Here we can discuss the possible uses for brain monitoring devices such as determining how blood flows through the brain during emotional responses.
Posted on 28 April 2010.
Here we can discuss the possible uses for brain monitoring devices such as determining how blood flows through the brain during emotional responses.
Posted in Featured, Holistic Health0 Comments
Posted on 28 April 2010.
This post contains information about some everyday healthy foods that you can find and how to prepare them.
Posted in Diet and Foods, Featured0 Comments
Posted on 28 April 2010.
Several Tennis shots according to Wikipedia.
A competent tennis player has eight basic shots in his or her repertoire: the serve, forehand, backhand, volley, half-volley, overhead smash, drop shot, and lob.
Tim Henman preparing to hit a serve. The left arm is extended, having just launched the ball into the air. The right arm will be raised up and forward at speed so that the racket connects with the ball.
A serve (or, more formally, a “service”) in tennis is a shot to start a point. The serve is initiated by tossing the ball into the air and hitting it (usually near the apex of its trajectory) into the diagonally opposite service box without touching the net. The serve may be hit under- or overhand.
Experienced players strive to master the conventional overhand serve to maximize its power and placement. The server may employ different types of serve including flat serve, topspin serve, slice serve, and kick (American twist) serve. A reverse type of spin serve is hit in a manner that spins the ball opposite the natural spin of the server, the spin direction depending upon right- or left-handedness. If the ball is spinning counterclockwise, it will curve right from the hitter’s point of view and curve left if spinning clockwise.
Some servers are content to use the serve simply to initiate the point; however, advanced players often try to hit a winning shot with their serve. A winning serve that is not touched by the opponent is called an “ace”.
Players use various grips during play, including the continental (The “Handshake Grip”), eastern (Can be either semi-eastern or full eastern. Usually used for backhands.), and western (semi-western or full western, usually for forehand grips) grips. Different grips generally are used for different types of spin and shots.
Roger Federer preparing to hit a forehand. He is “loading” his body weight on his back (right) foot and coiling his shoulders with the help of his left hand. From this position, he will “uncoil” his body beginning with his legs, progressing to his hips and then on to his arms. This is how the “modern” forehand, utilizing the open stance, is executed.
For a right-handed player, the forehand is a stroke that begins on the right side of the body, continues across the body as contact is made with the ball, and ends on the left side of the body. There are various grips for executing the forehand, and their popularity has fluctuated over the years. The most important ones are the continental, the eastern, the semi-western, and the western. For a number of years, the small, apparently frail 1920s player Bill Johnston was considered by many to have had the best forehand of all time, a stroke that he hit shoulder-high using a western grip. Few top players used the western grip after the 1920s, but in the latter part of the 20th century, as shot-making techniques and equipment changed radically, the western forehand made a strong comeback and is now used by many modern players. No matter which grip is used, most forehands are generally executed with one hand holding the racquet, but there have been fine players with two-handed forehands. In the 1940s and 50s, the Ecuadorian/American player Pancho Segura used a two-handed forehand to achieve a devastating effect against larger, more powerful players. Currently, France’s Fabrice Santoro uses a two-handed forehand. Some females such as Monica Seles and France’s Marion Bartoli also use a two-handed forehand.
Rafael Nadal performing a backhand volley.
For right-handed players, the backhand is a stroke that begins on the left side of their body, continues across their body as contact is made with the ball, and ends on the right side of their body. It can be executed with either one hand or with both and is generally considered more difficult to master than the forehand. For most of the 20th century, the backhand was performed with one hand, using either an eastern or a continental grip. The first notable players to use two hands were the 1930s Australians Vivian McGrath and John Bromwich, but they were lonely exceptions. The two-handed grip gained popularity in the 1970s as Björn Borg, Chris Evert, Jimmy Connors, and later Mats Wilander and Andre Agassi used it to great effect, and it is now used by a large number of the world’s best players, including Rafael Nadal and Serena Williams. Two hands give the player more control, while one hand can generate a slice shot, applying backspin on the ball to produce a low trajectory bounce. Reach is also limited with the two-handed shot. The player long considered to have had the best backhand of all time, Don Budge, had a powerful one-handed stroke in the 1930s and 1940s that imparted topspin onto the ball. Ken Rosewall, another player noted for his one-handed backhand, used a very accurate slice backhand through the 1950s and 1960s. A small number of players, notably Monica Seles, use two hands on both the backhand and forehand sides.
Justine Henin performing a backhand volley.
A volley is made in the air before the ball bounces, generally near the net, and is usually made with a stiff-wristed punching motion to hit the ball into an open area of the opponent’s court. The half volley is made by hitting the ball on the rise just after it has bounced, once again generally in the vicinity of the net. The swinging volley is hit out of the air as the player approaches the net. It is an offensive shot used to take preparation time away from the opponent. From a poor defensive position on the baseline, the lob can be used as either an offensive or defensive weapon, hitting the ball high and deep into the opponent’s court to either enable the lobber to get into better defensive position or to win the point outright by hitting it over the opponent’s head. If the lob is not hit deeply enough into the other court, however, the opponent may then hit an overhead smash, a hard, serve-like shot, to try to end the point. Finally, if an opponent is deep in his court, a player may suddenly employ an unexpected drop shot, softly tapping the ball just over the net so that the opponent is unable to run in fast enough to retrieve it.
Posted in Featured, Fitness and Training, Tennis, Uncategorized0 Comments
Posted on 28 April 2010.
Here we will explain the basics of tennis, starting with match play according to Wikipedia.
A tennis match is intended to be continuous. Because stamina is a relevant factor, arbitrary delays are not permitted. In most cases, service is required to occur no more than 20 seconds after the end of the previous point. This is increased to 90 seconds when the players change ends (after every odd-numbered game), and a 120 second break is permitted between sets. Other than this, breaks are permitted only when forced by events beyond the players’ control, such as rain, damaged footwear, damaged racquet, or the need to retrieve an errant ball. Should a player be determined to be stalling repeatedly, the chair umpire may initially give a warning followed by subsequent penalties of “point”, “game”, and default of the match for the player who is consistently taking longer than the allowed time limit.
In the event of a rain delay, darkness or other external conditions halting play, the match is resumed at a later time, with the same score as at the time of the delay, and the players at the same end of the court when rain halted play, or at the same position (north or south) if play is resumed on a different court.
Balls wear out quickly in serious play and, therefore, in ATP and WTA tournaments, they are changed after every nine games with the first change occurring after only seven games, because the first set of balls is also used for the pre-match warm-up. As a courtesy to the receiver, the server will often signal to the receiver before the first serve of the game in which new balls are used as a reminder that they are using new balls. However, in ITF tournaments like Fed Cup, the balls are changed in a 9-11 style. Continuity of the balls’ condition is considered part of the game, so if a re-warm-up is required after an extended break in play (usually due to rain), then the re-warm-up is done using a separate set of balls, and use of the match balls is resumed only when play resumes.
A recent proposed rules change is to allow coaching on court during a match on a limited basis. This has been instituted in women’s tennis for WTA Tour events from 2009 onwards.
Posted in Featured, Fitness and Training, Tennis2 Comments