This document discusses a study on how different sports shoe insole structures can decrease ground reaction force on flat feet. The study aims to compare ground reaction force between normal and flat feet, and examine how insole structures can reduce this force for flat-footed runners. Subjects between 18-25 years old with a BMI of 18-23 who run 10-15km per week are tested. Force platforms measure vertical ground reaction force while subjects run at a controlled velocity and distance in shoes with varying insole structures. The relationship between insole structure and force absorption/distribution is analyzed to identify solutions for people with flat feet.

2. A Study of the Sports Shoes' insole Structures that Affect Decreasing Ground Reaction Force on Foot of Flat Foot Pattern Introduction Foot’s structures consist of 3 main components - Forefoot - Midfoot - hindfoot or rearfoot

3. Normal foot Flat foot High arch A Study of the Sports Shoes' insole Structures that Affect Decreasing Ground Reaction Force on Foot of Flat Foot Pattern Introduction

4. overpronation normal supination D-maq, 2547-2548 A Study of the Sports Shoes' insole Structures that Affect Decreasing Ground Reaction Force on Foot of Flat Foot Pattern Introduction Ratio of pronation symptom in boys 27% 0% 73%

5. Ratio of pronation symptom in girls 39% 60% 1% overpronation normal supination D-maq, 2547-2548 A Study of the Sports Shoes' insole Structures that Affect Decreasing Ground Reaction Force on Foot of Flat Foot Pattern Introduction

6. Functions of sports shoes -absorb the ground reaction force on feet -protect the feet from pain during exercising A Study of the Sports Shoes' insole Structures that Affect Decreasing Ground Reaction Force on Foot of Flat Foot Pattern Introduction

7. A Study of the Sports Shoes' insole Structures that Affect Decreasing Ground Reaction Force on Foot of Flat Foot Pattern Introduction

8. Purpose 1.. To compare the ground reaction force between on normal foot and on flat foot . 2. Study the sports shoes’ insole structure which affects decreasing the ground reaction force on foot of flat foot pattern by using Force Platform for evaluating that force A Study of the Sports Shoes' insole Structures that Affect Decreasing Ground Reaction Force on Foot of Flat Foot Pattern

9. Research boundary Study i n Mahidol University students having the Body Mass Index (BMI) during 18 to 23 kilograms /square meters , exercising by running 10-15 kilometer per week for 3 months Age : 18-25 years old A Study of the Sports Shoes' insole Structures that Affect Decreasing Ground Reaction Force on Foot of Flat Foot Pattern

10. 1. To study the relationship of sports shoes’ insole structure in absorbing and spreading the ground reaction force on flat foot 2. Analyze the data and conclude the method to solve the problem for people having feet of flat foot pattern A Study of the Sports Shoes' insole Structures that Affect Decreasing Ground Reaction Force on Foot of Flat Foot Pattern

11. Variable Sports shoes' insole structures Ground reaction force Age Body Mass Index Velocity Strength ness Independent variable Dependent variable Controlled variable A Study of the Sports Shoes' insole Structures that Affect Decreasing Ground Reaction Force on Foot of Flat Foot Pattern

12. Definitions Force The ground reaction force that impact on subjects’ left foot when it contracts Force Platform at the fix point. In this research we will study the vertical ground reaction force only. The velocity that the subjects have to run on Force Platform is equal to 3.5 meter/sec A Study of the Sports Shoes' insole Structures that Affect Decreasing Ground Reaction Force on Foot of Flat Foot Pattern Controlled velocity

13. Definitions The distance that the subjects run on Force Platform is equal to 4.5 meter The pattern of foot segregated by analyzing the foot’s photographs to the lowered arch group and flat arch group A Study of the Sports Shoes' insole Structures that Affect Decreasing Ground Reaction Force on Foot of Flat Foot Pattern Controlled distance Flat foot

14. Related Research Effects of Shoe Inserts and Heel Height on Foot Pressure, Impact Force, and Perceived Comfort During Walking. (Yung-Hui L and Hong WH.,2005) Biomechanical aspects of running. (Nigg BM, 1986) A Study of the Sports Shoes' insole Structures that Affect Decreasing Ground Reaction Force on Foot of Flat Foot Pattern