摘要：AIM:To examine the differences in the neuromuscular and kinematic response in middle distancerunnerswhenthestepratewasincreasedto5%and10%respectivelyofthepreferred steprate. MATERIALS AND METHODOLOGY:80 middle distance runners (40 males and 40 females) participated in the study.EMG of 8 muscles (rectus femoris,medial and lateral hamstrings, medialgastrocnemius,tibialisanterior,gluteusmediusandmaximus),kinematicchangesatthe lower limb joints during stance and swing phase of running,foot pressure readings and spatiotemporalgaitpaWrameterswererecordedaseachparticipantranattheirpreferredspeed, 5% increase in preferred speed and 10% increase in their preferred speed while keeping the treadmillspeedconstant. RESULTS:Kinematic analysis showed an increased knee flexion angle at initial contact(p<0.001)anddecreasedkneeflexionangleduringswingphase(p<0.001),Ankleshowedreduced dorsiflexWionangleatinitialcontact(p<0.001)andthehipshowedlesspeakflexion(p<0.001) acrosssteprateconditions. Withanincreasein steprate,a fore footstrikerunningpatternwasseen.Muscleactivitywas signifWicantly increased during the late swing and preWswing at 10% of the preferred speed (p<0.001),with less significant changes during 5% of the preferred speed.During loading response,significant deWcrease in muscle activity (p<0.05) was found between 5% and 10% increaseofpreferredspeed. CONCLUSION:IncreasedcadenceshowedincreasedmuscleactivationandaforefootstrikerunW ning pattern.The kinematic changes documented along with the neuromuscular response across the step rate conditions could be beneficial to runners for rehabilitation and injury prevention.
