Article Review: by Kira Zarzuela, SPT, Tyler Tice, PT, DPT, OCS


Patellar tendinopathy (PT) is a common chronic tendon injury that not only effects a high percentage of the athletic population, but also a number of people that participate in physically demanding work. Currently, there is no known direct cause of PT, making it difficult to determine first-line treatment as not all people respond the same way to the same treatments. Eccentric exercise therapy (EET) is one line of treatment that has strong evidence supporting its effectiveness for PT, however, EET can be pain-provoking. Additionally, the onset of pain with this mode of treatment makes its use debatable during the competitive season for athletes as they are less likely to adhere to treatment. Recent research proposes the utilization of progressive tendon-loading exercises (PTLE) within the limits of “acceptable” pain, however, there is no current comparison between EET and PTLE. This study compares the effectiveness of PTLE with EET in patients with PT.


This study looked at 76 recreational, competitive, and professional athletes with clinically diagnoses and ultrasound-confirmed PT that were randomly assigned to receive either EET (control group) or PTLE (intervention group) for 24 weeks. Most participants (82%) had previously underwent treatment for PT but failed to recover fully. PTLE consisted of 4 stages: 1. daily isometric exercises, 2. isometric and isotonic exercises, 3. plyometric loading and running exercises, and 4. sport-specific exercises. Progression through these stages was determined by individual progression criteria based on pain provocation during a single-leg squat. EET consisted of 2 stages: eccentric exercises performed 2x/day for 12 weeks followed by sport-specific exercises for 12 weeks if the participant was compliant to stage 1. Both groups received exercises targeting risk factors for PT such as flexibility exercises and hip strengthening exercises.

Outcome measures:

The primary outcome was the VISA-P questionnaire. Secondary outcomes were return to sport rate, subjective patient satisfaction, and exercise adherence.


The improvement in VISA-P score was significantly better for PTLE than for EET after 24 weeks (28 points vs. 18 points).
There was a trend towards a higher return to sports rate in the PTLE group (43% vs. 27%).
The percentage of patients with an excellent satisfaction was significantly higher in the PTLE group (38%) than in the EET group (10%).
There was no significant difference between subjective patient satisfaction and exercise adherence between the PTLE and EET groups after 24 weeks.


This study demonstrated improved performance in the PTLE group compared to the EET group that was both important and clinically relevant. Additionally, as this study included participants who had received prior treatment for PT but did not improve, the findings of this study also indicate that PTLE is still beneficial to this population. Other findings from the PTLE group are that there was a higher return to sports rate compared to the EET group and participants in the PTLE group reported that the exercises were significantly less painful to perform. However, it should be noted that in the PTLE group, less than half of the patients returned to sports at a preinjury level after performing PTLE for 24 weeks. This indicates the need for further improvements on the PTLE program. Both groups demonstrated improvements in pain, function, and ability to play sports, suggesting the importance of exercise therapy in general as a form of conservative management for patients with PT.

Take Home Messages:

Patellar tendinopathy is a chronic condition that affects a large number of people, however there is constant research being conducted to investigate what forms of conservative treatment are the best to trial prior to more invasive procedures. At the time this study was conducted, eccentric exercise training, or training done where the muscle is loaded during the phase where its length is increasing, had strong evidence supporting the effectiveness in PT. The difficult part regarding EET is that it is pain-provoking and its beneficial use during a competitive season for an athlete was uncertain. Another challenge of PT is that one treatment doesn’t work for all patients diagnosed with PT, resulting in several patients having gone through an unsuccessful bout of physical therapy, which only adds to the frustration surrounding the rehabilitation process. This study demonstrated that progressive tendon loading not only worked the same, if not better, than EET and was less pain-provoking, but also was successful in participants who had gone through unsuccessful bouts of treatment for their PT. For clinicians, this means that utilization of progressive tendon loading should be trialed in patients with longer-standing PT or previously failed bouts of treatment. For patients, this means progressive tendon loading is worth trialing, regardless of chronicity or history of treatment, as a form of treatment for PT.

Article Reference:

Breda, S. J., Oei, E., Zwerver, J., Visser, E., Waarsing, E., Krestin, G. P., & de Vos, R. J. (2021). Effectiveness of progressive tendon-loading exercise therapy in patients with patellar tendinopathy: a randomised clinical trial. British journal of sports medicine55(9), 501–509.