The purpose of this study was to develop a sports-specific anaerobic capacity test for soccer players that could be administered on commercial treadmills found in most exercise facilities. The Anaerobic Speed Test (AST) is an anaerobic capacity test on a treadmill, however the testing protocol (20% incline, 214 meter/min) cannot be completed on commercial treadmills because they have a maximum incline setting of 15%. This study newly developed the modified Anaerobic Speed Test (mAST) protocol (15% incline, 244 meter/min) through the use of an ACSM metabolic equation to predict energy expenditure equivalent to that of the AST. Fifteen NCAA Division II male soccer players (mean ± SD, age = 20 ± 1.9 yr; height = 181.3 ± 7.9 cm; weight = 74.8 ± 5.2 kg) participated in this study. Subjects participated in three testing days, one AST trial and two mAST trials all done on separate days, and total run time in seconds was recorded for each trial. Mean AST run times (60.5 ± 10.6) had a significantly positive correlation (p<0.001) with mean trial 1 mAST run times (71.9 ± 9.5). Mean trial 1 mAST run times (71.9 ± 9.5) had a significantly strong, positive correlation (p<0.001) with mean trial 2 mAST run times (75.7±10.2). These findings suggest that the mAST is a valid and reliable measure of anaerobic capacity that is sports-specific to running-type athletes and can be administered on commercial treadmills.