Samenvatting

External of focus of attention has been shown to result in superior motor performance compared to an internal focus of attention. Adding external focus of attention may optimize current anterior cruciate ligament (ACL) injury prevention programs. Objective: To determine the effect of internal (IF) and external focus (EF) and video instruction (VI) on drop vertical jump (DVJ) landing strategies assessed with landing error scoring system (LESS). Design; Descriptive cohort study. Setting; Controlled laboratory setting. Patients and Other Participants; Forty recreational athletes performed DVJ’s in five sessions: a pretest (baseline measurements), two training blocks (TR1 and TR2), a posttest directly after the training sessions and a retention test one week later. Subjects were randomly assigned to one of the four groups; IF (n=10, ), EF (n=10, ), VI (n=10, ) or the CTRL group (n=10, ), with 5 females and 5 males in each group. 22.60±1.35 years, 1.80±0.14 m, 72.40±10.38 kg Interventions: After a general instruction before pretest, group specific instruction was offered before TR1 and TR2 started and after every 5 trials in TR1 and TR2. The IF group received an instruction regarding attention to the body, the EF group received an instruction directed to the movement effect and the VI group viewed an expert video. Subjects in the IF, EF and VI groups were free to ask for feedback on their real time LESS during TR1 and TR2. Subjects were only aware that a lower LESS score implied a better landing strategy. A 4x5x2 repeated measures ANOVA was conducted to determine differences between groups (IF, EF, VI and CTRL), time (pretest, TR1, TR2, posttest and retention test) and gender (female and male), followed by post hoc comparisons (Bonferroni) with alpha level set at α≤0.05 a priori. Main Outcome Measures: Mean total LESS scores. Results: Males in the VI group had significant lower LESS scores in the post- (1.92±0.27) and retention test (1.72±0.30) compared to the pretest (2.72±0.83).