Abstract
M.Tech. (Chiropractic)
Objective: To determine the effect of chiropractic adjustive therapy to the lumbar spine and sacroiliac joints on performance indicators such as sprint times and vertical jump height in asymptomatic, moderate-to-highly-active rugby players. Any dysfunction in the spine can affect biomechanics; neurological functioning of the lumbar spine and sacroiliac joints, as well as the surrounding muscles, and can therefore decrease performance.
Methods: The study involved 60 asymptomatic male participants who were moderate-to-highly-active individuals as determined by the International Physical Activity Questionnaire (IPAQ). The 60 participants were divided equally into two groups: the experimental group (n=30) received chiropractic adjustments to the lumbar spine and sacroiliac joints, and the control group (n=30) rested for five minutes. The study design was based on the once-off model. The objective data used in the study was obtained by the vertical jump height test and the 30-metre sprint speed test. These tests were used to test the participants‟ explosive power and speed, and were obtained before and after the intervention. The immediate effect was obtained by comparing the measurements of the performance indicators before and after the intervention.
Results: The objective results showed that there were improvements in vertical jump height for both the forwards and the backs (rugby players) in the experimental group. Following the chiropractic adjustment, the forwards increased their vertical jump heights by 0.007m (0.5050m-0.4980m) and the backs by 0.017m (0.5245m-0.5075m). In the control group, the forwards jumped 0.01m (0.5071m-0.4971m) lower than before the five-minute rest, and the backs jumped 0.0053m higher (0.5396m-0.5343m). In the sprint speed test, both the forwards and the backs in both the experimental and the control groups performed better when they completed the indicators after the interventions. The forwards in the experimental group ran 0.146s (4.8050s-4.6590s) faster, while the backs ran 0.1055s (4.6040s-4.4985s) faster. In the control group, the forwards ran 0.1358s (5.0329s-4.8971s) faster, while the backs ran 0.0474s (4.6961s-4.6487s) faster.
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Conclusion: In the experimental group, the results demonstrated performance improvements in both the vertical jump height test and the sprint speed test for the forwards as well as the backs.
In the control group, the backs performed better in the vertical jump height and the sprint speed test, while the forwards in the control group performed better in the vertical jump height test and worse in the sprint speed test.
The improvements in the experimental group occurred for both the forwards and the backs, and were greater than for the control group. It can therefore be suggested that the improvements noted were as a result of the chiropractic adjustments having provided a biomechanical advantage.