Factors that influence the performance of hop tests
General Material Designation
[Thesis]
First Statement of Responsibility
Ghulam, H. S.
.PUBLICATION, DISTRIBUTION, ETC
Name of Publisher, Distributor, etc.
University of Salford
Date of Publication, Distribution, etc.
2016
DISSERTATION (THESIS) NOTE
Dissertation or thesis details and type of degree
Thesis (Ph.D.)
Text preceding or following the note
2016
SUMMARY OR ABSTRACT
Text of Note
Hop tests are useful measures of physical performance and athletic function, and they can also be used to monitor progress, as well as recommend whether a return to sport or normal activity is likely to be beneficial or harmful for those recovering from a sporting injury or surgical intervention. Hop tests can combine and test the different elements that may have been affected due to an injury, for example joint stability, muscle strength and neuromuscular coordination. There is limited literature exploring the factors which influence the performance of hop tests, and provides reference values for each of the individual test during different athletic tasks. A better understanding of these factors would offer a clear vision about what reflect the hop performance in both healthy and anterior cruciate ligament reconstructed (ACLR) participants during common screening tasks. This thesis includes four themed studies. The first study aimed to investigate the reliability of the individual tests which consist of hop tests, two-dimensional (2-D) Frontal-Plane Projection Angle (FPPA), balance tests, force generation tests, and isokinetic strength testing to establish the measurement error of these. The findings of first study revealed that the majority of the intraclass correlation coefficients (ICC) values for all tests were excellent across all variables during within- and between-day sessions testing, showing these tests to be reliable. However, impulses from 0 - 100, 200, 250, 300 ms had less reliable variables across all isometric mid-thigh pull (IMTP) results. The second study established the differences between right and left leg performances across all tests and to describe reference values for the limb symmetry index (LSI) for hop tests and isokinetic muscle strength tests for recreationally healthy participants. However, the main reason behind conducting this study was to identify whether one leg's performance can define the other and to determine the reference values in a heathy population, and further to this investigation, if the limbs were found to be symmetrical across all the tests, then the next study would be carried out using the right leg only. This study has concluded that no differences were found between right and left leg performance during all the tests. In addition, symmetry between limbs existed during both hop and isokinetic muscle strength tests, from which it can be concluded, that one leg's performance can define the other. The third study examined the relationship between all of the tests (2-D FPPA, balance, force generation, and isokinetic muscle strength tests) and hop performance during single-leg hop for distance and crossover hop tasks in healthy participants. This would then also provide the reference values that are needed for each of the individual tests. The conclusion of this element of the study is that force generation and ankle plantar flexion strength seem to be the most contributing factors to hop performance in a healthy population. The final study aimed to examine the differences between injured and non-injured leg performances across all tests and describe reference values for the LSI for hop tests and isokinetic muscle tests in ACLR participants. Also, to investigate the relationship between all of the tests and hop performance during single-leg hop for distance and crossover hop tasks for the injured and non-injured limbs, and provide the reference values that are needed for each of the individual tests for both limbs. This study has found that dynamic force generation and both quadriceps and hamstring muscle strength seem to be the most contributing factors to hop performances for the injured limb, while the uninjured leg failed to show any association to hop performance and does not perform in a manner which could be regarded as normal. This thesis has expanded that hop tests can be used in a clinic to indicate potential deficits in strength or force generation in lower limbs. Moreover, provided reference values in a physically active population and ACLR participants for hop tests and all the related tests. Also, demonstrated the relationship between all of the tests and hop performance tests in a healthy population and in ACLR participants. Lastly, established the drivers of hop performance are different in the ACLR limb and the non-injured limb compared to those in healthy.