Lowering minimum eye height to increase peak knee and hip flexion during landing

Neuromuscular training programs predominantly include instructions that promote an internal focus

Neuromuscular training programs that include movement pattern retraining and strengthening, plyometric, and balance exercises are recommended for anterior cruciate ligament injury prevention. Recent evidence suggests that the effectiveness of these programs may be enhanced when athletes train with an external focus; however, clinicians typically rely predominantly on instructions encouraging an internal focus. The aim of this study was to examine the types of instructions provided as part of popular neuromuscular training programs used for anterior cruciate ligament injury prevention. The technique-related instructions provided as part of the FIFA 11+, HarmoKnee, Knakontroll, and Prevent Injury and Enhance Performance programs were categorized as either promoting an internal focus or an external focus. Instructions provided during movement pattern retraining tasks and strengthening, plyometric, and balance training exercises were specifically examined. Next, the percentage of technique-related instructions that promoted an internal focus, versus the percentage that promoted an external focus, were compared for the various program components. Across all programs examined, the vast majority of technique-related instructions for the movement pattern re-training tasks (≥83.3%) and the strengthening, balance, and plyometric exercises (≥75.0%) appeared to promote an internal focus. Despite evidence suggesting that the effectiveness of neuromuscular training programs may be enhanced by encouraging an external focus, most technique-related instructions provided as part of popular neuromuscular training programs appear to promote an internal focus. Modifying neuromuscular training programs to promote a more external focus could help to improve the effectiveness of these programs for anterior cruciate ligament injury prevention.

The Effects of Attentional Focus Instructions Specific to Body Movements on Movement Quality and Performance

Contexts: Directing an individual's attention to the effect of the movements (external focus) has been shown to improve performance than directing attention to body movements (internal focus). However, the effect of attentional focus instructions specific to movement quality has not been investigated thoroughly.

OBJECTIVE

To compare the effects of internal and external focus instructions specific to body movements.

DESIGN

Mixed design, 2 (sex) × 2 (instructions).

SETTINGS

Laboratory setting.

PARTICIPANTS

A total of 40 participants (males, n = 20; mean [SD]; age = 22.0 [2.19] y; height = 179.33 [5.90] cm; mass = 77.7 [13.04] kg; females, n = 20; age = 22.0 [3.87] y; height = 164.84 [5.80] cm; mass = 71.48 [20.66] kg) were recruited.

INTERVENTION

Participants completed 2 consecutive jumps (ie, a forward jump from a height and then a maximal vertical jump) with internal focus and external focus instructions. External focus was elicited by placing pieces of tape on the participants' legs.

MAIN OUTCOME MEASURES

Landing quality was measured by the Landing Error Scoring System to assess movement quality, and the vertical jump height was measured by Vertec.

RESULTS

The performance results showed that the external focus condition resulted in superior vertical jump height compared with the internal focus condition (P < .05). Although landing quality did not show significant differences between 2 conditions, the effect size (η2 = .09) indicated that landing quality was better when participants adopted an external, rather than an internal focus of attention (P = .07).

CONCLUSIONS

The body-oriented instructions can be provided externally by adding artificial external cues and directing attention to them. Importantly, the findings were evident in a qualitative assessment that can be adopted by practitioners. The results suggest that practitioners should adopt an external focus cue for performance and also consider using an external focus for movement quality.

The effects of mid-flight whole-body and trunk rotation on landing mechanics: implications for anterior cruciate ligament injuries

The purpose was to quantify the effects of mid-flight whole-body and trunk rotation on knee mechanics in a double-leg landing. Eighteen male and 20 female participants completed a jump-landing-jump task in five conditions: no rotation, testing leg ipsilateral or contralateral (WBRC) to the whole-body rotation direction, and testing leg ipsilateral (TRI) or contralateral to the trunk rotation direction. The WBRC and TRI conditions demonstrated decreased knee flexion and increased knee abduction angles at initial contact (2.6 > Cohen's dz > 0.3) and increased peak vertical ground reaction forces and knee adduction moments during the 100 ms after landing (1.7 > Cohen's dz > 0.3). The TRI condition also showed the greatest knee internal rotation angles at initial contact and peak knee abduction and internal rotation angles and peak knee extension moments during the 100 ms after landing (2.0 > Cohen's dz > 0.5). Whole-body rotation increased contralateral knee loading because of its primary role in decelerating medial-lateral velocities. Trunk rotation resulted in the greatest knee loading for the ipsilateral knee due to weight shifting and mechanical coupling between the trunk and lower extremities. These findings may help understand altered trunk motion in anterior cruciate ligament injuries.