The aim of this study was to generate useful isokinetic normative data for various cervical musculature strength, range of motion and ratio variables based on different positional categories in a sample of senior elite South African rugby players. Normative data was generated for the following variables: peak torque, power generated at 0.2 of a second, active and passive range of motion, the ratio of peak torque flexion to peak torque extension (PTF/PTE), the ratio of peak torque lateral flexion left to peak torque lateral flexion right (PTL/PTR), the ratios of peak torque to body weight (PT/BW) and the ratios of peak torque to lean body mass (PT/LBM). Furthermore, the data gathered from the senior elite players was compared to similar data obtained from a sample of schoolboy rugby forwards to detect statistically significant differences (p < .05). A normative survey design was used in which 189 subjects from eight provincial unions participated in a one off evaluation session. The evaluation session comprised of various anthropometrical measurements and an isokinetic cervical musculature assessment. The normative data, displayed in Stanine tables, was generated for four positional categories: the front row (# 1-3), the second row (# 4-5), the back row (# 6-8) and the backline (# 9 -15). The second row positional category performed the best on the peak flexion torque variable (44.04 Nm). The front row positional category achieved the largest average peak extension torque (65.6 Nm). The second row positional category achieved the largest average peak lateral flexion right torque (69.42 Nm). A similar result was observed with the measurement of peak lateral flexion left torque, with the second row positional category achieving the largest average peak lateral flexion left torque (66.31 Nm). The backline positional category achieved the lowest averages on all the abovementioned peak torque variables. The front row positional category performed the best on the flexion power generated at 0.2 of a second variable (160.92 W). The front row positional category again achieved the largest extension power generated at 0.2 of a second average (237.02 W). The second row positional category achieved the largest lateral flexion right power generated at 0.2 of a second average (269.81 W). Similar results were observed with the measurement of lateral flexion left power generated at 0.2 of a second. The second row positional category achieved the largest lateral flexion left power generated at 0.2 of a second average (259.62 W). Again the backline players achieved the smallest power generated at 0.2 of a second averages for all the above-mentioned power variables. The measurement of passive (PROMFE) and active (AROMFE) range of motion for flexion to extension revealed that the second row had the largest average PROMFE (125.44°). The measurement of AROMFE revealed a similar result. The second row again had the largest average AROMFE (108.45°). The measurement of passive (PROMLF) and active (PROMFE) range of motion for lateral flexion left to right revealed smaller and different results to those found for PROMFE and AROMFE. For the variable of PROMLF the backline players had the largest average PROMLF (119.44°). Conversely, the second row had the largest average AROMLF (106.96°). The calculation of the various ratios revealed great variation between the positional categories. This can be attributed to the functional requirements the players have to adhere to, to be successful in their position. Various other statistical calculations were performed to draw the average force distance graphs for the positional categories for the peak torque variables. Furthermore the force distance graphs were assessed to determine the players’ ability to maintain 80% of peak torque. All the senior elite positional categories proved to be significantly (p < .05) older and heavier than the schoolboy forwards. The senior elite forward positional categories were also significantly (p < .05) taller than the schoolboy forward. There however proved to be no significant difference (p > .05) in stature between the backline and schoolboy forwards. All the positional categories proved to have significantly thicker (p < .05) necks, but significantly shorter (p < .05) cervical spines than the schoolboy forwards. The forward positional categories demonstrated to be significantly stronger (p < .05), on all peak torque measures, than the schoolboy forwards. The same was observed between the backline and schoolboy forwards, however no statistically significant difference (p > .05) was observed between the respective sample groups for the measure of peak lateral flexion left torque. For all the measures of power generated at 0.2 of a second, the senior forward positional categories proved to be significantly more powerful (p < .05) than the schoolboy forwards. The senior backline, although significantly more powerful (p < .05) in the flexion movement pattern, proved to be significantly less powerful (p < .05) than the schoolboy forwards in the lateral flexion right movement pattern. No statistically significant differences (p < .05) were found to exist between the senior backline and schoolboy forwards for the extension and lateral flexion left power generated at 0.2 of a second variables. All positional categories proved to have significantly smaller (p < .05) active and passive ranges of motion compared to the schoolboy forwards. Conversely, the senior elite players had significantly larger (p < .05) ratios (PTF/PTE, PTL/PTR, PT/BW and PT/LBM) than the schoolboy forwards. Literature has identified schoolboy rugby as having a much higher incidence of cervical spinal injuries than senior rugby. It can thus be inferred from the above information that the variables of peak torque and power generated at 0.2 of a second play a important role in safeguarding a player from injury on the field of play. Furthermore, calculated ratios show that senior players, especially the forwards, have undergone adaptive changes in cervical musculature strength to meet the requirements of the position they play in, thereby safeguarding themselves from cervical spinal injury. Proper cervical musculature conditioning has been cited in the literature as being an effective but neglected method of preventing cervical spinal injuries. The generation of normative data, concerning cervical musculature performance, can thus be used to prevent the occurrence of cervical injuries and re-injury of the cervical spine by providing a standard of musculature strength for safe participation in rugby, and possibly other collision type sports, and a quantified guide for successful patient rehabilitation respectively.
| Identifer | oai:union.ndltd.org:netd.ac.za/oai:union.ndltd.org:nmmu/vital:11026 |
| Date | January 2003 |
| Creators | Olivier, Pierre Emile |
| Publisher | University of Port Elizabeth, Faculty of Health Sciences |
| Source Sets | South African National ETD Portal |
| Language | English |
| Detected Language | English |
| Type | Thesis, Masters, MA |
| Format | xxx, 255 leaves, pdf |
| Rights | Nelson Mandela Metropolitan University |
Page generated in 0.0033 seconds