Changes in tactical behavior during small-sided and conditioned games performed within a training session

Abstract This study aimed to verify the acute effects of 3vs.3 soccer small-sided and conditioned games (SSCG) on the tactical behavior of youth soccer athletes within one training session. Twenty-four soccer athletes (U-13 and U-14 categories) from a professional club participated in the study. They played four 4-minute 3vs.3 SSCG with 4 minutes of passive recovery in-between. All SSCG were recorded and players’ tactical behavior was analyzed using the System of Tactical Assessment in Soccer. We compared the frequencies and percentages of successful tactical principles over the four 3vs.3 SSCG bouts performed within the training session. Results showed an increased number of defensive unity actions (p= 0.005; large effect size) and a higher percentage of successful defensive principles (p