The aim of this investigation was to provide anthropometric, physical and physiological performance characteristics of Tunisian young soccer players and to examine the relationship between selected parameters according to their playing standard position. One hundred under 13 years old (U-13) male soccer players were tested. They were classified according to their playing standard positions (goalkeeper: GK, defender: DF, midfield: MF, and forward: FW). Testing consisted of anthropometric measurements including weight, height, and body mass index, and performance measures of speed (5, 15, and 20 m), agility run (Agility-15 m and Ball-15 m), vertical jumping, ball shooting, and aerobic capacity (Hoff Dribble Test and Yo-Yo intermittent Endurance Run, YYIER). GK were taller and heavier than other players. Significant differences of playing positions for the majority of the physical tests include 20 m sprint, Agility-15 m and Ball-15 m times (all p < .01), as well as squat jump and counter movement jump (all p < .01). In addition, weight was significantly correlated with 20 m sprint (r = .29, p < .01), Agility-15 m (r = .30, p < .01) and Ball-15 m (r = .31, p < .01) times as well as ball shooting speed (r = -.42, p < .01). Multiple regression analyses showed that weight and height were the most significant predictors of 20 m sprint time and the YYIER distance, respectively. In conclusion, performance abilities between positions in young soccer players appear to be different. Anthropometry can discriminate physical capacities and soccer skills providing a scientific rational behind the coaches’ practice of selecting young soccer players.

This study examined the test-retest reliability, validity and external responsiveness of a new multi-change of direction agility test (NMAT) designed for soccer players. Forty-four Tunisian soccer players were recruited and were divided into two groups according to their playing levels (International, n = 21 and National, n = 23). Following familiarization, athletes performed squat jump (SJ), countermovement jump (CMJ), running speed test (5 m and 20 m), 15-m agility run (Agility-15 m), 15-m ball dribbling (Ball-15 m), and NMAT and ball dribbling NMAT (Ball-NMAT) in 2 sessions, 48 h apart. The intraclass correlation coefficient and SEM values were .96 (CI 95%: .94 -.98) and .05 seconds for NMAT and .97 (CI 95%: .94 -.98) and .09 seconds for Ball-NMAT, respectively. The smallest worthwhile changes were greater than their SEM for both NMAT and Ball-NMAT. The MDC 95 values were .15 seconds and .25 seconds for NMAT and Ball-NMAT, respectively. Both NMAT and Ball-NMAT were respectively correlated with Agility-15 m (r = .78; p < .001) and Ball-15 m (r = .81; p < .001). Similarly, significant correlations were observed between both NMAT and Ball-NMAT and leg power and straight sprint (.01 < p < .001). International-level soccer players were better than national-level in all tests including NMAT and Ball-NMAT (.01 < p < .001). The areas under their receiver operator characteristics curve were > .7 (.85; CI 95%: .71 -.94 and .91; CI 95%: .78 -.97 for NMAT and Ball-NMAT, respectively). These results indicated that NMAT provides excellent absolute and relative reliabilities. The NMAT can distinguish soccer athletes of different competitive levels. Thus, the NMAT may be suitable for field assessment of specific agility of soccer players.