The critical role of daily physical activity (PA) in reducing chronic disease risk factors is now well-established. With the reduced amount of time allocated to physical education at the high school level, providing PA opportunities during after-school hours is essential. After-school sport involvement is an important context during which youth can accrue a substantial proportion of recommended total daily activity (e.g., Burgeson, 2005). However, the amount of PA that is typically obtained during team practice sessions has yet to be delineated. Therefore, the purpose of this study was to quantify the average step count and exercise time accumulated by boys high school soccer players during practice sessions over the course of one season. PA was measured in step counts and exercise time (min.) on three boys high school teams using pedometers (Walk4Life LS-2525). They included one Varsity (V [n = 18]), two Junior Varsity (JV1 [n = 13] and JV2 [n = 16]) teams. Pedometers were worn over 11 team practices during which the coaches employed a Teaching Games for Understanding instructional format. Practice sessions were scheduled for the following length of time: 120 min. (V), 70 min. (JV-1), and 100 min. JV-2). The average step counts accrued per practice session were V 7240.6 (SD=1457.2), JV-1 5485 (943.3), and JV-2 6769.5 (898.1). Exercise time averages were V 59.5 min. (9.3), JV-1 48.8 min. (7.0), and JV-2 56.5 min. (6.3). Steps per minute indexes were V 120.8 (10.9), JV-1 118.5 (9.5), and JV-2 118.8 (8.4). Of the total practice session time, players spent an average of 59.5% (9.3), 63.5% (9.6), and 56.5% (6.3) in PA for V, JV-1, and JV-2, respectively. Based on previous daily step count estimates of HS boys (Wilde et al., 2004), participation in soccer accounted for over half a day's PA. Furthermore, steps per min. of players in this study were higher than those reported by Hannon and Ratliffe (2005). Though speculative, employment of more games-based practice formats may have contributed to the steps per min. rate. Given the relatively short time within which PA was accrued (70 to 120 minutes), it appears that after-school soccer involvement is an important mechanism through which recommended daily PA goals can be reached/maintained. However, more importantly, if schools are to facilitate greater after-school PA/Sport involvement for all students, such opportunities will likely require changes in policies regarding eligibility (e.g., no-cut policies), access to facilities and equipment and supervision.Keyword(s): athletics/sports, high school issues, physical activity