Canine Muscles and Movement

Different muscles play different roles in posture and movement, and effectively assessing their function can only be achieved with the help of professionals such as vets and therapists. Therefore, work with a professional to get effective therapeutic and performance enhancing aims for your dog…BUT understanding more about these muscles and their roles, will help you work them correctly through therapeutic exercises/warm ups to prevent injury in the first place!

Figure 1. Canine superficial muscles (Canine Anatomy 3D App)

Forward motion is initiated by the combined actions of the legs balanced with the efforts of the core muscles in the abdomen, thorax and even neck. A biped (human) has two step cycles in motion (2 legs), a quadruped (dog) has four step cycles. One step cycle for a limb would be when the paw first hits the ground, all the way through until it is lifted and re-hits the ground at the next point (Gillette, 2019).

To get this correct motion the muscles need to work in different roles, in different parts of the stride. In figure 2 you can see how the hindlimbs stabilise during early-mid stance, and propulsion is generated when the hindlimbs are in late stance to pull them forwards, with the forelimbs assisting with propulsion during the late stance to early swing phase, and braking motion in early stance to control the power (Tokuri et al. 1973a). (Click on images to zoom in).

Figure 2. muscle activity during different parts of the stride. (Green = propulsive, Amber = stabilisation, Red = braking) Forelimb top image, hindlimb bottom image)

Some muscles are considered primary movers which have related antagonistic muscles that work against them to maintain control of power, as well as synergistic muscles that assist in the primary movers actions; and finally there are stabilising muscles that act to hold bones in place for postural purposes (Gillette, 2019)  All of these are continually acting in an intentional or reactionary manner as we move or stand.

In the forelimbs, movement rotate around the upper edge of the shoulder blade (scapula) and the hindlimbs rotate around the hip joint, with the back (particularly lumbar) playing a large role in all gaits for stabilisation (particularly in gallop) (Fischer and Lilje, 2020). The most important muscles in speed and stride length are the muscles that connect the shoulder to the trunk, muscles along the topline, and muscles involved in hindlimb retraction (Fischer and Lilje, 2020).

During walk, the muscles of the shoulder “girdle” and joint (e.g. trapezius, rhomboideus, supraspinatus, infraspinatus, etc) are active as postural stabiliser muscles, with the biceps brachii and deltoideus most active in the late stance phase ready for forward motion, with the brachiocephalicus having initiated movement (Fischer and Lilje, 2020). Muscles such as the extensor carpi radialis and triceps brachii active in early stance to decelerate the limb and stabilise (Tokuri, 1973a; Fischer and Lilje, 2020). With the the illopsoas, gracilis and sartorius becoming active mid swing for ground clearance and the gluteus medius, biceps femoris, quadriceps, and gastrocnmius all becoming active late swing to stabilise every joint for landing, and the hamstring muscles (semitendinosus, biceps femoris) creating power in the late stance-swing phase (Tokuri, 1973a).

Trot shows similar muscular patterns, but due to its greater speed and spring mechanism through the limbs, there is greater force through the forelimbs and needing greater stabilisation such as from the trapezius (Carrier et al. 2008), and with spinal stabilisation occurring to transfer forces from the hindlimb forwards through lateral motion (Tokuri, 1973b; Fischer and Lilje, 2020), meaning dogs with forelimb issues or back pain, will become more apparent during trotting motion.

Gallop is an asymmetric gait, with leading and trailing limbs, meaning a dog can offload a specific leg by spending its time “running” as opposed to walking. The trailing forelimb and neck takes more weight during stance, with the muscles of the shoulder girdle and neck becoming active in the leading forelimb during mid-late swing to assist with deceleration (Tokuri, 1974). Additionally, as the hindlimbs are in the air during swing phase, the centre of gravity is shifted forwards to the forelimbs. The axial skeleton/spine is undergoes huge range of motion in gallop, with paraspinal muscles active between T4-9 during forelimb stance for stabilisation (Tokuri, 1974). In the hindlimbs the gluteus medius, semitendinosus and semimembranosus become active at landing AND take off for stabilisation and propulsion, meaning these muscles are more active in gallop than walk and trot, with trailing hindlimb muscles more active during stance than the leading due to the centre of gravity coming backwards to allow swing of the forelimbs (Tokuri, 1974; Goslow et al. 1981). Additionally medial adductor muscles such as gracilis are more active on landing as speed increases for stabilisation, and muscles such as the tibialis cranialis/anterior show greater activity in gallop in the late stance to assist with propulsion by flexing the hock (Tokuri, 1974; Fischer and Lilje, 2020). Additionally inclines (10% or more) can create more power, activating the hindlimb retractors such as the hamstrings (biceps femoris, semitendinosus and semimembranosus) by 20x (Fischer and Lilje, 2020).

Many conditions interfere with this motion, such as hip dysplasia impacting all gaits due to the instability of the hip joint for motion, particularly noticeable in gallop due to the desire to “bunny hop” to spread the force across both hindlimbs instead of just the trailing hindlimb, and with a reduction in power production in the muscles surrounding the hip such as biceps femoris and gluteus medius (Bockstahler et al. 2012), meaning their hindlimb muscles will atrophy (reduce). Cruciate ligament disease causes issues with stifle stabilisation (Adrian et al. 2013), and therefore obvious changes even in walking gait with offloading of the injured leg. Back pain causing the dog to become slower to prevent high range of motion forces as noted in gallop. And elbow dysplasia can cause significant lameness in trot and gallop due to the additional forces, as well as pain and spasms of the biceps brachii and brachialis muscles which can impinge the elbow and produce power of the forelimb, with atrophy of the supraspinatus and/or infraspinatus common in shoulder injuries due to their role in shoulder stabilisation in movement (Fitch, n.d.).

Figure 3. Example of atrophy (left hindlimb) and change in weightbearing due to injury

This is where physiotherapy and targeted exercises like sit to stands, pole work, etc can assist with correct movement and/or easing discomfort by lifting weight off an injured forelimb, assisting with correct plane of movement, creating muscle mass from low impact activities. However, it is important to take it slowly, it takes weeks to build muscle strength, and many activities can be progressed through the weeks to push the body to adapt further for other tasks such as agility. Therefore, if your dog is not moving correctly, or seems in discomfort, work with a physiotherapist to see if there are barriers to them moving effectively and causing pain.

Any questions feel free to get in touch, as this has been a very whistle stop tour…next stop…agility manoeuvres like jumping, weaves, etc.


Adrian, C. P., Haussler, K. K., Kawcak, C. E., et. al.(2019). Gait and electromyographic alterations due to early onset of injury and eventual rupture of the cranial cruciate ligament in dogs: A pilot study. Veterinary Surgery, 48(3), 388-400

Bockstahler, B., Kräutler, C., Holler, P., et. al. (2012). Pelvic limb kinematics and surface electromyography of the vastus lateralis, biceps femoris, and gluteus medius muscle in dogs with hip osteoarthritis. Veterinary Surgery, 41(1), 54-62

Carrier, D.R., Deban, S.M., Fischbein, T., (2008). Locomotor function of forelimb protractor and retractor muscles of dogs: evidence of strut-like behaviour in the shoulder. Journal of Experimental Biology, 211(1), 150-160

Fischer, M.S., and Lilje, K.E., (2020). Muscles. Dogs in Motion. VDH. 2nd edition: 124-128

Fitch, R.B., n.d. Diagnostic tips for forelimb lameness in dogs. VetFolio [online]. Available: THE UNDERSYNOVIAL WORLD OF ARTHROSCOPY: MAXIMIZING YOUR EFFORTS THROUGH MINIMAL APPROACHES (

Gillette, R., (2019). Muscle Actions of the Legs During Locomotion of the Dog. [online]. Available: Muscle Actions of the Legs During Locomotion of the Dog –

Goslow, G. E., Seeherman, H. J., Taylor, C. R., et. al. (1981). Electrical activity and relative length changes of dog limb muscles as a function of speed and gait. Journal of Experimental Biology, 94(1), 15-42

Tokuriki, M. (1973)a. Electromyographic and joint-mechanical studies in quadrupedal locomotion. I. Walk. Nihon juigaku zasshi. The Japanese journal of veterinary science35(5), 433-436

Tokuriki, M. (1973)b. Electromyographic and joint-mechanical studies in quadrupedal locomotion. II. Trot. Nihon juigaku zasshi. The Japanese journal of veterinary science35(6), 525-533

Tokuriki, M. (1974). Electromyographic and joint-mechanical studies in quadrupedal locomotion. III. Gallop. Nihon juigaku zasshi. The Japanese journal of veterinary science36(2), 121-132