Relação entre o tipo da pisada e cadência da passada com a frequência de lesão tibial em corredores de rua

Abstract

In search of new healthy lifestyle, many people choose running as exercise. The constant practice of running has caused increasing reports of musculoskeletal injuries among practitioners. Tibial fracture is one of the most frequent injuries in this population. The etiology is multifactorial, where biomechanical factors such as the stride type and the step frequency may be relevant to the development of the lesions. Thus, the objective of the research was to identify the relationship between the stride type and the step frequency of the runners with and without tibial fracture history. Eighteen amateur runners were invited to participate in the research, 9 with a history of injury (Injury Group – IG) and 9 without (Non-Injury Group – NIG), with an average age of 25 ± 5.3 years, and runners for at least 1 year and a training load. ± 4 hours per week. The type of steps used during running (rearfoot, midfoot or forefoot support) was quantified using 2D kinematic data observed in the sagittal plane. Stride cadence was quantified using the accelerometer on the GPS Garmin Forerunner® 935. Nonparametric statistics, the Mann-Whitney test, were used to identify differences between groups. The midfoot step was identified in 5 runners in the injured group (IG) and 5 runners in the non-injured group (NIG). The rearfoot was observed in 4 participants of IG and 4 runners of NIG. The step frequency per minute of IG inviters (n=9; 176 ± 5.2 strides per minute) and NIG (n=9; 180 ± 5.9 strides per minute) where no significant differences were identified (p> 0.05). The midfoot runners in IG (n=5) and NIG showed step frequency per minute similar. (IG=175 ± 7.1 stride per minute and NIG = 181 ± 6.2 stride per minute) (p>0.05). Runners who reported injury and had the rearfoot had a significantly lower frequency of steps (IG=169 ± 6.9 steps per minute; p<0.05) when compared to runners without injury (n=8; 180 ± 5.1 stride per minute). There were no significant differences for a stepped type relationship with frequency of stress tibial injury and for injury-related step frequencies. However positive differences were shown between the type of foot kick and a lower number in the past frequency in the IG.