South African Journal of Sports Medicine最新文献

Background: Body composition and bone health are important for netball from a performance and health perspective (e.g., bone stress injury), given the typical characteristics of players and demands of the game.

Objectives: The objectives of this study are to quantify and compare the positional group-specific body composition and site-specific bone health outcomes of netball players and to establish within-season changes in these variables.

Methods: Forty-seven female netball players (senior: n=23, under-21: n=24) from one Netball Super League (NSL) franchise participated across three seasons (2021-2023). Dual-energy X-ray absorptiometry (DEXA) scans were conducted four times per season. Total body, anteroposterior lumbar spine and total hip scans were performed. General and generalised linear mixed models were used to compare positional groups and age groups, and to investigate within-season changes.

Results: Goal circle netball players had greater total mass and bone mass than midcourt netball players at both levels (p<0.05, effect size: moderate to very large), but not when scaled for height. Senior players had greater lean mass, bone mass, total bone mineral density and bone mineral content than under-21 players (p<0.05, effect size: moderate to very large). No group-level significant changes were observed across a playing season, but individual trends varied.

Conclusion: These findings highlight the importance of continued physical development in the under-21 squad before progressing to a senior squad, as well as the need for individualised approaches to nutritional and training interventions that support physical development, addressing positional requirements and developmental stages. Future research should explore longitudinal body composition trajectories across career phases and multiple teams to refine normative benchmarks.

Background: Knowledge of the electrical characteristics of the athlete's heart is essential for differential diagnosis with latent cardiac pathologies at risk.

Objectives: This study aimed to determine the electrical characteristics induced by refereeing in football.

Methods: This was a cross-sectional study conducted with 57 Burkinabe elite referees divided into two groups: the central referees' group and the assistant referees' group. The recorded ECGs were interpreted according to the 2017 expert consensus criteria.

Results: PR and QT intervals, then the Sokolow Lyon index of the left ventricle, were increased more (p < 0.05) in the central referees' group than in the assistant referees group. Resting heart rate and corrected QT interval were lower (p < 0.05) in central referees. The number of referees with sinus bradycardia (23 vs 18; p = 0.04), early repolarisation (16 vs 9; p = 0.03), incomplete right bundle branch block (14 vs 6; p = 0.02) and left ventricular electrical hypertrophy (17 vs 11; p = 0.03) were higher in the central referees group than in the assistant referees group.

Conclusion: The results indicated that football refereeing was associated with myocardial electrical adaptations, but these adaptations are more frequent in central referees. An evaluation of Doppler echocardiography parameters is recommended to complement these findings.

Background: Although Cricket South Africa has implemented the Long-Term Athlete Development (LTAD) model, there is limited information available about the adoption and implementation of its principles among cricket coaches.

Objectives: This study aimed to gain a better understanding of how South African cricket coaches adopt and implement the LTAD model.

Methods: This study used a quantitative design approach. The sample comprised 86 cricket coaches from nine provinces in South Africa. Coaches responded to questions on a 5-point Likert scale. Data are reported as the mean ± standard deviation.

Results: Overall, coaches reported that the LTAD model helped them to improve their players' performance (4.33±0.90), contributed to their players' development (4.31±0.86), and could be adapted to their coaching needs (4.19±0.87). Also, the LTAD could be effective for the benefit of their players (4.16±0.93) and had agreeable theoretical principles (4.02±0.92). Coaches indicated that the barriers to adopting the LTAD model were the need to educate new coaches and parents (4.33±0.84) and the need to better understand the model's general principles, associated science, and coaching (4.29±0.78). Other barriers included the model's incompatibility with an emphasis on results and competition (3.79±1.08), as well as the players' parents' desire to win at all costs (3.58±1.26).

Conclusion: These results have implications that can be used to provide recommendations which may help Cricket South Africa promote the LTAD model in the South African context.

Background: Self-determined motivation (SDM) and sport psychological coping skills are important for developing footballers.

Objectives: This study examined relationships between chronological age (CA), skeletal age (SA), and psychological variables among South African youth players.

Methods: Data were collected from 109 male players across three football academies (mean CA: 14.8±2.4 years, mean SA: 14.2±2.1 years). Participants completed the Sport Motivation Scale-II (SMS-II) and the Athletic Coping Skills Inventory-28 (ACSI-28).

Results: Amotivation, external, and introjected regulations differed significantly across CA groups, negatively affecting the Relative Autonomy Index (RAI). SDM, as reflected by the RAI, declined with CA, reaching its lowest point between 15 and 17 years. SA grouping revealed significant differences for amotivation and external regulation. Coachability differed across CA and SA groups. Amotivation, external regulation, and coachability showed positive correlations with CA, while amotivation and coachability showed positive correlations with SA. Concentration showed opposite correlations with CA and SA when controlling for the other variable.

Conclusion: CA grouping appeared to reflect differences in SDM more effectively than SA. While some psychological and motivational variables aligned more closely with CA or SA, others did not, highlighting the complex and multifactorial nature of these developmental relationships. Given the low internal consistency of several subscales, these findings should be interpreted cautiously and viewed as exploratory. Future research should adopt longitudinal designs and utilise culturally appropriate, psychometrically robust tools better to understand the development of psychological skills in this population.

Sports dentistry is an emerging area within Sports Medicine that focuses on the prevention, diagnosis and management of oral pathologies in the athletic population. It is not yet a formally recognised subspecialty; however, it is seeking to gain wider acceptance within the context of sports medicine. Oral health is increasingly being linked to overall athlete well-being and performance. The role of the sports dentist encompasses a broad range of oral pathologies that may present in athletes, including oral trauma, periodontal disease, and temporomandibular disorders. Within a high-performance setting, the role of the sports dentist may become integral in the prevention, management and reduction of time-loss due to avoidable dental pathologies. In South Africa, the establishment of the South African Sports Dentistry Association highlights the growing momentum to formalise the field and embed it within the broader high-performance network. Sports dentistry is an evolving field with the potential to enhance player welfare, safety and longevity.

Background: Exercise dependence is a maladaptive pattern of exercise that can lead to physical and psychological impairment. This phenomenon can be assessed using the Exercise Dependence Scale (EDS-R). However, the reliability and validity of the scale have yet to be established for the South African context.

Objectives: The purpose of this study was to verify the factorial structure and reliability of the Exercise Dependence Scale among South African university students.

Methods: A cross-sectional study was conducted among 486 university students (176 males and 303 females, 4 non-binary and 3 participants not willing to disclose their gender) with a range of ages between 18 and 62 (23±6 years) who were invited to complete an online questionnaire comprising a demographic questionnaire and the EDS-R.

Results: Exploratory factor analysis confirmed the seven-factor model of the EDS-R, with all subscales demonstrating acceptable to high internal consistency (α=0.75-0.94). Confirmatory factor analysis indicated good model fit indices (Comparative fit index = 0.96, Tucker-Lewis index = 0.95, Root mean square error of approximation = 0.06, 90% CI: 0.05-0.070, Standardised root mean square error residual = 0.05).

Conclusion: Overall, the results of this study indicate an acceptable fit index, confirming the 7-factor structure of the EDS-R. However, it would be beneficial to remove item 10 from this scale for the South African content or consider rephrasing items 10 and 19. Further research is needed to investigate and verify the factorial structure of the EDS-R in the South African context.

Background: Despite extensive research on batting biomechanics among male cricketers, limited studies focus on female cricket players.

Objectives: This study examines the biomechanical and performance implications of the lateral batting backlift technique (LBBT) and straight batting backlift technique (SBBT) among female cricketers.

Methods: This study aims to bridge this gap by assessing the backlift, its influence on shot execution and its relationship with performance metrics among local (n=18; South African National Women's Cricket Team, also known as the Protea (P) Women's Cricket team (n=9) and non-Protea players (NP) n=9), as well as international (n=34) female players, using high-speed video analysis and StanceBeam bat sensors. Statistical analyses, including Spearman's Rho correlations and Mann-Whitney U tests, were applied to evaluate key performance metrics such as bat speed, impact speed, and wagon wheel shot distribution.

Results: Findings show that local (67%) and international (62%) players used the LBBT, which was associated with greater performance metrics, e.g., strong positive correlations were found between bat speed and impact speed (r=0.85, p<0.001). A significant difference in wagon wheel shot distribution was observed between P and NP players (p=0.039).

Conclusion: Findings suggest that the LBBT offers biomechanical advantages and may be a key contributing factor in optimising female batting performance. Future longitudinal research studies should focus on three-dimensional (3D) motion capture (as well as markerless motion capture) on the LBBT, integrating real-time analytics and expanding sample sizes to include diverse player populations.

Background: Athletes may sustain severe injuries and need to undergo surgery, potentially leading to osteoarthritis (OA). Early diagnosis and rehabilitation can significantly improve outcomes and extend an athlete's career.

Objectives: To determine: 1) prevalence of clinical hip, knee, and ankle OA; 2) association with pain and function; 3) association with severe injuries and surgeries in female professional footballers.

Methods: This cross-sectional study involved female professional footballers who completed online questionnaires on joint pain and function, severe injuries, and surgeries. Their physicians evaluated them for clinical OA (cOA) of the hips, knees, and ankles.

Results: Among 74 participants, cOA prevalence of the hips, knees, and ankles was 2.7% (95% CI: 0-6.4), 5.0% (95% CI: 2.5-10.6), and 8.0% (95% CI: 1.9-14.3), respectively. Pain was present in the hips (p=0.615; Cramer's V=0.132), knees (p=0.556; Cramer's V=0.171), and ankles (p=0.028; Cramer's V=0.391). Joint function was impaired in the hips (p=0.379; Cramer's V=0.214), knees (p=0.738; Cramer's V=0.103), and worse in the ankles (p=0.0778; Cramer's V=0.255). A weak association existed between hip cOA and injuries (p=0.230; Cramer's V=0.193), with moderate associations in the knees (p=0.024; Cramer's V=0.290) and ankles (p=0.168; Cramer's V=0.206). Surgeries were associated with knee cOA (p=0.0578; Cramer's V=0.258) and not ankles (p=1.00; Cramer's V=0.027).

Conclusion: The prevalence of clinical OA was low among female footballers. Pain was the primary symptom, accompanied by impaired joint function. Severe knee injuries and surgeries were linked to cOA. Further research is recommended in this population.

Background: Approximately 23 million sports-related injuries occur annually among African adolescents, with limited epidemiological data on sports-related illnesses across the continent.

Objectives: This study highlights the prevalence, nature, and severity of sports injuries and illnesses in adolescent athletes presenting to a South African sports medicine practice.

Methods: A 12-month prospective longitudinal observational study examined adolescent athletes (aged 10-19) presenting to a South African sports medicine practice. At each visit, athletes and their parents/guardians signed consent forms. Data included demographics, sports type, performance level, injuries and illness details and severity according to the 2020 International Olympic Committee (IOC) consensus statement. The primary outcomes included the number (n) and prevalence (%) of injuries and illnesses for each category.

Results: A total of 373 consultations were recorded (202 injuries; 171 illnesses), 61% included male athletes. Team sports athletes accounted for the majority of injuries (64%), while individual sports athletes experienced a higher proportion of illnesses (65%). Lower limb injuries were most common (61%), with joint and muscle sprains (22%) comprising the predominant pathology type. A significant association was found between sex, age, type of sport, and mode of injury onset (p≤0.05). The respiratory system accounted for 54% of all reported illnesses, with infection being the leading cause (97%). For illnesses, significant associations were observed between the type of sport and the affected organ system and aetiology, as well as between sex and aetiology and mode of onset (p≤0.05). Most injuries and illnesses resulted in 1-7 days of time loss.

Conclusion: Male athletes experienced a higher incidence of medical encounters. Injuries were more prevalent in team sports participants, while illnesses were more common in individual athletes. Lower limb injuries, particularly joint and muscle sprains and respiratory infections, cause short-term time loss. This highlights the need for sport-specific injury and illness prevention in adolescent athletes.