Achilles Tendonitis


If you are reading this, it may be very possible that you or someone you know may be suffering from achilles pain.  Achilles tendonitis is an overuse condition most often seen in 15-18% of recreational runners (males more than females) between the ages of 35-45 (11). For runners an injury like Achilles tendonitis can force them out of training and competition. However, do not fret because you are not alone and there are ways to manage this. 



The Achilles tendon is the largest and strongest tendon in the body.  It's what connects the gastroc and soleus muscles (calf) to the foot, both the muscle and the tendon form a muscle-tendon unit- and this muscle tendon unit acts like a spring. It stretches and shortens in order to generate force to push us off the ground. So in basic terms, this tendon GETS WORKED when we run, spring, jump.  Lai et al. found that the work of the muscle-tendon-unit of the calf increased from 53%-62% to 74%-75% when subjects transition from jogging to sprinting. Therefore, imagine the stress placed on this tissue when running at race pace for an extended period of time.

In most cases the tendon is able to tolerate this stress, but somewhere down the line some intrinsic and extrinsic factors become overbearing and end up irritating the tendon.

What is Achilles tendonitis?


Achilles tendonitis is essentially the irritation and inflammation of the tendon. It can develop anywhere along the tendon- most commonly at the site of insertion (heel) or right in the middle of the tendon- about 2-6 cm away from the insertion site. At first the pain experienced is felt before and after activity. As the mechanical stress continues to plague the tendon, the pain progresses to being felt during activity as well.  Individuals will also report pain/tenderness when you touch the tendon. The tendon will also become thicker - as the repetitive mechanical stress leads to inflammation of the tissue and leads to fibrosis (thickening). 

What causes Achilles Tendonitis?

If you have been running for a long time and develop pain “out of nowhere”  it usually begins to develop from training errors. Training errors include sudden increase in mileage, increase in intensity, increase in hill training, returning too fast from an extensive break, or a combination of these things. However aside from some training errors – there will also be an influence from intrinsic risk factors you may present with.

Intrinsic Risk Factors:

1.     Limited Ankle Mobility- Dorsiflexion

·      There have been a few studies that demonstrated that individuals with  limited ankle mobility (5), as well as individuals with EXCESSIVE ankle dorsiflexion were both predictors for developing Achilles tendinopathy. (2,10)

·      The individuals that exhibited excessive ankle motion ALSO demonstrates weak plantarflexion (gastroc) power  (push off power), so being BOTH too flexibile and not strong enough may lead to  poor foot and ankle mechanics and therefore place stressed on the achilles tendon. ( 10)

2.     Too much or too little subtalar (midfoot) mobility

·      Researcher Kaufman found that individuals that pronate TOO much or presented with a rigid midfoot  demonstrated an increased risk for developing Achilles tendinopathy (6).

·      When you do not pronate at all, there is less shock absorption throughout the whole foot- leading to stress of all the structures of the foot and ankle.


.     When talking about excessive midfoot mobility / excessive pronation it is due to either muscular power deficits of the posterior tibialis or anatomical make up of the foot (pes planus/ flat foot). You may be asking how pronation can provoke achilles tendinitis, so think of it this way: the whole foot should function as one unit. Therefore if the the mid foot drops when you land it will pull the heel with it. This pull of the heel  (we call it calcaneal eversion) changes the pull of the tendon- creating an increase stress. ( see picture above) 

3.     Weak Gastroc (Calf) 

.     As mentioned earlier, ankle stiffness/excessive mobility in conjunction with weak plantar flexion strength has been linked to increase risk for developing achilles tendonitis. 

.     2006 study found that strength deficits of res that 50.0 N-m (36.87ft-lb : meaning 36 lb of energy/work per displacement of one foot) of the gastroc and soleus where significant predictors or an achilles tendon overuse injury (11). In another study researchers found a  4Nm difference in calf strength between runners with achilles tendonitis and those without (12).  So if you can't push off the ground there is more stretch than recoil, so you are just stretching and stretching that tendon. 

.     Usually individuals with weak calves will have to change the way the push off the ground, and that may be by either rolling off the inside of their big toe ( turning feet out). Just like anything else, excessive faulty movement will eventually lead to tissue irritation. 

 How to Help Yourself

What research says:

1.    Eccentrics

·      There has ben a good amount of evidence to strongly suggest the benefits of eccentric exercises. (1,5,8, 11, 12, 13,14)

·      In most of the research the eccentric exercise program lasted from 6-12 weeks- there was no specifics in bouts or reps but in this case I usually recommend started out lighter and work your way up. If you are running, your are loading and pushing for THOUSANDS of steps, so just doing 5-10 reps is not enough! Should start at 45 reps and then progress the exercises to actual heel raises.

Eccentric Heel Raises: 

PhysioU - Eccentric Heel Raises 

PhysioU - Eccentric Heel Raises 

(1) Stand on a step with both heel hanging of the edge, holding onto the banister- push yourself up with the non-painful foot

(2) Then shift your weight to the affected side- keep heel nice and high and slowly lower down. 

(3) Sets 3x15 1-2 times per day 

(4) Keep pain moderate- if no pain at all - increase the weight by holding onto dumbness, and if the pain is too high ( > 5/10 pain) decrease the weight or repetitions.- (yes expect pain for average 4/10 pain for a few weeks- about 10-12 weeks)

2.    Stretching

·      Research has level II type of evidence of the benefits of stretching compared to Level I evidence to eccentric exercises.

·      There isn’t enough research to 100% support its magical benefits to Achilles tendinopathy, but it works for a lot of people- so it is something to try – especially more so for those who truly demonstrate limited ankle mobility. 

gastroc stretch.JPG

.    Along with stretching the gastroc- what also tends to help is the use of a heel lift- the concept is that the Achilles tendon needs more slack, therefore with a heel lift you are providing just that. 12-15mm heel lifts are recommended.

Standing Gastroc Stretch

(1) Stand in front of wall, with the involved foot back.

(2) Make sure both feet are facing forward.

(3) Keep the back leg/knee straight and lean forward until a stretch is felt in the calf. 

(4) Hold for 30 seconds- this can be multiple times per day. 

3.    Massage of the gastroc and soleus

·      This would occur in CONJUNCTION to stretching.  Look at this an attempt to release any muscle tension which would be followed with a stretch

·      Research shows that soft tissue mobilization of the calf muscles reduced pain and improved ankle mobility in patients with Achilles tendinopathy.

gastro foam roll.JPG

Foam Roll: Gastroc

(1) Sit on the ground, place involved side on top of the roller, and then place the uninvolved leg onto to add pressure 

(2) Lift your hips off the ground and slowly roll the calf up and down the foam roller

(3) Try to relax the muscle- it will be very uncomfortable- try going for bouts of 20-30 seconds for 3 rounds.  



Now as a clinician, usually foot/ankle/knee/hip mechanics all play in role in provoking injury.

I suggest to those who suffer from re-occuring and chronic Achilles pain to consult with a physical therapist, get a thorough evaluation with running gait analyzed .

Little movement impairments, muscle imbalance put together may be the perfect concoction for your injury.




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