It is also the most common injury in athletes over the age of 40, and - unfortunately - it's a problem which doesn't go away very quickly: Traditional achilles tendinitis treatment (ie, rest, non-steroidal anti-inflammatory drugs, orthotics, cortisone injections, icing, ultrasound, and conventional physical therapy) are not very successful, and about 25 per cent of athletes who suffer from chronic achilles-tendinitis problems end up undergoing surgery.
How can achilles tendinitis be prevented - or cured once it develops? Although everyone seems to agree that calf-muscle strength plays a key role in both the development and resolution of achilles tendon difficulties (functionally strong calf muscles should ease stress on the achilles, lowering the risk of injury or promoting healing), not a single scientific study has been published which actually links calf-strengthening with toughening of the achilles - until now
That deficiency has fortunately been corrected, thanks to some recently published research carried out at the Sports Medicine Unit of the University Hospital of Northern Sweden in Umea, Sweden. There, investigators divided 30 athletes with chronic achilles tendinitis into two groups. One group of 15 received only traditional achilles tendinitis treatment (non-steroidal anti-inflammatory medications, rest, orthotics, shoe changes, cortisone injections, and physical therapy), while 15 others engaged in 'heavy-load eccentric calf-muscle training' (to be explained in a moment). All 30 subjects experienced morning stiffness in one of their achilles tendons (athletes with problems in both tendons were excluded from the study) and suffered from pain while running
The heavy-load eccentric calf-muscle training proceeded as follows: athletes stood on a step, with the front edge of the step touching the soles of the athletes' shoes about one-third of the way from the toes to the heel (so that the heels were basically hovering in mid-air). Body position was upright, legs were straight, and all body weight was supported by the forefeet. The athletes then used their good calf muscle (the one not associated with a hurting achilles) to lift the body upward and plantar flex the ankles, bringing the heels upward while the forefeet remained in contact with the step
Then, the healthy leg and foot were removed from contact with the step, and as the unhealthy leg remained straight the patient slowly lowered the heel of the unsound leg to below the level of the step, eccentrically loading the calf muscle attached to the throbbing achilles tendon. That constituted one rep!
Speed of movement (the velocity with which the heel moved downward) was kept slow throughout the overall training period. Three sets of 15 straight-leg reps were conducted per workout, and there were also three sets of 15 reps performed with the unhealthy leg bent at the knee, to activate a deep-calf muscle called the soleus (when the leg is straight, the well-known gastrocnemius is forced to bear most of the load). These straight-leg and bent-leg series of sets, which really didn't take long to carry out, were performed twice a day, seven days a week, for a total of 12 weeks
The patients experienced calf-muscle soreness during the first few weeks of their exertions, but they stayed with the programme (they did stop any workout in which they felt disabling pain). Initially, the exercises were performed without added weight, but as the athletes grew stronger, they conducted the exercises while wearing backpacks with added weight, starting with just a few pounds and building up to a greater load as strength increased. Once the athletes became really strong, weight machines were used to provide additional resistance
No concentric activity
An extremely interesting aspect of this research was that no concentric work was carried out by the calf muscles attached to the afflicted achilles. Concentric contractions are those in which muscles actually shorten while they are contracting, and of course concentric contractions of the calves would be needed to bring the heels back up above the level of the step and plantar flex the ankles prior to another repetition of the eccentric activity (as you know, eccentric contractions are ones in which muscles elongate while they are contracting, which is exactly what was happening to the athletes' 'unhealthy' calf muscles (ie, the calf muscles attached to the ailing achilles) as their heels dropped below the level of the step
If there was no concentric action by the unhealthy calves, how did the athletes get back into position (with heels above the step) for another eccentric load? Elementary - once the unhealthy calf was eccentrically strained (with heel lowered below the level of the step), the healthy leg was positioned back on the step, and the calf muscles of the healthy leg were used to push the body upward and bring the ankles into plantar flexion again
So what happened to the hurting achilles tendons? Prior to the eccentric training, the runners' 'unhealthy' calf muscles were consid-erably weaker than their healthy ones - both eccentrically and concentrically. However, after 12 weeks of eccentric training, there was no difference in strength, either eccentrically or concentrically, even though no concentric training had been carried out with the 'bad' calves
Illustrating the importance of good calf-muscle strength for allaying achilles problems, the eccentrically trained athletes reduced pain while running (which initially had averaged 81 on a scale of 1 to 100, with 100 being the most-intense-possible pain) to near zero after 12 weeks of training. The best news, however, was that all 15 individuals were back to their normal work schedules, training successfully without further achilles problems. As long as they faithfully performed the eccentric-loading exercises a couple of times per week, they were able to keep their achilles free from serious trouble
The news wasn't nearly so good for the 'control' group of 15 athletes who abstained completely from eccentric training. All 15 had to undergo surgery, and post-surgical recovery was not so pleasant. In contrast to the eccentrically trained athletes, the 15 surgical patients were unable to re-build calf-muscle strength in the afflicted leg - even 24 weeks after surgery (they used traditional physical therapy rather than the eccentric programme). Thus, calf strength in the problem leg remained below calf strength in the normal leg, making future achilles problems on that side of the body more likely
What calf muscles really do
Why was eccentric work so effective at thwarting achilles tendon problems? Although we tend to think that the key function of the calf muscles during running is to provide propulsion during the 'toe-off' portion of the gait cycle (such heel-raising action would be concentric in nature), the truth is that the calf muscles are not even active at that time. Their most important role is to control dorsiflexion of the ankle during the stance phase of running, ie, to prevent the ankle from flexing too much while the foot is planted on the ground, and to prevent abnormal pronation (inward rolling of the foot) during the stance phase of the gait cycle
If you think about it for a moment, you'll realize that such activity is strongly eccentric: once the foot hits the ground, the lower part of the leg comes forward, and the angle between the top of the foot and the shin narrows (producing dorsiflexion of the ankle). This dorsiflexion pulls hard on the achilles tendon and calf muscles (try it in slow motion to see for yourself), elongating them at the exact time the calf muscles are contracting in an attempt to control the collapse of the shin over the top of the foot (that's eccentric!). In addition, the foot rolls inward naturally during the stance phase, twisting and stretching the achilles tendon and its calf muscles, and the calf muscles must contract vigorously to control this inward rolling (eccentric again!)
Excessive dorsiflexion and/or pronation, ie, the inability of the calf muscles to eccentrically control dorsiflexion and pronation (which is the direct result of weak calves), ruins running economy (economy is harmed because energy must be utilized to correct the exorbitant movements) and puts far too much stress on the achilles tendons, leading to achilles tendon injury. Strengthening the calf muscles eccentrically (as in the Swedish research) makes them more forceful during eccentric activity, brings dorsiflexion and pronation under control, takes the pressure off the achilles tendons, and thus prevents Achilles-tendon injury or promotes the healing of hurting achilles tendon.
Walt improves on the Swedes
While the Swedes' eccentric routines worked remarkably well, they're actually not the best exercises for the achilles tendons. As you're probably aware, they work the achilles eccentrically - but in only one plane of motion - the sagittal plane of straight-forward, straight-backward motion. That's not bad, but the truth is that the achilles tendons and calf muscles must move and work in three planes, the sagittal, frontal (side-to-side), and transverse (rotational) planes during running. If they are weak in any one of these planes, injury can result
We can confidently make that statement because the ankles don't work in a squeaky clean, straight-front, straight-back manner when you run. When your ankle pronates during the stance phase of the gait cycle, as almost all ankles do, the foot rolls inward, moving the achilles in a frontal plane (from side to side) and also producing a rotational movement of the achilles (again, try this in slow motion to see for yourself). As the ankle supinates, the achilles again is stressed in both frontal and transverse (rotational) planes, in addition to the well-recognized sagittal plane
That's why Walt Reynolds's Special Achilles Strengthener, which works the achilles in all three key planes of motion (and was also described in issue 88 of Peak Performance, March 1997), actually works better than the Swedish routine. To carry out Walt's SAS, aka the Balance and Eccentric Reach with Toes, start by standing on your right foot only as you face a wall, with your right foot about 30 inches or so from the wall (you may need to adjust this distance slightly). Your left foot should be off the ground and positioned toward the front of your body, with your left leg relatively straight
Then, bend your right leg at the knee while maintaining your upper body in a relatively vertical position and nearly directly over your right foot. As you bend your right leg, move your left toes toward the wall until they touch, keeping the left leg relatively straight. End the movement by returning to the starting position
Then, complete essentially the same motion, but move your left foot forward and to the left, again keeping your left leg straight and attempting to make contact with the wall. Your left foot may not quite reach the wall, since you are moving in a frontal plane (from right to left) in addition to the straight-ahead, sagittal plane. Notice that your right ankle pronates as you do this (ie, rolls inward), simulating the natural pronation which occurs during the stance phase of the gait cycle and forcing your right calf muscles and Achilles tendon to eccentrically control both dorsiflexion and pronation, as they naturally do during real running
Return to the starting position and then carry out essentially the same motion, but with your left foot crossing over the front of your body and going to the right as you attempt to touch the wall. As you do so, your ankle supinates, as it naturally does toward the end of the stance phase of the gait cycle. Then return to the starting position. Do a few (4 to 6) reps (the straight, left, and right motions make one rep) on your right foot, and then attempt the same exercise with your body weight supported only on the left foot and your right foot moving ahead. A nice feature of this exertion is that it also does a great job of strengthening your knee and hip muscles and coordinating their activities with what is happening down at the achilles and calves
Of course, never attempt these exercises unless you have warmed up properly. If you've been prone to achilles tendon problems, here's a good routine to get into: at the very beginning of your workout, warm up
by jogging easily for 10 minutes. Then, carry out the Swedish exercises and Walt's SAS before continuing on with the rest of your session
Obviously, you don't want to throw yourself into these exercises with too much abandon. If you do, you might actually irritate - not help - your Achilles. The idea is to progress from fairly easy achilles routines to very difficult ones, making your achilles tendons and calf muscles progressively stronger as you do so
How do you progress properly? Use slow speeds of movement at first, small ranges of motion (not very much bending at the knee), low resistance (just your body weight), and very few repetitions (only 4 to 6)
Once you're comfortable with doing the exercises in that manner, you can begin incorporating greater speeds, larger ranges of motion at the knees and ankles, heavier resistances (starting with very light dumbbells held in the hands and moving up to heavier ones), and more repetitions (starting with 7 to 10 and gradually moving up to 20 to 30). The idea is to progress in difficulty as you progress in strength and coordination
If you carry out the Swedish manoeuvres and Walt's SAS in a reasonable manner, it's almost impossible to injure yourself. Plus, there's no financial cost involved, and the time required to do the routines is short. So, the next time you have an Achilles-tendon problem, throw those NSAIDs in the rubbish, kiss those painful cortisone shots good-bye, and start using the Swedish and Waltish routines. In a few weeks, you should be back to your regular exercise programme again - with pain-free achilles tendons!