According to ancient Greek mythology, Achilles was the bravest, handsomest, and strongest warrior of the army of Agamemnon in the Trojan War. As a child, Achilles’ mother dipped him in the waters of the River Styx, holding him by his left heel. These waters made him invincible, except for the part of his heel covered by his mother’s hand--rendering that part of mighty Achilles’ body vulnerable.
It’s no wonder that Achilles tendon injuries are one of the most common overuse injuries in athletes! Let’s go over this malady and offer some solutions to make your Achilles the strongest part of your body, unlike that of Achilles himself.
While searching for online advice for your Achilles pain, you may come across several different names for this condition: tendinitis, tendinosis, or tendinopathy. These labels refer to the chronicity of the problem. Tendinitis is used to describe a more acute and short duration problem, while tendinosis and tendinopathy indicate long term tendon injury. Studies on injured tendons often reveal the absence of inflammatory molecules, suggesting that while an athlete may perceive sudden onset of tendon pain, the underlying microtrauma has been accumulating over time prior to reaching the symptomatic threshold. The origin of pain in Achilles Tendinopathy can be the sheath of the tendon, the surrounding soft tissues or nerve structures, the tendon sheath, or perhaps even the calf muscles.
There are also two types of Achilles Tendinopathy, differing in the location of injury: insertional and noninsertional, with noninsertional being more common. Insertional Achilles injuries are closer to the heel, where the Achilles attaches. Noninsertional is located more in the middle portion of the tendon.
Symptoms of Achilles Tendinopathy include tenderness to touch over the tendon, visible redness/swelling of the heel or mid-portion of the tendon, morning stiffness of the ankle, pain and stiffness that resolves with movement, pain with completing a heel raise, and/or pain with stretching the calf muscles.
The general outline for treatment of Achilles Tendon injuries is to first unload the tendon to allow for tissue healing, then progressively load it to encourage tissue remodeling and therefore increase its resilience to strain that occurs with sport. Biomechanical factors, such as limited ankle dorsiflexion, excessive or poor control of pronation, and overuse of the calf muscles for propulsion while running should also be addressed. Resting the tendon alone will not result in resolution of the problem.
The key element of treatment for this problem is progressive loading of the tendon. Strengthening exercises, such as heel raises and their variations, are what cause change at the tissue level and the ultimate resolution of the problem. Research shows that eccentric loading, or the part of a muscle contraction where the muscle is lengthening, and slow, heavy loads are best to achieve this remodeling. Another important element to this treatment is duration and frequency of the program. The variables can be modified on a case by case basis, but 2-3 sets of 10-15 repetitions, once a day for 10-12 weeks is used with good results in current research protocols (1,2). The duration of the program is really important, as this is how long it takes to actually make measurable changes in tissue resistance to stress.
Here is an example of an eccentric loading program, progressing by level of difficulty:
Heel Raises on floor, two up, one down
Heel raises on step, two up one down
Single leg heel raise on floor
Single leg heel raise on step
These exercises should be performed with both the knee straight and bent. Bending the knee further isolates the soleus muscle, which can also be involved in Achilles tendon pain. The progression can be followed with both insertional and noninsertional injuries, however it is suggested that the exercises be completed without stretching into dorsiflexion-- thus it is advised to complete all exercises on the floor and not on a step. As they get easier, you can hold weights or use a machine at the gym that can increase the load.
As aforementioned, it is also important to address other factors that can lead to excessive strain on the Achilles tendon. Improving ankle dorsiflexion, glute strength, single leg balance, and posterior tibialis muscle strength can all be helpful in keeping your Achilles healthy. A Physical Therapist can assess which factors are affecting your injury specifically and offer solutions.
Cheers to healthy Achilles Tendons in the New Year!
Kacy Seynders, PT,DPT
1. Kingma JJ, de Knikker R, Wittink HM, Takken T. Eccentric overload training in patients with chronic Achilles tendinopathy: a systematic review. Br J Sports Med. 2007;41(6):e3.
2. Alfredson H, Pietila T, Jonsson P, Lorentzon R. Heavy-load eccentric calf muscle training for the treatment of chronic Achilles tendinosis. Am J Sports Med. 1998;26(3):360-366.