Optimal Core Training for Functional Gains and Peak Performance: Cxworx

The American College of Sports Medicine and the United States Department of Health and Human Services recommend that healthy adults, under 65 years of age, complete a strength training routine that includes core exercises twice a week. They specifically advocate core training as a means to improve stability, reduce injury, and maintain mobility. There are countless exercises that target the primary core trunk muscles (abdominal and lumbar) with the aim of providing these benefits. However, it is unknown which exercises elicit the greatest activation thereby maximizing functional gains as well as peak performance. PURPOSE: To determine whether integrated core exercises that require activation of the distal trunk muscles (deltoid and gluteal) elicit greater activation of primary trunk muscles in comparison to isolated core exercises that only require activation of the primary trunk muscles. RATIONALE: We wanted to develop a core program that would optimize functional gains as well as peak performance. METHODS: Twenty participants, 10 men and 10 women, completed 16 randomly assigned exercises (for example, crunch, upper body extension, standing balance, and hover variations). Each exercise was performed for 10 repetitions at a cadence of 15 repetitions per minute with the exception of the hover and balance tasks, which were performed statically for 20 seconds. Therefore, all the exercises were analyzed during a 20 second period of activation. We measured muscle activity with surface electromyography of the anterior deltoid, rectus abdominus, external abdominal oblique, lumbar erector spinae, thoracic erector spinae, and gluteus maximus. In order to determine if the muscle activation differed between exercises, we normalized the active muscle periods, performed a repeated-measures ANOVA and defined the statistical significance at p < 0.05. RESULTS: Activation of the abdominal and lumbar muscles was greatest during the exercises that required activation of deltoid and gluteal muscles. For instance, the hover activity was 20% greater for the rectus abdominus, external abdominal oblique, and lumbar erector spinae compared to a traditional crunch and upper body extension exercise (p = 0.02). CONCLUSION: When completing the core strength guidelines, a routine that incorporates the activation of distal trunk musculature would be optimal in terms of maximizing strength, improving endurance, enhancing stability, reducing injury, and maintaining mobility. CXWORXTM by Les Mills provides this unique combination of core exercises for functional gains as well as peak performance. Introduction The American College of Sports Medicine and the United States Department of Health and Human Services recommend that healthy adults, under 65 years of age, complete a strength training routine that includes core exercises twice a week. In order to meet these guidelines, numerous exercise products, including the Les MillsTM programs, include a core-strengthening component within their conditioning plans. Core exercises are also commonly implemented within both sport and rehabilitation objectives in order to maximize strength, improve endurance, enhance stability, reduce injury, and maintain mobility. Therefore, multiple past studies have focused on how to optimize trunk muscle activation. Despite the extensive previous research, it is unknown if isolation or integration exercises elicit the greatest activation thereby optimizing functional and performance gains. We define integration core exercises as movements that require activation of the proximal limb muscles (deltoid and gluteal) as well as activation of the primary trunk muscles (abdominal and lumbar) in comparison to isolation core exercises that only require activation of the primary trunk muscles. Thus, our purpose was to evaluate the muscle activity of distal and proximal muscles during a series of both isolation and integration exercises. Methods Twenty, healthy college students, 10 men and 10 women, completed the protocol. All the participants gave written informed consent that followed the guidelines of The Pennsylvania State University Human Research Committee. We instrumented each participant with 8 pairs of surface electromyography (EMG) electrodes on the trunk (Figure 1). We are reporting 6 pairs in the current report for simplicity. Prior to electrode placement, we prepared the skin and performed a series of measurements to locate the muscle centers of the anterior deltoid (AD), rectus abdominus (RA), external abdominal oblique (EO), lumbar erector spinae (LE), thoracic erector spinae (TE), and gluteus maximus (GM) according to the recommendations of Cram and Kasman .