Clinical observations have suggested a relationship between shoulder range of movement (ROM) and lateral epicondylalgia. This study reports the effect of a single intervention of a mobilization with movement (MWM) applied to the elbow, on shoulder rotation ROM in subjects with lateral epicondylalgia. Twenty-three subjects with lateral epicondylalgia were included. In a one-group pretest-post-test design, ROM of shoulder internal and external rotation were measured by goniometer before and after the application of the MWM, of both the unaffected and the affected limbs. Significant differences in pre-intervention external rotation ROM were found between unaffected and affected shoulders of subjects with lateral epicondylalgia, but no significant difference remained post-intervention. It may be concluded that restriction of shoulder rotation ROM is present in patients with lateral epicondylalgia, probably due to a facilitated level of shoulder rotator muscle tone. Shoulder internal and external rotation ROM increases significantly following MWM to the elbow, in subjects with unilateral lateral epicondylalgia. Surprisingly, these ROM increases are also apparent on the ‘unaffected’ limb. These findings suggest that the MWM causes a neurophysiologically mediated decrease in resting muscle tone.