Track events

In terrestrial animals, the primary propulsive organ is the legs, though a few species use their tails. Typical characteristics of jumping species include long legs, large leg muscles, and additional limb elements. Long legs benefit by increasing the time and distance over which the animal can push against the substrate, thus allowing more power and faster, farther jumps. Large leg muscles can generate greater forces, resulting in improved jumping performances. Many jumping animals have not only elongated the normal leg elements, but have also elongated other parts of the limb, such as foot and ankle bones, effectively adding more segments to the limb and even more length. Frogs are an excellent example of all three trends: frog legs can be nearly twice the body length, leg muscles may account for up to 20% of body weight, and they have not only lengthened the foot, shin and thigh, but extended the ankle bones into another limb joint and similarly extended the hip bones and gained mobility at the sacrum for a second 'extra joint'. As a result, frogs are the undisputed champion jumpers of vertebrates, leaping over 50 body lengths, more than 8 feet.

Grasshoppers are known to use elastic energy storage in order to increase jumping distance. As noted above, power output is the strongest determinant of jump distance, but the power that muscles can generate is limited due to physiological constraints of the muscles themselves to approximately 300 Watts per kg of muscle. In order to circumvent this power limitation, grasshopers anchor their legs via an internal 'catch mechanism' while their muscles stretch an elastic apodeme (similar to a vertebrate tendon). When the catch is released, the apodeme releases its energy all at once, at a much higher power output than muscles are capable of. This would be analogous to a human throwing an arrow by hand versus using a bow - the use of elastic storage allows muscles to operate c

Physics of jumping

A split leap executed by an acro dancer. This is one of several types of leaps found in dance.

All jumping is governed by basic physical laws of ballistic trajectories - once the animal has completely launched itself from the substrate, it will traverse a parabolic path determined by the launch angle, with launch angle and initial launch velocity determining distance, duration, and height of the jump. Maximum jump distance occurs at a launch angle of 45 degrees, but an animal can be within a range of 35-55 degrees and still achieve 90% of maximal distance.

A jump can be initiated when the animal is either moving or stationary. In a jump from stationary (a 'standing jump'), the animal is initially stationary, and all of the work done to accelerate the body through launch until takeoff is achieved is done in a single movement. The muscles do a certain amount of physical work (adding kinetic energy to the system), resulting in the final kinetic energy of the body (which is proportional to velocity squared). The more work the muscles do, the greater the final speed, thus the shorter the time interval of the jump's propulsive phase. Work divided by time = power. The more power generated, the greater the jump distance or height will be. Many jumping animals have muscles optimized for power production (as opposed to optimization for force or velocity), as well as adaptations such as elastic elements to increase power output.

In a moving jump or 'running jump', the animal simply redirects its velocity, attempting to conserve as much momentum as possible to add to the jump distance. Because the total kinetic energy of the jumping animal is not solely due to the jump movement itself, as is the case in a standing jump, but rather the energy of the jump plus the prior energy of the body, animals can often jump farther and higher if they 'get a running start'. In some cases, the animal will simply move in a give direction until they lose contact with it, without any specific launch movements, such as when a person runs across a gap from an elevated launch area, or when a dolphin swims upwards until breaking the surface at a given angle and velocity.

Jumping requires applying force against a substrate, which will in turn generate a reactive force, propelling the animal into the launch. This can be accomplished by pushing off against the ground or the water. In the latter case, dolphins often display moving jumps, while Indian skitter frogs can execute a standing jump from water. Jumping is typically defined by an airborne phase after launch from a substrate with a path defined by ballistic formulae, so animals cannot 'jump' underwater, as the drag and buoyancy overwhelm the influence of gravity. Similarly, while a bird can jump into the air in order to initiate flight, no movement it performs once airborne can be considered 'jumping'.

Inside the track

Annually, from 1796-1798, L'Olympiade de la République was held in revolutionary France, and is an early forerunner to the modern summer Olympic Games. The premier event of this competition was a footrace, but various ancient Greek disciplines were also on display. The 1796 Olympiade also marks the introduction of the metric system into sport.In the 19th century the formal organization of the modern events accelerated - in France, Germany, and Great Britain in particular. This included the incorporation of regular sports and exercise into school regimes. The Royal Military College, Sandhurst has claimed to be the first to adopt this in 1812 and 1825, but without any supporting evidence. The earliest recorded meeting was organised at ewsbury, Shropshire in 1840 by the Royal Shrewsbury School Hunt. There are details of the meeting in a series of letters written 60 years later by C.T. Robinson, who was a pupil there from 1838 to 1841. The Royal Military Academy at Woolwich held an organised competition in 1849, but the first egular series of meetings was held by Exeter College, Oxford from 1850.Modern athletic events are usually organized around a 400 metre running track on which most of the running events take place. Field events (vaulting, jumping, and throwing) often take place on the infield, inside the track.

Modern Olympic Games in

Athletics was included in the first modern Olympic Games in 1896 and has formed their backbone ever since. Women were first allowed to participate in track and field events in the 1928 Olympics.An international governing body, the International Amateur Athletics Federation (IAAF), was founded in 1912; it adopted its current name, the International Association of Athletics Federations, in 2001. The IAAF established separate outdoor World Championships in 1983. There are a number of regional games as well, such as the European Championships, the Pan-American Games, and the Commonwealth Games. In addition there is a professional Golden League circuit, cumulating in the IAAF World Athletics Final, and indoor championships such as the World Indoor Championships. The sport has a very high profile during major championships, especially the Olympics, but otherwise is less popular.The AAU (Amateur Athletic Union) was the governing body in the United States until it collapsed under pressure from advancing professionalism in the late 1970s. A new governing body called The Athletics Congress (TAC) was formed. It was later renamed USA Track & Field (USATF or USA T&F). An additional, less structured organization, the Road Runners Club of America (RRCA), also exists in the United States to promote road racing.In modern times, athletes can receive money for racing, putting an end to the so-called "amateurism" that existed before.

Indoor tracks,

There are two seasons for track and field. There is an indoor season, run during the winter and an outdoor season, run during the spring. Most indoor tracks are 200 metres and consist of four to 8 lanes. There are also some 150 metre indoor tracks, and others as small as 120 metres have been used. Some "oversize tracks" (larger than 200 metres) are popular for American collegiate athletics despite the fact that they are not considered valid for setting indoor records. Often an indoor track will have banked turns to compensate for the tight radius of the turns. The banking can help prevent injuries to the athlete, while also promoting higher speeds. In an indoor track meet athletes contest the same track events as at an outdoor meet, with the exception of the 100 m and 110 m/100 m hurdles (replaced by the 55 or 60 m sprint and 55 or 60 m hurdles at most levels, or the 55 m sprint and hurdles at the high school level), the 10,000 m run, 3,000 m steeplechase, 400 m hurdles. Indoor meets also have the addition of a 3,000 m run normally at both the collegiate and elite level, instead of the 10,000 m. The 5,000 m is the longest event commonly run indoors, although there are situations where longer distances have been raced. In the mid 20th century, there was a series of "duel" races on Madison Square Garden's indoor track, some of which featured two men racing a marathon (42.2 km). However, this is an extremely rare occurrence, for obvious reasons. In some occasions, there may also be a 500 m race instead of the open 400 m normally found outdoors, and in many college championship races indoors both are contested.In field events, indoor meets only feature the high jump, pole vault, long jump, triple jump, and shot put (weight throw). Due to space limitations, these events take place on the infield, within the circumferential track. The longer throws of javelin, hammer and discus are added only for outdoor meets, as there is normally not enough space in an indoor stadium to house these events.

Outdoor athletics

Other events unique to indoor meets (especially in North America) are the 300 m, 600m, 1000 m, and 35 lb (16 kg) weight throw. In some countries, notably Norway, standing long jump and standing high jump are also contested, even in the National Championships. For multi-event athletes there is the Pentathlon for women (consisting of 60 m hurdles, high jump, shot put, long jump and 800 m) and heptathlon for men (consisting of 60 m, long jump, shot put, high jump, 60 m hurdles, pole vault and 1000 m) indoors. The outdoor track and field season usually begins in the spring and lasts through the summer. Most tracks are ovals of 400 metres in circumference. Modern "tartan tracks" or more recently "mondo tracks" are made with a rubberized surface; older tracks were cinder-covered. Tracks normally consist of 6-10 lanes (up to 12 lanes on the 'front' straight) and many include a steeplechase lane with a water pit on one of the turns. This steeplechase pit can be placed either inside or outside the track, making for a tighter turn or a wider turn. It is common that tracks will surround a playing field used for American football, football (soccer), or lacrosse. This inner field is usually known as the infield and has a surface of either grass or artificial turf.All field events can be contested on the infield. However the javelin, hammer and discus throws are sometimes contested on fields outside of the track stadium because they take up a large amount of space, the implements may damage the infield, and the implements could end up landing on the track. However, some infields are used specifically for these events, and for the javelin, an athlete may have a longer run-up by starting it on the other side of the track, and crossing when there are no athletes passing.

Events

All field events can be contested on the infield. However the javelin, hammer and discus throws are sometimes contested on fields outside of the track stadium because they take up a large amount of space, the implements may damage the infield, and the implements could end up landing on the track. However, some infields are used specifically for these events, and for the javelin, an athlete may have a longer run-up by starting it on the other side of the track, and crossing when there are no athletes passing. There are other variations besides the ones listed below, but races of unusual length (e.g. 300 m) are run much less often. The unusual races are typically held during indoor season because of the shorter 200 m indoor track. With the exception of the mile run, races based on imperial distances are rarely run on the track anymore since most tracks have been converted from a quarter mile (402.3 m) to 400 m; almost all record keeping for imperial distances has been discontinued. However, the IAAF record book still includes the mile world record (currently held by Hicham El Guerrouj of Morocco for men and Svetlana Masterkova of Russia for women) because of its worldwide historic significance.Men and women do not compete against each other, although they may sometimes run in the same races due to time constraints at high school meets. Women generally run the same distances as men although hurdles and steeplechase barriers are lower and the weights of the shot, discus, javelin and hammer are less.