At present, Simon has a research interest in the laterality and limb dominance in the lower extremities and how this may be detrimental to performance and/or increase in injury risk in runners.

Although possessing a dominant limb is normal, it can be disadvantageous when running, as one limb can be required to increase work to compensate for the weaker side. The repetitive nature of running requires efficient movement patterns to prevent injury by reducing impact acceleration, absorbing the impact forces and promoting correct coordination between muscle activity and the responding joints. Particularly during the stance phases when running, the demand on the lower extremity is high where substantial biomechanical loads are implied on the musculoskeletal tissue structures. Injury can therefore occur if there is an imbalance between either in the biomechanical load applied to the musculoskeletal tissue or the ability of the musculoskeletal tissue to withstand the applied loads, or some combination of the two factors.

The neuromuscular demand to perform the running action as the distance increases during training and/or competition. In this instance, there is an inevitability of progressive fatigue during a run. Exercise induced fatigue during running may evoke non-apparent or worsen pre-existing dominant and non-dominant limb differences which possibly worsen movement patterns due to alterations in proprioception, postural control, or movement co-ordination, impacting upon neuromuscular performance during the running gait, and increase risk of injury. Consequently, this may create unequal force absorption in the musculoskeletal tissue which has less tolerance to loading. Collectively, these factors might influence the execution of the running gait or the parameters of the running gait leading to or worsening laterality, subsequently this may implicate a runner to a heightened injury risk.