All injuries occurring over a 7-week period at a local indoor soccer arena were documented for analysis of incidence rates. All injury rates were calculated per 100 player-hours. The overall injury rates for male and female players were similar, 5.04 and 5.03, respectively. The lowest injury rate was found among the 19- to 24-year-old athletes and the highest injury rate was found among the oldest age group (> or = 25 years). Collision with another player was the most common activity at the time of injury, accounting for 31% of all injuries. The most common injury types were sprains and muscle contusions, both occurring at a rate of 1.1 injuries per 100 player-hours. Male players suffered a significantly higher rate of ankle ligament injuries compared with female players (1.24 versus 0.43, P < 0.05), while female players suffered a significantly higher rate of knee ligament injuries (0.87 versus 0.29, P < 0.01). Goalkeepers had injury rates (4.2) similar to players in nongoalkeeper positions (4.5).