American Journal of Sports Science 2018; 6(3): 78-82 http://www.sciencepublishinggroup.com/j/ajss doi: 10.11648/j.ajss.20180603.12 ISSN: 2330-8559 (Print); ISSN: 2330-8540 (Online) The Influence of Additional Surface on Force Platform’s Ground Reaction Force Data During Walking and Running Shariman Ismadi Ismail 1, 2, * , Hiroyuki Nunome 2 , Fatin Farhana Marzuki 1 , Izzat Su’aidi 1 1 Faculty of Sports Science and Recreation, Universiti Teknologi MARA, Shah Alam, Malaysia 2 Faculty of Sports and Health Science, Fukuoka University, Fukuoka, Japan Email address: * Corresponding author To cite this article: Shariman Ismadi Ismail, Hiroyuki Nunome, Fatin Farhana Marzuki, Izzat Su’aidi. The Influence of Additional Surface on Force Platform’s Ground Reaction Force Data During Walking and Running. American Journal of Sports Science. Vol. 6, No. 3, 2018, pp. 78-82. doi: 10.11648/j.ajss.20180603.12 Received: April 2, 2018; Accepted: April 20, 2018; Published: May 15, 2018 Abstract: This study compares the vertical ground reaction force exerted from walking and running movement on two different surfaces of a force platform. Five skilled male futsal players were recruited to perform the walking and running tasks over the force platform. In the first setting, the players moved directly in contact with the force platform’s bare surface while in the second setting, the players performed the same tasks on the force platform covered with a typical futsal pitch surface material. The force from the peak heel and peak forefoot strikes were recorded and used for further analysis. A paired t-test was conducted for comparison and the results indicated that there are no significant differences between the two force platform conditions in terms of the magnitude of peak heel strike and peak forefoot strike forces during walking and running. Results also showed that there is a significant difference (p<0.05) on the ratio of the heel and forefoot strike peak force during walking task (1.05 in force platform bare surface, 0.99 in force platform + futsal court surface). While the data obtained in this study suggests that an additional surface on the force plate has no significant effect on the magnitudes of vertical ground reaction force data, there were indeed some changes that occurred on the heel/forefoot strike force ratio in walking task. The result might suggest that an additional surface (futsal court material) on the force platform has some impacts on the movement pattern of the foot during walking task due to the different conditions of the shoe’s outsole-flooring surface interaction. Keywords: Force Plate, Ground Reaction Force, Futsal Court, Movement Pattern 1. Introduction The study of human locomotion has been a subject of interest for such a long time since 300-500 BC to be exact [1]. Historically, the interest upon the knowledge of human locomotion varies by many reasons with different motivations [2] and probably differs based on different scientific community focus research area. During locomotion, force is being applied to the ground, creating a counteracted reaction forces commonly cited as the ground reaction force (GRF). Studies of the ground reaction force on human locomotion has been conducted largely in the past, particularly related to walking and running [3-6]. Past study has shown that humans adjust their leg’s stiffness when running on different surfaces to be able to maintain the running mechanics [7]. This involves alteration on the ground reaction force and the ground contact time to accommodate different surface interactions. In biomechanical study, force platform is commonly used to measure the ground reaction force resulting from the movement of humans or animals [8]. It is widely accepted that the source of the ground reaction force value measured by the force platform is related towards the body’s center of mass. Therefore, there were suggestions that only alterations that are directly or indirectly related to the body’s center of mass would be able to influence changes on the ground reaction force [9]