Murtagh, CF, Brownlee, TE, O'Boyle, A, Morgans, R, Drust, B, and Erskine, RM. Importance of speed and power in elite youth soccer depends on maturation status. J Strength Cond Res 32(2): 297-303, 2018-Maturation status is a confounding factor when identifying talent in elite youth soccer players (ESP). By comparing performance of ESP and control participants (CON) matched for maturation status, the aims of our study were to establish the importance of acceleration, sprint, horizontal-forward jump, and vertical jump capabilities for determining elite soccer playing status at different stages of maturation. Elite youth soccer players (n = 213; age, 14.0 ± 3.5 years) and CON (n = 113; age, 15.0 ± 4.4 years) were grouped using years from/to predicted peak height velocity (PHV) to determine maturation status (ESP: pre-PHV, n = 100; mid-PHV, n = 25; post-PHV, n = 88; CON: pre-PHV, n = 44; mid-PHV, n = 15; post-PHV, n = 54). Participants performed 3 reps of 10- and 20-m sprint, bilateral vertical countermovement jump (BV CMJ), and bilateral horizontal-forward CMJ (BH CMJ). Elite youth soccer players demonstrated faster 10-m (p < 0.001) and 20-m sprint (p < 0.001) performance than CON at all stages of maturation. Mid-PHV and post-PHV ESP achieved greater BV CMJ height (p < 0.001) and BH CMJ distance (ESP vs. CON; mid-PHV: 164.32 ± 12.75 vs. 136.53 ± 21.96 cm; post-PHV: 197.57 ± 17.05 vs. 168.06 ± 18.50 cm; p < 0.001) compared with CON, but there was no difference in BV or BH CMJ between pre-PHV ESP and CON. Although 10 and 20 m and sprint performance may be determinants of elite soccer playing status at all stages of maturation, horizontal-forward and vertical jumping capabilities only discriminate ESP from CON participants at mid- and post-PHV. Our data therefore suggest that soccer talent identification protocols should include sprint, but not jump assessments in pre-PHV players.

We investigated the association of multiple single nucleotide polymorphisms (SNPs) with athlete status and power/speed performance in elite male youth soccer players (ESP) and control participants (CON) at different stages of maturity. ESP (n = 535; aged 8-23 years) and CON (n = 151; aged 9-26 years) were genotyped for 10 SNPs and grouped according to years from predicted peak-height-velocity (PHV), i.e. pre-or post-PHV, to determine maturity status. Participants performed bilateral vertical countermovement jumps, bilateral horizontal-forward countermovement jumps, 20m sprints and modified 505-agility tests. Compared to CON, pre-PHV ESP demonstrated a higher ACTN3 (rs1815739) XX ('endurance') genotype frequency distribution, while post-PHV ESP revealed a higher frequency distribution of the PPARA (rs4253778) C-allele, AGT (rs699) GG genotype and NOS3 (rs2070744) T-allele ('power' genotypes/alleles). BDNF (rs6265) CC, COL5A1 (rs12722) CC and NOS3 TT homozygotes sprinted quicker than A-allele carriers, CT heterozygotes and CC homozygotes, respectively. COL2A1 (rs2070739) CC and AMPD1 (rs17602729) GG homozygotes sprinted faster than their respective minor allele carrier counterparts in CON and pre-PHV ESP, respectively. BDNF CC homozygotes jumped further than T-allele carriers, while ESP COL5A1 CC homozygotes jumped higher than TT homozygotes. To conclude, we have shown for the first time that pre-and post-PHV ESP have distinct genetic profiles, with pre-PHV ESP more suited for endurance, and post-PHV ESP for power and speed (the latter phenotypes being crucial attributes for post-PHV ESP). We have also demonstrated that power, acceleration and sprint performance were associated with five SNPs, both individually and in combination, possibly by influencing muscle size and neuromuscular activation.

We have shown that UH, UV and UM CMJs assess distinct lower-limb muscular power capabilities in soccer players. Furthermore, as elite players outperformed non-elite players during unilateral but not BV CMJs, unilateral CMJs in different directions should be included in soccer-specific muscular power assessment and talent identification protocols, rather than the BV CMJ.