Running

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Running

Running

Red wolf running. Running is a means for an animal to move on foot. It is defined in sporting terms as a gait in which at some point all feet are off the ground at the same time. 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 rides along fairly smoothly on top of the legs. The term running can refer to any of a variety of speeds ranging from jogging to sprinting.

Motion
Humans actually leap from one leg to the other while running. Each leap raises the center of gravity during take-off, and lowers it on landing as the knee bends to absorb the shock. At mid arc, both feet are momentarily off of the ground. This continual rise and fall of bodyweight expends a tremendous amount of energy opposing gravity and absorbing shock during take-off and landing. Running uses more energy than walking to travel the same distance. [1] Therefore, running is less efficient than walking in terms of calories expended per unit distance, though it is faster.

Jeanette Kwakye during World Indoor Championships 2008 in Valencia on the ground at a time in running, one leg is always in recovery, while the other goes through support and drive. Then, briefly, as the runner leaps through the air, both legs are in recovery. These phases are described in detail below.

Support
During the support phase, the foot is in contact with the ground and supports the body against gravity. The body’s centre of mass is typically somewhere in the lower abdominal area between the hips. The supporting foot touches ground slightly ahead of the point that lies directly below the body’s centre of mass. The knee joint is at its greatest extension just prior to the support phase; when contact is made with the ground, the knee joint begins to flex. To what extent it flexes varies with the running style. There exist stiff-legged running styles which reduce knee

Lower body motion
Running is executed as a sequence of strides, which alternate between the two legs. Each leg’s stride can be roughly divided into three phases: support, drive, and recovery. Support and drive occur when the foot is in contact with the ground. Recovery occurs when the foot is off the ground. Since only one foot is

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flexion, and looser, or more dynamic running styles which increase it. As the supporting leg bends at the knee, the pelvis dips down on the opposite side. These motions absorb shock and are opposed by the coordinated action of several muscles. The pelvic dip is opposed by the Tensor fasciae lataeilio-tibial band of the supporting leg, the hip abductor, and the abdominals and lower back muscles. The knee flexion is opposed by the Muscle contraction eccentric contraction of the quadriceps muscle. The supporting hip continues to extend and the body’s centre of mass passes over the supporting leg. The knee then begins to extend, and the opposite hip rises from its brief dip. The support phase begins to transition into drive.

Running
upward. The degree of leg lift can be consciously adjusted by the runner, with additional muscle power. During the last stage of recovery, the hip achieves maximal flexion, and, as the lower leg rapidly unfolds, which it does in a passive way, the knee joint also reaches its greatest, though not full, extension. During this extension of the leg and flexion of the hip, the hamstring and gluteal muscles are required to stretch rapidly. Muscles which are stretched respond by contracting by a reflex action. Recovery ends when the foot comes into contact with the ground, transitioning again into the support phase.

Upper body motion
The motions of the upper body are essential to maintaining balance, and a forward motion for optimal running. They compensate for the motions of the lower body, keeping the body in rotational balance. A leg’s recovery is matched by a forward drive of the opposite arm, and a leg’s support and drive motions are balanced by backward movement of the opposite arm. The shoulders and torso are also involved. Because the leg drive is slower than the kick of recovery, the arm thrusting backward is slower also. The forward arm drive is more forceful and rapid. The more force exerted by the lower body, the more exaggerated do the upper body motions have to be to absorb the momentum. While it is possible to run without movements of the arms, the spine and shoulders will generally still be recruited. Using the arms to absorb the forces aids in maintaining balance at higher speed. Otherwise, optimal force would be hard to attain for fear of falling over. Most of the energy expended in running goes to the compensating motions, and so considerable gains in running speed as well as economy can be made by eliminating wasteful or incorrect motions. For instance, if the force vector in the drive phase is aimed too far away from the centre of mass of the body, it will transfer an angular momentum to the body which has to be absorbed. The faster the running, the more energy has to be dissipated through compensating motions throughout the entire body. This is why elite sprinters have powerful upper body physiques. As the competitive distance increases, there is a rapid drop in the upper body and overall muscle mass typically

Drive
The support phase quickly transitions into the drive phase. The drive leg extends at the knee joint, and at the hips, such that the toe maintains contact with the ground as that leg trails behind the body. The foot pushes backward and also down, creating a diagonal force vector, which, in an efficient running style, is aimed squarely at the runner’s centre of mass. Since the diagonal vector has a vertical component, the drive phase continues to provide some support against gravity and can be regarded as an extension of the support phase. During the drive, the foot may extend also, by a flexing of the soleus and gastrocnemius muscle in the calf. In some running styles, notably long-distance "shuffles" which keep the feet close to the ground, the ankle remains more or less rigid during drive. Because the knee joint straightens, though not completely, much of the power of the drive comes from the quadriceps muscle group, and in some running styles, additional power comes from the calves as they extend the foot for a longer drive. This motion is most exhibited in sprinting.

Recovery
When the driving toe loses contact with the ground, the recovery phase begins. During recovery, the hip flexes, which rapidly drives the knee forward. Much of the motion of the lower leg is driven by the forces transferred from the upper leg rather than by the action of the muscles. As the knee kicks forward, it exerts torque against the lower leg through the knee joint, causing the leg to snap

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exhibited by the people who compete at a high level in each respective event. Long distance runners typically have lean muscles. It should also be noted that the upper body also helps to propel the body up hills. The faster one swings their arms up a hill, the faster the person will move up the hill because the legs will match the speed at which the arms are moving.

Running
the length of stride rather than the rate of stride.[2][3] During running, the speed at which the runner moves may be calculated by multiplying the cadence (steps per second) by the stride length. Running is often measured in terms of pace[4] in minutes per mile or kilometer. Fast stride rates coincide with the rate one pumps their arms. The faster one’s arms move up and down, parallel with the body, the faster the rate of stride. 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.

Elements of good running technique

Running injuries
Because of its high-impact nature, many injuries are associated with running. They include "runner’s knee" (pain in the knee), shin splints, pulled muscles (especially the hamstring), twisted ankles, iliotibial band syndrome, plantar fasciitis, runners bladder, and Achilles tendinitis. Stress fractures are also fairly common in runners training at a high volume or intensity. The most common running-related injuries are due to over-exertion or bad running form. Repetitive stress on the same tissues without enough time for recovery or running with improper form can lead to many of the above. Generally these injuries can be minimized by warming up beforehand,[5] improving running form, performing strength training exercises, eating a well balanced diet, getting enough rest, and "icing" (applying ice to sore muscles or taking an ice bath). Foot blisters are also common among runners. Specialized socks help to prevent blisters greatly. For existing cases, lancing the blister with a sterile needle and applying a cyanoacrylate glue (such as Superglue or Krazy Glue) may help to protect the wound and enable further running. This is common practice among hardened endurance atheletes.[6] For the prevention of jogger’s nipple, there are many commercial products available. A common solution is to simply affix a piece of medical tape over each nipple before running.[7] Another common pain is chaffing. It occurs when one’s upper thighs rub together

A group of runners in Central Park, New York City.

Upright posture and a slight forward lean
Leaning forward places a runner’s center of mass on the front part of the foot, which avoids landing on the heel and facilitates the use of the spring mechanism of the foot. It also makes it easier for the runner to avoid landing the foot in front of the center of mass and the resultant braking effect. While upright posture is essential, a runner should maintain a relaxed frame and use his/her core to keep posture upright and stable. This helps prevent injury as long as the body is neither rigid or tense. When leaning forward, focus on leaning only slightly from the waist and the rest of the body will naturally follow. The most common running mistakes are tilting the chin up and scrunching shoulders.

Stride rate and Types
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

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and makes the skin raw. The skin feels coarse and has a rash-like look. It can be prevented by either rubbing petroleum jelly, deodorant, or special anti-chafing creams (sold in sticks that look like deodorant) to the area of the skin that rubs together. A cold bath is a popular treatment of subacute injuries or inflammation, muscular strains, and overall muscular soreness, but which efficacy is controversial.[8] Some claim that for runners in particular, ice baths offer two distinct improvements over traditional techniques. First, immersion allows controlled, even constriction around all muscles, effectively closing microscopic damage that cannot be felt and numbing the pain that can. One may step into the tub to relieve sore calves, but quads, hams, and connective tissues from hips to toes will gain the same benefits, making hydrotherapy an attractive preventive regimen. Saint Andrew’s crosscountry coach John O’Connell, a 2:48 masters marathoner, will hit the ice baths before the ibuprofen. "Pain relievers can disguise injury," he warns. "Ice baths treat both injury and soreness." The second advantage involves a physiological reaction provoked by the large amount of muscle submerged. Assuming one has overcome the mind’s initial flight response in those first torturous minutes, the body fights back by invoking a "blood rush". This rapid transmission circulation flushes the damage-inflicting waste from the system, while the cold water on the outside preserves contraction. Like an oil change or a fluid dump, the blood rush revitalizes the very areas that demand fresh nutrients. Make sure not to stay in longer than 15 minutes, with 10 minutes usually being sufficient. Some claim that all of those can be effective in both minimizing and recovering from running injuries. One major problem of many runners is that they run on concrete. The problem with running on concrete is that the body adjusts to this flat surface running and some of the muscles will become weaker. Concrete is also a hard surface and the stress it produces on the knee is problematic. It is advised 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.

Running
Reducing the frequency and duration can also prevent injury, three 20-30 minute sessions a week should suffice. A runner who finds himself injured should not continue to run because continuing could further damage the injury and prolong the recovery. A common acronym used to help the recovery process is RICE: Rest, Ice, Compression, and Elevation. Another injury prevention method common in the running community is stretching. Stretching is often recommended as a requirement to avoid running injuries, and it is almost uniformly performed by competitive runners of any level. Recent medical literature, however, finds mixed effects of stretching prior to running. One study found insufficient evidence to support the claim that stretching prior to running was effective in injury prevention or soreness reduction.[9] Another, however, has demonstrated that stretching prior to running increases injuries, while stretching afterwards actually decreases them.[10] The American College of Sports Medicine recommends that all stretching be done after exercise because this is when the muscles are most warmed up and capable of increasing flexibility. Recent studies have also shown that stretching will reduce the amount of strength the muscle can produce during that training session. Inconsistent experimental methodology and the failure to use proper stretching methods are reasons given to explain the conflicting results. Because of this, members of the running community argue that stretching remains helpful. In recent years, further studies and evidence has shown that barefoot running reduces running related injuries. "Some experts now believe that most athletic shoes, with their inflexible soles, structured sides and super-cushioned inserts keep feet so restricted that they may actually be making feet lazy, weak and more prone to injury. As a result, barefoot training is gaining more attention among coaches, personal trainers and runners."[11] "Research has shown that wearing shoes to exercise takes more energy, and that barefoot runners use about 4 percent less oxygen than shoe runners. Other studies suggest barefoot athletes naturally compensate for the lack of cushioning and land more softly than runners in shoes, putting less shock and strain on the rest of the body. Barefoot runners also tend to land in the

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middle of their foot, which can improve running form and reduce injury."[11] Barefoot running is becoming a larger and more vocal community, as the benefits of unshod running become more visible and measurable. Additionally, there have been claims that improved posture reduces injuries and helps to cope with existing injuries.[12] Some believe that running may increase osteoarthritis of the knee, due to stress causing lesions on the cartilage which become irreversible with time. Recent studies, however, have shown that runners do not have more osteoarthritis than people who do not run. Although it is not an injury, people with asthma suffer sometimes from running, especially if they have exercise-induced asthma. Asthma becomes more a problem with colder weather, increased speed, and uphills.

Running
hormone in response to prolonged participation in the sport. In fact, running is the usual recommended therapy to treat people with clinical depression and people coping with addiction. Sometimes, runners may even become "addicted" to running itself.[15] In animal models, running has been shown to increase the number of newly born neurons within the brain.[16] This finding could have significant implications in aging as well as learning and memory.

Running as a sport
Running is both a competition and a type of training for sports which 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 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 a key part of the ancient Olympic Games as well as the modern Olympics. Today, road racing is a popular sport among non-professional athletes, who included over 7.7 million people in America alone in 2002. [17]

Benefits of running
While there is the potential for injury in running (just as there is in any sport), there are many benefits. Some of these benefits include potential weight loss, improved cardiovascular health, increased muscle mass, increased bone density, and an improved emotional state. Following a consistent routine of running can increase HDL levels, reducing the risks of cardiovascular disease. Running, like all forms of regular exercise, can effectively slow[13] or reverse[14] the effects of aging. Running can assist people in losing weight and staying in shape. 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 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 the sport report feeling an elated, euphoric state, often referred to as a “runner’s high”. It has been suggested that hormones known as endorphins are the modulators of this effect, as the body is known to produce and release the

Types of running events
• • • • • • • • Track running Road running Cross country running Trail running Fell running Relay Race Recreational running Talus Running (running across the rock debris at the bottom of mountains)

Classification of running by distance
• • • • Sprints Middle distance Long distance Marathon

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• Ultrarunning • Multiday running

Running
[9] Herbert, R.D. & Gabriel, M. (2002). Effects of stretching before and after exercising on muscle soreness and risk of injury: systematic review. British Medical Journal, 325 p. 468. online [10] Stretching and running injuries [11] ^ Tara Parker-Pope, The Wall Street Journal [12] The Egoscue Method of Health through Motion, Pete Egoscue and Roger Gittins [13] Exercise Could Slow Aging Of Body, Study Suggests [14] Exercise ’can reverse ageing’ [15] "Health benefits of running", Free Diets, http://www.freediets.com/endurancetraining/the-benefits-of-running. [16] van Praag H, Kempermann G, Gage FH (March 1999), "Running increases cell proliferation and neurogenesis in the adult mouse dentate gyrus", Nat. Neurosci. 2 (3): 266–70, doi:10.1038/ 6368, PMID 10195220. [17] USA Track & Field (2003). "Long Distance Running - State of the Sport."

See also
• • • • • • • Athletic training Largest Footraces Great North Run Jim Fixx Jogging Marathon Persistence hunting • • • • • • Olympic Games Orienteering Triathlon Road running Ted Corbitt Barefoot running

References
[1] Hall, C., Figueroa, A, Fernhall, B & Kanaley, J.A. (2004) Energy expenditure of walking and running: Comparison with prediction equations. Medicine & Science in Sport & Exercise, 36 (12), 2128-2134. Abstract [2] Hoffman, K. (1971), "Stature, leg length and stride frequency", Track Technique 46: 1463–69. [3] Rompottie, K. (1972), "A study of stride length in running", International Track and Field: 249–56. [4] Pacing chart for running [5] The painful truth about trainers: Are running shoes a waste of money? [6] Superglue for Blisters, Cuts and First Aid [7] Medical Tape Nipple Saver [8] After Exercise - Does an Ice Water Bath Speed Recovery?

External links
• Running at the Open Directory Project • Statistics on the maximum speeds humans can currently run • • Media related to Running at Wikimedia Commons "running", Encyclopædia Britannica (11th ed.), 1911.

Retrieved from "http://en.wikipedia.org/wiki/Running" Categories: Endurance sports, Human skills, Running, Locomotion This page was last modified on 22 May 2009, at 13:47 (UTC). All text is available under the terms of the GNU Free Documentation License. (See Copyrights for details.) Wikipedia® is a registered trademark of the Wikimedia Foundation, Inc., a U.S. registered 501(c)(3) taxdeductible nonprofit charity. Privacy policy About Wikipedia Disclaimers

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