OBJECTIVES To compare pre-season to post-season changes on a battery of clinical neurological outcome measures between non-contact, contact, and collision sport athletes over multiple seasons of play. METHODS 244 high school and collegiate athletes participating in multiple non-contact, contact, and collision sports completed standardized annual pre-season and post-season assessments over 1-4 years. Pre/post-season changes in 10 outcome measures assessing concussion symptoms, neurocognitive performance, and balance were compared between the groups using linear mixed models. RESULTS Small, but statistically significant overall pre/post-season change differences were present between the groups for Axon computerized neurocognitive test processing speed, attention, and working memory speed scores (Axon-PS, Axon-Att, Axon-WMS), as well as Balance Error Scoring System (BESS) total score. Small seasonal declines not exceeding reliable-change thresholds were observed in the collision sport group relative to the contact and non-contact groups for Axon-PS and Axon-Att scores. The collision and contact sport groups demonstrated less pre-/post-season improvement than the non-contact sport group for Axon-WMA and BESS, with less BESS improvement also observed in the collision sport group relative to the contact sport group. Overall, longitudinal performance on all 10 outcome measures remained stable in all 3 groups over 4 years. CONCLUSION Our findings do not necessarily support the notion that participation in sports associated with exposure to repetitive head impacts has clinically meaningful cumulative effects over the course of a season, nor over four consecutive seasons in high school and collegiate athletes.

中文翻译：

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日常运动参与对短期临床神经系统结果的影响：非接触，接触和碰撞运动运动员的比较。

目的比较多个运动季节非接触，接触和碰撞运动运动员之间一系列临床神经学结果指标的季前变化与季后变化。方法244名参加多种非接触，接触和碰撞运动的高中和大学运动员在1-4年内完成了标准的年度季前和季后评估。使用线性混合模型比较了各组之间的10种评估脑震荡症状，神经认知表现和平衡的结果指标的季前/季后变化。结果Axon计算机化的神经认知测试处理速度，注意力和工作记忆速度评分（Axon-PS，Axon-Att，Axon-WMS）在各组之间存在较小但具有统计学意义的总的季节前/季后变化差异，以及平衡误差评分系统（BESS）的总得分。相对于接触和非接触组的Axon-PS和Axon-Att得分，在碰撞运动组中观察到小的季节性下降不超过可靠变化阈值。与Axon-WMA和BESS的非接触式运动组相比，碰撞和接触式运动组在赛季前/季后的改善较小，与接触式运动组相比，在碰撞运动组中也观察到较少的BESS改善。总体而言，在过去4年中，所有3组的所有10项结果指标的纵向表现均保持稳定。结论我们的发现不一定支持以下观点：参加重复性头部冲击相关的运动在整个季节中具有临床意义的累积效应，