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- Volume 27, Issue 2, 2015
South African Journal of Sports Medicine - Volume 27, Issue 2, 2015
Volumes & issues
Volume 27, Issue 2, 2015
Author Mike LambertSource: South African Journal of Sports Medicine 27 (2015) http://dx.doi.org/10.7196/SAJSM.634More Less
One thing almost all parents have in common is the desire to ensure the well-being of their children. This translates into protecting them from adversity while at the same time trying to give them skills that make them successful adults. Most parents would like to see their children grow up to be financially independent, happy and contributing to society. Among these are also parents who would like to see their children grow up to become sporting superstars. What is the best style of parenting to achieve these goals?
Cardiovascular and autonomic response induced by a 20-week military training programme in young healthy South African males : original researchSource: South African Journal of Sports Medicine 27, pp 28 –32 (2015) http://dx.doi.org/10.7196/SAJSM.564More Less
Background. Studies investigating the relationship between exercise and haemodynamic regulation conducted in older caucasian and black African populations suggest that lifestyle modification is effective in the management of numerous disease processes. There are few long-term studies in young healthy populations and even less is known about the influence of habitual exercise on autonomic and haemodynamic variables in young black African subjects.
Objective. To investigate the benefit of prolonged exercise on cardiovascular and haemodynamic variables in young healthy black African males.
Methods. Fifty-five healthy male volunteers between 18 and 22 years of age participated in this prospective 20-week medium- to high intensity exercise intervention study with a self-control design. The Finometer Pro (Finapres Medical Systems, the Netherlands) was used for non-invasive data sampling of a number of cardiovascular and autonomic variables. Results were generated by computer algorithm and were analysed using non-parametric Wilcoxon signed rank tests.
Results. Significant (p<0.05) cardiovascular changes included an increase in aerobic capacity, stroke volume, cardiac output and ejection fraction, and a decrease in diastolic blood pressure and heart rate. There was a significant decrease in total peripheral resistance and ascending aorta impedance. Systolic blood pressure, mean arterial pressure and arterial compliance remained unchanged, while the decrease in blood pressure variability was not statistically significant (p>0.05).
Conclusion. The measured changes suggest a favourable response to exercise and imply that habitual exercise may be an important lifestyle modification for reducing the risk of cardiovascular disease in young black African males.
Movement and impact characteristics of South African professional rugby union players : original researchSource: South African Journal of Sports Medicine 27, pp 33 –39 (2015) http://dx.doi.org/10.7196/SAJSM.566More Less
Background. Global positioning system (GPS) technology can provide accurate, non-invasive, real-time movement analysis of players participating in team sports. The application of this technology to rugby union will improve training practices by allowing improved understanding of movement characteristics and more individualised programmes.
Objectives. To characterise the movement and impact patterns of South African professional rugby union players during match play and compare these to previously reported data.
Methods. Nineteen professional rugby players were tracked using GPS systems during 24 matches during the 2013 rugby season. Players were grouped as (i) backs or forwards and (ii) tight forwards, loose forwards, scrumhalves, inside backs or outside backs. Movements were categorised in speed zones corresponding to walking (0 - 2 m.s-¹), jogging (2 - 4 m.s-¹), striding (4 - 6 m.s-¹) and sprinting (>6 m.s-¹). Walking and jogging were classified as low-intensity and striding and sprinting as high-intensity movement zones. An inbuilt triaxial accelerometer (sampling frequency 100 Hz) measured the total impacts >5G and high-intensity impacts >8G. All data were normalised to time on field and reported as mean (standard deviation).
Results. There was no difference between forwards and backs in relative distance covered. Backs reached higher maximum speeds than forwards (backs 8.8 (1.1) v. forwards 7.6 (1.3) m.s-¹, effect size (ES) 1.0, and outside backs were the fastest positional group (9.4 (0.9) m.s-¹, ES 0.4 - 2.2). Players in all positions spent the majority of time walking (79 - 84%). Backs covered more distance than forwards in high-intensity speed zones (forwards 11 (5) v. backs 14 (4) m.min-¹, ES 0.7). Tight forwards covered the most distance in low-intensity zones (63 (6) m.min-1, ES 0.3 - 1.7) while scrumhalves ran the most distance in high-intensity zones (20 (5) m.min-¹, ES 1.2 - 3.6). High-intensity : low-intensity running ratios ranged from 1:13 (tight forwards) to 1:3 (scrumhalves). Loose forwards and inside backs exhibited similar movement patterns. There was no difference in impact variables between forwards and backs. Inside backs sustained the least total impacts (6.5 (1.2) >5G.min-¹, ES 0.9 - 2.0) and high-intensity impacts (0.7 (0.2) >8G.min-¹, ES 0.5 - 1.4).
Conclusions. There were notable differences in the movement of professional rugby union players in different positions, and effective training programmes should reflect these variations.
The cricket bowling performance of different racial groups at a junior provincial level in South Africa : original researchSource: South African Journal of Sports Medicine 27, pp 40 –45 (2015) http://dx.doi.org/10.7196.570More Less
Objective. To investigate the difference in performance and bowling opportunity of black African (BA), coloured/Indian (C/I) and white (W) cricket bowlers at a junior provincial level in South Africa between 2006 and 2012.
Methods. Data of all players performing in the South African inter provincial under-13 (U13), under-15 (U15) and under-19 (U19) tournaments were analysed. Bowling performance (bowling average and the top 20 wicket takers relative to their par representation) and bowling opportunity (number of overs bowled) were compared between racial groups.
Results. There were no significant differences in the bowling averages between BA bowlers and the other racial groups between 2008 and 2012. BA bowling averages were only significantly worse than W bowlers in the U13s in 2006 and U19s in 2007. BA bowling averages were also only significantly worse than C/I in the U13s and U15s in 2007. BA bowlers were below par representation in the top 20 wicket takers in each year for the U15s and U19s and below par representation for the U13s in 2007 - 2009 and 2011. The performance of C/I and W bowlers was relatively similar across the age groups. BA players bowled significantly fewer overs than W bowlers in the U13s in 2006, in the U15s in 2007 and 2009 and in the U19s in 2006, 2007, 2010 and 2011. C/I bowlers bowled significantly fewer overs than W bowlers in the U13s in 2008 and 2009.
Conclusion. The bowling averages of the different racial groups are similar. However, there were relatively few BA bowlers in the top 20 wicket takers each year. This could be because of a lack of highly skilled BA bowlers or the lack of opportunity provided to BA bowlers to bowl in these tournaments.
Source: South African Journal of Sports Medicine 27, pp 46 –49 (2015) http://dx.doi.org/10.7196/SAJSM.596More Less
Background. Injuries occurring at the popular schoolboy rugby festivals in South Africa have not previously been evaluated. A rugby festival is a unique event with multiple matches occurring over a 5-day period and a potentially increased risk of injury compared with adult games.
Objectives. To analyse the prevalence and type of injuries over 2 years of a Johannesburg High School rugby festival, to compare the injuries between the 2 years and to compare the injuries between the 3 days of the festivals.
Methods. The study design was a retrospective, descriptive and observational study. The study population were participating rugby players at the two rugby festivals in 2010 and 2011 who came to the medical tent provided. A standardised medical form was used to capture data.
Results. A total of 626 players participated with 100 injury data sets analysed over the 2 years. The injury rate per player was 17% in year 1and 15% in year 2. There was no statistical difference (p=0.65) in the injury numbers between the 2 years. The injury profiles between the respective days and between the 2 years were not statistically different. Most injuries were to the head/face (30%), with the majority being concussion related (6%). Tackles were the most common mechanism of injury. Overall 24% of injuries were deemed severe enough to stop the players from continuing play. Few injuries required referral for investigations or specialist physician care (19% and 2%, respectively) and most were managed with simple first aid at the primary care level.
Conclusion. The number, nature and mechanisms of rugby injuries at this rugby festival were similar to numerous local and international studies of schoolboy rugby players. Adequate standardised record keeping is recommended to increase knowledge and monitor trends.
Concussion knowledge and return-to-play attitudes among subelite rugby union players : original researchAuthor S.P. WalkerSource: South African Journal of Sports Medicine 27, pp 50 –54 (2015) http://dx.doi.org/10.7196/SAJSM.536More Less
Background. Concussion is a significant health issue in rugby union. However, little is known about players' levels of concussion knowledge or return-to-play (RTP) attitudes.
Objectives. To determine the concussion knowledge and concussion-related RTP attitudes of subelite rugby union players in South Africa.
Methods. Subelite rugby union players (n=127; mean age 24.1 years) completed a measure of concussion knowledge and a concussion related RTP attitude scale. Frequencies were calculated with regard to concussion knowledge and RTP attitudes for the total sample, as well as separately for previously concussed and non-concussed participants. Pearson's χ² tests and t-tests for independent groups were employed to determine significant differences in concussion knowledge and RTP attitudes between previously concussed and non-concussed participants.
Results. Participants displayed varying, yet generally less than optimal levels of concussion knowledge. Knowledge of concussion-related RTP protocols (20 - 23%) and the efficacy of safety equipment (20 - 25%) was particularly poor. The subelite rugby players included in the sample did not hold notably conservative RTP attitudes, with the majority expressing a willingness to participate in practice (74%) and competition (47 - 56%) without having fully recovered from a concussion. No significant differences were apparent with regard to the RTP attitudes and concussion knowledge of the previously concussed and non-concussed players.
Conclusion. The general level of concussion knowledge among subelite rugby union players appears less than optimal. Moreover, the majority of these players expressed an intention to RTP before they had fully recovered from concussion.
Source: South African Journal of Sports Medicine 27, pp 55 –57 (2015) http://dx.doi.org/10.7196/SAJSM.612More Less
Traumatic iliopsoas haematoma is a serious complication of haemorrhage disorders rarely seen in young healthy athletes. It is mostly described in patients on anticoagulant therapy and commonly associated with various degrees of femoral nerve palsy. A 22-year-old male rugby player presented with severe onset of pain in the lower back, right hip flexor/pelvic area following a tackle during a rugby match. Magnetic resonance imaging identified a distinct, hyperechoic heterogeneous mass within the right iliopsoas muscle, confirming a diagnosis of iliopsoas haematoma.The case resolved completely after conservative medical treatment in addition to a period of rest and intense active physical therapy. This case study reports the rare diagnosis of an uncomplicated iliopsoas haematoma following a sports injury in a young athlete.
Source: South African Journal of Sports Medicine 27, pp 58 –59 (2015) http://dx.doi.org/10.7196/SAJSM.613More Less
The clinical presentation of a missed posterior shoulder dislocation has similarities with an idiopathic frozen shoulder masking proper diagnosis at the time of injury. We report a case of a 48-year-old woman with shoulder pain which demonstrates the importance of correct initial diagnosis and management.