Resumen de The Short-Term Effect of Kettlebell Swings on Lumbopelvic Pressure Pain Thresholds: A Randomized Controlled Trial

Brandon M. Keilman, William J. Hanney, Morey J. Kolber, Patrick S. Pabian, Paul A. Salamh, Carey E. Rothschild, Xinliang Liu

• The purpose of this study was to investigate the short-term effect of kettlebell swings (KBSs) on lumbopelvic pressure pain thresholds (PPTs) in healthy adults. Sixty participants (male = 23, female = 37, mean age = 25.12 ± 2.86 years, height = 170.73 ± 9.2 cm, mass = 70.49 ± 13.32 kg) were randomized into one of 2 groups. The experimental group performed a warm-up followed by 8 consecutive 20-second rounds of KBS with 10-second rest periods. The control group performed the warm-up alone. An evaluator blinded to group assignment, assessed PPTs immediately before and after the intervention using a handheld pressure algometer. The algometer was applied to the regions of the right paravertebral (PVM), quadratus lumborum (QL), and piriformis (PF) muscles perpendicular to the skin based on standardized palpation procedures. The participants were instructed to report when sensation changed from “comfortable pressure” to “slightly unpleasant pain.” No significant group differences existed at baseline for PPTs (PVM p = 0.068; QL p = 0.134, & PF p = 0.105). Significant group by time interactions existed for each site after the interventions (PVM, p = 0.018; QL, p = 0.004; PF, p = 0.026) favoring the KBS group. Results suggest that KBSs create a reduction in muscle sensitivity to noxious pressure based on pressure algometry measurements. These findings may be due to the unique cyclic muscle contraction associated with KBSs, which has been proposed to facilitate removal of muscle metabolites. The findings of this study provide a foundation for future studies to examine the use of this type of training in patients with low back pain of a muscular etiology or postexercise muscle soreness. Furthermore, future studies should evaluate specific mechanisms for these effects.