Performance changes after two anaerobic training regimes in soccer players

The aim of this study was to compare the effects of two anaerobic training regimes on highintensity intermittent exercise performance evaluated by the Yo -Yo Intermittent Recovery Test level 1 (YYIR1) and 2 (YYIR2). During a 8-12-wks in-season period, nineteen sub-elite soccer players (age 24\ub15 years, height 177\ub17 cm, body mass 75\ub15 kg) performed either repeated sprint (RS; n=9) or speed endurance production (SEP; n=10) training twice a wk. RS training consisted of 2-4 sets of 6x5-s sprints followed by 10-15 s of passive recovery, whereas SEP training was characterized by 6-8x20-s all-out efforts interspersed with 120 s of passive recovery. After the training period, both RS and SEP group improved significantly YYIR1 (RS: 2236 vs 2480 m; SEP: 2248 vs 2580 m; p<0.001) and YYIR2 (RS: 911 vs 1078 m; SEP: 904 vs 976 m; p