ObjectiveTo assess the effectiveness of heavy eccentric calf training (HECT) in comparison with natural history, traditional physiotherapy, sham interventions or other exercise interventions for improvements in pain and function in mid-portion Achilles tendinopathy.DesignA systematic review and meta-analysis were conducted as per the PRISMA guidelines.Data sourcesPUBMED, CINAHL (Ovid) and CINAHL (EBSCO) were searched from inception until 24 September 2018.Eligibility criteriaRandomised controlled trials comparing HECT to natural history, sham exercise, traditional physiotherapy and other exercise interventions were included. Primary outcome assessing pain and function was the Victorian Institute of Sports Assessment-Achilles.ResultsSeven studies met the inclusion criteria. This review suggests HECT may be superior to both natural history, mean difference (MD) (95% CI) of 20.6 (11.7 to 29.5, one study) and traditional physiotherapy, MD (95% CI) of 17.70 (3.75 to 31.66, two studies). Following removal of one study, at high risk of bias, due to pre-planned sensitivity analysis, this review suggests HECT may be inferior to other exercise interventions, MD (95% CI) of −5.65 (-10.51 to −0.79, three studies). However, this difference is unlikely to be clinically significant.ConclusionCurrent evidence suggests that HECT may be superior to natural history and traditional physiotherapy while HECT may be inferior to other exercise interventions. However, due to methodological limitations, small sample size and a lack of data we are unable to be confident in the results of the estimate of the effect, as the true effect is likely to be substantially different.Systematic review registryPROSPERO registration number: CRD4201804493Protocol referenceThis protocol has been published open access: Murphy M, Travers MJ, Gibson, W. Is heavy eccentric calf training superior to natural history, sham rehabilitation, traditional physiotherapy and other exercise interventions for pain and function in mid-portion Achilles tendinopathy? Systematic Reviews 2018; 7: 58

Introduction: Management of mid-portion Achilles tendinopathy is a challenge for both clinicians and researchers. Alteration in tendon structure, muscle performance and pain processing mechanisms have been suggested as mechanisms driving improvement in pain and function. However, few trials have used consistent outcome measures to track changes in pain and function. Objectives: 1) To identify all outcomes measures used in trials utilizing exercise-based interventions for mid-portion Achilles tendinopathy (AT) that assess self-reported pain and function and to report on the reliability and validity of the identified measures, and 2) Propose measures to optimally assess self-reported pain and function in patients with AT. Design: Literature Review Data Sources: Three major electronic databases were searched from inception until May 2016 for studies using isometric, eccentric or isotonic loading protocols for mid-portion AT. Eligibility Criteria: Randomized and non-randomized trials of isometric, eccentric or isotonic loading in people with mid-portion AT. Results: Forty-six studies were included and all outcome measures assessing self-reported pain and function were extracted. While a variety of outcome measures have been used, few have provided reliability data. There is evidence to suggest that the Victorian Institute of Sports Assessment-Achilles (VISA-A) is the only valid and reliable measure of self-reported pain and function for people with mid-portion AT. No other outcome measures have been validated in mid-portion AT. Conclusion: The VISA-A remains the gold standard for assessing pain and function in mid-portion AT. However, while the validity or reliability of the Numerical Rating Scale (NRS) of pain during a functional task has not been established it may be a better measure of immediate treatment effect.

The improvement in pain and function during rehabilitation suggests future research should be directed toward investigating contributing mechanisms as tendon structure on imaging does not change within 2 weeks and muscular hypertrophy is not seen for at least 4 weeks following the inception of a loading protocol. Systematic Review Registry: PROSPERO registration number: CRD42017062737 ( https://www.crd.york.ac.uk/PROSPERO/display_record.php?RecordID=62737 ).