Inclusion Criteria:  subjects not using non-steroidal anti-inflammatory drugs (NSAIDs) for at least one week prior to study entry, age - 19-24 years, written consent to participate in the study.  Exclusion Criteria:  subjects studying for a degree in physiotherapy, subjects post surgery on the examined upper limb, subjects with past bone fractures in the examined upper limb, subjects who have had an injury to the examined upper limb within 6 months before the start of the study.