Thesis (MScPhysio)--Stellenbosch University, 2014. / ENGLISH ABSTRACT: Introduction: Groin injuries are among the top six injuries in contact sports and may lead to career ending chronic pain. Research on the role of knee kinematics in developing chronic groin pain in sport is scarce. Objective: The purpose of this study was to determine if there are differences in knee kinematics during a single-leg drop-landing in sports participants with chronic groin pain compared to asymptomatic controls. Methodology: A descriptive study was conducted. Twenty active sports’ participants were recruited from soccer and rugby clubs situated around the Cape Peninsula area, Western Cape, South Africa. The three-dimensional (3D) knee kinematics of ten cases with chronic groin pain and ten asymptomatic controls was analysed. Knee kinematics was analysed in the FNB-3D Vicon Laboratory at Stellenbosch University, using an eight camera Vicon system. A positive adductor squeeze test was used as a diagnostic test to include cases with chronic groin pain. Each participant performed six single-leg drop landings. The main outcome measure was 3D knee kinematics at initial foot contact and at the lowest vertical position of the drop landing. The following sub-groups were analysed: seven unilateral groin pain cases compared to their seven matched controls; three bilateral groin pain cases where their most painful leg and least painful leg were compared to their matched controls, respectively. Descriptive statistical techniques were used for all outcome measures; means and standard deviations (SD) were calculated, followed by a Student’s t-test to determine significant differences between the cases and controls. For all outcomes with p-values equal to or below 0.05, the effect size was calculated using the Cohen’s D. Results: The findings of this study indicated a significant difference (p=0.0001) between cases with unilateral groin pain having less knee internal rotation compared to the controls at the lowest vertical position of the drop landing in the transverse plane. Significantly less internal rotation (p<0.0001), was also noted in the cases with bilateral groin pain (in the most painful leg and the less painful leg), although this was noted at foot contact. Cases with bilateral groin pain also had significantly (p<0.001) more knee varus (adduction) during the landing phase. Conclusion: Differences in knee kinematics between sports participants with chronic groin pain and asymptomatic controls were found. These findings imply that the knee joint should be included during assessment and rehabilitation of individuals suffering with chronic groin pain. Due to the cross-sectional study design of the current study, it cannot be stated for certain whether the knee kinematics noted in the groin pain group are causative or as a result of groin pain. Future prospective studies are thus recommended; these studies should focus on the effect of contralateral knee kinematics on the hip adductors and may include exploration of the muscular components during a single-leg drop landing. / AFRIKAANSE OPSOMMING: Inleiding: Lies beserings is een van die top ses beserings in kontak sport en kan lei tot chroniese lies pyn en selfs die be-eindigging van ‘n sportloopbaan. Navorsing oor die rol van knie kinematika in die ontwikkeling van chroniese liesbeserings in sport is skaars. Doelwit: Die doel van hierdie studie was om te bepaal of daar verskille in die knie kinematika is tydens 'n enkel been val landing in sport deelnemers met chroniese lies pyn in vergelyking met gesonde kontroles. Metode: 'n Beskrywende studie was uitgevoer. Twintig aktiewe sport deelnemers is gewerf van rugby en sokker sportklubs geleë rondom die Kaapse Skiereiland, Wes-Kaap, Suid-Afrika. Die 3D knie kinematika van tien gevalle met chroniese lies pyn en tien asimptomatiese bypassende kontroles is ontleed. Knie kinematika was ontleed in die FNB-3D Vicon Laboratorium by die Universiteit van Stellenbosch, met behulp van 'n agt-kamera Vicon stelsel. 'n Positiewe Adduktor druk toets was gebruik as 'n diagnostiese toets om gevalle met chroniese lies pyn in te sluit. Om die knie kinematika te analiseer, het elke deelnemer ses enkel been val landings uitgevoer . Die belangrikste uitkomsmeting was 3D knie kinematika by die aanvanklike voet kontak en by die laagste vertikale posisie van die enkel-been val landing. Die volgende sub-groepe was ontleed: sewe unilaterale lies pyn gevalle in vergelyking met hul sewe bypassende kontroles; drie bilaterale lies pyn gevalle waar hul mees pynlike been, sowel as minder pynlike been onderskeidelik vergelyk was met hul bypassende kontroles. Beskrywende statistiese tegnieke was gebruik vir alle uitkoms maatreëls; gemiddeldes en standaardafwykings (SA) was bereken, gevolg deur 'n Studente’s t-toets om beduidende verskille tussen die gevalle en kontroles te bepaal. Vir al die uitkomste met p-waardes gelyk of onder 0.05, is die effekgrootte bereken deur die Cohen’s D. Resultate: Die bevindings van hierdie studie dui op 'n beduidende verskil (p=0,0001) tussen gevalle met unilaterale lies pyn met minder interne knie rotasie in vergelyking met die kontroles by die laagste vertikale posisie van die val landing in die dwars vlak. Aansienlik minder interne rotasie (p<0,0001), is ook opgemerk in gevalle met bilaterale lies pyn (in die mees pynlike been en die minder pynlik been), alhoewel tydens voet kontak. Gevalle met bilaterale lies pyn het ook betekenisvol (p <0.001) meer knie varus (adduksie) tydens die landingsfase gehad. Gevolgtrekking: Verskille bestaan in die knie kinematika tussen sport deelnemers met chroniese liesbesering pyn en gesonde kontroles. Hierdie bevindinge impliseer dat die knie behoort ingesluit te word tydens die assessering en rehabilitasie van individue met chroniese lies pyn. As gevolg van die deursnee-studie ontwerp van hierdie studie, kan dit nie bevestig word of die knie kinematika die oorsaak van die chroniese pyn is nie. Toekomstige voornemende studies word dus aanbeveel, hierdie studies moet fokus op die effek van die kinematika van die kontralaterale knie op die heup adduktore en kan moontlik die ondersoek van die spier kinetika tydens hierdie aktiwiteit insluit.

The purpose of this project is to review current literature on the mechanics and physiology of the vertical jump and to provide an understanding of the jump itself. The second purpose is to develop a step by step program to increase vertical jump from grade school through high school.

Thesis (MScPhysio)--Stellenbosch University, 2014. / ENGLISH ABSTRACT: Introduction-Groin injuries are among the top six most cited injuries in soccer and account for 10-18 per cent of all injuries reported in contact sport. Groin pain can result from a variety of pathologies, but according to literature, 63 per cent of groin pain is due to adductor pathology. Objective-The objective of this study was to explore if there are kinematic differences in the hip joint in sports participants with groin pain compared to matched healthy controls. Study design A cross sectional, descriptive study was conducted. Study setting-The study was conducted at the FNB -3D motion analysis laboratory at the University of Stellenbosch, South Africa. Outcome variables-The dependent variables included hip kinematics in the sagittal, frontal and transverse planes at foot strike, lowest vertical point of the pelvis and total range of hip motion during a single leg drop landing. Methodology-The study sample comprised 20 male club level soccer-and, rugby players, running and cycling participants between the ages of 18-55 years of age. Ten of the subjects had chronic groin pain and the other ten were healthy matched controls. An eight-camera Vicon system was used to analyse the kinematics of the hip joint during single leg drop landing. For the purpose of comparison, the data was analysed for participants with unilateral groin pain and matched controls (n=14) and participants with bilateral groin pain and controls (n=6). The full set of data was subdivided for analysis into three distinct sub-groups. Unilaterally injured groin cases (n=7) were matched with seven healthy controls for analysis. Bilaterally injured groin cases (n=3) were matched with three healthy controls. Results-Cases with unilateral groin pain at initial contact had significantly more abduction of the hip joint when compared to controls (p<0.05). The effect size of this difference was large (0.94). Cases with unilateral groin pain also demonstrated greater hip internal rotation while the controls had external rotation (p<0.05) during a drop landing activity. Bilaterally injured groin cases landed with significantly (p=?) greater ranges of hip flexion as well as in significantly (p=?) more hip abduction during a drop landing activity. They also demonstrated greater total range of motion in the frontal plan when compared to controls. Groin pain cases overall demonstrated greater ranges of motion and tended to land in more abduction compared to controls. Conclusion-This study found that during a single leg drop landing, sports participants with unilateral chronic groin pain landed with significantly greater hip abduction and exhibited larger total range of motion in the transverse plane, which may indicate impaired stability of the hip complex when compared to controls. / AFRIKAANSE OPSOMMING: Inleiding-Liesbeserings is een van die top ses mees prominente sokker beserings. Dit beloop 10-18 persent van alle beserings wat in kontaksport aangemeld word. Liespyn kan die gevolg wees van ‘n verskeidenheid patologië, maar volgens die literatuur is 63 persent van liespyn as gevolg adduktor patologie. Doelwitte-Die doelwit van hierdie studie was om ondersoek in te stel of daar enige kinematiese veranderinge in die heupgewrig is in spelers met liespyn in vergelyking met dieselfde vergelykbare spelers sonder liespyn. Studie Ontwerp-‘n Deursnit, beskrywende studie was onderneem. Studie Omgewing-Die studie was uitgevoer by die FNB-3D bewegingsanalise laboratorium van die Stellenbosch Universiteit, Suid-Afrika. Uitkomsveranderlikes-Die afhanklike veranderlikes het in gesluit die heup kinematika in die sagitale, frontale en transvers vlakke met voet kontak endie laagste vertikale punt van die pelvis sowel as die totale heup omvang van beweging gedurende een been landing. Metodologie-Die studie populasie het bestaan uit 20 manlike sokker- en, rugbyspelers, hardlopers en fietsryers tussen die ouderdomme van 18 en 55 jaar. Tien van die deelnemers het kroniese liespyn gehad en die ander tien in die gelyke gesonde groep was sonder liespyn. Die agt kamera Vicon sisteem was gebruik om die kinematika van die heupgewrig te analseer tydens een been landing. Vir die doel om ‘n vergelyking te kan maak, was die data geanaliseer van deelnemers met unilaterale liespyn en die vergelykende groep sonder liespyn (n=14) en deelnemers met bilaterale liespyn en hulle vergelykende groep sonder liespyn (n=6).. Die volledige stel data was onderverdeel in drie afsonderlike sub groepe. Vir die analiese was unilaterale liesbeserings (n=7) vergelyk met sewe deelnemers sonder liespyn in die kontrolegroep. Deelnemers met bilaterale liesbeserings (n=3) was vergelyk met drie in die kontrolegroep. Resultate-Die deelnemers met unilaterale liespyn het met eerste kontak beduidend meer abduksie van die heupgewrig gehad in vergelyking met die kontrolegroep (p<0.05). Die effek van hierdie verskil was groot (0.94). Die deelnemers met unilaterale liespyn het ook ‘n grooter interne rotasie getoon, terwyl die kontrole groep meer eksterne rotasie gedemonstreer het (p<0.05) met landing. Deelnemers met bilaterale liespyn het beduidend (p=?) meer heup fleksie en abduksie omvang van beweging tydens landing. Hulle het ook ‘n groter totale heup omvang van beweging in die frontale vlak gehad in vergelyking met die kontrolegroep. Deelnemers met liespyn het oor die algemeen ‘n grooter omvang van beweging getoon, en was geneig om met meer abduksie van die heup te land as die kontrolegroep. Gevolgtrekking-Die studie toon dat deelnemers met kroniese unilaterale liespyn, tydens een been landing, beduidende meerheup abduksie toon en dat die heup in die transverse vlak meer totale omvang van beweging gebruik wat kan dui op onstabiliteit in die heupkompleks in vergelyking met die kontrolegroep.

The purpose of this study was to investigate two different plyometric training techniques for increasing vertical jumping ability. Twenty-four female high school volleyball players were matched for height and weight and distributed equally among three groups. Each subject performed a vertical jump test, Margaria power test, Wingate bicycle test, and an isokinetic leg strength test prior to and following six weeks of training. Plyometric training significantly (p<.05) improved vertical jumping ability and some indices of leg strength and power. Weighted plyometrics did not enhance performance more than plyometrics alone. These data support the view that plyometric training with or without added weights enhances vertical jumping and leg power.