Have you ever been told you have “tendonitis,” golfer’s elbow, tennis elbow, or jumper’s knee? Tendonitis is a common concern among those who engage in physical activity and sports. However, both the diagnosis and the usual advice for management are often confusing and leave folks struggling to return to their desired activities.
If you’ve been in this situation it is important to understand what’s going on and how to work through the issue towards your goals. In this article we aim to provide clarity on the topic and introduce a practical approach for management.
What are tendons?
Tendons are strips of collagenous connective tissue attaching muscle to bone. They contain living cells called tenocytes, which synthesize a complex matrix full of collagen proteins and other substances. Functionally, tendons absorb and transmit force between muscles and bones in order to facilitate movement at a joint. This helps us move our bodies and apply force to an external resistance like a dumbbell or loaded barbell.
Tendons can adapt in response to mechanical loading similar to skeletal muscles and bones. These adaptations occur over time based on the activity demands placed upon the tissues. We may increase or decrease our capacity to handle future loads depending on the dosage of stimulus compared to our current ability [1,2].
What is tendonitis?
We've transitioned away from using the label tendonitis and instead diagnose "tendionpathy" [3]. This is a general term used to describe changes in a tendon typically relating to pain, reduced tolerance for loading, and microscopic alterations in tissue structure. Tendinopathies typically result from repeated, long-term loading that exceeds the capacity for recovery and adaptation [1]. They can affect the site of attachment to bone (“insertional” tendinopathy), or the middle region of a tendon (“midportion” or “mid-substance” tendinopathy).
The change in language from “tendonitis” to "tendinopathy" was purposeful because the ending “itis” implies the presence of inflammation. Many individuals anecdotally describe painful areas as feeling “inflamed”, however, there is very little tendon inflammation in this scenario. Utilizing the label "tendonitis" leads people to pursue ineffective and unnecessary treatments aimed at decreasing inflammation that isn't actually present. Such interventions include non-steroidal anti-inflammatory drugs (e.g., ibuprofen, naproxen) which are not effective for tendinopathy, or corticosteroid injections which are actually harmful to tendons [2]. It’s important to use correct terminology, because the words used to describe an experience drive people’s expectations and preferred treatments [4-7].
Role of Imaging
When experiencing pain, individuals often want to know whether medical imaging like X-ray, CT, ultrasound, or MRI should be obtained to confirm a diagnosis and guide management. Certain types of imaging can show signs of tendinopathy such as disorganized collagen bundles, tenocyte changes, and increased blood vessel and nerve formation [8]. However, over time we have learned that there is a poor correlation between imaging findings and how a person actually feels and functions. In other words, sometimes we might find significant tendon changes on an ultrasound image, while the person has no symptoms or problems with function in the area. In fact, a tendon’s ability to tolerate load does not seem to be closely related to the presence or degree of tissue changes in the tendon [2].
Even if these alterations are more likely in individuals presenting with symptoms of tendinopathy, they typically do not change rehabilitation recommendations. For this reason, imaging is not typically recommended in the initial evaluation of suspected tendinopathy [2, 9]. We therefore need to establish a management strategy that focuses less on specific tissue-level changes, and more on facilitating the person’s return to desired activities.
Key Management Recommendations:
As a caveat before getting into management recommendations, the majority of research on tendinopathy involves the Achilles and patellar tendons. So we will move forward under the assumption that “a tendon is a tendon,” applying similar general principles of management regardless of the specific tendon involved.
Key Point #1: Rest is NOT recommended
As discussed above, tendons adapt in response to mechanical stimuli based on dosage of activity. If loading is under-dosed or absent altogether, tendons adapt by decreasing their capacity for activity. For this reason, we strongly advise against complete rest for tendinopathy. Even though rest can help individuals avoid experiencing symptoms, a return to activity usually results in a resurgence of symptoms since the capacity for load has been reduced. Ultimately, this results in an even lower threshold before experiencing symptoms upon return to activity. Tendons must therefore be stimulated as part of the recovery process to desired activities.
Key Point #2: Pain will be part of the rehab process
It is important to set expectations early that symptoms will be part of the rehabilitation process. We do not need an individual to be “pain free” before engaging in activity, since pain does not reflect ongoing tissue damage or harm [11-15]. This is another reason complete rest is not recommended [10]. To be clear, however, we do not recommend completely ignoring your experience and pushing forward anyways without making modifications. Even though symptoms will be present in rehab, they should not exceed your individual tolerance level (see figure 1 below). One way of thinking about tolerance is the idea of not feeling debilitated during or after activity, where pain is consistently occupying your mind, or you feel limited in your ability to complete routine daily activities.
The other important expectation for symptoms during rehab is that they will ebb and flow based on numerous life factors beyond just the tendon. This means that an increase in pain with activity does not mean you’ve hurt yourself or made matters worse. Instead, it reflects normal day-to-day fluctuations in tolerance for loading. This can be managed by adjusting the dosage of activity such as the type, volume, or intensity of activity. As you regulate activity based on tolerance, symptoms tend to gradually regress over time, and developing these skills for self-management can be useful in the event that symptoms recur in the future. You can read more on the topic of pain HERE.
Key Point # 3: Full functional recovery from tendinopathy typically takes several months
Another important aspect of setting expectations involves the expected timeline for recovery. Full functional recovery from tendinopathy typically takes several months, and often more. Recognizing and accepting this is important because unrealistic expectations for recovery may drive inappropriate management strategies. For example, an athlete who develops a tendinopathy with two weeks to go before a competition may expect that they can fully resolve the condition before meet day. This is unlikely, and continuing to train with provocative loads will more likely prolong the process. Therefore, it is paramount to understand the expected timeline in order to make wise decisions in the rehab process.
Key Point # 4: You are more than just a tendon
It is important to remember how your thoughts and beliefs can influence your experience and response. People with tendinopathies often have persistent symptoms that wax and wane based on activity demands over time. Incorporating the above coping strategies can help through more symptomatic time periods. There’s no reason to fear or permanently avoid movements, but we also shouldn’t ignore our experience and forge ahead regardless of symptoms.
Altering the dosage of activity or temporarily removing some activities may be appropriate. Many folks dealing with tendinopathies report effects on daily living, work, sleep, loss of self-identity, and frustration with mixed information from healthcare professionals. This can certainly be a frustrating process. However, having a better understanding of the issue along with self-management strategies can help with coping through this process, returning to desired activities, and being prepared for future challenges [21-23].
Programming Recommendations:
There are 4 programming areas to consider when managing tendinopathies:
Modify Loading
Resistance Training
Sport Specificity
Return to Sport (RTS)
A major contributor to the development of tendinopathy is
Repetitive application of excess loads beyond the capacity of the tendon … [9].
An important discussion here is that not all loading is the same. Tendons readily adapt when placed under mechanical tension. They play an essential role in the energy storage and release that is required for sprinting, jumping, change of direction, and plyometrics. We will refer to these as dynamic movements.
In the beginning stages of the rehabilitation process, it is appropriate to take some time away from these dynamic movements to aid with symptom reduction. However, since complete rest is not recommended, we need other forms of loading in order to drive the desired adaptations and load capacity. Modifying loading includes addressing the type, frequency, volume, and intensity of activity. These decisions may vary based on activity demands:
Activity Type: low-magnitude, cyclical loading (cycling, running, swimming) vs. high-magnitude loading such as resistance training (powerlifter, weightlifter, bodybuilder)
Frequency: Describes the number of days per week an activity is completed
Intensity: Describes internal load (subjective perception of difficulty of the activity, RPE) OR external load (resistance applied)
Volume: the number of sets and reps
*Time: can be a component of both volume and intensity.
Two case studies will help illustrate how we might modify these variables:
Case Study #1:
A 40 year old male endurance athlete presents with posterior foot pain with activity that has been ongoing for the past year. He pointed to his distal aspect of the Achilles as the area of symptoms. He noticed symptoms increased significantly right after a marathon last Spring.
He’s been running marathons for a few years but prior to this recent race took a few months off from training due to life circumstances. He stated when returning to running after the lay-off he noticed the beginnings of symptoms but kept running in preparation for the marathon. Afterwards he had increased symptoms with activities of daily living, specifically when walking, going up and down stairs/hills or initiating movement after sitting for some time (around 30 minutes).
He’d like to get back to running again but recently was advised to stop any activities eliciting symptoms. He has not ran in the past 6 weeks. During previous marathon training he was running on average 5 days per week and varied runs based on distance, time, and intensity (heart rate). His primary goal is to return to running ASAP.
Based on this history, we are likely dealing with Achilles tendinopathy. Since the athlete has already stopped running, we can leave this dynamic loading out for the initial phase of rehab. We can plan to re-introduce running after we start seeing improvements of symptoms during rehab exercises, although the starting dosage will be low and progress slowly.
In the meantime, we can start implementing resistance exercises to stimulate adaptation in the affected tendon. Some have argued for always starting with isometric exercises, but with more research we’ve learned that there isn’t a particular mode of muscle contraction that is uniquely beneficial for tendon rehabilitation compared to any other [16-18]. In other words, there are no absolute requirements for exercise prescription in tendinopathy rehab. Rather, we should consider the person’s needs based on prior training history and specificity to their goals or sport-specific demands. Anecdotally, if someone is highly sensitized (e.g., experiencing pain symptoms during routine daily activities in life), then we may begin with isometrics if they are better tolerated as a way to get some initial progress.
Isometric exercises in this case of achilles tendinopathy could involve a statically held calf raise, with or without external resistance in a straight or bent knee position. However, the response and tolerance to isometric exercises in tendinopathy is highly variable. Tolerance is assessed both during the activity (e.g., if symptoms markedly increase) as well as in the aftermath of the training session (e.g., persistent pain at rest the day after the exercise session). One individual may tolerate 15 second holds for 3 sets and experience a reduction in symptoms afterwards, someone else may tolerate 30 second holds for 5 sets with stable symptoms, and someone else may experience marked increases in symptoms with isometric exercises. Poor tolerance for the given prescription would merit modifications of exercise intensity, volume, or selection.
Once a person begins to gain confidence in their ability to load the area and symptoms in daily life activities are beginning to regress, progression to heavier loading (described in the research literature as “Heavy Slow Resistance” training) or eccentric-focused contractions can begin. HSR involves slowing contractions down for both eccentric and concentric. The usual approach involves a six-second contraction, such as a squat with a 3 second lowering phase and 3 second rising phase. An eccentric-focused exercise slows down the portion of the movement where the targeted muscle region lengthens under load. It appears that the amount of time a tendon is placed under tension matters for eliciting tendon-specific adaptations. Either of these approaches may be appropriate, with no clear superiority for one over the other in general, outside of individual preferences [17, 19].
For exercise selection, we typically program a bilateral movement and a single-leg movement. For example, a squat variation plus a split squat, step-ups, or calf raise. The bilateral movement will ensure the “heavy” aspect of HSR is met, whereas the single-leg work will allow for isolation to the painful area. Whether this is meaningful at the tendon level is also debatable, however, anecdotally it does appear to help the person gain confidence in specifically loading the affected area rather than habitually off-loading it to avoid pain. We also typically recommend training that specifically loads the affected area to be scheduled on non-consecutive days, preserving “rest days” in between. This provides time to assess tolerance and to allow for recovery.
After a few weeks of resistance training with a gradual improvement in symptoms, we can slowly reintroduce running. Given the lack of running activity over the prior weeks, it’s a good idea to “start low and go slow”. This involves starting with lower total training volume compared to prior training levels, as well as slower pacing/intensity. If someone has previously been training for marathons, we may begin with a slow 5 km run and assess tolerance. If the person reports back having tolerable symptoms both during activity and in the 1-2 days following the run, then we’ve found our starting point to begin building. However, if the person reports experiencing a significant spike in symptoms during or after activity that is poorly tolerated, then the dose of stress was too high and it would be wise to dial back the next run (e.g., down to 2.5 km) to assess tolerance. We may also begin with a lower frequency of 2x/week and slowly layer in additional days in the following weeks as capacity improves.
There is no perfect way to go about this process, but the key is to find a tolerable starting point for activity. It is essential to keep in mind that the process will involve symptoms, and that improvement will not be perfectly linear; there will likely be setbacks along the way. By the end of this process hopefully we have a better understanding of how to appropriately dose activity, manage fatigue and recovery, and the importance of resistance training long-term. These skills can also aid in future self-management.
Case Study #2:
A 25 year old female powerlifter reports right knee pain ongoing for the past 2 years. Her symptoms recently worsened while prepping for a meet. She reported a considerable increase in intensity of training. She identified symptoms are most noticeable directly below her patella when squatting. She’s familiar with the Tame Pain content and has already reduced her Rate of Perceived Exertion (RPE) and external loading but is still having symptoms. She’s most recently been squatting 3 days per week and has a heavy day, light day, and medium day involving a top set of 3, 8, and 5 respectively. She reported also completing Low Intensity Steady State Cardio (LISS) 2 x / week but this doesn’t seem to affect her knee symptoms.
Given the person’s history and symptom presentation, she is likely experiencing patellar tendinopathy. We need not worry about dynamic loading in this scenario due to the nature of her sport, but she did report completing low-intensity conditioning work. Typically this isn’t a major concern, especially in this scenario since she reports that this activity does not seem to be affected. However, if she reported completing high-intensity conditioning then we’d briefly take away this type of loading in exchange for lower-intensity work. She’s off to a great start with self-managing and simply needs a bit more guidance on managing loading to the area. We could make any of the following changes:
Temporarily reduce the frequency of squat training to 2 x / week
Increase target rep ranges on her higher intensity days (3 and 5)
Add a tempo component for squatting and supplemental squat movements (e.g., 3-0-0 Tempo Squat = 3-second eccentric, no pause, and normal speed concentric)
Add in an isolation exercise (e.g., leg extensions / split squats / step-ups / etc.) for a more direct stimulus to the area with less overall fatigue. These can also be helpful for individuals who spontaneously shift to off-load the symptomatic area (stress-shielding) in their primary movements. For example, shifting to the right during a squat in order to avoid loading a symptomatic left knee tendon.
There isn’t one right answer here; rather, it’s best to select variables to change (multiple changes are typically required), “starting low and going slow”, assessing the response, and repeating this in an iterative fashion.
Often, a primary issue people run into with this process is re-loading too aggressively. This often results from inappropriate expectations for the timeline of recovery (see Key Point #3 above). In an effort to minimize this issue we should track the individual’s subjective reporting while incrementally increasing loading according to recent training and based on tolerance. Based on the timing of the meet, there may need to be a discussion about the appropriateness of competing on the scheduled timeline. In other words, it may be wise to postpone competition given 1) that training for maximal meet performance is likely to exacerbate symptoms and make the rehab process take longer than necessary, and 2) maximum performance may be an unrealistic expectation with symptomatic tendinopathy anyway.
Once we begin making changes, it’s unlikely we will be performing heavy 1-rep efforts during this time and thus the person may lose some of the skill and top-end strength necessary for competition depending on how long it takes for symptoms to get under control. It’s best to approach this discussion collaboratively with the athlete to find the best course of action.
Hopefully seeing the variation and approach in both of these cases helps with understanding how to manage your own situation. One final note on loading recommendations: a common narrative holds that tendinopathy is caused by technique issues (e.g. how someone completes a given movement). A common example is the claim that patellar tendinopathy results from the knees sliding forward in the bottom of a squat. To be clear, knees sliding forward is not an issue to worry oneself with beyond the fundamental goal of maintaining balance in the squat. However, if someone finds they are having knee pain with a particular amount of forward knee travel, then in the beginning stages of the process, minimizing forward knee travel can be an acceptable way to modify the intensity of the load and subsequently control for symptom tolerance. With that said, this should not be interpreted as evidence that forward knee travel is inherently “wrong”, dangerous, or that it should be avoided in general. Rather, it is likely that the dosage of loading placed upon the tendon exceeded capacity at that time, and with appropriate gradual loading and adaptation over time, the tendons can build the capacity and tolerance for loading in that position.
Sport Specificity and Return to Sport
As symptoms regress and the individual’s confidence in their ability to load the area improves, it will become necessary to introduce activities that are specific to the individual’s chosen sport or goal activity. This requires a consideration of what an individual’s sport-specific demands actually are: for example, sprinting, change of direction, cutting, plyometrics, jumping, or other dynamic movements.
A similar “low and slow” approach should be taken during this phase of rehab. Take a basketball player with patellar tendinopathy who has responded well to modified loading and resistance exercises such as squats and lunges. We’ve started re-introducing dynamic loading since his sport requires jumping. We can begin with easy jumping in place by practicing free-throws and progressing to 3-point jump shots over time, or we can implement a more structured exercise progression such as:
Bilateral jumping in place for set time
Single leg jumping in place for set time
Bilateral forward hops (no stipulated height or distance)
Single-leg forward hops
Depth drops
Box jumps
Rebounding box jumps
Max vertical jump
This is not meant as a universal prescription, but rather as a sample progression from less demanding tasks to more demanding sport-specific tasks over time based on tolerance. Specifics of sets and reps will vary based on individual tolerance, but again: the overarching principle is to “start low and go slow”, modifying as needed based on response.
By the time this type of sport-specific progression has been completed, it is likely that a significant amount of time has passed from the athlete’s prior competitive peak. A loss of fitness adaptations has likely occurred during this time, and returning to full competitive loading too soon increases the risk of precipitating recurrent symptoms. For this reason, at the end of this sport-specific activity progression the athlete is essentially prepared for a “pre-season” training period before full return to sport.
Prevention of Tendinopathies
Given how complex and frustrating this issue can be, a common question is: are tendinopathies preventable? Not entirely, although there are ways we can manage training to reduce the risk of developing them. Up until this point we’ve discussed the major risk factor for tendinopathy development is the dosage of loading. However, there is evidence for other variables related to the development of tendinopathy as well. Cardoso et al discuss other risk factors inclusive of the following conditions that are associated with an increased risk of tendinopathy [9]:
Finally, we’ve predominantly focused on education and exercise therapy as the mainstay for helping people cope and work through tendinopathies (for good reason). Another common question is whether there is anything else that can be done to accelerate the rehab process. In short, no.
Many seek out adjunct interventions for pain ranging from stretching, medications (e.g., Ibuprofen, Acetaminophen) injections (e.g. PRP or corticosteroid), massage / IASTM, Kinesio-taping, Dry Needling / Acupuncture, Ultrasound, E-stim, surgery, and many others. Without jumping into the efficacy of passive rehab modalities, this approach misses the mark of addressing the driving factor in tendinopathies (loading) and runs the risk of giving a false sense of confidence in a person’s ability to continue to load the symptomatic area similarly to what led them into their current situation [9]. Cardoso et al has a great summary paragraph on the totality of evidence as it relates to tendinopathy management:
“Current research demonstrates that tendinopathy pathoetiology is complex. Clinical diagnosis is a key with imaging showing poor correlation to pain and function. Complete rest is detrimental to tendon and a supervised gradual loading program is the most evidence-based approach to managing tendon pathology. There has been a surge in the number of adjunct treatments available, most of which have inadequate evidence to back their use. The interplay between pathology and pain and why some pathological tendons develop pain or rupture is unknown.” [9]
Take-home Points:
Neither the presence nor extent of alterations in a tendon dictate loading capacity.
Imaging is not typically warranted for diagnosis.
Rest is not recommended.
Full functional recovery often takes several months or more, thus it is important to maintain an embrace the process approach to self-management.
Symptoms will ebb and flow throughout the process based on a variety of factors beyond the tendon. Poor tolerance for a given prescription merits modifications of exercise intensity, volume, or exercise selection.
Modifying loading involves manipulation of activity, exercise type, frequency, volume, and intensity.
Resistance training is highly recommended during and after rehabilitation. There does not appear to be a uniquely beneficial mode of muscle contraction (e.g., isometric vs. concentric vs. other) that is superior to others.
Sport-specific exercises such as “energy-storage” activities may need to be minimized or de-loaded during the initial stages of rehab, and then gradually reintroduced based on symptoms and tolerance.
Return to Sport defines a stage where you are ready for pre-season practice but not full competition since there is typically a loss in baseline fitness during the rehabilitation process.
Although many are in search of passive treatment options, the supportive evidence remains strongest for exercise management.
Remember, if you are dealing with this situation and in need of assistance, we are happy to help guide the path via remote consultation. Just click the link below - "Get Started".
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