The control group will receive a best clinical practice home-exercise program, with regular follow-ups at the shoulder clinic every other week. The details are described in Granviken et al. (2015).

Weight (kg)

Height (cm)

Age (years)

Duration of symptoms (months)

What shoulder is affected (left/right)

The patient fills in a questionnaire stating number of children, marital status, welfare status and working situation

After warmup: maximal strength was measured as the weight the subject could manage to lift once - usually achieved in 3-5 attempts. The movement conducted was the earlier described scapularization movement.

After warmup: maximal strength was measured as the weight the subject could manage to lift once - usually achieved in 3-5 attempts. The movement conducted was the earlier described scapularization movement.

Subject abduct their shoulder up to 90 degrees in scapula's plane (scapularization) at a frequency of 0,5 Hz. The load is set to 80% of the incremental time to exhaustion test. The test is stopped if the fails to maintain pace or movement quality, or the subject experience increased pain. Time at failure is noted as the result.

Subject abduct their shoulder up to 90 degrees in scapula's plane (scapularization) at a frequency of 0,5 Hz. The load is set to 80% of the incremental time to exhaustion test. The test is stopped if the fails to maintain pace or movement quality, or the subject experience increased pain. Time at failure is noted as the result.

Baseline images will be taken with ultrasonic device to confirm an intact m. supraspinatus. An intravenous line will be inserted in the contralateral arm and the patient will be injected with a bolus of contrast dye (Optison, 3 ml bolus, 0.19 mg / mL perflutren). The injection is administered by a physician related to the research project. Measurements of regional blood flow at rest made are of the supraspinatus tendon. Then the participants perform a standardized training exercise to recruit the vasculature in m. supraspinatus (scapularization to 90 degrees, 80% of TTU weight (incremental), 3 minutes). Post-exercise images are taken immediately after this.

Baseline images will be taken with ultrasonic device to confirm an intact m. supraspinatus. An intravenous line will be inserted in the contralateral arm and the patient will be injected with a bolus of contrast dye (Optison, 3 ml bolus, 0.19 mg / mL perflutren). The injection is administered by a physician related to the research project. Measurements of regional blood flow at rest made are of the supraspinatus tendon. Then the participants perform a standardized training exercise to recruit the vasculature in m. supraspinatus (scapularization to 90 degrees, 80% of TTU weight (incremental), 3 minutes). Post-exercise images are taken immediately after this.