Effectiveness of a 12-week self-myofascial release therapy on pain and tendon stiffness in active recreational runners with self-reported Achilles tendon complaints

Running is a popular sports activity that triggers a variety of health benefits
(Hespanhol Junior et al. 2015; Lee et al. 2014; Chakravarty et al. 2008).
Although outweighing the risks in most cases, its positive effects are
compromised by the burden stemming from running-related injuries (RRI). The
incidence of RRIs in recreational runners is about 7.7 RRIs per 1,000 hours of
running (Videbaek et al. 2015). Achilles tendinopathy (AT), is one of the most
common disorders among professional and recreational runners (Kujala et al.
2005; Lopes et al. 2012), accounting for about 9% to 15% of all RRIs in Dutch
runners (Hespanhol Junior et al. 2016; Hespanhol Junior, van Mechelen and
Verhagen 2016). It is thought to develop due to overuse with several other risk
factors, and brings with it a risk of becoming chronic (Järvinen et al. 2005.).
Symptoms consist of pain, morning stiffness and tenderness to palpation, while
at least one of the symptoms has to have been apparent for at least 3 months
(Kraemer et al. 2012.). There seems to be a pathological continuum from a
healthy Achilles tendon to AT (Kraemer et al. 2012), which in turn represents a
risk factor for tendon rupture (Järvinen et al. 2005). This suggests that by
treating complaints such as pain or stiffness of the Achilles tendon as early
as possible, the progression into chronic symptoms and further degeneration
could possibly be prevented.

A plethora of non-pharmaceutical treatments mainly targeting the Achilles
tendon and the calf muscles have been proposed to ease the symptoms.
Anatomically, the Achilles tendon does not only fuse with the calf muscles but
also displays a fibrous continuity to the plantar aponeurosis (Wilke et al.
2016a). Albeit not necessarily linked to the pathology, the finding of a
thickened plantar aponeurosis in patients with Achilles tendinopathy underpins
this paradigm (Stecco et al. 2013). A lot of times the same treatments that
have shown to be effective for mid portion Achilles tendinopathy are prescribed
for insertional Achilles tendinopathy. This is being done despite lack of prove
that it is effective for this specific origin of the problem. It is known that
aetiology, injury mechanism, treatment and rehabilitation differ between the
two pathologies (Wiegerinck et al. 2013). This implies that multifocal
approaches might open new frontiers. Tackling dysfunctions of aponeurosis,
tendon, and calf muscles might hence be more effective than interventions
limited to one structure only. Furthermore, if effective, they could prove
more practical to prescribe in case of lack of clarity about the exact origin
of the complaints, or in case of more than one origins of symptoms in the same
Achilles tendon.

Eccentric exercise (ECC) has proven to represent an effective and safe
conservative treatment for Achilles tendinopathy (Malliaras et al. 2013;
Alfredson and Lorentzon 2000). One of the main advantages of this method is
that patients can be instructed by a physiotherapist or exercise therapist to
perform the exercises without supervision (Rompe, Furia and Maffulli 2009;
Alfredson et al. 1998). However, as the exercises require muscular contraction,
it is unable to directly target the plantar aponeurosis. Like ECC,
self-myofascial release (SMR) can also be performed in a home-based setting.
SMR claims to mimic the effects of manual therapy and might thus operate
through similar mechanisms as ECC, which has been suggested to stimulate
collagen I production and reverse pathological neovascularization (Ohberg and
Alfredson 2004, Langberg et al. 2006). Moreover, although evidence is scarce so
far, SMR has been described to loosen fascial adhesions and cross-links,
increase the gliding capacities of connective tissue layers, decrease muscle
tension and to alter mechanical stiffness. SMR does not impede athletic
performance (Beardsley und ¦karabot 2015). It has also been suggested that SMR
might have, as all manual therapies, a potentially pain-relieving effect. These
analgesic effects may be mediated by either peripheral, spinal or supra-spinal
mechanisms (Bialosky et al. 2009.). All of the above mentioned processes might
help to restore physiological tendon function. We found only 3 studies
examining the effect of SMR on the calves, none of which specifically target to
measure the effect on pain and tendon stiffness after a period with regular
interventions (Halperin et al. 2014, Healey et al. 2014, Peacock et al. 2015).

The purpose of this study will be to evaluate and compare the effectiveness of
a multifocal SMR treatment on pain and stiffness compared to ECC in active
recreational runners with self-reported Achilles tendon complaints.

Research question: Is a 12-week multifocal SMR treatment more effective in
treating self-reported Achilles tendon complaints than ECC in active
recreational runners?

This study is designed as a two-armed, single-blind, randomised controlled
trial that will be conducted in accordance with the declaration of Helsinki and
adhering to the CONSORT guidelines. Each subject will provide informed consent
before inclusion. After a baseline measurement of subjective complaints and
mechanical pain threshold the included participants will be randomly allocated
(1:1) to an intervention group (i.e., SMR) and an active control group (i.e.,
ECC). Randomization will be stratified based on average running exposure
(whether or not subjects run more or less than 5 hours per week). The outcome
measures will be assessed again 12 weeks after baseline measurements.
Additionally, running exposure, pain, adherence to the treatment, and competing
interventions will be assessed every week throughout the 12-week treatment
period through an online-log.

All subjects will be instructed on how to perform the exercises by
instructional videos and written protocols. The exercises (SMR or ECC) are to
be carried out 7 days a week for 12 weeks, twice a day.

In the SMR group, the participants will use a foam roller and a foam ball to
self-massage the plantar aponeurosis and the calf muscles twice a day for 90
seconds, respectively. In order to standardise the exerted pressure, a value of
6-7 for the on a numerical rating scale (NRS) ranging from 0 (no discomfort) to
10 (maximal discomfort) will be advised.

In the ECC group, the participants will perform an eccentric loading program
based on Alfredson et al. 1998. The participants will be instructed to allow
pain at the same amount as the SMR group during the sets.

The research will cost the participants time. They will come to the research
location two times, each appointment will last for approximately 15 minutes.
Furthermore, participants will follow a 12-week plan of exercises which will
take approximately 15 minutes per day. In addition to that the participants
will fill in an online questionnaire every week, which will in turn cost
maximum 15 minutes each time.
The only risk associated with participation will be that half of the
participants will not get one of the standard treatments (ECC) before the end
of the study. Furthermore, participants are expected to get muscle aches during
the first days of the trial and the exercises themselves can be painful. The
measurement of the mechanical pain threshold can also cause discomfort at that
moment. All these mentioned aches will last a short time and are of temporary
character, ultimately leading to a decrease of the pain and discomfort cause by
the achilles tendon complaints.