Aandagtekort-hiperaktiwiteitsversteuring (ATHV) is een van die deeglikste nagevorste opvoedkundig-sielkundige versteurings. Dit is ook een van die versteurings waarvan die voorkoms drasties vermeerder het oor die laaste drie dekades, met ʼn voorkoms by skoolkinders van 3 tot 17%. Dit kom ook by volwassenes voor. Stimulantmedikasie word algemeen in die behandeling van ATHV voorgeskryf. Ander algemene behandelingsmodaliteite sluit onder andere gedragsterapie, dieët aanpassings en arbeidsterapie in. Oefening as hulpmiddel in die bestuur van ATHV, word goed in die literatuur beskryf, maar word ten spyte hiervan nie algemeen voorgeskryf in die behandeling van ATHV nie. Die primêre doel van die studie was om die rol wat die biokinetikus as oefenkundige te speel het in die bestuur van ATHV, te ondersoek. Die hipotese was dat ATHV-pasiënte wat deelneem aan ʼn oefenprogram onder leiding van ʼn biokinetikus, ʼn verbetering sal toon in akademiese prestasie en gedrag. Die verband tussen ATHV-simptome, aërobiese fiksheid, soepelheid, liggaamsamestelling en balans is ook ondersoek. Deur middel van ʼn meervuldige gevallestudieontwerp is die rol van die biokinetikus in dié verband ondersoek. ʼn Gemengde benadering, met kwantitatiewe sowel as kwalitatiewe elemente, is gebruik ten einde ʼn ryk en omvattende studie te kon doen. Riglyne vir die assessering van ATHV-pasiënte, asook beste oefenpraktyke, is uit die literatuur afgelei. Vyf deelnemers het vir ʼn tydperk van twee tot drie skoolkwartale aan die studie deelgeneem. Die intervensie het bestaan uit ʼn oefenprogram van ongeveer 30 minute per dag, vyf dae per week. Al die deelnemers is vooraf, asook tydens en na die studie getoets aan die hand van die volgende: Liggaamsamestelling, aërobiese fiksheid, soepelheid en balans. Onderhoude met onderwyseresse en ouers, skoolrapporte en vraelyste is verder gebruik om inligting in te samel. Deelnemers het ook narratiewe verslae gelewer oor die belewenis van hulle deelname. Die resultate van hierdie studie het die hipotese ondersteun. Die deelnemers het verbeterings ten opsigte van akademiese prestasie en gedrag getoon. Hulle aërobiese kapasiteit, liggaamsamestelling, soepelheid en balans het ook verbeter en die verband tussen die onderskeie parameters en die ATHVsimptome van elke deelnemer, is aangetoon en individueel bespreek. ʼn Gedeelde sorgooreenkomsmodel is ontwikkel om die rol van die biokinetikus duidelik aan te dui. ʼn Evaluasieprotokol vir gebruik deur biokinetici is ontwikkel en riglyne vir programontwerp vir die ATHV-pasiënt is saamgestel. Die gevolgtrekking van die studie is dat die biokinetikus ʼn besliste rol te speel het in die bestuur van ATHV. / Thesis (PhD)--University of Pretoria, 2013. / gm2014 / Biokinetics, Sport and Leisure Sciences / unrestricted

Hyperlordosis or anterior pelvic tilt is a common non-neutral spinal posture associated with weak core stability, low back pain and altered lumbopelvic muscle activation patterns. Yet the effects of altered lumbopelvic posture and core stability on muscle activation patterns have not been evaluated during a functional movement. The main purpose of this study was to determine the relationship between pelvic tilt, core stability and muscle activation patterns during non-weighted squats in U/19 university-level rugby union players. A total of 49 rugby union players participated in this study. Pelvic tilt (dominant side) was measured from a digital photo with clear reflector markers on the anterior superior iliac spine (ASIS) and posterior superior iliac spine (PSIS) using the Kinovea video analysis software programme (version 0.8.15). Flexibility of the hamstrings, hip flexors and knee extensors was assessed with goniometry. Core stability was assessed using the pressure biofeedback unit and muscle onset times during the ascent phase of non-weighted squats. The onset times of the transverse abdominis (TrA), erector spinae (ES), gluteus maximus (GM) and biceps femoris (BF) muscles were measured using electromyography (EMG). Players were then grouped according to pelvic tilt (anterior and neutral) and by playing position (forwards and backs). The between group differences were evaluated for the abovementioned variables using p-value (statistical significance) and d-value (practical significance) measures. Muscle activation patterns and firing order were determined using descriptive statistics. The mean pelvic tilt of all participants (N=49) was an anterior tilt of 15.35°. When grouped by pelvic tilt, the anterior tilt group showed a mean pelvic tilt of 17.83° (n=27) and the neutral pelvic tilt group showed a mean pelvic tilt of 11.75° (n=22). Despite the differences in pelvic tilt, there was no significant difference in flexibility between the groups. Another controversial result is that the anterior tilt group showed practical significantly better core stability (d=0.54) than the neutral tilt group (46.93° vs 56.3°). During the double leg squat the muscle activation patterns were consistent between the groups. TrA activated first, followed by ES. Thereafter, the BF muscle activated, followed by the GM. The first place activation of TrA is consistent with the literature stating that the deep abdominal stabilisers of individuals with good core stability activate before the movement is initiated. The early onset of muscle activity of ES points to a focus on back extension during the ascent of the squat. Because the pelvic tilt was measured during static standing only, it is unclear whether the players in the neutral tilt group were able to hold the neutral pelvic tilt posture throughout the movement. Research has shown that there is an increased focus on trunk extension during the ascent phase of the squat which is not present during the descent. Future research should focus on assessing the pelvic tilt at the beginning of the ascent phase of the squat to ensure accurate results. The delay in GM activation during the ascent of the squat is concerning. GM acts as a lumbopelvic stabilizer, and its slow activation points to a decrease in lumbopelvic stability. This is very important in weight training, because weight training increases the strain on the lumbar spinal structures, which decreases performance and increases the risk of injury. / MSc (Biokinetics), North-West University, Potchefstroom Campus, 2014

Hyperlordosis or anterior pelvic tilt is a common non-neutral spinal posture associated with weak core stability, low back pain and altered lumbopelvic muscle activation patterns. Yet the effects of altered lumbopelvic posture and core stability on muscle activation patterns have not been evaluated during a functional movement. The main purpose of this study was to determine the relationship between pelvic tilt, core stability and muscle activation patterns during non-weighted squats in U/19 university-level rugby union players. A total of 49 rugby union players participated in this study. Pelvic tilt (dominant side) was measured from a digital photo with clear reflector markers on the anterior superior iliac spine (ASIS) and posterior superior iliac spine (PSIS) using the Kinovea video analysis software programme (version 0.8.15). Flexibility of the hamstrings, hip flexors and knee extensors was assessed with goniometry. Core stability was assessed using the pressure biofeedback unit and muscle onset times during the ascent phase of non-weighted squats. The onset times of the transverse abdominis (TrA), erector spinae (ES), gluteus maximus (GM) and biceps femoris (BF) muscles were measured using electromyography (EMG). Players were then grouped according to pelvic tilt (anterior and neutral) and by playing position (forwards and backs). The between group differences were evaluated for the abovementioned variables using p-value (statistical significance) and d-value (practical significance) measures. Muscle activation patterns and firing order were determined using descriptive statistics. The mean pelvic tilt of all participants (N=49) was an anterior tilt of 15.35°. When grouped by pelvic tilt, the anterior tilt group showed a mean pelvic tilt of 17.83° (n=27) and the neutral pelvic tilt group showed a mean pelvic tilt of 11.75° (n=22). Despite the differences in pelvic tilt, there was no significant difference in flexibility between the groups. Another controversial result is that the anterior tilt group showed practical significantly better core stability (d=0.54) than the neutral tilt group (46.93° vs 56.3°). During the double leg squat the muscle activation patterns were consistent between the groups. TrA activated first, followed by ES. Thereafter, the BF muscle activated, followed by the GM. The first place activation of TrA is consistent with the literature stating that the deep abdominal stabilisers of individuals with good core stability activate before the movement is initiated. The early onset of muscle activity of ES points to a focus on back extension during the ascent of the squat. Because the pelvic tilt was measured during static standing only, it is unclear whether the players in the neutral tilt group were able to hold the neutral pelvic tilt posture throughout the movement. Research has shown that there is an increased focus on trunk extension during the ascent phase of the squat which is not present during the descent. Future research should focus on assessing the pelvic tilt at the beginning of the ascent phase of the squat to ensure accurate results. The delay in GM activation during the ascent of the squat is concerning. GM acts as a lumbopelvic stabilizer, and its slow activation points to a decrease in lumbopelvic stability. This is very important in weight training, because weight training increases the strain on the lumbar spinal structures, which decreases performance and increases the risk of injury. / MSc (Biokinetics), North-West University, Potchefstroom Campus, 2014

In the light of the facts given in literature it is evident that players in the game of netball need to meet specific anthropometric (body length, body mass, percentage body fat and percentage muscle mass), physical (pliancy, abdominal power, aerobic endurance and anaerobic endurance) and motor (speed over 5 m and 10 m, agility and explosive power) requirements. This consequently necessitates specific attention to be given to the mentioned requirements. In spite of the fact that a few studies do exist that enter into the requirements of the profile of netball players in different positions, as well as into what the effect of a periodization programme is on anthropometric, physical and motor requirements, voids do exist regarding the positional profile of 15 to 17 year old netball players and as to what the effect is of a sport specific periodization programme in the course of a season on 15 to 17 year old netball players. In the light of the above–mentioned, this study was undertaken with the aim to: 1) Determine the requirements for 15 to 17 year old netball players; 2) Compile positional profile scales of netball specific requirement for 15 to 17 year old players in the Tlokwe region; 3) Establish the effect of a sport specific periodization programme on anthropometric, physical and motor requirements for 15 to 17 year old female netball players, of a specific school in the Tlokwe region, in the course of a season. 96 players (28 goalkeepers, 44 centre court players and 24 defenders) between ages 15 and 17 years from two high schools in the North–West Province were used in the study to determine positional differences. A group of only 22 player of one school was exposed to a sport specific periodization programme for purposes of the study, since the coach and players from only one school’s teams were prepared to participate in the sport scientific intervention programme for the full duration of the netball season. The afore–mentioned group was evaluated over a period of two years, namely prior to the start of the season (T1), after conclusion of the season once the sport specific periodization programme was completed (T2), prior to the start of the season in the subsequent year (T3) and after conclusion of the season without the sport specific being followed. The data is processed on the basis of descriptive statistics. Furthermore, the practical significance of test result changes between the respective groups and different test sessions were compared using Cohen’s effect size. Literature was consulted to determine whether specific requirements exist for netball players and whether differences occur in the three positional groups. However, no literature could be traced in which only netball specific requirements for 15 to 17 year old players were focused on. The literature did indeed point out clear anthropometric differences between the three positional groups, namely attacking, centre court and defence players in club and elite netball players. The goalkeeper and defence players are, according to literature, considerably taller and heavier than the centre court players. Literature also indicated that differences do indeed occur regarding physical and motor requirements. Centre court players are significantly faster and more agile than the goalkeeper and defenders. However, there were components of which the differences were not prominent concerning the three positional groups. Where a specific positional profile of anthropometric, physical and motor requirements for 15 to 17 year old female netball players was composed from available data of players in the North–West Province, Tlokwe region, the results of the anthropometric requirements indicated that body length showed a large significant difference between the three positional groups, with defenders being the tallest, followed by goalkeepers, and the centre court players being the shortest. Body mass also showed a medium significant difference between goalkeepers and centre court players as well as between centre court players and defence players. Goalkeepers were heavier than centre court players, and defenders also showed a higher body mass than centre court players. The other two variables, namely percentage fat and percentage muscle mass, only showed small practically significant differences, in this group of netball players, between the test sessions. With the physical and motor requirements, results indicated that large practically significant differences occurred in vertical jumping, 5 m speed, 10 m speed and agility between the groups. The general trend observed in the profiles was that the largest significant differences occurred between goalkeepers and defence players on the one hand and centre court players on the other. Vertical jump and speed showed a large significant difference between goalkeepers and centre court players as well as between centre court players and defenders, although the goalkeepers and defenders’ results corresponded considerably. Other large significant differences occurred in the 10 m speed as well as in 505–agility to the left between centre court players and defenders. In summary it can be mentioned that the most and the largest significant differences occurred between goalkeepers and centre court players as well as between defenders and centre court players. Only one medium significant difference occurred between the goalkeepers and defenders, which is ankle dorsiflexion and which can be ascribed to injuries. From this it can be inferred that a positional profile can indeed be compiled for the different positional groups in netball, but that the requirements of positional variables between goalkeepers and defenders correspond largely and that the large difference between the last–mentioned two groups occur when compared with those of the centre court players of this specific group. The results of the group of twenty–two players that were evaluated twice during the course of both netball seasons indicate that the variable that showed a large significant difference between T1 and T2, following the sport specific periodization program, was body mass (inverted difference). Although there was no large significant difference, it can clearly be deduced from the graphs presented in the study that a visible difference (improvement) was observed in most of the variables. The variables that showed a large practically significant difference with the training of the coach’s general programme, were ankle dorsiflexion on the left, abdominal power and 5 m speed (inverted effect). A number of variables indeed existed that also showed medium and small significant differences during the course of both seasons, but it will not be mentioned here. A number of shortcomings and recommendations did indeed come to the fore during and after the course of the study. It should, however, be borne in mind that such a structured periodization programme is very important for the development of netball potential. / Thesis (Ph.D. (Human Movement Science))--North-West University, Potchefstroom Campus, 2011.

In the light of the facts given in literature it is evident that players in the game of netball need to meet specific anthropometric (body length, body mass, percentage body fat and percentage muscle mass), physical (pliancy, abdominal power, aerobic endurance and anaerobic endurance) and motor (speed over 5 m and 10 m, agility and explosive power) requirements. This consequently necessitates specific attention to be given to the mentioned requirements. In spite of the fact that a few studies do exist that enter into the requirements of the profile of netball players in different positions, as well as into what the effect of a periodization programme is on anthropometric, physical and motor requirements, voids do exist regarding the positional profile of 15 to 17 year old netball players and as to what the effect is of a sport specific periodization programme in the course of a season on 15 to 17 year old netball players. In the light of the above–mentioned, this study was undertaken with the aim to: 1) Determine the requirements for 15 to 17 year old netball players; 2) Compile positional profile scales of netball specific requirement for 15 to 17 year old players in the Tlokwe region; 3) Establish the effect of a sport specific periodization programme on anthropometric, physical and motor requirements for 15 to 17 year old female netball players, of a specific school in the Tlokwe region, in the course of a season. 96 players (28 goalkeepers, 44 centre court players and 24 defenders) between ages 15 and 17 years from two high schools in the North–West Province were used in the study to determine positional differences. A group of only 22 player of one school was exposed to a sport specific periodization programme for purposes of the study, since the coach and players from only one school’s teams were prepared to participate in the sport scientific intervention programme for the full duration of the netball season. The afore–mentioned group was evaluated over a period of two years, namely prior to the start of the season (T1), after conclusion of the season once the sport specific periodization programme was completed (T2), prior to the start of the season in the subsequent year (T3) and after conclusion of the season without the sport specific being followed. The data is processed on the basis of descriptive statistics. Furthermore, the practical significance of test result changes between the respective groups and different test sessions were compared using Cohen’s effect size. Literature was consulted to determine whether specific requirements exist for netball players and whether differences occur in the three positional groups. However, no literature could be traced in which only netball specific requirements for 15 to 17 year old players were focused on. The literature did indeed point out clear anthropometric differences between the three positional groups, namely attacking, centre court and defence players in club and elite netball players. The goalkeeper and defence players are, according to literature, considerably taller and heavier than the centre court players. Literature also indicated that differences do indeed occur regarding physical and motor requirements. Centre court players are significantly faster and more agile than the goalkeeper and defenders. However, there were components of which the differences were not prominent concerning the three positional groups. Where a specific positional profile of anthropometric, physical and motor requirements for 15 to 17 year old female netball players was composed from available data of players in the North–West Province, Tlokwe region, the results of the anthropometric requirements indicated that body length showed a large significant difference between the three positional groups, with defenders being the tallest, followed by goalkeepers, and the centre court players being the shortest. Body mass also showed a medium significant difference between goalkeepers and centre court players as well as between centre court players and defence players. Goalkeepers were heavier than centre court players, and defenders also showed a higher body mass than centre court players. The other two variables, namely percentage fat and percentage muscle mass, only showed small practically significant differences, in this group of netball players, between the test sessions. With the physical and motor requirements, results indicated that large practically significant differences occurred in vertical jumping, 5 m speed, 10 m speed and agility between the groups. The general trend observed in the profiles was that the largest significant differences occurred between goalkeepers and defence players on the one hand and centre court players on the other. Vertical jump and speed showed a large significant difference between goalkeepers and centre court players as well as between centre court players and defenders, although the goalkeepers and defenders’ results corresponded considerably. Other large significant differences occurred in the 10 m speed as well as in 505–agility to the left between centre court players and defenders. In summary it can be mentioned that the most and the largest significant differences occurred between goalkeepers and centre court players as well as between defenders and centre court players. Only one medium significant difference occurred between the goalkeepers and defenders, which is ankle dorsiflexion and which can be ascribed to injuries. From this it can be inferred that a positional profile can indeed be compiled for the different positional groups in netball, but that the requirements of positional variables between goalkeepers and defenders correspond largely and that the large difference between the last–mentioned two groups occur when compared with those of the centre court players of this specific group. The results of the group of twenty–two players that were evaluated twice during the course of both netball seasons indicate that the variable that showed a large significant difference between T1 and T2, following the sport specific periodization program, was body mass (inverted difference). Although there was no large significant difference, it can clearly be deduced from the graphs presented in the study that a visible difference (improvement) was observed in most of the variables. The variables that showed a large practically significant difference with the training of the coach’s general programme, were ankle dorsiflexion on the left, abdominal power and 5 m speed (inverted effect). A number of variables indeed existed that also showed medium and small significant differences during the course of both seasons, but it will not be mentioned here. A number of shortcomings and recommendations did indeed come to the fore during and after the course of the study. It should, however, be borne in mind that such a structured periodization programme is very important for the development of netball potential. / Thesis (Ph.D. (Human Movement Science))--North-West University, Potchefstroom Campus, 2011.