Tuesday, November 30, 2010

Netball

History Of Netball


    * Netball is a ball sport played between two teams of seven players. The sport shares many similarities with basketball, having been derived from early versions of women's basketball. It developed as a distinct sport in the 1890s in England, from where it spread to other countries. Netball is popular in Commonwealth nations and is predominantly played by women.

    * Games are played on a rectangular court divided into thirds, with a raised goal at each short end. The object of the game is for teams to score goals, by passing a ball and shooting it into the opposing team's goal. Players are assigned "positions" that define their role within the team and restrict their movement on court. During general play, a player with the ball can take no more than one step before passing it, and must pass the ball or shoot for goal within three seconds. Goals can only be scored by the assigned shooting players. Netball games are 60 minutes long, divided into 15-minute quarters, at the end of which the team with the most goals scored wins.


Court and its dimensions

    * Like basketball, netball is played on either a hard or soft court with scoring hoops or "rings" at both ends. The court is slightly larger than a basketball court, being 30.5 m long and 15.25 m wide. The longer sides are called "side lines" and the shorter sides are called "goal lines"or "back lines". Court markings are no more than 50 mm wide. The court is divided into thirds which regulate where individuals of each position are allowed to move. A 90 cm-diameter "centre circle" is located in the centre of the court. At each end of the court there is a 4.9 m-radius semi-circular "shooting circle" or "goal circle" from within which all scoring shots must be taken. The goal posts are 3.05 m high from the top of the ring to the ground and have no backboards. The rings have an internal diameter of 380 mm and are located 150 mm forward from the post and are made of 15 mm diameter steel. The height is the same as a basketball hoop, but in netball the diameter of the rings is 3 inches smaller. It is possible to play netball using a basketball hoop but if there is any contact between the ball and the backboard, the ball is considered out of play. If a goal is scored off the backboard it does not count. Some versions of the rules allow a goal to be scored from a backboard rebound if a player who can catch the ball throws the ball in without touching the ground.

Scoring goals


    * By the combination of the above, only the Goal Attack and Goal Shooter are able to score goals directly, and this may only be done from the inside of the circle. The job of the Goal Defence and Goal Keeper is to block the Goal Attack and Goal Shooter from shooting; however, they must be three feet or more away from the landing foot of the shooter, otherwise it is called an obstruction. In this, the Goal Keeper or Goal Defence must stand by the shooter's side for a penalty pass or shot and are now not allowed to block. A ball that passes through the hoop, but has been thrown either from outside the circle or by a player not the GA or GS, is deemed a "no goal". Furthermore, a shooter (GA or GS) may not shoot for a goal if a "free pass" has been awarded for an infringement such as stepping, offside, or using the post.

    * If a player misses and the ball does not touch the rim or any part of the post, the player cannot catch it otherwise it is called replay. This results in a free pass to the other team.


Starting and restarting play

    * At the beginning of every quarter or after a goal is scored, play starts from the centre of the court with a "centre pass". These passes alternate between the teams, regardless of which team scored the last goal. A centre pass is made by a player in the "centre" position who must have one foot grounded within the centre circle. As the game restarts, only the player in the 'Centre' position from each team are allowed in the centre third of the court. When the umpire blows the whistle to restart play, players in the positions "Goal Attack", "Goal Defence", "Wing Attack" and "Wing Defence" can move into the centre third, where the centre pass must be caught.

    * If the ball touches the ground outside the court boundaries, then a member of the team that was not the last to touch the ball before it went out is able to throw the ball back into the court to restart play.

Stepping, footwork, and passing


    * Netball rules do not permit players to let their landing foot touch the ground again if it is lifted at all while in possession of the ball, so players can take 1.5 steps while holding the ball. Players are entitled to balance on the other foot if the landing foot is lifted. Consequently, the only way to move the ball towards the goal is to throw the ball to a team-mate. The ball can be held by a player for less than three seconds at any time. A player may tap (deflect) the ball let it bounce and then take possession and throw it. The player cannot catch the ball (with both hands), drop it and pick it up again; this is called a replayed ball. The duration before it is called a drop is determined by the umpire. These rules, combined with the restrictions on where one player of a particular position can move, ensure that everyone on the team is regularly involved in play.


Contact and obstruction


    * Contact is only permitted provided it does not impede with an opponent or the general play and players must be at least three feet (90 centimetres) away from a player with the ball while attempting to defend. If impeding contact is made, a penalty is given to the team of the player who was contacted, and the player who contacted must stand "out of play", meaning they cannot participate in play until the player taking the penalty has passed the ball.


Playing time

    * A game is played in four quarters, each one lasting fifteen minutes, with intervals of three minutes between the first and second quarters, and between the third and fourth quarters. There is also an interval of five minutes at half time. If a player/umpire calls time, and the time keeper pauses the timer. When the game starts and the player has swapped places with another player, or is healthy, play is resumed and the timer is restarted.

Cycling

History of cycling

    * Bicycles were introduced in the 19th century and now number about one billion worldwide.[4] They are the principal means of transportation in many regions.

    * Cycling is an extremely efficient mode of transportation[5] optimal for short to moderate distances. Bicycles provide numerous benefits compared to motor vehicles, including exercise, an alternative to the use of fossil fuels, no air or noise pollution, much reduced traffic congestion and likelihood of causing a fatality, easier parking, greater maneuverability, and access to both roads and paths. The advantages are at less financial cost to the user as well as society (negligible damage to roads, and less pavement required).[6] Criticisms and disadvantages of cycling include reduced protection in crashes, particularly with motor vehicles,[7] longer travel time (except in densely populated areas), vulnerability to weather conditions, difficulty in transporting passengers, and the skill and fitness required.


Types
Urban


    * Cyclists, pedestrians and motorists make different demands on road design which may lead to conflicts. Some jurisdictions give priority to motorized traffic, for example setting up one-way street systems, free-right turns, high capacity roundabouts, and slip roads. Others may apply traffic restraint measures to limit the impact of motorized transport. In the former cases, cycling has tended to decline while in the latter it has tended to be maintained. Occasionally, extreme measures against cycling may occur. In Shanghai, where bicycles were once the dominant mode of transport, bicycle travel on a few city roads was banned temporarily in December 2003.

    * In areas in which cycling is popular and encouraged, cycle-parking facilities using bicycle stands, lockable mini-garages, and patrolled cycle parks are used in order to reduce theft. Local governments promote cycling by permitting the carriage of bicycles on public transport or by providing external attachment devices on public transport vehicles. Conversely, an absence of secure cycle-parking is a recurring complaint by cyclists from cities with low modal share of cycling

Utility

    * Utility cycling refers both to cycling as a mode of daily commuting transport as well as the use of a bicycle in a commercial activity, mainly to transport goods.

    * The postal services of many countries have long relied on bicycles. The British Royal Mail first started using bicycles in 1880; now bicycle delivery fleets include 37,000 in the UK, 25,700 in Germany, 10,500 in Hungary and 7000 in Sweden. The London Ambulance Service has recently introduced bicycling paramedics, who can often get to the scene of an incident in Central London more quickly than a motorized ambulance.

    * Late in the 20th century, urban police bicycles became more common, as the mobility of car-borne officers was increasingly limited by traffic congestion and pedestrianisation.


Recreational

Bicycle Touring

    * Bicycles are used for recreation at all ages. Bicycle touring, also known as cyclotourism, involves touring and exploration or sightseeing by bicycle for leisure. A brevet or randonnĂ©e is an organized long-distance ride.

    * One popular Dutch pleasure is the enjoyment of relaxed cycling in the countryside of the Netherlands. The land is very flat and full of public bicycle trails where cyclists aren't bothered by cars and other traffic, which makes it ideal for cycling recreation. Many Dutch people subscribe every year to an event called fietsvierdaagse — four days of organised cycling through the local environment. Paris–Brest–Paris (PBP), which began in 1891, is the oldest bicycling event still run on a regular basis on the open road, covers over 1,200 km (746 mi) and imposes a 90-hour time limit. Similar if smaller institutions exist in many countries.


Mountain


    * Mountain biking grew in the late 20th century, including recreation and racing. Most mountain biking takes place on dirt roads, trails and in purpose-built parks. Downhill mountain biking has just evolved in the recent years and is performed at places such as Whistler Mountain Bike Park. Slopestyle, a form of downhill, is when riders do tricks such as tailwhips, 360s, backflips and frontflips.


Associations

    * Cyclists form associations, both for specific interests (trails development, road maintenance, urban design, racing clubs, touring clubs, etc.) and for more global goals (energy conservation, pollution reduction, promotion of fitness). Some bicycle clubs and national associations became prominent advocates for improvements to roads and highways. In the United States, the League of American Wheelmen lobbied for the improvement of roads in the last part of the 19th century, founding and leading the national Good Roads Movement. Their model for political organization, as well as the paved roads for which they argued, facilitated the growth of the automobile.

    * As a sport, cycling is governed internationally by the Union Cycliste Internationale in Switzerland, USA Cycling (merged with the United States Cycling Federation in 1995) in the United States, (for upright bicycles) and by the International Human Powered Vehicle Association (for other HPVs, or human-powered vehicles). Cycling for transport and touring is promoted on a European level by the European Cyclists' Federation, with associated members from Great Britain, Japan and elsewhere.

Diving


History of Diving

    * Diving is the sport of jumping or falling into water from a platform or springboard, sometimes while performing acrobatics. Diving is an internationally-recognized sport that is part of the Olympic Games. In addition, unstructured and non-competitive diving is a recreational pastime.

    * Diving is one of the most popular Olympic sports with spectators. Competitors possess many of the same characteristics as gymnasts and dancers, including strength, flexibility, kinaesthetic judgment and air awareness.

    * China came to prominence several decades ago when the sport was revolutionized by national coach Liang Boxi and after intense study of the dominant Louganis. China has lost few world titles since. The success of Greg Louganis has led to American strength in diving internationally. Other noted countries in the sport include Italy, Australia and Canada.



Competitive springboard diving


Arvid SpÄngberg (1908 Summer Olympics)

    * A man dives into the Great South Bay of Long Island

    * Most diving competitions consist of three disciplines: 1m and 3m springboards, and the platform. Competitive athletes are divided by gender, and often by age group. In platform events, competitors are allowed to perform their dives on either the five, seven and a half (generally just called seven) or ten meter towers. In major diving meets, including the Olympic Games and the World Championships, platform diving is from the 10 meter height.

    * Divers have to perform a set number of dives according to established requirements, including somersaults and twists. Divers are judged on whether and how well they completed all aspects of the dive, the conformance of their body to the requirements of the dive, and the amount of splash created by their entry to the water. A possible score out of ten is broken down into three points for the takeoff, three for the flight, and three for the entry, with one more available to give the judges flexibility.


Synchronized diving

    * Synchronized diving was adopted as an Olympic sport in 2000. Two divers form a team and perform dives simultaneously. The dives are usually identical; however, sometimes the dives may be opposites, in what is called a pinwheel. In these events, the diving is judged both on the quality of execution and the synchronicity - in timing of take-off and entry, height and forward travel.


Scoring the dive

There are rules governing the scoring of a dive. Usually a score considers three elements of the dive: the approach, the flight, and the entry. The primary factors affecting the scoring are:

the platform selected (10 meter, 7.5 meter, or 5 meter)


   1. if a hand-stand is required, the length of time and quality of the hold
   2. the height of the diver at the apex of the dive, with extra height resulting in a higher score
   3. the distance of the diver from the diving apparatus throughout the dive (a diver must not be dangerously close, should not be too far away, but should ideally be within 2 feet (0.61 m) of the platform)
   4. the properly defined body position of the diver according to the dive being performed, including pointed toes and feet touching at all times
   5. the proper amounts of rotation and revolution upon completion of the dive and entry into the water
   6. angle of entry - a diver should enter the water straight, without any angle. Many judges award divers for the amount of splash created by the diver on entry, with less splash resulting in a higher score.


Competitive strategy
    * To win dive meets, divers create a dive list in advance of the meet. To win the meet the diver must accumulate more points than other divers. Often, simple dives with low DDs will look good to spectators but will not win meets. The competitive diver will attempt the highest DD dives possible with which they can achieve consistent, high scores. If divers are scoring 8 or 9 on most dives, it may be a sign of their extreme skill, or it may be a sign that their dive list is not competitive, and they may lose the meet to a diver with higher DDs and lower scores.

    * In competition, divers must submit their lists beforehand, and once past a deadline (usually when the event is announced or shortly before it begins) they cannot change their dives. If they fail to perform the dive announced, even if they physically cannot execute the dive announced or if they perform a more difficult dive, they will receive a score of zero. Under exceptional circumstances, a redive may be granted, but these are exceedingly rare (usually for very young divers just learning how to compete, or if some event outside the diver's control has caused them to be unable to perform).


Governance

    * The global governing body of diving is FINA, which also governs swimming, synchronized swimming, water polo and open water swimming. Almost invariably, at national level, diving shares a governing body with the other aquatic sports.

    * This is frequently a source of political friction as the committees are naturally dominated by swimming officials who do not necessarily share or understand the concerns of the diving community. Divers often feel, for example, that they do not get adequate support over issues like the provision of facilities. Other areas of concern are the selection of personnel for the specialised Diving committees and for coaching and officiating at events, and the team selection for international competitions.


Mechanics of diving

    * Tomb of the Diver, Paestum, Italy, a Greek fresco dated 470 BC

    * At the moment of take-off, two critical aspects of the dive are determined, and cannot subsequently be altered during the execution. One is the trajectory of the dive, and the other is the magnitude of the angular momentum.

    * The speed of rotation - and therefore the total amount of rotation - may be varied from moment to moment by changing the shape of the body, in accordance with the law of conservation of angular momentum.

    * The center of mass of the diver follows a parabolic path in free-fall under the influence of gravity (ignoring the effects of air resistance, which are negligible at the speeds involved).


Trajectory

    * Since the parabola is symmetrical, the travel away from the board as the diver passes it is twice the amount of the forward travel at the peak of the flight. Excessive forward distance to the entry point is penalized when scoring a dive, but obviously an adequate clearance from the diving board is essential on safety grounds.

    * The greatest possible height that can be achieved is desirable for several reasons:

    * the height attained is itself one of the factors that the judges will reward.

    * a greater height gives a longer flight time and therefore more time to execute maneuvers.

    * for any given clearance when passing the board, the forward travel distance to the entry point will be less for a higher trajectory.