Comparison of Adidas and Nahrin shoes in some biomechanical variables related to tibia stress fracture in male recreational runners.

Abstract:

Introduction: Today, running is one of the most common movement activities among athletes and people in society. The purpose of this research was to compare the effect of Adidas and Nahrin shoes on some biomechanical variables related to stress fractures of the tibia in healthy young male recreational runners. Materials and methods: In this semi-experimental study, 15 healthy young men (with an average age of 37±2.27 years, height 180.93±5.39 cm and mass 85.30±8.84 kg), Under the same conditions, they performed running at a controlled speed with separate Nahrin and Adidas shoes. The ground reaction force including the maximum reaction forces in both vertical and anterior-posterior directions, loading speed of vertical and anterior-posterior forces, time to reach the maximum vertical and anterior-posterior forces, and finally the total time of these forces in the support phase of running were measured using a dynamometer plate. The obtained information was analyzed with the correlated t test in SPSS software (P<=0.05, Version 20).

Findings: The results showed that although between two types of shoes, in the variables of maximum vertical and anterior-posterior reaction forces, loading speed of vertical and anterior-posterior forces, the time to reach the maximum vertical and anterior-posterior forces and the total time of these forces in the support phase Running, no significant difference was observed (P>0.05), despite this, the time to reach the maximum vertical ground reaction force in Adidas shoes was 8% longer than in Nahrin shoes (P=0.01).

Final conclusion: There is no difference between the two types of Adidas and Nahrin shoes as standard and local shoes in some of the forces applied to the foot during running. Therefore, Nahrin shoes can be recommended for recreational runners with the same characteristics of attracting force and reducing the risk factors of running injuries at a lower cost.

Key words: Adidas shoes, Nahrin shoes - ground reaction force - recreational runners - loading speed

Chapter one:

Design Research

1-1) Introduction

Running is one of the most common movement activities that has increased in this era with the advancement of science and technology of sports culture due to medical recommendations and the increase and improvement of people's attitude to the quality of life, for example, more than 30 million people in America run for fun and time They have chosen their leisure. In general, running causes pressure on the lower limbs, especially the wrist and leg, which can cause repetitive strain injuries, the most common of which is tibia stress fracture. As it was said during physical activities, especially running, during the contact phase of the foot with the ground, it is always affected by the load [1] and forces from the ground, which can be evaluated by measuring the reaction forces of the ground [2].

Ground reaction, for example, studies have reported a significant increase in tibia stress fracture factors when running barefoot compared to running with shoes.

Therefore, shoes can play an important role in reducing these forces on the lower limb. Considering that most domestic and foreign reputable companies have made various claims that their products are more effective in reducing the above-mentioned forces, and we have investigated some of these claims in this research. style="direction: rtl;">1-2) statement of the problem

Stress fracture[3] is a type of bone injury that manifests itself with pain in different areas of the lower limb, these areas frequently occur in the tibia and the distal part of the fibula, the third and second metatarsal bones, the upper thigh and femoral neck, and the distal part of the thigh. (Bischoff[4] et al. 2010). Studies conducted in the field of running show that 24%-67% of recreational runners suffer from injuries.Studies conducted in the field of running show that 24%-67% of recreational runners suffer from running-related injuries, and stress fractures account for more than 50% of all injuries in runners (Milner [5] et al. 2006, Edward [6] et al. 2010, Bischoff et al. 2010)

Running, when the foot contacts the ground and is placed in the support phase [7], is affected by the ground reaction force [8] (GRF). The ground reaction force is not always constant, so increasing the speed of running and walking increases the maximum vertical force of the ground by about 2 to 5 times the body weight. In the research literature, reducing the amount of ground reaction force is one of the main goals of shoe manufacturers, and shock absorption was always considered as a fundamental problem (Nigg et al., 2010) [9]. Various approaches in measuring the effects of shoes on the ground reaction forces in improving performance have attracted the attention of researchers, which include shoe weight (Logan[10] et al., 2010; Nigg et al. 2010, Wigernig [11] et al. 2009), hardness [12] (Bishop [13] et al. 2006), shoe material and structure (Bishop et al. 2006, Logan et al. 2010, Sharma [14] et al. 2010, Wigernik et al. 2009) and the geometric shape [15] of the shoe (Tanaguchi [16] et al. 2012). Studies have shown that shoes can reduce the likelihood of injury in running by reducing the amount of forces involved (Bishop et al. 2006, Everett[17] et al. 2011, Logan et al. 2010, Meg Guinness et al. 2005, Monderman et al. 2007, Nigg et al. 2006, Nigg et al. 2010, Novacek[18] et al. 1998, Sharma et al. 2010, Vigernik et al. 2009, Zifchuk [19] et al. 2005).

The variety of different shoes in commercial centers, especially foreign shoes, while imposing heavy costs on the applicants, may not be effective in preventing stress fractures. In this regard, among the available shoes In the market that has a reliable brand and is recognized as a standard and successful sports shoe at the international level and has a high popularity among the public, Adidas response cushion 20m is the shoe. Since the said shoe is equipped with adiprene and formotion technologies to absorb the maximum impact when the heel hits the ground, the Adiprene feature achieves this by increasing the cushion effect and formotion by softening the heel impact by creating independent movement for the heel. On the other hand, among the domestic products with an emphasis on national production, is the Nahrin sports shoe, which seems to have the parameters of a standard shoe for running. Therefore, the researcher is trying to compare and analyze two Adidas shoes as a reputable foreign brand and Nahrin shoes as a national product from the point of view of the forces coming from the ground (vertical ground reaction force [20], loading speed [21], posterior ground reaction force [22] and loading speed) which are known to be related to stress fractures in the tibia [23], and To answer the question of whether domestic shoes have the ability to compete with famous and reputable foreign brands in reducing collision forces, as well as in preventing fracture damage caused by pressure? Comparison of the Effect of unstable and control Shoes on the Variables Related to Tibia Stress Fracture during Running in Recreational Runners.

Introduction: Now days, running considered as one of the most common physical activity among athletes and general population. The aim of this study was to compare the effect of Adidas and Nahrein shoes on some biomechanical variables related to tibia stress fracture in healthy male recreational runners.

Materials & Methods: In this semi-experimental study, fifteen healthy men (with age of years, height of cm, and mss of kg) performed running with controlled velocity on the force plate with Adidas and Nahrein shoes.