Editing Javelin throw (section)

==Rules and competitions==
{{More citations needed section|date=March 2022}}

The size, shape, minimum weight, and center of gravity of the javelin are all defined by [[World Athletics]] rules. In international competition, men throw a javelin between {{convert|2.6|and|2.7|m|abbr=on}} in length and {{convert|800|g|abbr=on}} in weight, and women throw a javelin between {{convert|2.2|and|2.3|m|abbr=on}} in length and {{convert|600|g|abbr=on}} in weight. The javelin has a grip, about {{convert|150|mm|abbr=on}} wide, made of cord and located at the javelin's center of gravity ({{convert|0.9|to|1.06|m|abbr=on}}) from the javelin tip for the men's javelin and {{convert|0.8|to|0.92|m|abbr=on}} from the javelin tip for the women's javelin.

[[File:Matti Järvinen.jpg|thumb|left|180px|[[Matti Järvinen (javelin)|Matti Järvinen]] throwing the javelin at the 1932 Olympics]]

Unlike the other throwing events ([[shot put]], [[discus]], and [[Hammer throw|hammer]]), the technique used to throw the javelin is dictated by World Athletics rules and "non-orthodox" techniques are not permitted. The javelin must be held at its grip and thrown overhand, over the athlete's shoulder or upper arm. Further, the athlete is prohibited from turning completely around or starting with their back facing the direction of the throw. This prevents athletes from attempting to spin and hurl the javelin sidearm in the style of a [[discus throw]]. This rule was put in place when a group of athletes began experimenting with a spin technique referred to as "free style". On 24 October 1956, [[Pentti Saarikoski (athlete)|Pentti Saarikoski]] threw {{T&Fcalc|99.52}}<ref>Pentti Saarikosk</ref> using the technique holding the end of the javelin. Officials were so afraid of the out of control nature of the technique that the practice was banned through these rule specifications.

Instead of being confined to a circle, javelin throwers have a runway {{convert|4|m|abbr=on}} wide and at least {{convert|30|m|abbr=on}} in length, ending in an {{cvt|8|m}} radius ''throwing arc'' from which their throw is measured; athletes typically use this distance to gain momentum in a "run-up" to their throw. Like the other throwing events, the competitor may not leave the throwing area (the runway) until after the implement lands. The need to come to a stop behind the throwing arc limits both how close the athlete can come to the line before the release as well as the maximum speed achieved at the time of release.

The javelin is thrown towards a 28.96º [[circular sector]] that is centered on the center point of the throwing arc. The angle of the throwing sector (28.96º) provides sector boundaries that are easy to construct and lay out on a field.<ref>{{cite web |url=http://www.pntf.org/officials/ivars/Throwing_Event_Sector_Angles_Rev_F1.pdf |title=Laying Out Sector Angles for the Track and Field Throwing Events |author=<!--Not stated--> |access-date=2022-03-19 |website=USA Track & Field Pacific Northwest}}</ref> A throw is only legal if the tip of the javelin lands within this sector and first strikes the ground before any other part of the javelin.<ref>{{Cite web|title=Javelin Throw|url=https://www.worldathletics.org/disciplines/throws/javelin-throw|access-date=2021-01-22|website=worldathletics.org|language=en}}</ref> The distance of the throw is measured from the throwing arc to the point where the tip of the javelin landed, rounded down to the nearest centimetre.

Competition rules are similar to other throwing events: a ''round'' consists of one attempt by each competitor in turn, and competitions typically consist of three to six rounds. The competitor with the longest single legal throw (over all rounds) is the winner; in case of a tie, the competitors' second-longest throws are also considered. Competitions involving large numbers of athletes sometimes use a ''cut'' whereby all competitors compete in the first three rounds but only those who are currently among the top eight or have achieved some minimum distances are permitted to attempt to improve on their distance in additional rounds (typically three).

The javelin is almost always thrown outdoors, though it is rarely thrown [[indoor track|indoors]]. The world record for men's indoor javelin throw is 85.78 metres by [[Matti Närhi]] in 1996.<ref>{{Cite web |title=Undercover javelin {{!}} SPIKES {{!}} World Athletics |url=https://worldathletics.org/spikes/news/finland-indoor-javelin |access-date=2024-05-17 |website=worldathletics.org}}</ref>

===Javelin redesigns===
{{see also|Timeline of changes in the sport of athletics}}
[[File:Bundesarchiv Bild 183-1984-0513-018, Uwe Hohn.jpg|thumb|[[Uwe Hohn]] (pictured in 1984) holds the "eternal world record" with a throw of 104.80&nbsp;m, as a new type of javelin (less debate of landing spot, less danger of reaching the spectators) was implemented in 1986.]]
On 1 April 1986, the men's javelin ({{convert|800|g|lbs|sigfig=3|lk=on}}) was redesigned by the governing body (the [[IAAF]] Technical Committee). They decided to change the rules for javelin design because of the increasingly frequent flat landings and the resulting discussions and protests when these attempts were declared valid or invalid by competition judges. The world record had also crept up to a potentially dangerous level, {{convert|104.80|m|abbr=on}} by [[Uwe Hohn]]. With throws exceeding 100 metres, it was becoming difficult to safely stage the competition within the confines of a stadium infield. The javelin was redesigned so that the [[centre of gravity]] was moved {{convert|4|cm|abbr=on}} forward. In addition, the surface area in front of centre of gravity was reduced, while the surface area behind the centre of gravity was increased. This had an effect similar to that produced by the feathers on an arrow. The javelin turns into the [[relative wind]]. This relative wind appears to originate from the ground as the javelin descends, thus the javelin turns to face the ground. As the javelin turns into the wind less lift is generated, reducing the flight distance by around 10% but also causing the javelin to stick in the ground more consistently. In 1999, the women's javelin ({{convert|600|g|lbs|sigfig=3}}) was similarly redesigned.<ref>{{cite web|url=http://www.worldofjavelin.com/posts/physics-javelin-designs-whats-the-significance/|title=Physics: Javelin Designs, what's the significance? – World of Javelin|work=worldofjavelin.com|access-date=27 March 2012|archive-url=https://web.archive.org/web/20150402160908/http://www.worldofjavelin.com/posts/physics-javelin-designs-whats-the-significance/|archive-date=2 April 2015|url-status=dead}}</ref>

Modifications that manufacturers made to recover some of the lost distance, by increasing tail drag (using holes, rough paint or dimples), were forbidden at the end of 1991 and performances made using implements with such modifications removed from the record books. [[Seppo Räty]] had achieved a world record of {{convert|96.96|m|abbr=on}} in 1991 with such a design, but this record was nullified.

===Weight rules by age group===
The weight of the javelin in the [[Under-20 athletics|Under-20]] category is the same as the [[Open class (track and field)|senior]] level.<ref>{{cite web|url=https://www.athleticsdirect.co.uk/throwing-weight-rules-1/|title=Throwing Weight Rules per Age Group|date=7 July 2016|publisher=athleticsdirect.co.uk|access-date=10 July 2018}}</ref>
{| class="wikitable" width=40% style="font-size:90%; text-align:center;"
|-
| || colspan=1 bgcolor=lightblue|'''Men''' ||colspan=2 bgcolor=pink|'''Women'''
|-
|'''Age group''' || '''Weight''' || '''Weight'''
|-
|U14|| colspan="2"| {{cvt|400|g|oz}} 
|-
|U16|| {{cvt|600|g|lboz}}|| rowspan="2"| {{cvt|500|g|lboz}}
|-
|[[Under-18 athletics|U18]]|| {{cvt|700|g|lboz}} 
|-
|[[Under-20 athletics|Junior (U20)]] ||rowspan="3"| {{cvt|800|g|lboz}} || rowspan="3"|{{cvt|600|g|lboz}}
|-
|[[Open class (track and field)|Senior]]  
|-
|35–49 
|-
|50–74 || bgcolor=lightgrey colspan=1| || {{cvt|500|g|lboz}}
|-
|50–59 ||{{cvt|700|g|lboz}}|| bgcolor=lightgrey colspan=1|
|-
|60–69 || {{cvt|600|g|lboz}} || bgcolor=lightgrey colspan=1|
|-
|70–79 ||{{cvt|500|g|lboz}} || bgcolor=lightgrey colspan=1| 
|-
|75+ || bgcolor=lightgrey colspan=1| || {{cvt|400|g|lboz}}
|-
|80+ || {{cvt|400|g|lboz}} || bgcolor=lightgrey colspan=1| 
|}