## 3 Results
### Key Findings
#### 3.3.3 Non Specified Achilles Tendinopathy  
The authors of the other 26 studies did not specifically write which type of AT they investigated [28; 35; 36; 37; 38; 38; 46; 47; 50; 54; 57; 59; 56; 57; 58; 59; 60; 61; 62; 63; 64; 65; 66; 67; 68; 69; 71; 72; 74; 75; 86]. After patients with AT executed the ECC exercise program, the results showed a significant decrease in pain [28; 35; 36; 46; 47; 59; 63; 71; 72], and an improvement in function [35; 36; 47; 63; 71; 72] and patient satisfaction [36; 46; 47; 63; 71; 72], which was able to be observed up to 4 years after the intervention ended [35]. It was found that, most likely as a consequence of ECC exercise, neither the decrease in pain nor the improvement in function or greater patient satisfaction were associated with a decrease in tendon diameter, a decrease in tendon neovascularization, [47] or a decrease in tendon thickness [48]. On the other hand, the decrease in pain or improvement in function, caused by ECC exercise, were associated with a decrease in tendon volume in the short term, while it was not the case in the long term [47]. The ECC exercise treatment facilitated tendon remodelling by promoting collagen fibre cross-link formation within the tendon [28]. ECC exercise was also found to enhance healthy tissue tolerance and caused positive changes in nervous system sensitization rather than causing dysfunctional tissue or degeneration [28], but it did not reduce the incidence of injury for patients with AT [54]. The pain-free HECT protocol for treating AT was found to be similar or superior in terms of function improvement, pain decrease [62; 71; 75], and jumping performance improvement compared to the classic, painful HECT protocol [71]. Meanwhile, the authors [46; 71] reported contradictory data about the importance of specified intensity. While [PERSON] et al. [71] reported that a similar pain decrease and function improvement were observed regardless of intensity and frequency (either low or high) of ECC exercise, [PERSON] and [PERSON] [46] claimed that a minimum intensity above 79% of the maximum is required to cause adaptations in tendon properties, and material, mechanical, and morphological tendon changes. Intensity probably needs to be greater than 79% of the maximum, while a greater increase in the intensity (up to 100%) does not cause greater improvements. A greater improvement in function for patients with AT was found after daily execution of a home-based exercise program compared to the results obtained after supervised training twice per week [62]. Gradually increasing the load used in the ECC exercise program also caused a superior pain decrease and function improvement compared to predetermined ECC exercise loads [75]. Regardless of the great effects caused by ECC exercise, 45% of patients with AT were not found to have decreased pain or improved function after executing that kind of rehabilitation protocol [46]. ECC exercise was found to be superior in decreasing pain [28; 35; 36; 46; 59; 63; 71; 72], improving function [28; 36; 46; 72], and causing greater patient satisfaction compared to CON exercise for patients with AT [46; 63; 71]. Neither CON exercise as a monotherapy nor the combined CON exercise and ultrasound therapy protocol caused a successful pain decrease and function improvement compared with ECC exercise alone [72]. A significantly greater decrease in pain after executing ECC exercise compared to CON exercise was observed at each of the 4-, 8-, and 12-week follow-ups [59; 71]. After executing a 12-week ECC exercise protocol, the physiotherapists' observed a mean decrease in pain in patients with an AT population of 60%, while the mean decrease in pain after executing a 12-week CON exercise was approximately 33% [67]. ECC exercise also greatly stimulated collagen synthesis compared to CON exercise, but there was no difference between both protocols in the rate of collagen degradation and increase in strength [63].