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Motions of the running horse and cheetah revisited: Fundamental mechanics of the transverse and rotary gallop

Department of Cell Biology and Anatomy, Faculty of Medicine, University of Calgary, Calgary, Alta, Canada T2N 4N1.
Journal of The Royal Society Interface (Impact Factor: 3.86). 11/2008; 6(35):549-59. DOI: 10.1098/rsif.2008.0328
Source: PubMed

ABSTRACT Mammals use two distinct gallops referred to as the transverse (where landing and take-off are contralateral) and rotary (where landing and take-off are ipsilateral). These two gallops are used by a variety of mammals, but the transverse gallop is epitomized by the horse and the rotary gallop by the cheetah. In this paper, we argue that the fundamental difference between these gaits is determined by which set of limbs, fore or hind, initiates the transition of the centre of mass from a downward-forward to upward-forward trajectory that occurs between the main ballistic (non-contact) portions of the stride when the animal makes contact with the ground. The impulse-mediated directional transition is a key feature of locomotion on limbs and is one of the major sources of momentum and kinetic energy loss, and a main reason why active work must be added to maintain speed in locomotion. Our analysis shows that the equine gallop transition is initiated by a hindlimb contact and occurs in a manner in some ways analogous to the skipping of a stone on a water surface. By contrast, the cheetah gallop transition is initiated by a forelimb contact, and the mechanics appear to have much in common with the human bipedal run. Many mammals use both types of gallop, and the transition strategies that we describe form points on a continuum linked even to functionally symmetrical running gaits such as the tölt and amble.

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    • "have argued that the fundamental reason CoM work and power are needed in steady, terrestrial locomotion is to replace the kinetic energy losses that occur when the CoM and limbs collide with the ground (e.g., Ruina et al., 2005; Bertram and Gutmann, 2009; Lee et al., 2011). Further, recent studies have shown the CoM work and power measured per stride are directly proportional to the geometry of these collisions (Lee et al., 2011; O'Neill and Schmitt, 2012). "
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    ABSTRACT: Tufted capuchin monkeys are known to use both quadrupedalism and bipedalism in their natural environments. Although previous studies have investigated limb kinematics and metabolic costs, their ground reaction forces (GRFs) and center of mass (CoM) mechanics during two and four-legged locomotion are unknown. Here, we determine the hind limb GRFs and CoM energy, work, and power during bipedalism and quadrupedalism over a range of speeds and gaits to investigate the effect of differential limb number on locomotor performance. Our results indicate that capuchin monkeys use a "grounded run" during bipedalism (0.83-1.43 ms(-1) ) and primarily ambling and galloping gaits during quadrupedalism (0.91-6.0 ms(-1) ). CoM energy recoveries are quite low during bipedalism (2-17%), and in general higher during quadrupedalism (4-72%). Consistent with this, hind limb vertical GRFs as well as CoM work, power, and collisional losses are higher in bipedalism than quadrupedalism. The positive CoM work is 2.04 ± 0.40 Jkg(-1) m(-1) (bipedalism) and 0.70 ± 0.29 Jkg(-1) m(-1) (quadrupedalism), which is within the range of published values for two and four-legged terrestrial animals. The results of this study confirm that facultative bipedalism in capuchins and other nonhuman primates need not be restricted to a pendulum-like walking gait, but rather can include running, albeit without an aerial phase. Based on these results and similar studies of other facultative bipeds, we suggest that important transitions in the evolution of hominin locomotor performance were the emergences of an obligate, pendulum-like walking gait and a bouncy running gait that included a whole-body aerial phase. Am J Phys Anthropol, 2012. © 2012 Wiley Periodicals, Inc.
    American Journal of Physical Anthropology 01/2013; 150(1). DOI:10.1002/ajpa.22176 · 2.51 Impact Factor
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    • "–1 during galloping. All dogs displayed a lateral sequence walk, a trot with synchronized diagonal limb movements (Hildebrand, 1966) and a transverse gallop (Hildebrand, 1977) with a forelimb-initiated aerial phase (Bertram and Gutmann, 2009). EMG signals were recorded from eight dogs walking, 12 dogs trotting and nine dogs galloping with the ipsilateral limb acting as either the trailing limb (i.e. the first limb to touch down) or the leading limb (i.e. the second limb to touch down). "
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    ABSTRACT: The extrinsic limb muscles perform locomotor work and must adapt their activity to changes in gait and locomotor speed, which can alter the work performed by, and forces transmitted across, the proximal fulcra of the limbs where these muscles operate. We recorded electromyographic activity of 23 extrinsic forelimb and hindlimb muscles and one trunk muscle in dogs while they walked, trotted and galloped on a level treadmill. Muscle activity indicates that the basic functions of the extrinsic limb muscles - protraction, retraction and trunk support - are conserved among gaits. The forelimb retains its strut-like behavior in all gaits, as indicated by both the relative inactivity of the retractor muscles (e.g. the pectoralis profundus and the latissimus dorsi) during stance and the protractor muscles (e.g. the pectoralis superficialis and the omotransversarius) in the first half of stance. The hindlimb functions as a propulsive lever in all gaits, as revealed by the similar timing of activity of retractors (e.g. the biceps femoris and the gluteus medius) during stance. Excitation increased in many hindlimb muscles in the order walk-trot-gallop, consistent with greater propulsive impulses in faster gaits. Many forelimb muscles, in contrast, showed the greatest excitation at trot, in accord with a shorter limb oscillation period, greater locomotor work performed by the forelimb and presumably greater absorption of collisional energy.
    Journal of Experimental Biology 01/2012; 215(Pt 2):287-300. DOI:10.1242/jeb.063230 · 3.00 Impact Factor
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    • "If the animal runs on a narrow branch, the transfer of energy could cause the branch to oscillate, which could destabilize the running animal. Bertram and Gutmann (2008) suggest that a gallop, with its four separate footfalls, can reduce the amount of energy imparted to the ground or branch. We therefore predict that when an arboreal animal's mass relative to branch diameter is substantial enough to cause a branch to oscillate and destabilize the animal, that animal will run with a gallop or halfbound instead of a bounding gait. "
    Theoretical Biomechanics, 11/2011; , ISBN: 978-953-307-851-9
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