Terrestrial locomotion has evolved as animals adapted from aquatic to terrestrial environments. Locomotion on land raises different problems than that in water, with reduced friction being replaced by the increased effects of gravity .
135-448: Running is a method of terrestrial locomotion by which humans and other animals move rapidly on foot. Running is a gait with an aerial phase in which all feet are above the ground (though there are exceptions). This is in contrast to walking , where one foot is always in contact with the ground, the legs are kept mostly straight, and the center of gravity vaults over the stance leg or legs in an inverted pendulum fashion. A feature of
270-507: A hip replacement operation due to fractures or illnesses such as osteoarthritis . Hip pain can have multiple sources and can also be associated with lower back pain . At the 2022 Consumer Electronics Show , a company named Safeware announced an airbag belt that is designed to prevent hip fractures among such uses as the elderly and hospital patients. Abnormal orientation of the acetabular socket as seen in hip dysplasia can lead to hip subluxation (partial dislocation), degeneration of
405-455: A mud slick known as a "beaver slide" over a short distance when passing from land into a lake or pond. Human locomotion in mud is improved through the use of cleats . Some snakes use an unusual method of movement known as sidewinding on sand or loose soil. Animals caught in terrestrial mudflows are subject to involuntary locomotion; this may be beneficial to the distribution of species with limited locomotive range under their own power. There
540-407: A buttonhole on the femoral head and assists in maintaining the contact in the joint. All three ligaments become taut when the joint is extended - this stabilises the joint, and reduces the energy demand of muscles when standing. The intracapsular ligament, the ligamentum teres , is attached to a depression in the acetabulum (the acetabular notch) and a depression on the femoral head (the fovea of
675-473: A component of their locomotion repertoire, such as the dung beetle when rolling a ball of dung, which combines both rolling and limb-based elements. The remainder of this article focuses on the anatomical and physiological distinctions involving terrestrial locomotion from the taxonomic perspective. Movement on appendages is the most common form of terrestrial locomotion, it is the basic form of locomotion of two major groups with many terrestrial members,
810-576: A fair number – woodlice having fourteen legs. Also, as previously mentioned, some insect larvae such as caterpillars and sawfly larvae have up to five (caterpillars) or nine (sawflies) additional fleshy prolegs in addition to the six legs normal for insects. Some species of invertebrate have even more legs, the unusual velvet worm having stubby legs under the length of its body, with around several dozen pairs of legs. Centipedes have one pair of legs per body segment, with typically around 50 legs, but some species have over 200. The terrestrial animals with
945-402: A few wild African ungulates, to even-toed ungulates, such as pigs, cows, deer, and goats. Mammals whose limbs have adapted to grab objects have what are called prehensile limbs. This term can be attributed to front limbs as well as tails for animals such as monkeys and some rodents. All animals that have prehensile front limbs are plantigrade, even if their ankle joint looks extended (squirrels are
1080-449: A fully erect posture, though each evolved it independently. In these groups the legs are placed beneath the body. This is often linked with the evolution of endothermy , as it avoids Carrier's constraint and thus allows prolonged periods of activity. The fully erect stance is not necessarily the "most-evolved" stance; evidence suggests that crocodilians evolved a semi-erect stance in their forelimbs from ancestors with fully erect stance as
1215-464: A good example). Among terrestrial invertebrates there are a number of leg forms. The arthropod legs are jointed and supported by hard external armor, with the muscles attached to the internal surface of this exoskeleton . The other group of legged terrestrial invertebrates, the velvet worms , have soft stumpy legs supported by a hydrostatic skeleton . The prolegs that some caterpillars have in addition to their six more-standard arthropod legs have
1350-655: A key part of the ancient Olympic Games as well as the modern Olympics. The activity of running went through a period of widespread popularity in the United States during the running boom of the 1970s . Over the next two decades, as many as 25 million Americans were doing some form of running or jogging – accounting for roughly one tenth of the population. Today, road racing is a popular sport among non-professional athletes, who included over 7.7 million people in America alone in 2002. Footspeed , or sprint speed,
1485-465: A lateral wave travels down the snake's body in the opposite direction to the snake's motion and pushes the snake off irregularities in the ground. This mode of locomotion requires these irregularities to function. Another form of locomotion, rectilinear locomotion , is used at times by some snakes, especially large ones such as pythons and boa . Here large scales on the underside of the body, known as scutes are used to push backwards and downwards. This
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#17327732256981620-462: A layer of mucus that is secreted from their underside, reducing friction and protecting from injury when moving over sharp objects. Earthworms have small bristles ( setae ) that hook into the substrate and help them move. Some animals, such as leeches , have suction cups on either end of the body allowing two anchor movement . Some limbless animals, such as leeches, have suction cups on either end of their body, which allow them to move by anchoring
1755-414: A line passing from the anterior to the posterior acetabular rim and the sagittal plane. It measures 7° at birth and increases to 17° in adults. Wiberg's centre-edge angle (CE angle) is an angle between a vertical line and a line from the centre of the femoral head to the most lateral part of the acetabulum, as seen on an anteroposterior radiograph . The vertical-centre-anterior margin angle (VCA)
1890-453: A measured course over an established road (as opposed to track and cross country running ). These events normally range from distances of 5 kilometers to longer distances such as half marathons and marathons , and they may involve scores of runners or wheelchair entrants. Cross country running takes place over the open or rough terrain. The courses used for these events may include grass , mud , woodlands, hills, flat ground and water. It
2025-437: A mid/forefoot strike may aid in propulsion. However, even among elite athletes, there are variations in self-selected footstrike types. This is especially true in longer distance events, where there is a prevalence of heel strikers. There does tend however to be a greater percentage of mid/forefoot striking runners in the elite fields, particularly in the faster racers and the winning individuals or groups. While one could attribute
2160-532: A protective armoured ball. Moroccan flic-flac spiders , if provoked or threatened, can escape by doubling their normal walking speed using forward or backward flips similar to acrobatic flic-flac movements. The fastest terrestrial animal is the cheetah , which can attain maximal sprint speeds of approximately 104 km/h (64 mph). The fastest running lizard is the black iguana , which has been recorded moving at speed of up to 34.9 km/h (21.7 mph). Hip joint In vertebrate anatomy ,
2295-447: A result of adapting to a mostly aquatic lifestyle, though their hindlimbs are still held fully erect. For example, the mesozoic prehistoric crocodilian Erpetosuchus is believed to have had a fully erect stance and been terrestrial. The number of locomotory appendages varies much between animals, and sometimes the same animal may use different numbers of its legs in different circumstances. The best contender for unipedal movement
2430-416: A running body from the viewpoint of spring-mass mechanics is that changes in kinetic and potential energy within a stride co-occur, with energy storage accomplished by springy tendons and passive muscle elasticity. The term "running" can refer to a variety of speeds ranging from jogging to sprinting . Running in humans is associated with improved health and life expectancy . It is hypothesized that
2565-517: A similar form to those of velvet worms, and suggest a distant shared ancestry. Animals show a vast range of gaits , the order that they place and lift their appendages in locomotion. Gaits can be grouped into categories according to their patterns of support sequence. For quadrupeds , there are three main categories: walking gaits, running gaits, and leaping gaits . In one system (relating to horses), there are 60 discrete patterns: 37 walking gaits, 14 running gaits, and 9 leaping gaits . Walking
2700-446: A slow increase in speed and distance. While running, it is best to pay attention to how one's body feels. If a runner is gasping for breath or feels exhausted while running, it may be beneficial to slow down or try a shorter distance for a few weeks. If a runner feels that the pace or distance is no longer challenging, then the runner may want to speed up or run farther. Running can also have psychological benefits, as many participants in
2835-417: A small vessel in the ligament of the head of the femur which is a branch of the posterior division of the obturator artery , which becomes important to avoid avascular necrosis of the head of the femur when the blood supply from the medial and lateral circumflex arteries are disrupted (e.g. through fracture of the neck of the femur along their course). The hip has two anatomically important anastomoses ,
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#17327732256982970-649: A tight ball when threatened. Pangolins have been reported to roll away from danger, by both gravity and self-powered methods. A pangolin in hill country in Sumatra , to flee from a researcher, ran to the edge of a slope and curled into a ball to roll down the slope, crashing through the vegetation, and covering an estimated 30 metres (100 ft) or more in 10 seconds. Caterpillars of the mother-of-pearl moth, Pleuroptya ruralis , when attacked, will touch their heads to their tails and roll backwards, up to 5 revolutions at about 40 centimetres per second (16 in/s), which
3105-404: A transverse axis (left-right); lateral rotation and medial rotation around a longitudinal axis (along the thigh); and abduction and adduction around a sagittal axis (forward-backward); and a combination of these movements (i.e. circumduction , a compound movement in which the leg describes the surface of an irregular cone). Some of the hip muscles also act on either the vertebral joints or
3240-410: A “backward knee”, which is really their ankle. The extension of the joint helps store momentum and acts as a spring, allowing digitigrade creatures more speed. Digitigrade mammals are also often adept at quiet movement. Birds are also digitigrade. Hooved mammals are known as ungulates , walking on the fused tips of their fingers and toes. This can vary from odd-toed ungulates, such as horses, rhinos, and
3375-533: Is chafing , caused by repetitive rubbing of one piece of skin against another, or against an article of clothing. One common location for chafe to occur is the runner's upper thighs. The skin feels coarse and develops a rash-like look. A variety of deodorants and special anti-chafing creams are available to treat such problems. Chafe is also likely to occur on the nipple . There are a variety of home remedies that runners use to deal with chafing while running such as band-aids and using grease to reduce friction. Prevention
3510-420: Is 1.5 body lengths per second (3.5 cm/s or 1.4 in/s). Researchers estimate that the stomatopod acts as a true wheel around 40% of the time during this series of rolls. The remaining 60% of the time it has to "jumpstart" a roll by using its body to thrust itself upwards and forwards. Pangolins have also been reported to roll away from danger by self-powered methods. Witnessed by a lion researcher in
3645-429: Is a popular participatory sport and is one of the events which, along with track and field, road running, and racewalking , makes up the umbrella sport of athletics. The majority of popular races do not incorporate a significant change in elevation as a key component of a course. There are several, disparate variations that feature significant inclines or declines. These fall into two main groups. The naturalistic group
3780-430: Is a thickening of the anterior capsule extending from anterior inferior iliac spine to intertrochanteric line . Ischiofemoral ligament is the thickening of posterior capsule of the hip and pubofemoral ligament is the thickening of the inferior capsule. In the upright position, iliofemoral ligament prevents the trunk from falling backward without the need for muscular activity, thus preventing excessive hyperextension. In
3915-404: Is able to run a certain distance in the shortest time. Today, competitive running events make up the core of the sport of athletics . Events are usually grouped into several classes, each requiring substantially different athletic strengths and involving different tactics, training methods, and types of competitors. Running competitions have probably existed for most of humanity's history and were
4050-531: Is about 40 times its normal speed. Nannosquilla decemspinosa , a species of long-bodied, short-legged mantis shrimp , lives in shallow sandy areas along the Pacific coast of Central and South America. When stranded by a low tide the 3 cm (1.2 in) stomatopod lies on its back and performs backwards somersaults over and over. The animal moves up to 2 metres (6.5 ft) at a time by rolling 20–40 times, with speeds of around 72 revolutions per minute. That
4185-510: Is aided by potential energy , or on loose surfaces (such as sand or scree ), where friction is low but purchase (traction) is difficult. Humans, especially, have adapted to sliding over terrestrial snowpack and terrestrial ice by means of ice skates , snow skis , and toboggans . Aquatic animals adapted to polar climates , such as ice seals and penguins also take advantage of the slipperiness of ice and snow as part of their locomotion repertoire. Beavers are known to take advantage of
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4320-479: Is also turned such that the outer edge of its roof is more lateral than outer edge of the floor. It forms the primary connection between the bones of the lower limb and the axial skeleton of the trunk and pelvis. Both joint surfaces are covered with a strong but lubricated layer called articular hyaline cartilage . The cuplike acetabulum forms at the union of three pelvic bones — the ilium , pubis , and ischium . The Y-shaped growth plate that separates them,
4455-449: Is an angle formed from a vertical line (V) and a line from the centre of the femoral head (C) and the anterior (A) edge of the dense shadow of the subchondral bone slightly posterior to the anterior edge of the acetabulum, with the radiograph being taken from the false angle , that is, a lateral view rotated 25 degrees towards becoming frontal. The articular cartilage angle (AC angle, also called acetabular index or Hilgenreiner angle)
4590-435: Is an angle formed parallel to the weight bearing dome, that is, the acetabular sourcil or "roof", and the horizontal plane, or a line connecting the corner of the triangular cartilage and the lateral acetabular rim. In normal hips in children aged between 11 and 24 months, it has been estimated to be on average 20°, ranging between 18° and 25°. It becomes progressively lower with age. Suggested cutoff values to classify
4725-402: Is attached to the trochanters of the femur and intertrochanteric line anteriorly. Posteriorly, it is attached to a junction between medial two-thirds and lateral one-third of the femoral neck, one finger breadth away from the intertrochanteric crest. From its attachment at the femoral neck, the fibres of the capsule reflected backwards towards the acetabulum, carrying retinacula vessels supplying
4860-545: Is based on outdoor racing over geographical features. Among these are the cross country-related sports of fell running (a tradition associated with Northern Europe) and trail running (mainly ultramarathon distances), the running/climbing combination of skyrunning (organised by the International Skyrunning Federation with races across North America, Europe and East Asia) and the mainly trail- and road-centred mountain running (governed by
4995-419: Is commonly known to stretch before and after a workout session, and also avoid heavy equipment especially during the first couple of workout sessions. Also to help prevent shin splints do not increase the intensity of a workout more than 10% a week. To treat shin splints it is important to rest with the least amount of impact on your legs and apply ice to the area. A survey showed that shin splints make up 12.7% of
5130-422: Is effective on a flat surface and is used for slow, silent movement, such as when stalking prey. Snakes use concertina locomotion for moving slowly in tunnels, here the snake alternates in bracing parts of its body on it surrounds. Finally the caenophidian snakes use the fast and unusual method of movement known as sidewinding on sand or loose soil. The snake cycles through throwing the front part of its body in
5265-415: Is fractured or disrupted by injury in childhood. The hip joint is supplied with blood from the medial circumflex femoral and lateral circumflex femoral arteries, which are both usually branches of the deep artery of the thigh (profunda femoris), but there are numerous variations and one or both may also arise directly from the femoral artery . There is also a small contribution from the foveal artery,
5400-489: Is key which is why form fitting clothes are important. An iliotibial band is a muscle and tendon that is attached to the hip and runs the length of the thigh to attach to the upper part of the tibia, and the band is what helps the knee to bend. This is an injury that is located at the knee and shows symptoms of swelling outside the knee. Iliotibial band syndrome is also known as "runner's knee" or "jogger's knee" because it can be caused by jogging or running. Once pain or swelling
5535-411: Is largely covered by muscles and, as a consequence, the greater trochanter is often the only palpable bony structure in the hip region. The hip joint or coxofemoral joint is a ball and socket synovial joint formed by the articulation of the rounded head of the femur and the cup-like acetabulum of the pelvis. The socket of the acetabulum is pointing downwards and anterolaterally. The socket
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5670-410: Is less opportunity for passive locomotion on land than by sea or air, though parasitism ( hitchhiking ) is available toward this end, as in all other habitats . Many species of monkeys and apes use a form of arboreal locomotion known as brachiation , with forelimbs as the prime mover. Some elements of the gymnastic sport of uneven bars resemble brachiation, but most adult humans do not have
5805-399: Is noticeable it is important to put ice on it immediately and it is recommended to rest the knee for better healing. Most knee injuries can be treated by light activity and much rest for the knee. In more serious cases, arthroscopy is the most common to help repair ligaments but severe situations reconstructive surgery would be needed. A survey was taken in 2011 with knee injuries being 22.7% of
5940-844: Is sunny and warm. Running can improve mental alertness and sleep. Both research and clinical experience have shown that exercise can be a treatment for serious depression and anxiety even some physicians prescribe exercise to most of their patients. Running can have a longer-lasting effect than anti-depressants. The non-threatening environment offered by running generates a sense of achievement and belonging which helps with mental illness. Many injuries are associated with running because of its high-impact nature. Change in running volume may lead to development of patellofemoral pain syndrome , iliotibial band syndrome , patellar tendinopathy , plica syndrome , and medial tibial stress syndrome . Change in running pace may cause Achilles tendinitis , gastrocnemius injuries, and plantar fasciitis . Repetitive stress on
6075-414: Is supported by the legs, is an important aspect. There are three main ways in which vertebrates support themselves with their legs – sprawling, semi-erect, and fully erect. Some animals may use different postures in different circumstances, depending on the posture's mechanical advantages. There is no detectable difference in energetic cost between stances. The "sprawling" posture is the most primitive, and
6210-498: Is that the body adjusts to this flat surface running, and some of the muscles will become weaker, along with the added impact of running on a harder surface. Therefore, it can be beneficial to change terrain occasionally – such as trail, beach, or grass running. This is more unstable ground and allows the legs to strengthen different muscles. Runners should be wary of twisting their ankles on such terrain. Running downhill also increases knee stress and should, therefore, be avoided. Reducing
6345-470: Is the springtail , which while normally hexapedal , hurls itself away from danger using its furcula , a tail -like forked rod that can be rapidly unfurled from the underside of its body. A number of species move and stand on two legs, that is, they are bipedal . The group that is exclusively bipedal is the birds , which have either an alternating or a hopping gait. There are also a number of bipedal mammals . Most of these move by hopping – including
6480-791: Is the maximum speed at which a human can run. It is affected by many factors, varies greatly throughout the population, and is important in athletics and many sports. Air resistance for top sprinters can take up to 5% of their energy. The fastest human footspeed on record is 44.7 km/h (12.4 m/s; 27.8 mph), seen during a 100-meter sprint (average speed between the 60th and the 80th meter) by Usain Bolt . (see Category:Athletics (track and field) record progressions ) Track running events are individual or relay events with athletes racing over specified distances on an oval running track. The events are categorized as sprints , middle and long-distance , and hurdling . Road running takes place on
6615-699: Is the most common gait, where some feet are on the ground at any given time, and found in almost all legged animals. In an informal sense, running is considered to occur when at some points in the stride all feet are off the ground in a moment of suspension . Technically, however, moments of suspension occur in both running gaits (such as trot) and leaping gaits (such as canter and gallop). Gaits involving one or more moments of suspension can be found in many animals, and compared to walking they are faster but more energetically costly forms of locomotion. Animals will use different gaits for different speeds, terrain, and situations. For example, horses show four natural gaits,
6750-539: Is the original limb posture from which the others evolved. The upper limbs are typically held horizontally, while the lower limbs are vertical, though upper limb angle may be substantially increased in large animals. The body may drag along the ground, as in salamanders, or may be substantially elevated, as in monitor lizards . This posture is typically associated with trotting gaits , and the body flexes from side-to-side during movement to increase step length. All limbed reptiles and salamanders use this posture, as does
6885-579: Is the study of gait in humans and other animals. This may involve videoing subjects with markers on particular anatomical landmarks and measuring the forces of their footfall using floor transducers ( strain gauges ). Skin electrodes may also be used to measure muscle activity. There are a number of terrestrial and amphibious limbless vertebrates and invertebrates. These animals, due to lack of appendages, use their bodies to generate propulsive force. These movements are sometimes referred to as "slithering" or "crawling", although neither are formally used in
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#17327732256987020-492: Is too exhausted to flee, succumbing to "chase myopathy " (Sears 2001), and that human features such as the nuchal ligament , abundant sweat glands , the Achilles tendons , big knee joints and muscular glutei maximi , were changes caused by this type of activity (Bramble & Lieberman 2004, et al.). The theory as first proposed used comparative physiological evidence and the natural habits of animals when running, indicating
7155-676: The East African Rift in Africa. The Tailteann Games , an Irish sporting festival in honor of the goddess Tailtiu , dates back to 1829 BCE and is one of the earliest records of competitive running. The origins of the Olympics and Marathon running are shrouded by myth and legend, though the first recorded games took place in 776 BCE. Running in Ancient Greece can be traced back to these games of 776 BCE. ...I suspect that
7290-554: The Namib desert, will actively roll down sand dunes. This action can be used to successfully escape predators such as the Pompilidae tarantula wasps , which lay their eggs in a paralyzed spider for their larvae to feed on when they hatch. The spiders flip their body sideways and then cartwheel over their bent legs. The rotation is fast, the golden wheel spider ( Carparachne aureoflava ) moving up to 20 revolutions per second, moving
7425-507: The Serengeti in Africa, a group of lions surrounded a pangolin, but could not get purchase on it when it rolled into a ball, and so the lions sat around it waiting and dozing. Surrounded by lions, it would unroll itself slightly and give itself a push to roll some distance, until by doing this multiple times it could get far enough away from the lions to be safe. Moving like this would allow a pangolin to cover distance while still remaining in
7560-549: The Sierra Nevada mountains. When disturbed or startled it coils itself up into a ball, often causing it to roll downhill. The pebble toad ( Oreophrynella nigra ) lives atop tepui in the Guiana highlands of South America . When threatened, often by tarantulas , it rolls into ball, and typically being on an incline, rolls away under gravity like a loose pebble. Namib wheeling spiders ( Carparachne spp. ), found in
7695-578: The World Mountain Running Association and based mainly in Europe). Terrestrial locomotion As viewed from evolutionary taxonomy , there are three basic forms of animal locomotion in the terrestrial environment: Some terrains and terrestrial surfaces permit or demand alternative locomotive styles. A sliding component to locomotion becomes possible on slippery surfaces (such as ice and snow ), where location
7830-422: The acetabular labrum . Excessive coverage of femoral head by the acetabulum can lead to pincer-type femoro-acetabular impingement (FAI). In humans, unlike other animals, the hip bones are substantially different in the two sexes. The hips of human females widen during puberty . The femora are also more widely spaced in females, so as to widen the opening in the hip bone and thus facilitate childbirth. Finally,
7965-458: The cruciate and the trochanteric anastomoses , the latter of which provides most of the blood to the head of the femur. These anastomoses exist between the femoral artery or profunda femoris and the gluteal vessels. The hip muscles act on three mutually perpendicular main axes, all of which pass through the center of the femoral head , resulting in three degrees of freedom and three pair of principal directions: Flexion and extension around
8100-695: The foot is attached. Within this form there is much variation in structure and shape. An alternative form of vertebrate 'leg' to the tetrapod leg is the fins found on amphibious fish . Also a few tetrapods , such as the macropods , have adapted their tails as additional locomotory appendages. The fundamental form of the vertebrate foot has five digits, however some animals have fused digits, giving them less, and some early fishapods had more; Acanthostega had eight toes. Only ichthyosaurs evolved more than 5 digits within tetrapods, while their transition from land to water again (limb terminations were becoming flippers). Feet have evolved many forms depending on
8235-421: The hip , or coxa ( pl. : coxae ) in medical terminology , refers to either an anatomical region or a joint on the outer (lateral) side of the pelvis . The hip region is located lateral and anterior to the gluteal region , inferior to the iliac crest , and lateral to the obturator foramen , with muscle tendons and soft tissues overlying the greater trochanter of the femur . In adults,
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#17327732256988370-457: The iliofemoral , ischiofemoral , and pubofemoral ligaments attached to the bones of the pelvis (the ilium , ischium , and pubis respectively). All three strengthen the capsule and prevent an excessive range of movement in the joint. Of these, the Y-shaped and twisted iliofemoral ligament is the strongest ligament in the human body. It has a tensile strength of 350 kg. Iliofemoral ligament
8505-716: The immune system and an improved self-esteem and emotional state. Running, like all forms of regular exercise, can effectively slow or reverse the effects of aging. Even people who have already experienced a heart attack are 20% less likely to develop serious heart problems if more engaged in running or any type of aerobic activity. Although an optimal amount of vigorous aerobic exercise such as running might bring benefits related to lower cardiovascular disease and life extension, an excessive dose (e.g., marathons ) might have an opposite effect associated with cardiotoxicity . Running can assist people in losing weight, staying in shape and improving body composition. Research suggests that
8640-454: The macropods such as kangaroos and various jumping rodents . Only a few mammals such as humans and the ground pangolin commonly show an alternating bipedal gait. In humans, alternating bipedalism is characterized by a bobbing motion, which is due to the utilization of gravity when falling forward. This form of bipedalism has demonstrated significant energy savings. Cockroaches and some lizards may also run on their two hind legs. With
8775-426: The pelvic inclination angle . Pain of the hip may be the result of numerous causes, including nervous, osteoarthritic, infectious, traumatic, and genetic. The hip joint, also known as a ball and socket joint, is formed by the acetabulum of the pelvis and the femoral head, which is the top portion of the thigh bone (femur). It allows for a wide range of movement and stability in the lower body. The proximal femur
8910-419: The platypus and several species of frogs that walk. Unusual examples can be found among amphibious fish , such as the mudskipper , which drag themselves across land on their sturdy fins. Among the invertebrates , most arthropods – which includes the most diverse group of animals, the insects – have a stance best described as sprawling. There is also anecdotal evidence that some octopus species (such as
9045-473: The sacroiliac joint meander and criss-cross each other down through the hip bone, the femoral head, neck, and shaft. On the lateral side of the hip joint the fascia lata is strengthened to form the iliotibial tract which functions as a tension band and reduces the bending loads on the proximal part of the femur. Proximally, capsule of the hip joint is attached to the edge of the acetabulum, acetabular labrum, and transverse acetabular ligament. Distally, it
9180-415: The triradiate cartilage , is fused definitively at ages 14–16. It is a special type of spheroidal or ball and socket joint where the roughly spherical femoral head is largely contained within the acetabulum and has an average radius of curvature of 2.5 cm. The acetabulum grasps almost half the femoral ball, a grip deepened by a ring-shaped fibrocartilaginous lip, the acetabular labrum , which extends
9315-405: The vertebrates and the arthropods . Important aspects of legged locomotion are posture (the way the body is supported by the legs), the number of legs, and the functional structure of the leg and foot . There are also many gaits , ways of moving the legs to locomote, such as walking , running , or jumping . Appendages can be used for movement in a lot of ways: the posture, the way the body
9450-428: The absorption phases of running. The propulsion phase, which occurs from midstance to toe-off, is crucial for understanding how the body moves forward. In a full stride length model, elements of both the terminal swing and footstrike contribute to propulsion. The setup for propulsion begins at the end of the terminal swing when the hip joint flexes, allowing the hip extensors to generate force as they accelerate through
9585-528: The ancestors of humankind developed the ability to run for long distances about 2.6 million years ago, probably to hunt animals . Competitive running grew out of religious festivals in various areas. Records of competitive racing date back to the Tailteann Games in Ireland between 632 BCE and 1171 BCE, while the first recorded Olympic Games took place in 776 BCE. Running has been described as
9720-416: The angle as abnormally increased include: The angle between the longitudinal axes of the femoral neck and shaft, called the caput-collum-diaphyseal angle or CCD angle, normally measures approximately 150° in newborn and 126° in adults ( coxa norma ). An abnormally small angle is known as coxa vara and an abnormally large angle as coxa valga . Because changes in shape of the femur naturally affects
9855-429: The animal's needs. One key variation is where on the foot the animal's weight is placed. Some vertebrates: amphibians, reptiles, and some mammals such as humans , bears , and rodents, are plantigrade. This means the weight of the body is placed on the heel of the foot, giving it strength and stability. Most mammals, such as cats and dogs , are digitigrade , walking on their toes, giving them what many people mistake as
9990-404: The ankle joint. On the other hand, a mid/forefoot strike helps in shock absorption, supporting plantar flexion from midstance to toe-off. Actual propulsion begins as the lower extremity enters midstance. The hip extensors continue contracting, assisted by gravity and the stretch reflex from maximal hip flexion during the terminal swing. Hip extension pulls the ground underneath the body, propelling
10125-457: The ankle undergoes plantar flexion. Propulsion continues until the leg is extended behind the body and toe-off occurs. This involves a maximal hip extension, knee extension, and plantar flexion for the subject, resulting in the body being pushed forward from this motion, and the ankle/foot leaves the ground as the initial swing begins. Research, especially in the footstrike debate, has primarily focused on identifying and preventing injuries during
10260-451: The ball of the foot, ball and heel of the foot simultaneously and heel of the foot respectively. During this time, the hip joint is undergoing extension from being in maximal flexion from the previous swing phase. For proper force absorption, the knee joint should be flexed upon the footstrike, and the ankle should be slightly in front of the body. Footstrike begins the absorption phase as forces from initial contact are attenuated throughout
10395-447: The beginning of the initial swing of one side, there is a flight phase where neither extremity is in contact with the ground due to the opposite side finishing terminal swing. As the footstrike of the one hand occurs, the initial swing continues. The opposing limbs meet with one in midstance and midswing, beginning the propulsion and terminal swing phases. The upper extremity function serves mainly in providing balance in conjunction with
10530-410: The body. Hip flexion and knee flexion occur, beginning the return of the limb to the starting position and setting up for another foot strike. The initial swing ends at midswing when the limb is again directly underneath the trunk, pelvis, and hip with the knee joint flexed and hip flexion continuing. Terminal swing then begins as hip flexion continues to the point of activation of the stretch reflex of
10665-429: The chin up and scrunching shoulders. Exercise physiologists have found that the stride rates are extremely consistent across professional runners, between 185 and 200 steps per minute. The main difference between long- and short-distance runners is the length of stride rather than the rate of stride. During running, the speed at which the runner moves may be calculated by multiplying the cadence (steps per minute) by
10800-447: The continuous nature of running gait, no certain point is assumed to be the beginning. However, for simplicity, it will be assumed that absorption and footstrike mark the beginning of the running cycle in a body already in motion. Footstrike occurs when a plantar portion of the foot makes initial contact with the ground. Common footstrike types include forefoot, midfoot, and heel strike types. These are characterized by initial contact of
10935-495: The differences in the potential injury risks and shock absorption capabilities between heel and mid/forefoot footstrikes. It has been shown that heel striking is generally associated with higher rates of injury and impact due to inefficient shock absorption and inefficient biomechanical compensations for these forces. This is due to pressures from a heel strike traveling through bones for shock absorption rather than being absorbed by muscles. Since bones cannot disperse forces easily,
11070-454: The direction of motion and bringing the back part of its body into line crosswise. Although animals have never evolved wheels for locomotion, a small number of animals will move at times by rolling their whole body. Rolling animals can be divided into those that roll under the force of gravity or wind and those that roll using their own power. The web-toed salamander , a 10-centimetre (3.9 in) salamander, lives on steep hills in
11205-400: The exception of the birds, terrestrial vertebrate groups with legs are mostly quadrupedal – the mammals, reptiles , and the amphibians usually move on four legs. There are many quadrupedal gaits. The most diverse group of animals on earth, the insects , are included in a larger taxon known as hexapods , most of which are hexapedal, walking and standing on six legs. Exceptions among
11340-877: The faster speeds of elite runners compared to recreational runners with similar footstrikes to physiological differences, the hip, and joints have been left out of the equation for proper propulsion. This raises the question of how heel-striking elite distance runners can keep up such high paces with a supposedly inefficient and injurious foot strike technique. Biomechanical factors associated with elite runners include increased hip function, use, and stride length over recreational runners. An increase in running speeds causes increased ground reaction forces, and elite distance runners must compensate for this to maintain their pace over long distances. These forces are attenuated through increased stride length via increased hip flexion and extension through decreased ground contact time and more energy being used in propulsion. With increased propulsion in
11475-518: The femoral head. The part of femoral neck outside the capsule is shorter in front than posteriorly. The strong but loose fibrous capsule of the hip joint permits the hip joint to have the second largest range of movement (second only to the shoulder ) and yet support the weight of the body, arms and head. The capsule has two sets of fibers: longitudinal and circular. The hip joint is reinforced by four ligaments, of which three are extracapsular and one intracapsular. The extracapsular ligaments are
11610-418: The femur is attached to the shaft by a thin neck region that is often prone to fracture in the elderly, which is mainly due to the degenerative effects of osteoporosis . The acetabulum is oriented inferiorly, laterally and anteriorly, while the femoral neck is directed superiorly, medially, and slightly anteriorly. Acetabular angle (or Sharp's angle) is the angle between the horizontal line passing through
11745-437: The forces are transmitted to other parts of the body, including ligaments, joints, and bones in the rest of the lower extremities up to the lower back. This causes the body to use abnormal compensatory motions in an attempt to avoid serious bone injuries. These compensations include internal rotation of the tibia, knee, and hip joints. Excessive compensation over time has been linked to a higher risk of injuries in those joints and
11880-430: The frequency and duration can also prevent injury. Barefoot running has been promoted as a means of reducing running related injuries, but this remains controversial and a majority of professionals advocate the wearing of appropriate shoes as the best method for avoiding injury. However, a study in 2013 concluded that wearing neutral shoes is not associated with increased injuries. Another common, running-related injury
12015-451: The genus Pinnoctopus ) can also drag themselves across land a short distance by hauling their body along by their tentacles (for example to pursue prey between rockpools) – there may be video evidence of this. The semi-erect posture is more accurately interpreted as an extremely elevated sprawling posture. This mode of locomotion is typically found in large lizards such as monitor lizards and tegus . Mammals and birds typically have
12150-401: The ground, returning from dorsiflexion in midstance. This can occur either by releasing the elastic load from an earlier mid/forefoot strike or through concentric contraction from a heel strike. With a forefoot strike, the ankle and knee joints release their stored elastic energy from the footstrike/absorption phase. The quadriceps group/knee extensors fully extend the knee, pushing the body off
12285-409: The ground. Simultaneously, the knee flexors and stretch reflex pull the knee back into flexion, initiating the initial swing phase. The hip extensors extend to the maximum, contributing to forces pulling and pushing off the ground, as well as initiating knee flexion and the initial swing phase. Initial swing is the response of both stretch reflexes and concentric movements to the propulsion movements of
12420-407: The head). It is only stretched when the hip is dislocated, and may then prevent further displacement. It is not that important as a ligament but can often be vitally important as a conduit of a small artery to the head of the femur, that is, the foveal artery . This artery is not present in everyone but can become the only blood supply to the bone in the head of the femur when the neck of the femur
12555-469: The heel and facilitates the use of the spring mechanism of the foot. Additionally, it facilitates avoiding the braking effect that occurs when a runner lands their foot in front of the center of mass. Although maintaining an upright posture is crucial, runners should also keep their frame relaxed and engage their core to keep their posture stable. This helps prevent injury as long as the body is neither rigid nor tense. The most common running mistakes are tilting
12690-671: The hind legs of kangaroos are very elastic , allowing kangaroos to effectively bounce along conserving energy from hop to hop, making saltation a very energy efficient way to move around in their nutrient poor environment. Saltation is also used by many small birds, frogs , fleas , crickets , grasshoppers , and water fleas (a small planktonic crustacean ). Most animals move in the direction of their head. However, there are some exceptions. Crabs move sideways, and naked mole rats , which live in tight tunnels and can move backward or forward with equal facility. Crayfish can move backward much faster than they can move forward. Gait analysis
12825-431: The hip extensors. The knee begins to extend slightly as it swings to the anterior portion of the body. The foot then makes contact with the ground with a foot strike, completing the running cycle of one side of the lower extremity. Each limb of the lower extremity works opposite to the other. When one side is in toe-off/propulsion, the other hand is in the swing/recovery phase preparing for footstrike. Following toe-off and
12960-403: The hip joint is thus performed by a series of muscles which are here presented in order of importance with the range of motion from the neutral zero-degree position indicated: A hip fracture is a break that occurs in the upper part of the femur. Symptoms may include pain around the hip particularly with movement and shortening of the leg. The hip joint can be replaced by a prosthesis in
13095-400: The horizontal plane, less impact occurs from the decreased force in the vertical plane. Increased hip flexion allows for increased use of the hip extensors through midstance and toe-off, allowing for more force production. The difference even between world-class and national-level 1500-m runners has been associated with more efficient hip joint function. The increase in velocity likely comes from
13230-457: The ilium and its muscle attachment are shaped so as to situate the buttocks away from the birth canal, where contraction of the buttocks could otherwise damage the baby. The female hips have long been associated with both fertility and general expression of sexuality . Since broad hips facilitate childbirth and also serve as an anatomical cue of sexual maturity, they have been seen as an attractive trait for women for thousands of years. Many of
13365-677: The increased range of motion in hip flexion and extension, allowing for greater acceleration and speed. The hip extensors and extension have been linked to more powerful knee extension during toe-off, contributing to propulsion. Stride length must be appropriately increased with some degree of knee flexion maintained through the terminal swing phases, as excessive knee extension during this phase along with footstrike has been associated with higher impact forces due to braking and an increased prevalence of heel striking. Elite runners tend to exhibit some degree of knee flexion at footstrike and midstance, which first serves to eccentrically absorb impact forces in
13500-412: The inferior aspects of triradiate cartilages ( Hilgenreiner's line ) and another line passing through the inferior angle of triradiate cartilage to superior acetabular rim. The angle measures 35 degrees at birth, 25 degrees at one year of age, and less than 10 degrees by 15 years of age. In adults the angle can vary from 33 to 38 degrees. The sagittal angle of the acetabular inlet is an angle between
13635-572: The insects include praying mantises and water scorpions , which are quadrupeds with their front two legs modified for grasping, some butterflies such as the Lycaenidae (blues and hairstreaks) which use only four legs, and some kinds of insect larvae that may have no legs (e.g., maggots ), or additional prolegs (e.g., caterpillars ). Spiders and many of their relatives move on eight legs – they are octopedal . However, some creatures move on many more legs. Terrestrial crustaceans may have
13770-401: The joint beyond the equator. The centre of the acetabulum (fovea) does not articulate to anything. Instead, it is lined with fat pad and attached to ligamentum teres . The acetabular labrum is horse-shoe shaped. Its inferior notch is bridged by transverse acetabular ligament. The joint space between the femoral head and the superior acetabulum is normally between 2 and 7 mm. The head of
13905-432: The knee joint, that with their extensive areas of origin and/or insertion, different part of individual muscles participate in very different movements, and that the range of movement varies with the position of the hip joint. Additionally, the inferior and Superior gemelli muscles assist the obturator internus and the three muscles together form the three-headed muscle known as the triceps coxae . The movements of
14040-460: The knee, coxa valga is often combined with genu varum (bow-leggedness), while coxa vara leads to genu valgum (knock-knees). Changes in the CCD angle is the result of changes in the stress patterns applied to the hip joint. Such changes, caused for example by a dislocation, change the trabecular patterns inside the bones. Two continuous trabecular systems emerging on the auricular surface of
14175-507: The least misstep could lead to a fatal fall . Many species of animals must sometimes locomote while safely conveying their young. Most often this task is performed by adult females. Some species are specially adapted to conveying their young without occupying their limbs, such as marsupials with their special pouch. In other species, the young are carried on the mother's back, and the offspring have instinctual clinging behaviours. Many species incorporate specialized transportation behaviours as
14310-412: The leg waves travelling forward as they walk, while larger centipedes move with the leg waves travelling backward. The legs of tetrapods , the main group of terrestrial vertebrates (which also includes amphibious fish ), have internal bones, with externally attached muscles for movement, and the basic form has three key joints : the shoulder joint, the knee joint, and the ankle joint, at which
14445-565: The likelihood of this activity as a successful hunting method. Further evidence from observation of modern-day hunting practices also indicated this likelihood (Carrier et al. 1984). According to Sears (p. 12) scientific investigation (Walker & Leakey 1993) of the Nariokotome skeleton provided further evidence for the Carrier theory. Competitive running grew out of religious festivals in various areas such as Greece, Egypt, Asia, and
14580-412: The lower extremity. Absorption of forces continues as the body moves from footstrike to midstance due to vertical propulsion from the toe-off during a previous gait cycle. Midstance is when the lower extremity limb of focus is in knee flexion directly underneath the trunk, pelvis, and hips. At this point, propulsion begins to occur as the hips undergo hip extension, the knee joint undergoes extension, and
14715-449: The maximal range of motion. As the hip extensors transition from inhibitory to primary muscle movers, the lower extremity moves back towards the ground, aided by the stretch reflex and gravity. The footstrike and absorption phases follow, leading to two possible outcomes. With a heel strike, this phase may be just a continuation of momentum from the stretch reflex, gravity, and light hip extension, offering little force absorption through
14850-408: The most common injuries in running, with blisters being the top percentage at 30.9%. Running is both a competition and a type of training for sports that have running or endurance components. As a sport, it is split into events divided by distance and sometimes includes permutations such as the obstacles in steeplechase and hurdles . Running races are contests to determine which of the competitors
14985-455: The most common injuries. A more known injury is medial tibial stress syndrome (MTSS) which is the accurate name for shin splints. This is caused during running when the muscle is being overused along the front of the lower leg with symptoms that affect 2 to 6 inches of the muscle. Shin splints have sharp, splinter-like pain, that is typically X-rayed by doctors but is not necessary for shin splints to be diagnosed. To help prevent shin splints it
15120-449: The most legs are the millipedes . They have two pairs of legs per body segment, with common species having between 80 and 400 legs overall – with the rare species Illacme plenipes having up to 750 legs. Animals with many legs typically move them in metachronal rhythm , which gives the appearance of waves of motion travelling forward or backward along their rows of legs. Millipedes, caterpillars, and some small centipedes move with
15255-540: The motion of legs on either side of the body alternates, i.e. is out of phase. Other animals, such as a horse when galloping, or an inchworm , alternate between their front and back legs. In saltation (hopping) all legs move together, instead of alternating. As a main means of locomotion, this is usually found in bipeds, or semi-bipeds. Among the mammals saltation is commonly used among kangaroos and their relatives, jerboas , springhares , kangaroo rats , hopping mice , gerbils , and sportive lemurs . Certain tendons in
15390-488: The muscles involved in those motions. Conversely, a mid/forefoot strike has been associated with greater efficiency and lower injury risk due to the triceps surae being used as a lever system to absorb forces with the muscles eccentrically rather than through the bone. Landing with a mid/forefoot strike has also been shown to properly attenuate shock and allow the triceps surae to aid in propulsion via reflexive plantarflexion after stretching to absorb ground contact forces. Thus
15525-498: The number of newly created neurons within the brain. This finding could have significant implications in aging as well as learning and memory. A recent study published in Cell Metabolism has also linked running with improved memory and learning skills. Running is an effective way to reduce stress, anxiety, depression, and inflammation. It helps people who struggle with seasonal affective disorder by running outside when it
15660-472: The opposing side of the lower extremity. The movement of each leg is paired with the opposite arm, which serves to counterbalance the body, particularly during the stance phase. The arms move most effectively (as seen in elite athletes) with the elbow joint at approximately 90 degrees or less, the hands swinging from the hips up to mid-chest level with the opposite leg, the Humerus moving from being parallel with
15795-573: The opposite direction to motion, known as retrograde waves , or in the same direction as motion, known as direct waves. Earthworms move by retrograde waves alternatively swelling and contracting down the length of their body, the swollen sections being held in place using setae . Aquatic molluscs such as limpets , which are sometimes out of the water, tend to move using retrograde waves. However, terrestrial molluscs such as slugs and snails tend to use direct waves. Lugworms and seals also use direct waves. Most snakes move using lateral undulation where
15930-402: The person of average weight will burn approximately 100 calories per mile run. Running increases one's metabolism , even after running; one will continue to burn an increased level of calories for a short time after the run. Different speeds and distances are appropriate for different individual health and fitness levels. For new runners, it takes time to get into shape. The key is consistency and
16065-426: The potential for injury while running (just as there is in any sport), there are many benefits. Some of these benefits include potential weight loss , improved cardiovascular and respiratory health (reducing the risk of cardiovascular and respiratory diseases), improved cardiovascular fitness, reduced total blood cholesterol , strengthening of bones (and potentially increased bone density), possible strengthening of
16200-455: The quadriceps muscle group. Secondly it allows for the knee joint to contract concentrically and provides significant aid in propulsion during toe-off as the quadriceps group is capable of producing large amounts of force. Recreational runners have been shown to increase stride length through increased knee extension rather than increased hip flexion, as exhibited by elite runners, which provides an intense braking motion with each step and decreases
16335-405: The rate and efficiency of knee extension during toe-off, slowing down speed. Knee extension, however, contributes to additional stride length and propulsion during toe-off and is seen more frequently in elite runners as well. ‹The template How-to is being considered for merging .› Leaning forward places a runner's center of mass on the front part of the foot, which avoids landing on
16470-530: The rear end and then moving forward the front end, which is then anchored and then the back end is pulled in, and so on. This is known as two-anchor movement . A legged animal, the inchworm , also moves like this, clasping with appendages at either end of its body. Limbless animals can also move using pedal locomotory waves , rippling the underside of the body. This is the main method used by molluscs such as slugs and snails, and also large flatworms, some other worms, and even earless seals . The waves may move in
16605-461: The runner forward. During midstance, the knee should be slightly flexed due to elastic loading from the absorption and footstrike phases, preserving forward momentum. The ankle joint is in dorsiflexion at this point, either elastically loaded from a mid/forefoot strike or preparing for stand-alone concentric plantar flexion. The final propulsive movements during toe-off involve all three joints: ankle, knee, and hip. The plantar flexors push off from
16740-502: The same tissues without enough time for recovery or running with improper form can lead to many of the above. Runners generally attempt to minimize these injuries by warming up before exercise, focusing on proper running form, performing strength training exercises, eating a well balanced diet, allowing time for recovery, and "icing" (applying ice to sore muscles or taking an ice bath). Some runners may experience injuries when running on concrete surfaces. The problem with running on concrete
16875-548: The scientific literature and the latter term is also used for some animals moving on all four limbs. All limbless animals come from cold-blooded groups; there are no endothermic limbless animals, i.e. there are no limbless birds or mammals. Where the foot is important to the legged mammal, for limbless animals the underside of the body is important. Some animals such as snakes or legless lizards move on their smooth dry underside. Other animals have various features that aid movement. Molluscs such as slugs and snails move on
17010-423: The sitting position, it becomes relaxed, thus permitting the pelvis to tilt backward into its sitting position. Ischiofemoral prevents excessive extension and the pubofemoral ligament prevents excess abduction and extension. The zona orbicularis , which lies like a collar around the most narrow part of the femoral neck , is covered by the other ligaments which partly radiate into it. The zona orbicularis acts like
17145-472: The slowest horse gait is the walk , then there are three faster gaits which, from slowest to fastest, are the trot , the canter , and the gallop . Animals may also have unusual gaits that are used occasionally, such as for moving sideways or backwards. For example, the main human gaits are bipedal walking and running , but they employ many other gaits occasionally, including a four-legged crawl in tight spaces. In walking, and for many animals running,
17280-429: The spider at 1 metre per second (3.3 ft/s). Coastal tiger beetle larvae when threatened can flick themselves into the air and curl their bodies to form a wheels, which the wind blows, often uphill, as far as 25 m (80 ft) and as fast as 11 km/h (3 m/s; 7 mph). They also may have some ability to steer themselves in this state. Pangolins , a type of mammal covered in thick scales, roll into
17415-415: The sport report feeling an elated, euphoric state, often referred to as a " runner's high ". Running is frequently recommended as therapy for people with clinical depression and people coping with addiction. A possible benefit may be the enjoyment of nature and scenery, which also improves psychological well-being (see Ecopsychology § Practical benefits ). In animal models, running has been shown to increase
17550-576: The stride length. Running is often measured in terms of pace , expressed in units of minutes per mile or minutes per kilometer (the inverse of speed, in mph or km/h). Some coaches advocate training at a combination of specific paces related to one's fitness to stimulate various physiological improvements. Different types of stride are necessary for different types of running. When sprinting, runners stay on their toes bringing their legs up, using shorter and faster strides. Long-distance runners tend to have more relaxed strides that vary. While there exists
17685-463: The sun, moon, earth, stars, and heaven, which are still the gods of many barbarians, were the only gods known to the aboriginal Hellenes. Seeing that they were always moving and running, from their running nature they were called gods or runners (Thus, Theontas)... Running gait can be divided into two phases regarding the lower extremity : stance and swing. These can be further divided into absorption, propulsion, initial swing, and terminal swing. Due to
17820-557: The three pelvic bones ( ilium , ischium and pubis ) have fused into one hip bone , which forms the superomedial/deep wall of the hip region. The hip joint , scientifically referred to as the acetabulofemoral joint ( art. coxae ), is the ball-and-socket joint between the pelvic acetabulum and the femoral head . Its primary function is to support the weight of the torso in both static (e.g. standing ) and dynamic (e.g. walking or running ) postures. The hip joints have very important roles in retaining balance, and for maintaining
17955-519: The trunk to approximately 45 degrees shoulder extension (never passing the trunk in flexion) and with as little movement in the transverse plane as possible. The trunk also rotates in conjunction with arm swing. It mainly serves as a balance point from which the limbs are anchored. Thus trunk motion should remain mostly stable with little motion except for slight rotation, as excessive movement would contribute to transverse motion and wasted energy. Recent research into various forms of running has focused on
18090-412: The upper body strength required to sustain brachiation. Many other species of arboreal animal with tails will incorporate their tails into the locomotion repertoire, if only as a minor component of their suspensory behaviors . Locomotion on irregular, steep surfaces require agility and dynamic balance known as sure-footedness . Mountain goats are famed for navigating vertiginous mountainsides where
18225-401: The world's most accessible sport. It is thought that human running evolved at least four and a half million years ago out of the ability of the ape-like Australopithecus , an early ancestor of humans, to walk upright on two legs . Early humans most likely developed into endurance runners from the practice of persistence hunting of animals, the activity of following and chasing until a prey
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