Injury Prevention Strategies for the Lower Extremity
The Importance of a Dynamic Warmup for Preventing Injury
The ankle and knee are the two most commonly injured joints in the body for young athletes.1 Serious injuries, like those to the ACL, can be costly and withhold young athletes from play for long periods.1 They can also predispose young athletes to additional future leg injuries if they do not recover fully or take steps to prevent future injury.2,4,5 While not all leg injuries are preventable, athletes can employ strategies like a dynamic warm-up routine to lower their risk of injury in order to stay healthy and on the field.
Preventable Risk Factors for Leg Injuries
Alignment: Research has shown that the majority of serious knee injuries occur without contact with another player. Most non-contact knee injuries occur when the knee collapses in or out during powerful movements like jumping or cutting, placing excessive stress on the ligaments supporting the knee.1,2,4,5 Performing a dynamic warm-up can help prepare the body for these powerful movements and over time can improve young athlete’s mechanics making them less likely to injure themselves.3,6
Fatigue: When fatigued, athlete’s coordination as well as their muscles’ ability to stabilize the body is reduced putting them more at risk for injury.2,4,5 The majority of serious leg injuries occur during the second half of competition and they also tend to occur late in the season after an athlete has grown fatigued. Several studies have shown a dynamic warm-up program can reduce overall leg injuries by 50% and overuse injuries by as much as 55% likely by allowing athlete to maintain good mechanics when they are fatigued.3
Previous knee injury: Athletes with previous knee injury or dysfunction are more likely to experience a serious knee injury in the future to either leg.2,4,5,6 It is important to ensure young athletes receive appropriate medical and rehabilitative care following a leg injury to diminish its residual effects and guide return to sport. A dynamic warm-up can help previously injured athletes who return to sports maintain their physical resiliency after leaving rehabilitation while preparing for their sport as well.
What is a Dynamic Warm-up?
Stretching has long been utilized as a warm-up strategy to prevent injury but a growing body of research suggests stretching alone is not adequate to prepare young athletes for the demands of most sports. A dynamic warm-up is a series of exercises, stretches, and drills performed in an increasing intensity meant to ideally prepare the body for high intensity physical activity.
Why Perform a Dynamic Warm-up?
Rather than just loosen tight muscles, a dynamic warm-up can help activate the body’s stabilizing muscles as well as the body’s energy and movement systems, “waking them up” to meet the demands of the upcoming exercise. A number of dynamic warm-ups have been shown to improve performance and reduce the risk of leg injuries but many variations exist and can be effective.3
Basics of a Dynamic Warm-up3
1. Get the Heart Rate Up
To start any warm-up, athletes should increase their heart rate over the course of 5-10 minutes to starting prepping their cardiovascular system and muscles for the upcoming activity. General aerobic exercises like low-moderate intensity jogging can be performed anywhere with a whole team at once making it a good option for most sports.
2. Get Your Core Activated
The muscles that stabilize our spine are primarily located between our shoulders and our hips in what is frequently called the “core”. Performing 3-5 core exercises prior to more intense movements can be beneficial in activating athlete’s core, preparing them to keep their spine, shoulders, and hips stable while playing. This can help reduce injury and improve performance.
3. Stretch while Moving
It is most beneficial to perform stretches dynamically (while moving) rather than sitting still. This involves athletes performing controlled motions into and out of lengthened positions in an effort to loosen stiff muscles and prepare the body for the movements it will need to perform during sport.
4. Practice Jumping and Landing
Plyometrics are rapid, powerful movements that use the elastic energy of our muscles. These include running, jumping, cutting and a variety of other intense movements that occur frequently during sports. Performing jumping, landing, and cutting drills within a warm up has been shown to improve performance and reduce the risk of leg injuries.3
5. Sport Specific Drills
After gradually increasing the intensity of the warm-up, athlete’s bodies will be appropriately prepared to meet the physical demands of their sport. The final part of a dynamic warm-up should include sport specific drills done for short periods of time at a higher intensity. These drills give athletes a chance to practice sport skills in a fully prepared state honing their motor control.
1. Alentorn-geli E, Myer GD, Silvers HJ, et al. Prevention of non-contact anterior cruciate ligament injuries in soccer players. Part 1: Mechanisms of injury and underlying risk factors. Knee Surg Sports Traumatol Arthrosc. 2009;17(7):705-29.
2. Anderson MJ, Browning WM, Urband CE, Kluczynski MA, Bisson LJ. A Systematic Summary of Systematic Reviews on the Topic of the Anterior Cruciate Ligament. Orthop J Sports Med. 2016;4(3):2325967116634074.
3. Herman K, Barton C, Malliaras P, Morrissey D. The effectiveness of neuromuscular warm-up strategies, that require no additional equipment, for preventing lower limb injuries during sports participation: a systematic review. BMC Med. 2012;10:75.
4.Joseph AM, Collins CL, Henke NM, Yard EE, Fields SK, Comstock RD. A multisport epidemiologic comparison of anterior cruciate ligament injuries in high school athletics. J Athl Train. 2013;48(6):810-7.
5. Maletis GB, Chen J, Inacio MC, Funahashi TT. Age-Related Risk Factors for Revision Anterior Cruciate Ligament Reconstruction: A Cohort Study of 21,304 Patients From the Kaiser Permanente Anterior Cruciate Ligament Registry. Am J Sports Med. 2016;44(2):331-
6.Moksnes H, Grindem H. Prevention and rehabilitation of paediatric anterior cruciate ligament injuries. Knee Surg Sports Traumatol Arthrosc. 2016;24(3):730-6.
7. Immermann, Alex. In- Service: Injury prevention. March 2017. EXOS Physical Therapy. Frisco, TX.
Brittani Cookinham, PT, DPT, ATC, LAT
Is the Physical Therapy Manager at EXOS, a sports training facility in Frisco, Texas, and a United States Olympic team sports medicine volunteer. She attended Sacred Heart University where she obtained her Bachelors of Science in Athletic Training and her Doctorate in Physical Therapy.