A case study to identify potential innate biomechanical parameters in African distance runners : comparison with Asian runners at different performance levels

![CDATA[Rational & Objective: Runners from Kenya and Ethiopia have shown extraordinary performance in distance running. Some biomechanical parameters, such as stride length and contact time, were shown associated with running performance. However, it remains unclear whether these parameters are an innate attribute of African runners, or can be attained through training. This case study sought to identify some potential biomechanical parameters that might contribute to the performance of African runners. Methods: Four male runners from two regions (Africa and Asia) at two performance levels (elite and recreational) were recruited. They ran on an instrumented treadmill at four running speeds (8 km∙h-1 , 10 km∙h-1 , 12 km∙h-1 , and 15 km∙h-1 ). During running, kinematics and kinetics data were collected to calculate stride length, cadence, contact time, footstrike pattern, energy loss, together with peak braking and propulsion force. Descriptive analysis was used to compare the mean and standard deviation between runners. Region and training effect sizes were expressed as Cohen’s d. Results: The African runners presented with shorter contact time than the Asian runners (Cohen’s d>3.49). African runners tended to demonstrate forefoot, or midfoot landing pattern while Asian runners tended to land with rearfoot (Cohen’s d>2.74). African runners showed less energy loss than Asian runners (Cohen’s d>3.09). We did not find performance specific parameter. Conclusions: Some biomechanical parameters, such as contact time and footstrike pattern, may be innate attributes in African runners, which may potentially lower the energy loss during running. The current sample does not identify any performance specific biomechanical marker.]]