing in their senior sides and these young players should be well looked after, to ensure a long career playing soccer. Being able to predict injuries and prevent them would be of great value to the soccer playing community.
Aims: The main aim of this research was to create a statistical predictive equation
combining biomechanics, balance and proprioception, plyometric strength ratios of ND/Bil (Non dominant leg plyometrics/ Bilateral plyometrics), D/Bil (Dominant leg plyometrics/ Bilateral plyometrics) and ND+D/Bil (Non dominant leg + dominant leg plyometrics/ Bilateral plyometrics) and previous injuries to determine a youth soccer player's risk of the occurrence of lower extremity injuries. In the process of reaching this aim it was necessary to record an epidemiological profile of youth soccer injuries over a two season period. It was also necessary to record a physical profile of, and draw comparisons between, school and club youth soccer players. Following the creation of the prediction model a preventative training programme was created for youth soccer players, addressing physical shortcomings identified with the model.
Design: A prospective cohort study
Subjects: Schoolboy players from two schools in the North West Province, as well as club players from three age groups were used for this study. Players from the U/16 and U/18 teams in the two schools were tested prior to the 2007 season. Players from the U/17, U/18 and U/19 club development teams were tested prior to the 2008 season. The combined total number of players in the teams amounted to 110 players.
Method: The test battery consisted of a biomechanical evaluation, proprioceptive and plyometric testing and an injury history questionnaire. The Biomechanical evaluation was done according to the protocol compiled by Hattingh (2003). This evaluation was divided into five regions with a dysfunction score being given for each region. A single limb stance test was used to test proprioception. A Sergeant jump test was utilised using the wall mark method to test plyometric jumping height. A previous injury questionnaire was also completed on all players prior to testing. Test subjects from the schools were tested with the test battery prior to commencement of the 2007 season. The testing on the club teams was undertaken prior to the 2008 season. Injuries were recorded on the prescribed injury recording form by qualified Physiotherapists at weekly sports injury clinics at each of the involved schools and clubs. The coaching staff monitored exposure to training activities and match play on the prescribed recording forms. These training and match exposure hours were used, along with the recorded injuries for creating an epidemiological profile. Injuries were expressed as the amount of injuries per 1000 play hours. Logistical regression was done by using the test battery variables as independent variables and the variable injured/not injured as dependent variable (Statsoft, 2003). This analysis created prediction functions, determining which variables predict group membership of injured and non injured players.
Results: There were 110 youth players involved in the research study from seven teams and four different age groups. There were two groups of U/16 players, an U/17 group, three U/18 groups and an U/19 group. The players were involved in a total of 7974 hours of exposure to training and match play during the seasons they were monitored. The average age of the players was 16.6 years. The majority of players were right limb dominant (83.6%) and 65.7% of players failed a single limb stance test. The mean jump height for both legs combined was 33.77cm, with mean heights of 22.60cm for dominant leg jump and 22.66cm for the non dominant leg. In the biomechanical evaluation of the lower leg and foot area, the average youth player presented with adaptation of toes, normal or flat medial foot arches, a normal or pronated rear foot in standing and lying and a normal or hypomobile mid-foot joint. Between 42.7% and 51.8% of players also presenting with decreased Achilles tendon suppleness and callusing of the transverse foot arch.
The youth profile for the knee area indicated that the players presented with excessive tightness of the quadriceps muscles, normal patella tilt and squint, normal knee height, a normal Q-angle, a normal VMO: VL ratio and no previous injuries. This profile indicated very little dysfunction amongst youth players for the knee area. For the hip area, the youth profile was described as follows: There was shortening of hip external rotators, decreased Gluteal muscles length, normal hip internal rotation and no previous history of injury. Between 38.2% and 62.7% of players also exhibit shortened muscle length of the adductor and Iliopsoas muscles and decreased length of the ITB (Iliotibial Band).
In the Lumbo-pelvic area there was an excessive anterior tilt of the pelvis with normal lumbar extension, side flexion, rotation and lumbar saggital view without presence of scoliosis. Between 58.18% and 65.45% of players presented with an abnormal coronal view and decreased lumbar flexion. Between 41.81% and 44.54% of players also presented with leg length, ASIS, PSIS, Cleft, Rami and sacral rhythm asymmetry. The similarity of the results for these tests in all players contributed to a new variable called 'SIJ dysfunction'. This was compiled from the average of the scores for Leg length, ASIS, PSIS, Cleft, Rami and Sacral rhythm, which was also considered for inclusion in the prediction model.
The neurodynamic results of youth players indicated that approximately between 44.54% and 50.91% of players presented with decreased Straight leg raise and prone knee bend tests. The total combined dysfunction scores for the left and right sides were 17.091 and 17.909 respectively, indicating that there were higher levels of dysfunction on the right side than the left. This increased unilateral dysfunction could probably be attributed to limb dominance and increased use of the one leg for kicking and passing during the game.
In the epidemiological study on youth players, there were a total of 49 training injuries and 52 match injuries. The total injury rate for youth players was 12.27 injuries/1000 hours, with a total match injury rate of 37.12 injuries/1000 match hours. The combined training injury rate was 7.17 injuries/1000 training hours. 87.13% of injuries were of the lower limb area and the individual areas with the highest percentage of injuries were the Ankle (25.74%), Knee (19.80%), Thigh (15.84%) and Lower leg (14.85%).The totals for youth players indicated that sprains (30.69% of total), strains (27.72% of total) and contusions (27.72% of total) were the most common causative mechanism of injuries. The severity of injuries show 'zero day' (no time off play) injuries to be the most common type (35.64%), followed by 'slight' (1 to 3 days off play) (33.66%) and 'minor' (4 to 7 days off play) (14.85%). School players had higher injury rates than club players but the severity of injuries to club players was higher, with longer absences from play. Non-contact injuries accounted for 52.47% of the total with 46.53% being contact injuries. School players had lower levels of non-contact injuries than club players, which correlated well with lower dysfunction scores recorded for school players during the biomechanical evaluations. This demonstrated that there was a definite relationship between levels of biomechanical dysfunction and the percentage of non-contact injuries in youth players, which formed the premise of the creation of a prediction model for non-contact youth soccer injuries.
The next step in the creation of a prediction model was to identify the variables that discriminated maximally between injured and non-injured players. This was done using stepwise logistic regression analysis. After the analysis, ten variables with the largest odds ratios were selected for inclusion in the prediction model to predict non-contact injuries in youth soccer players. The prediction model created from the stepwise analysis presented as follows:
P (injury)=
exp(-8.2483 -1.2993a + 1.8418b + 0.2485c + 4.2850d + 1.3845e + 1.3004f-1.1566g + 1.8273h-0.9460i-0.5193j) l + exp(-8.2483-1.2993a + 1.8418b+ 0.2485c + 4.2850d + 1.3845e + 1.3004f-1.1566g + 1.8273h-0.94601-0.5193J)
a = Toe dysfunction
b = Previous ankle injury
c = Ankle dysfunction
d = SIJ dysfunction
e = Lumbar Extension
f = Straight Leg Raise
g = Psoas length
h = Patella squint
i = Gluteal muscle length
j = Lumbar dysfunction
P = probability of non contact injury
exp(x) = e x , with e the constant 2.7183
In the ankle area, the toe positional test, previous ankle injury history and combined ankle dysfunction score were included in the prediction model. In the knee area, the patella squint test was included in the model. In the hip area, the Psoas component of the Thomas test was included, along with the Gluteal muscle length test. In the Lumbo-pelvic area, the SIJ dysfunction (average of Leg length, ASIS, PSIS, Rami, Cleft and Sacral rhythm tests), lumbar extension test and lumbar dysfunction scores were included in the prediction model. In the neurodynamic area, the Straight leg raise test was included in the prediction model. The prediction model therefore contained tests from all five the bio mechanical areas of the body. Overall, this model correctly predicted 86.91% of players as either injured or not-injured. The I value (effect size index for improvement over chance) of the prediction model (1=0.67), along with the sensitivity (65.52%), specificity (94.87%), overall correct percentage of prediction (86.91%) and Hosmer and Lemeshow interferential goodness-to-fit value (X 2(8) = 0.7204), all demonstrated this prediction model to be a valid and accurate prediction tool for non-contact youth soccer injuries
A second prediction model, for the prediction of hip and groin injuries amongst youth players, was also created. The prediction model created from the stepwise analysis for groin injuries presents as follows:
P (Groin injury)^
exp(-116.2 + 33.5383d + 14.5108k + 4.1972m + 1.9330e + 10.7006f-14.4028n + 48.8751p) l + exp(-116.2 + 33.5383d+14.5108k + 4.1972m + 1.9330e + 10.7006f-14.4028n + 48.8751p)
d = SIJ dysfunction
k = Previous knee injury
m = Previous hip injury
e = Lumbar extension
f = Straight leg raise
n = Limb dominance
p = ND/Bil plyometric ratio
P = probability of groin injury
exp(x) = ex, with e the constant 2.7183
The prediction model for hip and groin injuries included the variables of SIJ dysfunction, previous knee injury, previous hip injury, lumbar extension, straight leg raise, limb dominance and the ratio of non-dominant leg to bilateral legs plyometric height. When all the validifying tests were examined, the I-value (0.64868), sensitivity (66.67%), specificity (98.01%), false negatives (1.98%), false positives (33.33%), Hosmer and Lemeshow goodness-to-fit value (X2(8) = 0.77) and the overall percentage of correct prediction (96.26%) all reflected that this model was an accurate prediction tool for hip and groin injuries amongst youth soccer players.
Conclusion: This study showed that it was possible to create a prediction model for non-contact youth soccer injuries based on a pre-season biomechanical, plyometric and proprioceptive evaluation along with a previous injury history questionnaire. This model appears as follows:
P (injury)=
exp(-8.2483 -1.2993a + 1.8418b + 0.2485c + 4.2850d + 1.3845e + 1.3004f - 1.1566g + 1.8273h - 0.9460i - 0.5193J)
l + exp(-8.2483-1.2993a+ 1.8418b + 0.2485c + 4.2850d + 1.3845e + 1.3004f-1.1566g+1.8273h-0.94601-0.5193J)
a = Toe dysfunction b=Previous ankle injury c = Ankle dysfunction d= SIJ dysfunction e=Lumbar Extension
f = Straight Leg Raise
g = Psoas length
h = Patella squint
i = Gluteal muscle length
j = Lumbar dysfunction
P = probability of non contact injury
exp(x) = ex, with e the constant 2.7183
It was also possible to create a prediction model for non contact hip and groin injuries, which
appears as follows:
P (Groin injury)=
exp(-116.2 + 33.5383d + 14.5108k + 4.1972m + 1.9330e + 10.7006f-14.4028n + 48.8751p) l + exp(-116.2 + 33.5383d + 14.5108k + 4.1972m + 1.9330e + 10.7006f-14.4028n + 48.8751p)
d = SIJ dysfunction
k = Previous knee injury
m = Previous hip injury
e = Lumbar extension
f = Straight leg raise
n = Limb dominance
p = ND/Bil plyo metric ratio
P = probability of groin injury
exp(x) = ex, with e the constant 2.7183
It was also possible to create a prediction model for non contact hip and groin injuries, which appears as follows:
P (Groin injury)=
exp(-116.2 + 33.5383d + 14.5108k + 4.1972m + 1.9330e + 10.7006f-14.4028n + 48.8751p) l + exp(-116.2 + 33.5383d + 14.5108k + 4.1972m + 1.9330e + 10.7006f-14.4028n + 48.8751p)
d = SIJ dysfunction
k = Previous knee injury
m = Previous hip injury
e = Lumbar extension
f = Straight leg raise
n = Limb dominance
p = ND/Bil plyo metric ratio
P = probability of groin injury
exp(x) = ex, with e the constant 2.7183
Using the hip and groin prediction model, combined with the injury prediction model, injuries in youth soccer players can be predicted. The data for each player should first be substituted into the injury prediction model, to determine the chance of getting injured during the season. The data should then be substituted into the hip and groin injury prediction model, determining the chance of hip and groin injuries during the season. The results from the groin injury prediction model could then be used to exclude groin injuries amongst players. A negative result for the hip and groin injury, which showed a false negative percentage of 1.98%, could be used to determine that an injury that was predicted using the overall injury prediction model, would not be a hip and groin injury. A positive result in the groin injury test could, however, not exclude injuries to other body areas that were predicted by the overall injury prediction model, so the groin injury prediction model could only be used to exclude hip and groin injuries. / Thesis (Ph.D. (Education)--North-West University, Potchefstroom Campus, 2009.
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Soccer and the American DreamLawrence, Ian January 2009 (has links)
The American Dream is founded upon the ideological belief that ‘you can be anything you want to be, regardless of your current class position.’ This belief is contained within the dominant prevailing notion that the U.S. is a meritocracy where power and success are associated with determination and failure with laziness. This thesis challenges whether the American Dream is a relevant, attainable and viable concept for higher education students via the avenue of a soccer scholarship. In so doing, the research presented challenges the perceived wisdom of ‘American exceptionalism’ from a critical theoretical perspective. The research question at the heart of this study is ‘what are the motives of American university students for undertaking a soccer scholarship?’ The adoption of an interpretive paradigm for this study aims to provide an explanation of student decision-making. In the final analysis, this approach reveals what soccer means to the lives of the student-athletes. The central themes of the study were established via a pilot study and categorised as: family, social class, social mobility and career development. Questionnaires were completed by 154 students from two separate Division One universities. Twelve students were then purposively sampled and interviewed using a semi-structured format. To supplement these opinions, interviews were then conducted with a selection of coaches and athletic directors at the respective institutions. Analysis of the responses was contextualised using the framework provided by Csikszentmihayli and Schneider’s (2000) ‘Support/Challenge Questionnaire’. The findings support a common hypothesis that the family is a significant agent in socialising of their children to the cultural values of the American Dream. The findings additionally reveal support for the notion that families are important influences on their child’s sport mobility orientations in the soccer context. An alternative explanation proposed here is that the transmission process is actually a two-way dialogue in which children socialised their parents and vice versa. The family in this study represent a potentially problematic social process for the inculcation of values related to the maintenance of social life. The conclusions presented clearly reveal that the majority of students embarking on a soccer scholarship are motivated by the need to firstly finance their higher education and secondly to take part in a sport they have played since childhood. Students were aware of the uncertainty of the marketplace and the limitations of their own technical ability. As such their participation in the scholarship could be considered to be a pragmatic adaptation of a ‘labour of love.’
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Assessment of the acute sensorimotor and neurocognitive effects of repeated heading of a soccer ballArthur-Banning, Skye 01 November 2002 (has links)
Several recent studies have revealed that high caliber European professional
soccer players often have diminished levels of neurological functioning, yet no study has
been able to identify the specific aspect of soccer participation responsible for these
decreases. In an effort to identify a source of mild traumatic brain injury present in
everyday participation in soccer, this study investigated whether a single bout of heading
a soccer ball would have acute detrimental, measurable effects on sensorimotor and
neurocognitive functioning. We hypothesized that subjects would exhibit significant
changes in postural stability, memory, and concentration immediately after an acute bout
of repeated heading a soccer ball. Additionally, we evaluated the protective effect(s)
associated with wearing a mouthguard while performing the acute bout of heading.
Twenty-eight elite level soccer players (mean age, 20.9 �� 2.5 yrs) were randomly
assigned to one of three experimental groups: Headers with mouthguard (n=10),
Headers with no mouthguard (n=10), and Control (n=8). Subjects in the two treatment
groups performed 12 headers of soccer balls projected at 40 km/hr from an electric soccer
ball-launching machine. Postural stability was evaluated using a Biodex Stability
System, while memory and concentration were assessed using Wechsler Digit Span
(WDS) tests (digits forward and digits backward) in a 3 x 2 factorial ANOVA design (��=0.05). There were no significant main effects or interactions among the three measures
of postural stability scores in the three groups (p>0.05). The WDS Forward group
means ranged from 10.4 �� 1.8 to 13.5 �� 1.2 while the WDS Backward means ranged
from 6.4 �� 1.1 to 7.7 �� 3.0, but were not different among the groups (p>0.05). We
concluded that a single bout of 12 soccer headers approximating the number of headers
performed during a typical NCAA Division I-A soccer practice did not produce
significant deficits in postural stability, memory, or concentration. While our findings
are similar to several recent studies, we suggest that more sensitive measurement tools
such as ImPACT neurocognitive testing and functional magnetic resonance imaging be
utilized to determine the effects of acute as well as chronic exposure to headers in soccer
players. / Graduation date: 2003
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