The Relationship between the Change in Pelvic Alignment during Moderate-Intensity Running and the Subjective Rating of Perceived Exertion, Rating of Perceived Exertion for Legs and Gluteus Muscles Fatigue in Female Novice and Recreational Runners

Running has become 1 of the 2 most well-known exercises for health; however, running may cause injuries. The purpose of this analytical descriptive study was to examine the occurrence of pelvic drop during moderate-intensity running in female novice and recreational runners; as well as investigating the relationship between the change in pelvic alignment and Rating of Perceived Exertion (RPE), Rating of Perceived Exertion for Legs (RPElegs) and Gluteus muscles fatigue in novice and recreational runners. The participants, aged between 18 and 35 years old, comprised 27 novice runners (less than 1 year of running experience) and 27 recreational runners (2 - 4 years running experience). The participants in both groups performed the maximal oxygen uptake (VO2max) test and ran at a self-selected speed on a treadmill for 30 min at moderate-intensity within the specified heart rate range of 40 - 59 % heart rate reserve (HRR). RPE, RPElegs and sEMG were collected every 2 min and the pelvic kinematic data were also recorded every minute during the 30 min treadmill running test. The data were analyzed with a statistical significance level at p-value < 0.05. The results demonstrated that the time in starting pelvic drop was 8.15 ± 5.07 and 18.37 ± 6.70 min in female novice and recreational runner groups, respectively (p < 0.01). Pearson’s correlations showed relationship between the pelvic alignment and RPE in novice runners (r = 0.47, p < 0.01) and recreational runners (r = 0.39, p < 0.01). Besides, Pearson’s correlations showed relationship between the pelvic alignment and RPElegs in novice runners (r = 0.48, p < 0.01) and recreational runners (r = 0.32, p < 0.01). In both groups, there was no relationship between the pelvic alignment and Gluteus medius and Gluteus maximus muscle fatigue. According to the study, the occurrence of a pelvic drop in novice runners was faster than recreational runners. The study indicated that consideration of RPE and RPElegs variables might be beneficial for female runners and future studies. HIGHLIGHTS The occurrence of pelvic drop in novice runners was faster than recreational runners. There was a relationship between the change in pelvic alignment and RPE and also RPElegs in female novice and recreational runners. The study indicated that consideration of RPE and RPElegs variables might be beneficial for female runners and future studies. GRAPHICAL ABSTRACT