The Effect of External Focus Versus Internal Focus Instruction on Jump-Landing Biomechanics in Healthy Females.

Context: There are different ways to deliver external focus (EF) and internal focus (IF) instruction. Understanding each modality better will help to develop more effective interventions to reduce injury risk.

Objectives: To investigate the difference in landing biomechanics between participants who received EF and IF instruction and control participants. A secondary aim was to evaluate participant perceptions of focus of attention.

Design: Randomized controlled trial.

Setting: Laboratory.

Patients or other participants: Forty-one healthy women (EF: n = 14, 23.0 ± 2.9 years, 1.69 ± 0.07 m, 64.0 ± 6.8 kg; IF: n = 15, 22.9 ± 3.2 years, 1.66 ± 0.08 m, 66.2 ± 12.4 kg; control: n = 12, 21.1 ± 2.9 years, 1.67 ± 0.11 m, 74.3 ± 15.1 kg).

Main outcome measure(s): Participants scoring greater than or equal to 5 on the Landing Error Scoring System were allocated into the EF, IF, or control group. Knee and hip flexion and abduction were collected pre- and postintervention during 5 drop vertical jumps. For the intervention, each group was provided separate instructions. In between the intervention jumps, participants answered, "What strategy were you focusing on when completing the previous jump-landing trials?" Postintervention minus preintervention change scores were calculated, and separate 1-way analysis of variance assessments were performed to determine differences in the dependent variables.

Results: Individuals in the EF group had a greater change in hip and knee flexion angles than individuals in the control group. There was no significant difference between the EF and IF groups for any variables. There were no significant differences in frontal plane variables. In the EF group, 71.4% aligned with the instructions given; in the IF group, 80% aligned; and in the control group, 50% aligned.

Conclusions: External focus instruction may not produce immediate changes in movement compared with IF instruction. Hip and knee flexion were greater in the EF group than in the control group but was not better than that in the IF group. Clinicians should provide instructions to patients, but the mode of instruction may not be as critical to see positive biomechanical changes. Patients may not always focus on the instruction being given; therefore, the relationship between instruction and patient experience should be further explored.