Mechanical compression is applied with the thumb to the upper trapezius muscle on the non-dominant side at the midpoint between the acromion and C7. The intensity of this will be regulated by the pain it causes the patient, trying to ensure that it is at all times approximately 5/10 on the numerical pain rating scale (NPRS) with 0 being "no pain at all" and 10 being "the worst pain imaginable". The stimulation will be carried out for 2 minutes.

Mechanical compression is applied with the thumb to the upper trapezius muscle on the non-dominant side at the midpoint between the acromion and C7. The intensity of this will be regulated by the pain it causes the patient, trying to ensure that it is at all times approximately 2/10 on the numerical pain rating scale (NPRS) with 0 being "no pain at all" and 10 being "the worst pain imaginable". The stimulation will be performed for 2 minutes 4 times with 1 minute rest.

Mechanical compression is applied with the thumb. The intensity of this will be regulated by the pain it causes the patient, trying to ensure that it is at all times approximately 2/10 on the numerical pain rating scale (NPRS) with 0 being "no pain at all" and 10 being "the worst pain imaginable". Stimulation will be performed for 2 minutes, 4 times, at four different sites (left and right upper trapezius and left and right lumbar paravertebral) with 1 minute of rest.

Painful mechanical stimulus

PPTs will be assessed on the dominant side over the tibialis anterior muscle using a digital algometer (Wagner instruments, Greenwich, CT, USA). Participants will be instructed to say "stop" when the pressure sensation becomes painful. The average of 3 assessments on the tibialis anterior of the dominant side will be performed for analysis. The algometer pressure for assessment will be gradually increased at a rate of 1kg/second. Data will be collected in kg/cm2.