33

I've played with 1, 2 and 3 star balls. I'm not sure 4 or 5 star exist. Some companies have brands that they say are 4-star but they aren't actually rated above 3-star because a 3 star rating means the highest quality ball possible. The factors that go into the rating are durability, visibility of the seam on the ball, balance of the ball and elasticity. The ...


32

Actually, most swimmers at this level of competition wear two caps. Dana Vollmer, who won gold with a new world-record time in the 100m butterfly, actually lost her outer cap in the pool on the return leg of that event. Thus, the first reason; redundancy. These caps are latex rubber, which doesn't mix well with chlorine and will eventually degrade, and as ...


20

The oil is used to increase the grip or "tackiness" of the rubber surface of the racquet. You can actually just use ordinary oils (like sunflower oil) but the oils vendors sell are manufactured for the specific purpose of applying to table tennis rubber. Anyway, you want to use a medium width brush (like something you'd use to paint model airplanes or ...


20

The two caps are also made of different materials. The inner cap is latex, which stays on the head better, but wrinkles. The outer cap is silicone, better for reducing drag. "The outer silicone cap better maintains the shape and does not wrinkle as much, thereby causing less drag," Salo told Yahoo! Sports. - Why do Olympic-level swimmers wear two caps?...


20

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 ...


18

Yes, high tops appear to help with ankle injuries. A study was done by the National Center for Biotechnology Information to determine if there was a difference in ankle rotation when wearing high tops compared to wearing low tops. In the study the participants stood on a platform on one foot and the platform would be released at a random time which would ...


18

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....


17

From what I understand, there are 2 benefits to toe strap bindings: It helps you push the heel of your foot further back into the bindings There's less added pressure on the top of your toe, so more comfort. I have Burton Citizen bindings and my sister has a Burton Stilleto. I can tell you point 2 is definitely true. Our indoor snow area use T-Bars and ...


17

According to the official rules (referenced here): Rule 2.04.06 The surface of the covering material on a side of the blade, or of a side of the blade if it is left uncovered, shall be matt, bright red on one side and black on the other. The reasons for this rule are described here: The Two Colour Rule Since 1 July 1986 the rules of ...


17

It is for speed- if you have your goggles on over your cap it upsets water flow, so the second cap over that holds the goggles safely on and streamlines the head. Sure, it's an infinitesimally small benefit, but at that level it is important. Additionally, some sports manufacturers make some specifically to be worn like this to reduce drag further.


17

You are correct that this has to do with aerodynamics, more specifically drag and air friction. This article goes over all of the specifics. Ultimately, it boils down to less drag on the ball, allowing it to fly farther. The exact details and an explanation of the difference between a smooth sphere and a dimpled ball are included in the linked article. The ...


17

Rule 5, Section I-a of the NBA Official Rule Book states that, A legal field goal or free throw attempt shall be scored when a live ball from the playing area enters the basket from above and remains in or passes through the net. The ball just has to pass the hoop and not necessaily through the net. If the ball gets stuck in the net or breaks off the ...


16

The rules are very clear, the wicket keeper is the only player allowed to wear gloves. All other players would incur a 5 run penalty every time they touched the ball while wearing gloves. This includes for instance taking off your hat in order to use it to catch the ball (I have seen this done in a park cricket match!). See Law 41 in the rules of cricket ...


15

Since American football evolved partly from rugby1, it's no surprise that their shapes are similar. The main reason for the oblong shape is to allow carrying the ball by hand. A round ball kicks very well indeed, but is very easy to knock away; an oblong ball is still effective to kick and is much easier to grip. American footballs kept the same basic ...


15

Differences between red and white balls can vary based on the manufacturers. Kookaburra maintains that their red and white balls are manufactured using the same process apart from the dye used for colouring. They claim that the swing properties of both the balls are similar - as everything, apart from the colour, are the same. This, however, is disputed by ...


14

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 ...


13

There is a rule about this. From Wikipedia: American basketball leagues at all levels traditionally use single and double digits between 0 and 5 (i.e. 0, 00, 1–5, 10–15, 20–25, 30–35, 40–45, and 50–55). The NCAA and most amateur competitions mandate that only these numbers be used. This eases non-verbal communication between referees, who use fingers to ...


13

The major reason for using white ball in ODI and T20 is that many of those matches were happening as Day & Night matches and it was very difficult to spot the red ball under floodlights. Cricket balls were traditionally red and test matches still use that(Compared to red ball, white balls deteriorates more quickly and hence red balls are more suitable ...


13

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 ...


13

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 ...


13

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 ...


12

According to this site, 3 star ball are the ones that meet the ITTF's competition ball specifications for quality and consistency. 1 and 2 star balls are often the discarded balls from a 3 star production run.


12

There are a few things to look for on your skate blades to indicate it's time for sharpening. First would be visible nicks appearing anywhere along the length of the blade. You also want to look out for 'rounded' edges. Lastly you will want to avoid pitting which is quite common if you leave your cloth skate guards on your skates between sessions. Be ...


12

According to Law 6 of the Laws of Cricket, the length of the bat may be no more than 38 in (965 mm) and the width no more than 4.25 in (108 mm). If you wish to cover the blade with tape etc., the covering permitted for standard bats have to be of thickness not exceeding 0.012 in (0.3 mm) before treatment. When it comes to the handle, it should not exceed 52%...


12

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 ...


12

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 ...


11

All other things being equal: A larger frame generates more power. A larger frame is more resistant to twisting. A larger frame has a larger sweet spot. Smaller frames are known for control oriented play, ie serve and volley. With advancements in racket technology, many players are able to use larger frames without having to sacrifice control. You should ...


11

There is a law regarding such situation: See IFAB Law 4 - The players' equipment: A player whose footwear or shinguard is lost accidentally must replace it as soon as possible and no later than when the ball next goes out of play; if before doing so the player plays the ball and/or scores a goal, the goal is awarded.


10

For short course triathlon as you suggest it is not worth worrying this much about shoes. Either use pedals with clips and straps (cages if you will) and ride in your running shoes, or else switch shoes in transition. For your runners, they sell stretchy laces so you can slip the shoes on, no need to retie the laces. This will minimize transition time. ...


10

NB: hims056's answer is correct according to the law but I will add the following supporting information. A lot is said in football about the referee's "interpretation" of the rules in a match. In the interpretation of this law, we should look closely at the term "immediately". You will very rarely see a referee award a free kick against a player who ...


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