Forty patients with unilateral lateral elbow tendinopathy were randomized to receive 8 weeks of an isometric exercise program or a wait-and-see approach. The primary outcomes of interest were the Patient Rated Tennis Elbow Evaluation (PRTEE) and associated sub-scores, global rating of change and pain-free grip strength in the affected arm. Secondary outcomes of interest included pain at rest and worst pain on a numeric rating scale, as well as cold, heat and pressure pain thresholds. Results revealed significantly favourable PRTEE pain, usual activity, specific activity and total scores in the isometric exercise group compared to the control group. Worst pain scores on the numeric rating scale were significantly in favour of the isometric exercise group. Otherwise, no significant differences were observed between the two groups.