Inclusion Criteria:  To be healthy  Exclusion Criteria:  have suffered pain at an intensity of more than 2/10 for more than 8 days in the preceding year; having had a pain condition in the last 6 months for which treatment was sought; have undergone surgery in the neck or elbow region in the preceding year; suffer major depression or psychiatric illness (diagnosed by a psychiatrist and being in medical or psychiatric treatment); be diagnosed with life threatening, metabolic, cardiovascular, neurologic, systemic diseases; be pregnant or have given birth in the preceding year.