Masters Degrees (Exercise, Sport and Lifestyle Medicine)

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    Attitudes, behaviours and learning resources of amateur rugby union coaches and players towards the ruck event during training and match play
    (Stellenbosch : Stellenbosch University, 2024-03 ) Brooks, Michael; Kraak, Wilbur Julio; Parmar, Nimai; Stellenbosch University. Faculty of Medical and Health Sciences. Dept. of Exercise, Sport and Lifestyle Medication.
    ENGLISH ABSTRACT: Rugby union, commonly known as rugby, is a dynamic and physically demanding team sport with a rich history and a global following. It boasts over 9.2 million players and captivates the hearts of more than 344 million avid fans worldwide. One of the key elements in rugby is the ruck event, a critical phase of play where players on their feet compete for the ball while it's on the ground. This involves players from both teams making contact over the ball, trying to gain possession. Success in managing the ruck can sway the outcome of a match, enabling teams to shift momentum and exert dominance over their opponents. Hence, the ruck event emerges as an area of utmost importance for players, coaches, and referees. In this context, the attitudes, behaviours, and learning resources of amateur rugby coaches and players concerning the ruck event become pivotal factors influencing the sport's development and success. Understanding how these individuals perceive and engage with the ruck holds interest for key rugby stakeholders and carries implications for the field of rugby coaching and player development. This study investigates the attitudes, behaviours, and learning resources of amateur rugby coaches and players in South Africa, with a specific focus on the ruck event. Recognising the pivotal role of rucks in rugby, a sport marked by its physicality and strategic complexity, the study offers crucial insights into coaching methodologies, player development, and injury prevention strategies. The first aim of the study was to adapt an existing questionnaire by Hendricks et al. (2012 & 2020) that focused on the tackle event to fit the focus of the current study. The second aim was to assess the validity and reliability of the adapted questionnaire measuring the attitudes, behaviours, and learning resources of amateur rugby coaches and players towards the ruck event. The third aim was to administer the adapted questionnaire that measured the attitudes, behaviours, and learning resources of South African amateur rugby coaches and players towards the ruck event in rugby. This thesis follows a research article format with the first research article addressing the first and second aim of the study. This part of the study was pivotal, focusing on the adaptation, validation, and reliability testing of the questionnaire. This process involved an extensive literature review, discussions with rugby experts, and a rigorous validation and reliability process, including an expert panel review and test-retest of the questionnaire for reliability purposes. The questionnaire's high Intraclass Correlation Coefficient (ICC) scores, 0.88 for coaches and 0.71 for players, confirmed its reliability. Research article two addressed the third aim of the study, presenting key results and discussions. The study revealed that 75% of predominantly male coaches (99%) emphasized the importance of mastering proper ruck techniques, crucial both for winning possession (78% of coaches) and preventing injuries (81% of coaches). Coaches reported dedicating significant time to training ruck skills, with a focus on body positioning (53% of coaches) and decision-making (73% of coaches). A statistical significance in coaches’ role regarding the intensity of off-season training (p = 0.04), preference for live rucking in a 2 vs. 2 grid (p < 0.01), and a focus on footwork before the ruck (p = 0.02) was seen. Significant differences were also identified in the preferred learning choices of World Rugby Level 3 coaches compared to coaches with other qualifications (p = 0.04). World Rugby Level 3 coaches exhibited a preference for workshops, coaching clinics, interaction with other coaches, and individual demonstrations. In contrast, coaches with other qualifications (p = 0.02) leaned towards learning through media channels, including social media platforms. Coaches also placed strong emphasis on continuous learning and adapting coaching strategies, relying on one-on-one verbal instruction (83%) and digital media resources, such as the internet (74%), televised matches (69%), and sports shows (78%). Research article three addressed the third aim of the study, providing insights from players, with 78% identifying the ruck as a vital game component. Players emphasized mastering ruck techniques for a competitive edge (86% of players) and injury prevention (80% of players). A statistically significant finding found that the more experienced players exhibited a preference for 10 or more sessions (p = 0.04) in the off-season compared to the inexperienced players. Their preferred learning methods included one-on-one verbal instruction (88% of players) and self-reflection (90% of players), showing a strong inclination towards visual and experiential learning, like reviewing video footage of matches (91% of players) and participating in on-field demonstrations (98% of players). Another statistically significant finding was that the more experienced players exhibited a preference for full-contact practice matches (p = 0.05) for injury prevention and improving ruck performance to inexperienced players. The more experienced players also showed a preference for “Driving and not diving into the ruck” (p = 0.03) during training rucking technique compared to the inexperienced players. In conclusion, this study enriches rugby research, especially at the amateur level in South Africa, providing a comprehensive understanding of the dynamics of the ruck event, with significant implications for coaching practices and player development. It offers invaluable perspectives for enhancing coaching methods, player performance and safety, and fostering a deeper appreciation of rugby's complexities.
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    Exploring the perceptions of coaches regarding coach-athlete relationships when coaching Generation Z South African academy level rugby union players
    (Stellenbosch : Stellenbosch University, 2024-03) Landman, Marc Derek; Kraak, Wilbur Julio; Grobbelaar, Heinrich; Stellenbosch University. Faculty of Medical and Health Sciences. Dept. of Exercise, Sport and Lifestyle Medication.
    ENGLISH ABSTRACT: The coach-athlete relationship is not a mere by-product of the coaching process but serves as its very foundation (Jowett, 2005). Coaches and athletes share an interdependent relationship that connects them on emotional, cognitive, and behavioural levels (Jowett & Ntoumanis, 2004). To effectively coach athletes and cultivate strong coach-athlete relationships, coaches must understand their athletes, including their character, their strengths, and weaknesses. In today's landscape, adapting coaching approaches to align with an understanding of the athletes' characteristics is more crucial than ever before. Coaches now face the challenge of navigating a new generation of athletes, commonly referred to as Generation Z or Gen Z (Francis, 2018). Born between 1995 and 2012, these individuals have grown up in a digital age, shaping their character and behaviour (Rosen, 2010; Seemiller & Grace, 2016; Gould et al., 2020). The purpose of this study is to gain a comprehensive understanding of the coach-athlete relationships with Gen Z academy level rugby players in the South African context. Drawing upon the research by Jowett (2005) and Gould et al. (2020), this study aimed to explore the perceptions of coaches regarding coach-athlete relationships, the factors that influence the coach-athlete relationship and will unpack the process of building healthy relationships from the coach's perspective. To achieve this, a qualitative research approach was utilised, capturing the subjective experiences and perspectives of the coaches through interviews. The 11 participants who agreed to be interviewed are highly trained or national level coaches with more than six years of experience at academy level rugby. The information collection process consisted of one-on-one semi-structured over Microsoft-Teams. The interview script was derived from the Coach-Athlete Relationship Questionnaire (CART-Q) and in the 11 interviews, there was saturation of the elicited information. To analyse the information, Merriam and Tisdell’s (2016) six-step process of analysis was followed. Six main themes arose from the analysis. Theme one described the coaches' perspectives on working with Gen Z athletes. This theme was split up into three sub-themes, the characteristics of Gen Z which the coaches perceived facilitated their development and those characteristics which debilitated their development, and lastly the effects of the COVID-19 pandemic on the player’s development. Theme two looked at the first C in Jowett’s 3+1C’s model, which was a Closeness between coaches and athletes. This theme was split up into five themes that the coaches perceived closeness to cover: Loving and caring, getting closer, trusting, respecting, and not respecting some players. The third theme covered Commitment between both coaches and athletes. Commitment was broken into three sub-themes, committing personally, committing towards the team and sacrifices that were made. The fourth theme was the third C, Complementarity, this theme covered the sub-themes of goal setting and collectively working towards a common goal. The fifth theme and final C of the 3+1C’s was Co-orientation. The coaches perceived communication and how each party views their relationship with each other were important and became the two sub-themes. The sixth theme was the process of developing the coach-athlete relationship from the coaches' perspectives. This was broken down into the sub-themes of how the coaches can mentally approach developing the coach-athlete relationship and how they can practically build the coachathlete relationship. To conclude, all facets of the coach-athlete relationship are interlinked and have an impact on each other, and the characteristics of Gen Z effect the coach-athlete relationship. The insights from the coaches’ have been distilled into three practical applications. Firstly, working effectively with Gen Z athletes, secondly, cultivating the coach-athlete relationship and finally some key ideas for developing the coach-athlete relationship.
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    Locomotor demands and injury incidence of match play in a South African Premier Soccer League team.
    (Stellenbosch : Stellenbosch University, 2024-03) De Lange, Menanto; Kraak, Wilbur Julio; De Waal, Simon; Stellenbosch University. Faculty of Medical and Health Sciences. Dept. of Exercise, Sport and Lifestyle Medication.
    ENGLISH ABSTRACT: This study aimed to assess locomotor demands and analyse injuries during match play in a South African Premier Soccer League (PSL) team across three competitive seasons. Data were collected from 38 professional soccer players (age 25.5 ± 4.8 years, height 176.9 ± 6.0 cm, weight 72.5 ± 9.3 kg) of a PSL club. Match locomotor and injury data was collected for six matches played in (2019/2020) as well as 62 matches played over two full soccer seasons (31 in 2020/2021 and 31 in 2021/2022). All match locomotor data was captured by 10-Hz global positioning systems (GPS) hardware with total distance (TD), high-speed running (HSR), sprint distance (SD), total actions (TA), accelerations (ACC), decelerations (DEC), maximal velocity (MV), TD/min, HSR/min, SD/min, and TA/min being analysed. All injuries were recorded and diagnosed following the Orchards Sports Injury and Illness Classification system. Injury incidence was reported per 1000 hours of exposure. Team match load metrics were: TD (10045 ± 813 m), HSR (1563 ± 520 m), SD (308 ± 214 m), TA (77 ± 23), ACC (31 ± 11), DEC (46 ± 14), MV (29.7 ± 2.7 km/h), TD/min (104.9 ± 8.7 m/min), HSR/min (16.3 ± 5.5 m/min), SD/min (3.2 ± 2.2 m/min), and TA/min (0.8 ± 0.2). Locomotor demands differed between playing positions for all GPS variables measured (p=<0.01). For variables SD, TD/min, SD/min, and TA/min there was a change in locomotor demands when comparing 1st and 2nd half (p=<0.01). A total of 24 injuries were recorded with the overall injury incidence of 22/1000 hours of match play with defenders suffering the highest injury rate. The locomotor demands and injury incidence in this SA PSL team is similar to international standards. However higher match locomotor outputs and lower injury incidence were reported than previously in the PSL. Forwards had higher match outputs for all variables than midfielders and defenders, which is differed with previous studies in Europe. This study provides a better understanding of locomotor demands and injury incidence in a South African PSL team which could be used to optimise performance and injury prevention in future.
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    Muscle oxygenation and performance adaptations in trained cyclists following a polarized and threshold training intervention
    (Stellenbosch : Stellenbosch University, 2023-12) Fleming, Colin; Terblanche, Elmarie; Stellenbosch University. Faculty of Medical and Health Sciences. Dept. of Exercise, Sport and Lifestyle Medication.
    ENGLISH ABSTRACT: Training intensity, and its distribution within a training program, is a key variable in positively or negatively influencing athletic performance, through varying physiological adaptations stemming from different training intensities. However, experimental research investigating physiological adaptations to various training intensity distributions is scarce. As such, the purpose of this study was to examine the performance and peripheral adaptations to a polarized (POL) and a threshold (THR) training intervention in trained cyclists. Seventeen trained road and mountain bike cyclists, including men (n = 13) and women (n = 4), aged between 19 and 49 years, participated in this study. This study followed a pre-post design, with a random assignment of participants into two experimental groups: a POL or a THR training group. The pre- and post-tests included a ramp incremental test to exhaustion and a 30-s Wingate test, with concurrent cardiorespiratory, muscle oxygenation, power, heart rate, and blood lactate data collection. The intervention consisted of six weeks of polarized (80/0/20% in zone 1/2/3) or threshold (45/55/0% in zone 1/2/3) training. The findings of the present study indicate that both POL and THR training stimulate improvements in power output over a 6-week training period. There were no significant group*time interactions observed for any measured variable (p > 0.05), however, effect sizes were calculated to investigate the magnitude of differences after the training intervention. Both THR and POL displayed improvements in power output at LT2, and PPO, however the effect size was numerically greater after THR than POL training (ES = 0.54, 0.29). It was also found that the effect size of muscle oxygen utilization was greater after POL than THR at LT1, LT2, PPO, and after the 30-s Wingate (ES = 0.72, 0.91, 0.74, 1.76). The magnitude of change in VO₂max was larger for POL than THR (5.9% vs. 1.1% improvement, respectively; ES = 0.40). The THR group showed a greater numerical increase in effect size, compared to POL in anaerobic capacity and explosive power (ES = 0.34, 0.40). A moderate and a small numerical increase was observed in effect size in exercise economy at LT2 and PPO in THR, but not in POL (p > 0.05, ES = 1.11, 0.45). It is suggested that the observed improvement in power output at LT2 and PPO in the POL group may be attributed to peripheral aerobic adaptations, as indicated by an increase in O₂ utilization and VO₂max. Secondly, it is suggested that glycolytic adaptations may contribute to the improvement in power output at LT2 and PPO in the THR group, as reflected by a decrease in VO₂/W, along with increases in anaerobic capacity and explosive power. Over a 6-week period, neither POL nor THR appeared to be superior for improving endurance performance, but they may induce different adaptations.
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    The effect of the 50:22 law trial on the Currie Cup and Varsity Cup rugby tournaments between 2021 and 2022
    (Stellenbosch : Stellenbosch University, 2023-12) Strydom, Wikus; Kraak, Wilbur; Vaz, Luiz; Tucker, Ross; Stellenbosch University. Faculty of Medical and Health Sciences. Dept. of Exercise, Sport and Lifestyle Medication
    ENGLISH ABSTRACT: Tactical kicking is a fundamental aspect of rugby union “rugby”, playing a strategic role in attack and defence, contributing to the success of a team. The 50:22 law was implemented with the aim of compelling defending teams to drop players into the backfield to cover the kick, thereby reducing the number of players in the defensive line and decreasing the line speed during contact situations, lowering the risk of injuries. To the investigators knowledge, the current study was the first to investigate and compare the 50:22 law change to assess the effect of the law change on tactical kicking during match-play. This thesis followed an article format where one research article (Chapter Four) was compiled. The research article aimed to investigate and compare the effect of the 50:22 law changes on rugby union kicking profiles at provincial and university levels between the 2021 and 2022 tournaments. This study employed a descriptive retrospective research design, utilising video-based performance analysis (Nacsport Scout Plus) for data collection. The initial performance indicators and their operational definitions were established using published peer-reviewed studies, and input from an expert panel further validated and enhanced the relevance and comprehensiveness. For reliability of the coded performance indicators, the primary investigator, and an external coder independently re-coded 25% (44 matches) of the matches. The resulting Cohen's Kappa Coefficients demonstrated very good agreement for both intra-coder (r=0.98) and inter-coder (r=0.97) reliability. For this study, a comprehensive analysis was conducted on all the kicks from 177 matches during the 2021 and 2022 Currie Cup (CC) and Varsity Cup (VC) rugby tournaments, resulting in a total of 6,479 kicks being examined across the two seasons. When considering the specific tournaments, the CC yielded a total of 1,497 kicks in the 2021 season, and 1,628 in 2022. On the other hand, the VC produced 1,881 kicks during 2021, and 1,437 in 2022. In 2022, there were 53 successful 50:22 kicks, 30 in the CC and 23 in the VC. That equals to less than one successful 50:22 kick per match. The results indicate that the implemented 50:22 law influence the kicking profile at provincial and university level rugby in South Africa. When combining both tournaments, the results revealed a significant increase in the number of kicks by scrum halves (p < 0.001) and box kicks (p = 0.03) in 2022 compared to 2021. This aligns with the trend that has been seen in modern rugby in previous studies. There was a significant decrease in the number of kicks by flyhalves (p = 0.01), fullbacks (p = 0.01), and kicks that took place from a received kick (p = 0.01). The decrease in the number of kicks by fullbacks and from received kicks are likely due to teams deploying additional backfield players to counter the 50:22 kick, thereby enhancing counter-attacking opportunities upon receiving kicks. The results of the CC revealed an increase in the percentage of kicks by scrum halves (p = 0.01) and inside centres (p < 0.001). This result, together with the decrease in the number of kicks by fly halves (p < 0.001), suggests that teams at the professional level, distribute the responsibility of kicking more amongst the backline players. The study showed an increase in punt kicks (p = 0.01), likely due to a 50:22 kick needing a longer type of kick. The VC results revealed a significant decrease in the number of kicks, likely due to additional space in the defensive line, encouraging teams to run with the ball. A decrease in the number of kicks in the second quarter (p = 0.02) and an increase in the percentage of kicks in the fourth quarter (p = 0.01) was observed. This could possibly be due to teams using the 50:22 kick as an attacking option. When comparing the 2022 season of the CC and VC, the results revealed that scrum halves kick significantly more (p < 0.001) and flyhalves significantly less (p < 0.001) in the CC compared to VC. The VC used the punt kick significantly more (p < 0.001) compared to the CC, whereas the CC used contestable kicks (p < 0.001) significantly more. The findings deepen our understanding of how the 50:22 law influences how teams’ utilise kicking strategies during the match. This study provides valuable insights to coaches, performance analysts, and players in their preparation and utilisation of this law in their kicking strategy.