The Influence of Soccer Boots Insole’s Surface Roughness and Hardness on Short-Sprint and Change of Direction Performance

The role of footwear is crucial in sports performance.So far, it remains unclear if the aspect of footwear's insoles could substantially influence sports performance.This study examined the effect of soccer boots with different insoles properties (insoles hardness and surface roughness) on soccer-specific change of direction and 6-meter shortsprint performance.A total of ten skilled-soccer players (age: 20.5 1.9 years-old, height: 172.6 4.7cm, weight: 65.8 6.8kg, soccer experience: more than 5 years) maximally completed six-randomised crossover trials of a slalom course and a straight 6m sprint test using the two soccer boots with different insoles (PU and EVA).Timing-gate systems were utilized to record the time of the slalom and sprint test.Differences of resultant performance when running with different insoles were analysed by paired-sample T-test (p<0.05).We found that a relatively higher insoles surface roughness with lower material hardness could potentially contributed to greater change of direction performance.