In 2012, I was a keynote speaker at the Canine & Feline Behaviour Association Conference, presenting how our training equipment affects biomechanics and in turn behaviour. At the time, research on harnesses was sparse, but even in 2012 my conclusion was clear - the harness appears to negatively impact the way a dog moves.

As a dog behaviourist with a background in kinesiology, canine anatomy and the mechanics of movement, I’ve subsequently spent many years since that conference, researching the impact of equipment on our dogs.

My Master’s degree in Canine Behaviour and Psychology in 2011 was based on Canine Cognition but it really unleashed an appreciation of robust research as well as anecdotal evidence and, as the popularity of the harness increased, so too did my need of wanting to research the impact of it.

As such I returned to academia to study the effect of dog walking equipment on canine form and function at the University of the West of Scotland (UWS) for almost two years (2020 - 2021), critically analysing how different equipment influences how our dogs move.

Dogs are sentient beings—some react more to touch and proprioceptive stimuli, causing them to pull away from equipment, while many will lean into pressure, which is known as the opposition reflex, and that's even before a lead attached.

With an increasing number of scientific studies on harnesses, we now have more data to support the concerns I’ve had over this piece of equipment. As the harness is exponentially increasing in popularity and has started to be marketed as a 'must have' fashion accessory for your dog, it is more important than ever that we realise that there is a negative impact on our dogs' well-being.

Science is catching up.

Over the last decade, multiple studies have examined the biomechanics of harness use. The studies confirm that all dog walking harnesses impact movement, but the extent depends on design, fit, and the individual dog.

One of my primary concerns while researching at UWS was the methods being used in studies for testing canine movement as some of them used treadmills, which I believe may have given false readings due to not all dogs being comfortable moving at a set mechanical pace.

Also the number of dogs included in the studies as well as the range of equipment used was low, which really made the results, while interesting, statistically insignificant…

Ideally, any study should have tracked joint rotation and lateral swing by filming dogs from all angles, including from above, while walking naturally over a pressure-sensitive walkway.

Here follows overviews of some studies (in date order) relating to the dog walking harness – I have deliberately omitted the research carried out on service dogs, for example Peham et al. (2013) who looked at the effect of pressure distribution of guide dog harnesses and Gates et al. (2023) comparing guide dog harnesses, as my focus has been for pet owners.

Note: The Y shaped harness is classed as non-restrictive, whereas the straight front harness is classed as restrictive.

Carr et al. (2017) – Harnesses for Agility Dogs

This study investigated how different harness types affect movement in agility dogs and highlighted (although I hasten to add they weren’t doing agility at the time) that improper harness design can interfere with natural movement, reinforcing the importance of selecting the right fit and style, particularly for high-performance and working dogs.

The key findings from the study were

• Harnesses with straps crossing the shoulders may restrict forelimb movement and impact stride length.
• Harnesses that that had the most surface area touching the dog’s body had the greatest impact.
• Y-front and well-fitted designs allowed for more natural movement whereas the step-in and chest-plate designs showed varying degrees of restriction.

Lafuente et al. (2018) - Effects of restrictive and non-restrictive harnesses on shoulder extension in dogs at walk and trot

This study assessed, via video analysis, the impact of restrictive vs. non-restrictive harnesses on shoulder extension in dogs by observing nine dogs walking and trotting on a treadmill while wearing different harnesses.

This was the first study to highlight that the non-restrictive harness is actually more restrictive than the restrictive harness in relation to shoulder extension.

The key findings from the study were

• The non-restrictive Y-front harnesses reduced shoulder extension by 5° at a walk and 10° at a trot, while restrictive chest-strap harnesses reduced shoulder extension by an average of 2° at a walk and 5° at a trot.
• Adding weights did not consistently result in further restriction of shoulder extension.

Kiss et al. (2018) –Biomechanical analysis of the kinematics of different dog harnesses

Using five dogs of different breeds, this study examined, using 3D motion capture, whether three different harnesses affected canine gait and movement while walking on both the floor and the treadmill.

The key findings from the study were that harnesses did not significantly alter movement patterns compared to walking without a harness.

Blake et al. (2019) - Biomechanical Effects of Harness and Head-Collar Use in Dogs'

This study reviewed the three existing pieces of research on the biomechanical effects of harnesses and head-collars (Halti) on canine gait and movement; both of Peham’s research on guide dogs harnesses plus the Lafuente study.

As noted under the Lafuente study above, the Y shaped non-restrictive harness was actually the more restrictive design.

Pálya et al. (2022) – Development of a detailed canine gait analysis method for evaluating harnesses

This pilot study was to establish a method for analysing gait changes due to harness use via motion capture technology measuring 18 joint angles and 35 movement parameters.

Although the study was only carried out on four dogs, making the results statistically insignificant, it did highlight that two thirds of the harnessed dogs showed significant gait changes and recommended more research to assess the effects on puppy development.

Williams et al. (2023) – Effect of Harness Design on the Biomechanics of Domestic Dogs (Canis lupus familiaris)

This study was looking to establish the impact of three popular commercially available harnesses on stride length, weight distribution, and shoulder joint angles. Sixty-six dogs were analysed using a Tekscan Strideway gait analysis system to measure movement changes in various harnesses.

Key Findings:

• Significant differences were observed in stride length and in weight distribution across the different harnesses tested.
• While variations in shoulder joint angles were noted, they were not statistically significant, however, there were clear differences in how much the elbow joint moved in the different harnesses.
• Harnesses influenced stride and gait, indicating that the biomechanics of movement were impeded depending on the design.
• The effects of harness design on gait varied among different breeds and breed types, indicating that individual anatomical differences play a role in how harnesses impact movement.

Dowdeswell & Churchill (2024) – The Influence of Harness Design on Forelimb Biomechanics in Pet Dogs

This is the latest and most up to date study on the dog walking harness, which not only reviews the literature and studies that came before it but also did an extensive study with 30 dogs using six common harness designs, all of which were assessed using high-speed video analysis.

The aim was to explore the impact of the six different harness types on canine biomechanics compared to a standard collar, specifically analysing shoulder extension, shoulder flexion, elbow extension, and elbow flexion.

Key Findings:

• The front-clip harnesses resulted in the least elbow and shoulder flexion and extension, indicating a significant reduction in these movements.
• The straight-front harnesses (like Julius K9) allowed for the most elbow and shoulder extension and flexion among all harnesses tested.
• The Y-front harness is commonly sold as ‘non-restrictive’, but this study has proven that it restricts flexion and extension of both the elbow and shoulder, which is a misrepresentation to the buyers.
• Alternatively, the Julius K9 straight-front harness, often labelled as ‘restrictive’ and is regularly disfavoured by animal professionals and the public, has been proven to have little impact on canine biomechanics.

Final Thoughts

Let’s make no bones about it, the dog walking harness industry is big bucks… from the ‘cutesy’ harnesses on Amazon for £5.99, to NEXT selling ‘boutique’ harnesses, to businesses promoting ‘couture’ harness clubs.

My biggest concern is that these cute material harnesses that are being sold for puppies and are causing untold damage to the shoulder action, thereby setting the dog (and the owner) up for pain in future years - this needs to change.

Future research should explore the long-term effects of dogs wearing a harness, both moving freely and being walked normally by the owner (whether that includes pulling or not).

Most importantly though, I believe that future research also needs to be done in the real world and that means putting harnesses on as the owners would, rather than having perfectly fitting harnesses, which, in the real world are far and few between.

The analysed walk also needs to be a normal walk involving left and right turns, sitting, stopping and walking at the owner’s normal pace… including the odd head down for a sniff.

Hopefully with this new body of evidence things will start to change, and I recommend, that if you read only one piece of research in full, you read the 2024 study by Dowdeswell and Churchill, as not only have the researchers done their own testing on thirty dogs with six harnesses, but they’ve completed a thorough literature review of existing research.

The diagrams and graphs that they’ve produced are easy to decipher and indicate quite clearly the impact on the shoulder girdle and stride length by the different harnesses tested, and, to give you a flavour and to encourage you to read the research (which thankfully has less ‘academic speak’ than most), here are two of the diagrams depicting the relative impact to the elbow and shoulder extension.

Figure 1: Box-and-whisker plot showing elbow extension for each harness design
(Dowdeswell and Churchill, 2024, p. 7).

Figure 3: Box-and-whisker plot showing shoulder extension for each harness design
(Dowdeswell and Churchill, 2024, p. 9).

And as surprising as it may be, the Julius K9 straight front harness came out as the least impactful…

The research on harnesses is evolving, but needs to include so much more than it has to date, however one thing is clear and shines out like a beacon: -

Harnesses change how dogs move and have a significant negative impact on
our dog’s action and gait… even when there is no lead tension.

References in date order

Carr, B.J., DVM, CCRT, Zink, C., DVM, PhD, DACVSMR, DACVP, et al. (2017) 'Harnesses for Agility Dogs'. Clean Run Magazine.

Kiss, R., Farkas, G., Meszlényi, R., et al. (2018) 'Biomechanical analysis of the kinematics of different dog harnesses', Julius-K9 Research Division Report.

Lafuente, M.P., Provis, L., and Schmalz, E.A. (2018) 'Effects of restrictive and non-restrictive harnesses on shoulder extension in dogs at walk and trot'. Veterinary Record, 184(2), p. 64.

Blake, S., Williams, R., and Ferro de Godoy, R. (2019) 'A Systematic Review of the Biomechanical Effects of Harness and Head-Collar Use in Dogs', bioRxiv.

Graham, L (2021) The Impact of Dog Walking Equipment on Canine Form and Function. Unpublished research.

Pálya, B., Nagy, A., Miklósi, Á., and Kiss, R.M. (2022) 'Development of a detailed canine gait analysis method for evaluating harnesses: A pilot study'. PLOS ONE, 17(3), e0264299.

Williams, J.L., Anderson, K.L., and Stafford, K.J. (2023) 'Effect of harness design on the biomechanics of domestic dogs (Canis lupus familiaris)'. PeerJ, 11, e16278.

Dowdeswell, L. and Churchill, L. (2024) 'The Influence of Harness Design on Forelimb Biomechanics in Pet Dogs'. Reinvention: an International Journal of Undergraduate Research, 17(S1).