GROUND REACTION FORCE OF STEP MARCHING: A PILOT STUDY

Abstract

Step marching is the rhythmic movement of the lower extremities which combines hip, knee, and ankle joint movements. The rhythmic movement requires standing on one leg involving the voluntary action of moving the center of mass over the upcoming stance leg. Step marching has been used for body balance training methods among the elderly because it is relatively simple and safe amid practice. The amount and direction of ground reaction force during step marching affecting standing balance has not been thoroughly explored. The objective of this study then, was to compare the effect of two different types of marching (comfortable marching and marching incorporating 90-degree hip and knee flexion) walking on vertical ground reaction force (VGRF). Ten healthy subjects (5 males and 5 females) aged 27.6±3.9 years (mean ± SD) participated. Each subject underwent testing with step marching under the two conditions for 2 minutes, and 10 rounds of preferred-speed walking on 2 force platforms. VGRF was measured with Smart analyzer®, BTS Bioengineering software. Paired t-test revealed significant differences in VGRF among the two conditions of step marching and walking whereby step marching incorporating 90-degree hip and knee flexion showed the highest mean value (11.23±0.5 N/kg), whereas the walking condition showed the lowest (10.09±0.6 N/kg). Two types of step marching provide slightly higher VGRF than walking. Hence, they could be applied as a challenge amid balance training among the elderly in case of weight bearing on the bones and joints is required for progressive strength training of the lower limbs.