Activity of periscapular muscles and its correlation with external oblique during push-up: Does scapular dyskinesis change the electromyographic response?     

Rodrigo Cappatode de Araújo  André Luiz Torres Pirauá  Ana Carolina Rodarti Pitangui 《Journal of sports sciences》2018,36(5):571-577

Scapular dyskinesis is the term used to describe changes in the positioning or movement of the scapula. Such dysfunction is associated with changes in the activation of the scapular muscles. However, the influence of the axial muscles on the scapular muscles activity of subjects with scapular dyskinesis is unknown. This study aimed to compare the electromyography (EMG) activity of periscapular muscles and its correlation with the external oblique muscle during the execution of push-up performed in different surfaces, in volunteers with and without scapular dyskinesis. Thirty-six men, divided in two groups (control and dyskinesis), performed push-up on stable and unstable surface. The EMG activity of serratus anterior (SA_5th and SA_7th fibers), upper (UT) and lower (LT) trapezius, external oblique (EO) was recorded during execution of each task condition. Statistical analyzes were performed using two way ANOVA repeated measures and Pearson correlation. It was observed effect of interaction between factors, being evidenced increased activity of UT, SA_7th and OE for the control group and decreased activity of SA_5th, SA_7th and EO for dyskinesis group during execution of push-up on unstable surface. In both groups positive correlations (r > 0.47) were observed between EMG activity of SA and EO. In the exercises tested, there seems to be an anatomical and functional relationship between the SA and EO muscles. The use of the unstable surface promotes increased neuromuscular demand, but the neuromuscular strategies appear to differ between groups.  相似文献   

Sodium bicarbonate ingestion increases glycolytic contribution and improves performance during simulated taekwondo combat     

João Paulo Lopes-Silva  Jonatas Ferreira Da Silva Santos  Guilherme Giannini Artioli  Irineu Loturco  Chris Abbiss  Emerson Franchini 《European Journal of Sport Science》2018,18(3):431-440

Purpose: To investigate the effect of sodium bicarbonate (NaHCO₃) on performance and estimated energy system contribution during simulated taekwondo combat. Methods: Nine taekwondo athletes completed two experimental sessions separated by at least 48?h. Athletes consumed 300?mg/kg body mass of NaHCO₃ or placebo (CaCO₃) 90?min before the combat simulation (three rounds of 2 min separated by 1 min passive recovery), in a double-blind, randomized, repeated-measures crossover design. All simulated combat was filmed to quantify the time spent fighting in each round. Lactate concentration [La^?] and rating of perceived exertion (RPE) were measured before and after each round, whereas heart rate (HR) and the estimated contribution of the oxidative (W_OXI), ATP (adenosine triphosphate)-phosphocreatine (PCr) (W_PCR), and glycolytic (W_{[ La^? ]}) systems were calculated during the combat simulation. Results: [La^?] increased significantly after NaHCO₃ ingestion, when compared with the placebo condition (+14%, P?=?0.04, d?=?3.70). NaHCO₃ ingestion resulted in greater estimated glycolytic energy contribution in the first round when compared with the placebo condition (+31%, P?=?0.01, d?=?3.48). Total attack time was significantly greater after NaHCO₃ when compared with placebo (+13%, P?=?0.05, d?=?1.15). W_OXI, W_PCR, VO₂, HR and RPE were not different between conditions (P?>?0.05). Conclusion: NaHCO₃ ingestion was able to increase the contribution of glycolytic metabolism and, therefore, improve performance during simulated taekwondo combat.  相似文献   

Using sensemaking as a lens to assess student learning on corporate social responsibility and sustainability     

Lutz Preuss  Isabel Fischer  John M. Luiz 《Higher Education Quarterly》2023,77(4):676-692

Prior literature suggests that teaching corporate social responsibility (CSR) and sustainability has led to little development of students' reflexive engagement with the challenges of sustainable development. To shed light on this criticism, we apply sensemaking—as entailing the three stages of scanning for information, interpreting it and identifying alternatives of action—to CSR/sustainability education. Analysing cognitive maps of CSR, drawn by undergraduate finalists from a UK business school, we find that students are able to produce complex cognitive maps in terms of scanning for information; however, cognitive bottlenecks occur at the second and third stages of sensemaking. A key pedagogical challenge is, therefore, to support students in moving beyond scanning towards developing meaning and acting on that basis. By introducing a sensemaking lens, we add to a deeper understanding of the complexities associated with CSR education as it aids (or impedes) critical engagement and action.  相似文献