AUTHOR=Bauer Julian , Hagen Marco , Weisz Nelson , Muehlbauer Thomas TITLE=The Influence of Fatigue on Throwing and YBT-UQ Performance in Male Adolescent Handball Players JOURNAL=Frontiers in Sports and Active Living VOLUME=Volume 2 - 2020 YEAR=2020 URL=https://www.frontiersin.org/journals/sports-and-active-living/articles/10.3389/fspor.2020.00081 DOI=10.3389/fspor.2020.00081 ISSN=2624-9367 ABSTRACT=Purpose: The goal of the present study was to assess the effects of fatigue on throwing and Upper Quarter Y Balance Test (YBT-UQ) performance in this population. Method: All male participants (N=24, age: 14.8 ± 0.7 yrs) were handball players of a regional youth selection team. A radar gun was used for the assessment of throwing velocity. The YBT-UQ was executed assessing medial, inferolateral and superolateral reach directions normalized to the upper limb length together with a composite score. Immediately following a fatigue protocol of different sets of push-ups until failure (i.e., not being able to perform 60% of the initial maximal amount of push-ups), throwing and YBT-UQ performance were assessed again. Results: Fatigue resulted in a significant decrease in throwing velocity (-3%, p = .022, d = .32). Concerning YBT-UQ, the fatigue protocol produced significant decreases for the superolateral reach direction (throwing arm reach: -5%, p = .017, d = .39; non-throwing arm reach: -10%, p < .001, d = .87) and the composite score (throwing arm reach: -2%, p = .026, d = .31; non-throwing arm reach: -4%, p = .001, d = .52) but not for the medial and the inferolateral reach directions. Conclusions: Fatigue was found to be an impairing factor for throwing performance and shoulder mobility and stability. Therefore, a lower level of fatigue and/or a higher tolerance of fatigue is desirable. Strength-endurance and mobility exercises especially for the shoulder girdle may be a valuable addition for the training routine of handball players.