Background The FIFA 11+ program can decrease the rate of injury in athletes. Few studies have investigated the role of compliance and if it is correlated to time loss due to injury during a season.

Objective (1) Analyze how differences in compliance to the FIFA 11+ (IP) program may impact injury rate and (2) how differences in program compliance may impact time loss due to injury.

Design Prospective cohort RCT.

Setting Division I & II Men's Soccer (USA).

Patients (or Participants) Sixty-one Division I and II Men's soccer teams were followed over one competitive season. Injury rates and time loss were analyzed. Twenty-seven teams (N=675 players) served as the intervention group (IG) using the FIFA 11+.

Interventions (or Assessment of Risk Factors) Compliance to the IP program and injuries were collected weekly using a secure internet-based system.

Main Outcome Measurements Compliance, exposure and injuries were recorded in 27 of 61 male soccer teams.

Results There was an overall reduction of injury in the IG by 46.1%; demonstrating the decreased likelihood of being injured (RR =0.54, 95% CI 0.49 to 0.59, p<0.0001, NNT=2.64). Compliance was stratified by utilization consistency: low (LC: 1–19 doses/season), moderate (MC: 20–39 doses/season), or high (HC: >40 doses per season). The average utilization per team was 32.81±12.06 FIFA 11+ sessions. There were 54 injuries in 4 teams reported in the LC group (M=13.5, range 10–19 doses, IR=10.35±2.21), 156 injuries in 14 teams in the MC (M=11.14, range 21–39 doses, IR=8.55±2.46) and 75 injuries in 9 teams in the HC group (M=8.33, range 40–64 doses, IR=6.39±2.71). There was a statistically significant difference reached between compliance and injury rate (p=0.034).

Conclusions When compliance to the IP was high, there was a significant reduction in injury and time loss compared to the MC and LC.