Influence of a Functional Core Stability Program on Trunk and Knee Joint Biomechanics in Female Athletes During Lateral Movements.

ABSTRACT: Mornieux, G, Weltin, E, Friedman, C, Pauls, M, Forsythe, S, and Gollhofer, A. Influence of a functional core stability program on trunk and knee joint biomechanics in female athletes during lateral movements. J Strength Cond Res 35(10): 2713-2719, 2021-Trunk positioning has been shown to be associated with knee joint loading during athletic tasks, especially changes of direction. Quasistatic and conventional core stability (CS) training did not improve the biomechanics of cutting maneuvers according to reports in the literature. The purpose of this study was to test whether a 5-week dynamic and functional CS training program would improve trunk positioning and knee joint control during lateral movements. Nineteen female athletes participated in a longitudinal study, where lateral reactive jumps (LRJs) and unanticipated cuttings were performed before and after CS training (15 training sessions within 5 weeks) while 3D kinematics and kinetics were measured. In addition, core endurance and power were evaluated. Core stability training increased trunk rotation in the new movement direction (p = 0.02) during LRJ. However, lateral trunk lean was significantly increased during LRJ (from 5.6 to 7°) and cuttings (from 3.8 to 5.8°) after CS training. Knee joint abduction moment was not influenced. Finally, core endurance (p < 0.01) and core power (p < 0.001) were significantly improved after CS training. A 5-week dynamic and functional CS training program improved core muscle endurance and power. This might explain the better trunk rotation toward the new movement direction during LRJ; however, it was not effective during unanticipated cuttings. The practical application of this research will allow strength and conditioning professionals to setup training programs with simple and relevant exercises to increase the core endurance and power of trained individuals.

Influence of a Full-Body Compression Suit on Trunk Positioning and Knee Joint Mechanics During Lateral Movements.

Trunk positioning has been shown to be associated with knee joint loading during athletic tasks, especially changes of direction. The purpose of the present study was to test whether a full-body compression suit (FBCS) would improve trunk positioning and knee joint control during lateral movements. Twelve female athletes performed lateral reactive jumps (LRJ) and unanticipated cuttings with and without the customized FBCS, while 3D kinematics and kinetics were measured. FBCS did not influence trunk positioning during LRJ and led to increased trunk lateral lean during cuttings (P < .001). However, while wearing FBCS, knee joint abduction and internal rotation angles were reduced during LRJ (P < .001 and P = .013, respectively), whereas knee joint moments were comparable during cuttings. FBCS cannot support the trunk segment during unanticipated dynamic movements. But, increased trunk lateral lean during cutting maneuvers was not high enough to elicit increased knee joint moments. On the contrary, knee joint abduction and internal rotation were reduced during LRJ, speaking for a better knee joint alignment with FBCS. Athletes seeking to improve trunk positioning may not benefit from a FBCS.