of the Effectiveness of Anterior Cruciate Ligament Injury Prevention Programme
Training Components: A Systematic Review and Meta-Analysis

Taylor JB, Waxman JP, Richter SJ,
& Schultz SJ. British Journal of
Sports Medicine
.  Epub ahead of print August 8, 2013; doi:10.1136/bjsports-2013-092358

Take Home Message:  ACL prevention programs, that are effective
at reducing ACL injuries when focusing on stretching, strength, and agility
activities, can be done in relatively short warm up periods with little to no
disruption to practice activities.   

Anterior cruciate ligament (ACL)
injury prevention programs have been developed in efforts to decrease the
likelihood that an athlete suffers an injury, especially females.  There are a wide array of programs available,
which has lead to confusion and mixed results. 
The purpose of this meta-analysis was to investigate ACL prevention
program and objectively quantify the duration, points of emphasis, and
effectiveness in female athletes. A literature search yielded 13 studies that met the inclusion criteria: 1)
randomized controlled trial or prospective cohort study, 2) ACL incidence
reported or calculated, 3) included specific exercise descriptions, and 4)
training session durations were reported. 
Overall, the intervention programs reduced the rate of ACL injury.  The duration of a single training session
ranged from 10 to 44 minutes and the programs included 10 to 108 sessions.  However, the authors found that the total
training time (number or duration of training sessions) did not influence ACL
injury rates.  The exercises within each
program were further categorized into 5 areas: strength, explosive, balance,
agility, or stretching.  Most programs
(69%) included strength, explosiveness, and agility exercises, while less
programs included balance exercises (54%) or stretching exercises (23%).  The majority of the programs emphasized
balance and agility exercises.  Overall, ACL
injury risk increased as the duration of balance exercises increased, but
non-contact ACL injuries decreased as the duration of stretching exercises
increased.  A subgroup analysis revealed
no differences between athletes that did or did not receive feedback during the
exercise program.

Clinically, this meta-analysis reveals
that ACL prevention programs reduce the risk of ACL injury in females, and
having an intervention program is more important than duration, number of
sessions, or feedback.  Therefore, we can
offer a short and efficient program to busy coaches and teams that may reduce the
risk of ACL injury.  During this
potentially short and efficient program, we may minimize the time dedicated to balance
training and instead focus on stretching, strengthening, and agility
activities.  While strength and agility exercises
did not significantly influence the rate of ACL injuries, there was a trend suggesting
they may be important.  More research
needs to be done on these activities to determine whether ACL prevention
programs improve strength and/or induce neural adaptations.  Regardless, this meta-analysis demonstrates
that these programs may be short, focused on stretching as well potentially
strength/agility activities, and introduced to a team to do on their own as
part of their warm up.  Coaches may be
able deploy these programs to reduce the risk of ACL injury and not take away precious
time from practice.

Questions for Discussion: Do
you think that we have enough information to potentially develop more efficient
and effective ACL prevention programs?  Do you favor emphasis on a particular
component of training or giving feedback during programs?
by: Nicole Cattano
by: Jeffrey Driban

Related Posts:

Taylor JB, Waxman JP, Richter SJ, & Shultz SJ (2013). Evaluation of the effectiveness of anterior cruciate ligament injury prevention programme training components: a systematic review and meta-analysis. British Journal of Sports Medicine PMID: 23922282