Isometric contraction – using PIR (in a chronic setting, with stretching, also known as post-facilitation stretching)


  • Stretching chronic or subacute restricted, fibrotic, contracted soft tissues (fascia, muscle) or tissues housing active myofascial trigger points.

Contraction starting point

Short of the resistance barrier.

Modus  Operandi

The affected muscles (the agonists) are used in the isometric contraction;   therefore the     shortened muscles subsequently relax via post-isometric contraction (PIR), allowing an easier stretch to be performed.  The operator is attempting to push towards the barrier of restriction against the patient’s precisely matched counter force.


Operator’s and patient’s forces are matched.  Initial effort involves approximately 30%of   patient’s strength; this can be increased on subsequent contractions to no more than 40%.

Duration of contraction

Initially 7-10 seconds.

CAUTION:  Longer, stronger contractions may predispose towards onset of cramping and so should be used with care.

Action following contraction

There should be a rest period of 5 seconds or so, to ensure complete relaxation before           commencing the stretch.  On exhalation, the area (muscle) is taken to its new restriction barrier, and a small degree beyond, painlessly, and held in this position for at least 30 and up to 60    seconds.  The patient should, if possible, participate in assisting in the move to, and through, the barrier, effectively inhibiting the structure being stretched and retarding the likelihood of a myotatic stretch reflex.


Repeat 3 times, or until no further gain in range of motion is possible, with each isometric  contraction commencing from a position just short of the restriction barrier.

Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s