Achilles Tendinopathy (painful tendon) is a very common condition seen in active individuals. Achilles tendinopathy is often a result of rapid changes in activity level such as starting a couch to 5k training program, increasing running mileage drastically in a short period of time, or insufficient recovery between bouts of high intensity loading. Once achilles tendinopathy begins it can be extremely frustrating because it tends to feel better after resting, unfortunately it is often worse upon return to activity after periods of rest!
An oversimplification of tendon structure and physiology is that a tendon is mainly composed of collagen protein and water. Research has shown that when we load a tendon with exercise (hiking, running, heel raises, etc.) there is a net decrease in collagen production over the first 24-36 hours following and a net increase in collagen synthesis in the 48-72 hours following, hence the need for appropriate recovery. A healthy tendon is not painful because it lacks sensory nerves. We see infiltration of small blood vessels into a tendon when there is disorder between collagen breakdown and synthesis as the body is trying to heal the tissue. These blood vessels carry small sensory nerves along them resulting in pain that is not present in the healthy tendon tissue. Although a tendon will not be very painful when resting and avoiding aggravating activities, it is often more painful upon return to activity because the muscle gets weak which results in the tendon taking more of the load during activity. Also, a tendon requires cycles of loading to provide a stimulus for collagen production to remodel the painful tendon into healthy tissue over time. Unfortunately tendons take a long time to remodel, on the order of 18-24 months! This does not mean that you will be in pain and unable to perform the activities you enjoy for 2 years, but it does mean that you need to be consistent with a structured loading program once you are pain free to ensure the pain does not return.
While recovering from achilles tendinopathy there is plenty of activity that is green light for you! Also, research shows that a symptom monitoring approach where pain intensity during activity, the evening following activity, and the morning after activity is most effective in guiding what is appropriate for your tendon at that point in recovery. We are not saying we want you to be in pain, but understanding a certain amount of pain is not only allowed during tendon rehabilitation but that it is required to provide enough stimulus for tissue remodeling! If you completely avoid pain it is unlikely that you are doing enough to improve your condition meaning more time away from the things you enjoy doing.
There have been numerous studies focused on identifying how much load the achilles tendon must absorb during certain activities ranging from 1x body weight during cycling to 4x body weight with walking and greater than 12x body weight with running which increases as running speed increases! If you want to get back to running at any pace without pain, you need to build a strong and robust musculotendinous complex. Try this achilles tendon loading progression, aiming to achieve 3 sets of 15 reps with pain less than 3/10 intensity before moving on to the next level. When starting out a loading progression, give yourself 3 full days between sessions to maximize your likelihood of success by matching collagen breakdown and synthesis timelines to your activity. Feel free to keep moving with low level pain activities on your off days such as cycling, rowing, and strength training!
There are a number of treatments your Physical Therapist can perform to help reduce pain and provide you with specific guidance on what is ideal for your body as well as identify any other issues that may have contributed to your symptom onset. If you have any specific questions or do not feel like you are making the progress you want, schedule an appointment with one of our experts at Rise!