Now that we are in the fall ultimate season, it is likely that we will be spending more time playing on artificial turf.  Although there has not been any research on risk of injury in ultimate players on artificial turf, it has been shown that there is an increased risk of Anterior Cruciate Ligament (ACL) injury in football players.  Since ultimate and football share similar field play characteristics, it is important for ultimate players to be aware of the potential for ACL injury.

What is an ACL?

You have four primary ligaments inside and around your knee that help provide stability during motion.   The ACL in particular is deep inside the joint and is responsible for making sure the lower leg (Tibia) does not translate ahead of the thigh (Femur).  Injury of the ACL, like other ligaments, is called a sprain and is graded on 3 levels.  In a Grade 1 sprain, less than 10% of the fibers are torn.  In a Grade 2 sprain (partial tear) over 10% of fibers are torn. Finally, in a Grade 3 sprain (complete tear/rupture) 100% of fibers are torn.  About half of injuries to the ACL also involve injuries to the other structures of the knee (menisci, medial collateral ligament, posterior cruciate ligament). 

Obvious signs of ACL injury and indicators to seek further treatment from a health professional include a popping sound at time of injury, locking or clicking, swelling, bruising, instability, decreased range of motion, and pain.

How can an ACL be injured?

The ligaments of the knee can be injured 2 ways, first through direct contact with another player or the ground and second through a non-contact movement such as planting and twisting, sudden deceleration, or landing from a jump on one foot.  When playing on turf, not only is it more common to be injured, you are also more likely to be injured with the non-contact mechanism.  This is especially seen in females due to biomechanical and possibly hormonal differences.

How can we prevent ACL injuries?

Fortunately, we now know that it is possible to reduce the likelihood of these injuries from happening by using a preventative strengthening routine.  There are a number of ACL prevention protocols available and they all have similar components:

- Overall aerobic conditioning (running all directions – forward, back, side-step, carioca)

- Strengthening of the core (front plank and side plank with leg movements)

- Strengthening of lower limbs (eccentric hamstring exercises, walking lunges)

- Neuromuscular control and balance (single leg squats)

- Plyometrics (hopping and skipping – in place, forward/backward, side to side)

- Sport specific agility training (sprinting with changes of direction)

The success of the prevention protocol is two-pronged.   First, the exercises should be done at least twice per week, preferably during warm-up prior to competition.  Second, it is important that the exercises are performed with optimal technique to ensure maximal benefit.  To have a prevention program designed and taught to you, it is beneficial to seek guidance from a health care practitioner who has experience with treating ultimate players.

Another factor to consider is the choice of footwear.  Different shoe-surface combinations have been shown to put greater strain on the ACL and therefore have more potential for knee injury.  To this date, no research has proven that turf shoes (with a greater number of smaller cleats) reduce injury on artificial playing fields.  However, since theoretically shorter cleats would produce a smaller torque on turf fields, it is likely that turf cleats could reduce injury.  

Dr. Heather Hollman is a Chiropractor at Jointworks Chiropractic and has worked with numerous Ultimate Frisbee players at both recreational and elite levels. Working at Jointworks inspired Heather to take up ultimate herself, and she quickly fell in love with the sport (although her backhand could still use some work ;)

Jointworks Chiropractic takes great pride in their close relationship with the Vancouver Ultimate Frisbee community.  They provide evidence informed personalized care unique to individuals through an integrated and hands on approach.  They offer a variety of services including Active Release TechniquesⓇ, GrastonⓇ Technique, Physical Rehabilitation and Injury Prevention Training, Custom Orthotics, Kinesiotaping, Laser therapy , Registered Massage Therapy, and Acupuncture.