Effects of Minimalist Shoes on Pelvic Floor Activity in Nulliparous Women During Running at Different Velocities: a Randomized Cross-over Clinical Trial

Background: women's participation in running has grown dramatically, leading to an increased number of female pelvic floor pathologies (PFM), such as stress urinary incontinence. Objective: to determine the short-term effects of minimalist versus traditional running shoes on PFM EMG activity, femoral range of motion (ROM) and cadence variables in nulliparous women. Methods: prospective, randomized, crossover clinical trial. Fifty-one participants were randomized in two sequences (AB/BA crossover design). Femoral ROM, cadence and PFM activity were recorded. Results: Femur ROM at 6 km/h was higher with minimalist shoes by 1.62 degrees than with traditional shoes (p = 0.001). A main effect of shoe type (p=0.015) consistently observed a higher running cadence with the minimalist shoe compared to the traditional shoe. PFM electromyographic activity reports differences for 11km/h for the total mean (p=0.027) and minimum peaks at 9 km/h (p=0.011) and 11km/h (p=0.048) for the minimalist shoe compared to the traditional ones. Conclusions: Minimalist shoes produce effects on biomechanical running variables. Femur ROM increased to 6 km/h and cadence to 11 km/h with the use of minimalist shoes. The minimalist shoe increased electromyographic activation of PFM in the minimum peaks at speeds of 9 and 11km/h and total mean at speeds of 11km/h.