Bulletproof Ankles: Strength And Stability To Prevent Ankle Sprains

Bulletproof Ankles: Strength And Stability To Prevent Ankle Sprains

Ankle Injury Prevalence

According to current research, ankle sprain is the most common injury in sports, accounting for 45 percent of all athletic injuries. The risk of a recurrent ankle sprain doubles in the first year, following injury. Ankle injury can be precipitated by instability of the ankle.

Functional Vs. Mechanical Instability

Functional ankle instability (FAI) is characterized by an ankle that buckles or “gives way” in activity. The causes of FAI include muscle weakness, impaired balance control, delayed muscle reaction time and decrease joint proprioception. Joint proprioception is the joint’s ability to detect the position it is in (this is done by mechanoreceptors) and send that information back to the brain to make adjustments as needed.

Movement beyond the ankle’s normal range of motion is classified as mechanical ankle instability (MAI). This is caused by ligament laxity, anatomical abnormalities, degenerative and chronic inflammatory processes.

Although both forms of ankle instability have different causes, one may compound the effects of the other. Mechanoreceptors in the joints must adapt to the elongation of ligaments, and this will alter joint proprioception. If you feel that your ankles are unstable there is an easy test to determine your risk for ankle sprain.

How To Identify Risk Of Ankle Sprain

The single leg balance test has been proven to be a reliable and valid tool for assessing risk of ankle sprain. In this test, the athlete stands on one foot without shoes—the opposite knee is bent and not allowed to touch the weight bearing leg, hips remain level to the ground, eyes are open and fixed on a point on the wall, then the eyes are closed for 10 seconds. The athlete has failed the test if their bent leg touches the weight bearing leg, if their foot position changes on the floor, if the foot of their bent leg touches the ground, if their arms move from the original position, or if the athlete reports imbalance. If the athlete does not pass the first trial, a second trial is done with only the result of the second trial counting. Both feet must be tested and the athlete must be able to perform the task on both legs in order to avoid failing. If it’s too late for testing and you have sprained your ankle, it’s important to understand the phases of injury to determine when return to activity will be appropriate.

Phases Of Injury

Phase One: Starts at time of injury and ends when all signs of inflammation (pain, loss of function, swelling, redness, heat) have subsided. This phase generally lasts two to four days and is also characterized by scar tissue composition. Goals of treatment in this phase are to protect the injured ankle, control pain, limit swelling.

Phase Two: Repair and regeneration. Starts two to four days after injury and lasts through approximately the sixth week after injury.

Phase Three: Remodeling of tissue. Starts approximately three weeks after injury and lasts a minimum of 12 months to complete.4 Tensile strength of the healing ligament increases during this phase.4

Recovery After Injury

Within 12 weeks following the trauma, 60-90 percent of people will return to activity at their pre-trauma level. With that being said, 40 percent of ankle injuries result in chronic ankle instability and risk of recurrent ankle sprain increases after the first one. Up to 70 percent of patients report persistent residual symptoms

After completion of a proprioceptive training program with our innovative balance board trainer, recurrence of ankle sprain decreases by 50 percent. By just replacing your typical warm-up with a balance exercise board program, you can greatly reduce your risk of future ankle sprain.

How The TherRex Balance Board Can Help

Due to it’s patented shape, the TherRex balance board trainer allows you to exercise your ankle functionally in the plantarflexed and inverted position. Doing so activates the peroneal muscles at up to 100 percent of maximal muscle contraction. Insufficient strength of the peroneal muscles is associated with recurrent ankle sprain and chronic ankle instability—exercise should focus on conditioning these muscles. The principle of specificity dictates training be as closely simulated to the task or activity as possible. Functionally training the ankle in this position can prevent injury and keep you doing what you love. This makes TherRex balance board trainer the best balance board for ankle strengthening, rehabilitation, and injury prevention.

Ankle Exercises

1. Lateral Movement

Rock the board side-to-side. Try to control the board and limit motion front to back.




2. Front-To-Back

Tilt the board front-to-back. Try to control the board and limit motion side-to-side.




3. Lateral Ankle Isolation

Rock the board to one side, then tilt the board front-to-back using foot on same side. This exercise can be progressed by gradually decreasing weight bearing through opposite foot.




4. Full-Depth Heel Raises

Position one or both feet further back on the board, as shown. Raise your heels and tilt the board forward to increase range of motion.




5. Supinated Heel Raises

Position one foot at an angle to the center of the board, as shown. Raise your heel and tilt board forward to increase range of motion.



*This exercise will promote the natural motion of the ankle throughout the movement. It will also increase activation of the ankle everters, an important muscle group for lateral ankle stabilization.



Chad Franche, PT, DPT

Click here for a complete ankle sprain recovery program and get back to pain free activity!

Contact us today to learn more about how the TherRex Board can change the route to recovery and injury prevention for you, your clients, and all athletes.


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