Have you ever experienced plantar fasciitis or achilles tendinopathy? Chances are that either
you or someone you know has – given its prevalence in general populations. If so, you are
probably familiar with the amount of time it takes to completely heal from this diagnosis and
know that it can stay with you, on and off, for months to years. You have probably had
physiotherapy, performed stretches and strengthening exercises, changed your shoes, or even
had custom orthotics made to try to help.
It is well recognized that stretching is the single, most effective conservative treatment for these
indications. And there is an enormous amount of information and advice available when trying to
determine what is the best stretching regimen for yourself. Questions may include: what to
stretch, how to stretch, how long to hold a stretch, how hard to stretch, and how often to stretch!
As a physiotherapist, the importance of being specific to exactly what needs to be stretched
indicates the answers to these questions because there are many different techniques and
approaches when stretching different kinds of tissues in your body.
Stretches can be applied to muscle or contractile tissue, as well as to fascia, tendons and connective tissue or non-contractile tissue. Knowing what tissue type you are targeting makes a difference in how to stretch.
In the case of plantar fasciitis or achilles tendinopathy, there are often changes that have
occurred to the fascia, tendons, and other tissues. These changes have typically occurred over
a long period of time, even though symptoms may feel like they arose overnight! Besides the
typical calf stretches and arch rolling exercises that are often prescribed for rehabilitation of an
injury to the plantar fascia or achilles tendon, which target the muscles of the calf and the sole of
the foot, getting a low load prolonged stretch to the connective tissue of the foot and ankle can
be highly effective. There are many reasons why.
Firstly, connective tissue – fascia, tendon, capsule, ligament, interstitial tissues – are made of
collagen and elastin. These tissues differ dramatically from muscle. At rest, connective tissue is
wavy and looks like it is “crimped”. When applying stretch to this tissue, the creep must be taken
up first – in other words: the crimped/wavy nature of the tissue must be straightened – before a
stretch can be applied to lengthen it. Then, one needs to continue to stretch the tissue for a long
duration. Numerous studies with people who have contractures (shortened connective tissue)
around various joints, have shown that stretching must be of a prolonged and low load intensity
in order to make an impact to the length of the tissue, and is shown to be more successful than
a high intensity, brief duration stretch. This allows for the appropriate deformation of the
connective tissue around the joint and for the muscle or contractile tissue to adapt to the stretch
without pain or resistance to the stretch.
One way to achieve this low load prolonged stretch is by using a brace or splint. The use of a
splint, especially while sleeping, can be extremely helpful and time effective. Night splints are an
excellent way to achieve this low load, long duration stretching, targeting the non-contractile
connective tissue of the foot and ankle, and letting the muscle softly accommodate to the stretch
while you are at rest for long periods of time. Lengthening non-contractile tissue takes time. Use
of a night splint in combination with more traditional muscle stretching and strengthening
protocols can really help speed recovery of plantar fasciitis or achilles tendinopathy.