ATHLETE PERCEPTIONS AND PHYSICAL PERFORMANCE EFFECTS OF THE FIFA 11 + PROGRAM IN 9-11 YEAR-OLD FEMALE SOCCER PLAYERS: A CLUSTER RANDOMIZED TRIAL.

Background: Strong evidence supports the use of the FIFA 11 + injury risk reduction warm-up program among soccer players, but few studies have investigated its impact on physical performance and movement control in athletes younger than 12 years of age, or the athletes' opinions of participating in the program.

Purpose: The primary purpose of this study was to measure the impact of the FIFA 11 + program on movement control [Landing Error Scoring System (LESS) and Y-Balance test (YBT)], agility, vertical jump (VJ) height, and trunk muscle endurance compared to a standard warm-up in pre-teen female athletes over one indoor soccer season. A secondary purpose was to assess the athletes' tolerance and enjoyment of the program.