It's called "Vanishing foam".
It is used by the referees to indicate the minimum distance the players must maintain from ball, in the event of a free kick, as well as the spot from where it is taken.
Some technical details:
The can contains water (~80%), butane gas (~17%), surfactant (~1%), and other ingredients including vegetable oil (~2%).
The foam is ...
They are performance trackers. They track a player's vital statistics (heart rate, etc) as well as their movement. Their average speed, their distance covered, etc. As for the "bra-like" design, it would appear to just be the result of needing a small and unencumbered design that allows for minimal interruption, maximum body contact, and full range of motion....
It's just a matter of convenience.
If a batsman has to tie his own shoelaces, he has to remove his gloves, and also look around his pads. Try wearing pads, kneeling down, and tying your shoelaces. You'll see the pads do seem to get in the way. Also, it's not like the batsman walks very far to ask a fielder/umpire to do this. He only asks the nearest person ...
GB11's answer summarized it well what are the tracking devices. From the YouTube page of GPSSports Systems you can see that what Zlatan wears is called GPSports SPI HPU tracking device, which according to its brochure has many features, some of them being GPS, accelerometer, wireless communication, water resistance, 5.5 hours battery life, etc.
The data ...
The precise rules for clothing are published by the international sport federations (FIVB for Beach Volleyball, FIG for gymnastics, FINA for Swimming etc.). Typically, they consist of
basic rules which concern safety and fairness instead of appearance.
clothing regulations to all (top-level) competitions (e.g. limits on advertising)
separate rules typically ...
In general, the "anti-vandal" or "anti-theft" refers to the goal frames themselves, rather than the nets; there's very little you can do if someone is actually out to vandalise the net with a big pair of scissors or equivalent. The simplest solution by far is just to put the nets up when you need them - this then just becomes a question of whether it is more ...
Soccer balls are a bit different from the balls in other sports. They are often very colorful and are a significant part of the brands of the companies that make them.
Unlike in sports like Baseball and American Football where a couple of suppliers make all of the baseballs for pretty much all levels of the game, and they are all identicle except the ...
The FIFA equipment regulations mandate:
7.6 The letters used for the Player’s name must be (...) Latin characters. Phonological diaeresis, such as accents or umlauts, are permitted.
So the answer to both of your questions is: Because the FIFA laws say so.
I can only speculate as to why these laws are there. Most likely, referees and spectators will ...
New balls are requested by the chair umpire after the first 7 games of the match, and then every 9 games thereafter. It is done this way since the players warming up with the first set of new balls is considered to amount to the normal wear and tear of 2 games.
When the chair umpire calls for new balls, the ball kids (if present) will collect the balls and ...
Cricket has its origins as a gentleman's summer sport as opposed to football which has traditionally been a working man's sport. Cricket has hence had high clothing and cricketers have been very well-dressed since its nascent beginnings.
Moreover, cricket during its early stages was not a very athletic game like what football is. Hence there was no acute ...
I can suggest you one of those three solutions:
use it without net except during official games, on these occasions you should assemble and dismantle the net with a consequent loss of time
add wheels to completely remove the goal frames at the end of matches/trainings
use rigid net (it is easy to see it on 3 vs 3 ground, but I do not know if exists for ...
According to this article:
The kit man takes three shirts per player to each game – one per half,
plus a spare for emergencies. Afterwards, he collects and launders
them, ready for next week. For big games, the club permits the players
to swap or keep their shirts, but that is agreed beforehand and the
players are fined if they do it when they’re ...
As with much of this stuff, this is explicitly covered in the Laws of the Game. In this case, Law 1 The Field of Play, Goalposts (page 9):
The goalposts and crossbar [...] must be square, rectangular, round or elliptical in shape and must not be dangerous to players.
Given that the Laws explicitly allow square or rectangular posts, I don't think you're ...
Good question. A common mistake is to select a bat that is too big for a young player. The temptation may be to buy a large bat for the player to "grow into", to save money as much as anything else, but it's definitely not a good idea. The bat should feel comfortable to and manoeuvrable by the player.
Bob Woolmer's Art and Science of Cricket has this to say ...
The FIFA regulations on the ball are found in FIFA 2014/2015 Laws of the Game (PDF), Law 2:
LAW 2 - THE BALL
Qualities and measurements
The ball is:
made of leather or other suitable material
of a circumference of not more than 70 cm (28 ins) and not less than
68 cm (27 ins)
not more than 450 g (16 oz) and not less ...
According to FIFA's Laws of the game PDF
The size of the goalpost is 7.32 m (8 yds) x 2.44 m (8 ft).
The distance between the posts is 7.32 m (8 yds) and the distance from the
lower edge of the crossbar to the ground is 2.44 m (8 ft).
Other characteristics (taken from the same law):
A goal consists of two upright posts ...
Major league players, managers and coaches are required to abide by strict uniform guidelines. They are required to be in uniform, but can also wear other team apparel on top to stay warm.
However, some managers have elected not to comply and wear just a team pullover for various reasons. MLB can and does check and fine repeat offenders.
Terry Francona's ...
There doesn't seem to be an explicit line in the rules for when to use them. The only mention in the rulebook is in Rule 2:
SECTION 2 - SUPPLY
Each team will make 12 primary balls available for testing by the Referee two hours and 15 minutes prior to the starting time of the game to meet League requirements. The home team will also make 12 backup balls ...
The check at the start of the game is a simple safety check.
There are no specific rules governing types of footwear except that they "should not be dangerous".
In practice this means that the ref is looking for:
Worn plastic studs that have developed a sharp plastic lip at the top (usually from walking on concrete) that could cut someone.
Sharp studs - ...
There are two rules of thumb to determine your correct tennis racket grip size:
Hold the racket by the handle as you would while playing and see if you can insert your your non-dominant index finger in the space between your palm and ring finger tip. If your index finger is snug, the grip is sized correctly.
A player can measure his or her grip size with a ...
As stated on the Mongoose website:
We believe that when a ball gets hit, it should stay hit. That’s why
we design our bats with two principal advantages over anything else in
cricket: faster bat speed and bigger sweet spots.
The bat’s extra power comes from increased rigidity in the blade and
increased flexibility in the handle – so you ...
It contains anesthetics. When players get hit or tackled they could be in great amount of pain, but their team still needs them to play. The physicians apply the spray and the injured body part goes numb, so players can continue playing with no pain.
Tennis balls are mostly airtight. They're made of rubber covered with felt; the rubber is quite good at keeping air in, but not perfect. Some of the answer as to why they are not more airtight is due to cost (it would cost more), some is tradition (tennis balls are largely built the same way they always have been, at least in a long time), and some is ...
Generally, footwear is a part of the basic compulsory equipment, i.e. no player can play barefoot:
The basic compulsory equipment of a player comprises the following separate items:
(FIFA Laws of the Game 2015/2016, Law 4 – The Players’ Equipment)
However, that does not mean the player would have to stop playing immediately ...
The FIFA Equipment Regulations state (Article 65):
In the event that, in the opinion of the referee or Match Commissioner,
the Playing Equipment of the two opposing teams is not clearly distinguishable
for all Players, the Match Officials, spectators and media under the prevailing
conditions, such as weather and light, the referee or Match ...
Which manufacturers cricket balls are currently used at Test level, and by which teams?
India - SG
England - Dukes
New Zealand, South Africa, Bangladesh, Zimbabwe, Sri Lanka, Pakistan, Australia - Kookaburra
What is the difference?
Kookaburra has a very low seam which generally holds true for 20 overs and then dies after that.
The seam in the SG ...
As per FIFA's "Equipment Regulations", Section 22, only the goalkeeper is permitted to wear a cap.
22.1 All goalkeepers may, irrespective of the prevailing conditions, wear a
goalkeeper cap of any Colour. The goalkeeper cap must be produced by the
Manufacturer of a Playing Equipment item. The goalkeepers of the same team
may wear different ...