Neuromuscular control and hop performance in youth and adult male and female football players

Objectives: To compare neuromuscular control and hop performance between youth and adult male and female football players. Design: Cross-sectional study. Participants: 119 youth players (13-16 years; 68 males) and 88 adult players (17-26 years; 44 males). Main outcome measures: Neuromuscular control assessed with drop vertical jump (DVJ) and tuck jump assessment (TJA). Hop performance assessed with single-leg hop for distance and side hop. Results: Adult females had smaller normalized knee separation distances (NKSD) during DVJ at initial contact (77.9 +/- 18.5 vs. 86.1 +/- 11.0, p = 0.010) and at maximum knee flexion (59.7 +/- 23.4 vs.74.1 +/- 18.1, p = 0.001) compared to youth females. TJA revealed more technique errors in youths compared to adults (males 10 (8-11) vs. 8 (7-10); females 11 (9-12) vs. 9 (8-11), p < 0.05). Youths demonstrated inferior hop performance (males single-leg hop 142 +/- 18 vs. 163 +/- 17, side hop 41 +/- 12 vs. 52 +/- 12, p < 0.001; females side hop 32 +/- 10 vs. 38 +/- 14, p < 0.05). Conclusions: Youth players demonstrated reduced neuromuscular control during TJA and inferior hop performance compared to adult players. Adult female players demonstrated greater knee valgus during DVJ compared to youth female players. Funding Agencies|Swedish Research Council [2015-02414, 2018-03135]; Medical Research Council of Southeast Sweden [FORSS-936990]; Swedish Research Council for Sport Science (CIF) [P2015-0150, FO2016-0021, FO2018-0012, P2018-0167]; Region OEurostergoEurotland [LIO-527921, LIO-722051]; Futurum-the Academy for Healthcare, Region JoEuronkoEuroping County, Sweden [FUTURUM-766791, FUTURUM-767001]Licensing: This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/).