Context: Soccer is the most popular junior sport in the world. In junior sports, injury analysis and injury-prevention measures for players, especially those under 12 years of age, are urgently needed. Objective: To prospectively study the incidence, sites, types, and mechanisms of injuries in elementary school-aged junior soccer players during games and practices. Design: Descriptive epidemiology study. Setting: Elementary school-aged junior soccer teams in Nagoya, Japan. Patients or Other Participants: Eighty-nine players in 5 community-based club teams of junior soccer (U-12, age range = 11-12 years
U-11, age range = 10-11 years
U-10, age -10 years). Main Outcome Measure(s): Data on all game and practice injuries for the 2013-2014 season were collected using an injury report form. Injury rates were calculated according to injury site, type, and mechanism. Results: The overall injury rate was 2.59/1000 athlete-hours (AHs). The game injury rate (GIR
6.43/1000 AHs) was higher than the practice injury rate (PIR
1.49/1000 AHs
P&gt
.05). The most common anatomical areas of injury during games and practices were the lower limbs (62.5% and 4.02/1000 AHs versus 38.5% and 0.57/1000 AHs, respectively). Contusions (27.6%, n = 8) were the most frequent type of overall injuries. Most game injuries resulted from body contact (43.8%, 2.81/ 1000 AHs), whereas most practice injuries resulted from other types of contact (53.8%, 0.83/1000 AHs). Conclusions: The GIRs were higher than the PIRs in Japanese junior soccer players. A lower overall PIR suggested that players in the U-12 age group practiced under appropriate conditions. However, the higher GIR in this age category needs to be decreased.