Effects of restrictive and non-restrictive harnesses on shoulder extension in dogs at walk and trot.

The study aimed to compare the effect of restrictive and non-restrictive harnesses on shoulder extension of dogs at walk and trot. This was a prospective study of nine dogs. Dogs were walked and trotted on a treadmill at a comfortable walking and trotting speed, first with no harness, then with each harness type, with and without added weights. Dogs were filmed and the angle of shoulder extension was measured using non-reflective markers and a video analysis software. Significant decrease in shoulder extension was found with both types of harnesses in comparison with no harness, except for the restrictive harness with weights. Shoulder extension was 2.6° and 4.4° less in dogs wearing a non-restrictive harness than in dogs wearing a restrictive harness, at walk and trot, respectively. The addition of weights did not consistently add more restriction to shoulder extension. The results of this study indicate that harnesses do limit shoulder extension, but perhaps not in the way originally anticipated, as results show extension is significantly reduced under the non-restrictive harnesses compared with the restrictive harnesses, with and without weights.