Combined landing, core, and jump training modifies lower extremity energetics during single-leg landing in college handball players: Implications for anterior cruciate ligament injury prevention
Non-contact anterior cruciate ligament (ACL) injuries are known to be more common in female than in male athletes, such as handball players who frequently perform sudden decelerationacceleration motions; these athletes are at high risk for such injuries.
Objectives: To examine the effects of combined landing, core, and jump training on lower extremity energy absorption during single-leg landing and to determine the risk of non-contact ACL injury in female handball players.
Settings: Training facilities and laboratories.
Patients or Other Participants: Twenty-three Japanese female division I college handball players(age, 20.0 ± 0.8years;height, 162.4 ± 4.9cm, and weight, 59.1 ± 5.7kg).
Intervention: The subjects participated in a 5-month training program of core and jumplanding training for 1 month and highintensity core, jump-landing, and jump training for 4 months. Before and after the training period, 3-dimensional biomechanical data were collected using electromagnetic motion tracking system and a force plate while subjects performed single-leg landings from a 30-cm box.
Main Outcome Measures: Biomechanical data were collected from non-takeoff (NTOL) and takeoff legs (TOL) when shooting a handball. The negative work (J) of the sagittal plane hip(HW), knee(KW), and ankle joint(AW)during the descending phase of single-leg landings were calculated. A two-way (joint × training) repeated measures ANOVA examined differences before and after training. If a significant interaction was observed, a paired sample t-test was used to determine the difference in work for each joint.
Results: The ANOVA revealed a significant increase in the negative work performed by each joint (pre-training vs post-training: NTOL=-60.2±54.0 vs.-68.2±33.5, p<0.05; TOL=-62.4±39.6 vs. -72.3±24.9, p<0.01) and interactions for both legs(p < 0.01). The paired sample t-test revealed a significant increase in HW(NTOL=-3.4±16.5 vs. -52.4±28.1, p<0.01; TOL=-23.1±21.0 vs.-67.8±24.8, p < 0.01)and a reduction in KW(NTOL=-123.2±29.1 vs.-103.6±20.4, p=0.01; TOL= -101.8±23.1 vs.-86.0±20.2, p<0.05) for both legs. No significant changes in AW were observed (NTOL= -54.0±17.4 vs.-48.5±17.0; TOL= -66.7±20.6 vs.-62.0±19.3, both p>0.05)
Conclusions: HW was lowest and KW greatest during singleleg landing before training. However, a significant increase in HW and decrease in KW were observed after training. Thus, combined training may decrease the possibility of excessive quadriceps muscle activations without hamstring muscle co-activations during decelerating moves such as single-leg landing, which have been suggested to reduce knee stability and increase ACL strain and injury risk.
© Copyright 2013 Journal of Athletic Training. National Athletic Trainers' Association. All rights reserved.
|Subjects:||handball female biomechanics injury prevention knee ligament|
|Notations:||biological and medical sciences sport games|
|Published in:||Journal of Athletic Training|