Corticospinal changes induced by fatiguing eccentric versus concentric exercise     

Yoann M. Garnier  Christos Paizis  Romuald Lepers 《European Journal of Sport Science》2019,19(2):166-176

The present study assessed neuromuscular and corticospinal changes during and after a fatiguing submaximal exercise of the knee extensors in different modes of muscle contraction. Twelve subjects performed two knee extensors exercises in a concentric or eccentric mode, at the same torque and with a similar total impulse. Exercises consisted of 10 sets of 10 repetitions at an intensity of 80% of the maximal voluntary isometric contraction torque (MVIC). MVIC, maximal voluntary activation level (VAL) and responses of electrically evoked contractions of the knee extensors were assessed before and after exercise. Motor evoked potential amplitude (MEP) and cortical silent period (CSP) of the vastus medialis (VM) and rectus femoris (RF) muscles were assessed before, during and after exercise. Similar reductions of the MVIC (?13%), VAL (?12%) and a decrease in the peak twitch (?12%) were observed after both exercises. For both VM and RF muscles, MEP amplitude remained unchanged during either concentric or eccentric exercises. No change of the MEP amplitude input–output curves was observed post-exercise. For the RF muscle, CSP increased during the concentric exercise and remained lengthened after this exercise. For the VM muscle, CSP was reduced after the eccentric exercise only. For a similar amount of total impulse, concentric and eccentric knee extensor contractions led to similar exercise-induced neuromuscular response changes. For the two muscles investigated, no modulation of corticospinal excitability was observed during or after either concentric or eccentric exercises. However, intracortical inhibition showed significant modulations during and after exercise.  相似文献   

Finding the missing Einsteins: Expanding the breadth of cognitive and noncognitive measures used in academic services     

《Contemporary educational psychology》2020

Education researchers, policymakers, and practitioners are concerned with identifying and developing talent for students with fewer opportunities, especially students from historically marginalized groups. An emerging body of research suggests “universally screening” or testing all students, then matching those students with appropriate educational challenges, is effective in helping marginalized students. However, most tests have focused on two areas: math and verbal reasoning. We leverage three nationally representative samples of the U.S. population at different time points that include both novel cognitive measures (e.g., spatial, mechanical, and abstract reasoning) and non-cognitive measures (e.g., conscientiousness, creativity or word fluency, leadership skill, and artistic skill) to uncover which measures would improve proportional representation of marginalized groups in talent identification procedures. We find that adding spatial reasoning measures in particular—as well as other non-cognitive measures such as conscientiousness, leadership, and creativity—are worthwhile to consider for universal screening procedures for students to narrow achievement gaps at every level of education, including for gifted students. By showing that these nontraditional measures both improve proportional representation of underrepresented groups and have reasonable predictive validity, we also broaden the definition of what it means to be “gifted” and expand opportunities for students from historically marginalized groups.  相似文献   

Comparison of 10 vs. 20 min neuromuscular training for the prevention of lower extremity injuries in male youth football: A cluster randomised controlled trial     

Anna Lina Rahlf  Astrid Zech 《Journal of sports sciences》2020,38(19):2177-2185

ABSTRACT