Sports medicine & Kinesiology

Running research: Heel-toe or toe-heel?

New research from La Trobe University suggests there is no evidence that changing a runner's strike pattern will help prevent injuries or give them a speed boost.

Neuroscience

How the brain regulates variability in motor functions

Anyone who has ever tried to serve a tennis ball or flip a pancake or even play a video game knows, it is hard to perform the same motion over and over again. But don't beat yourself up—errors resulting from variability ...

Sports medicine & Kinesiology

Quad training for knee support

Whether you're mountain biking, kicking a soccer ball with friends, or just sprinting down the street to catch a bus, your quadriceps are hard at work.

Health

Why do I grunt when I bend over?

You never think it's going to happen to you. Then suddenly you're middle-aged and you find yourself grunting when you pick up something from the floor or groaning when you get out of the chair.

Health

Exercises to head off a painful rotator cuff injury

(HealthDay)—The rotator cuff refers to a group of four distinct muscles and tendons that connect to each shoulder and stabilize the humerus, the upper arm bone. These muscles are engaged when you move your shoulder, and ...

Psychology & Psychiatry

How grunting influences perception in tennis

Exceeding noise levels of 100 decibels, the grunting sounds produced by some tennis players when hitting the ball are on a par with motorbikes or chainsaws. While fans react to these impressive exhalations with either annoyance ...

Psychology & Psychiatry

Who really hit the basketball out of bounds?

The shot clock reads 5, and a win forces a game 7. Two hands outstretched as the players—one in royal blue and yellow, the other black—hurtle towards the edge of the court. The ball sails out of bounds, and the play ends. ...

Health

A new twist to work your obliques

(HealthDay)—Obliques are the muscles that run along the sides of your torso, from the lower eight ribs to the front of the hip bone. They contract when you rotate your torso, so a great way to develop them is with an exercise ...

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Ball

A ball is a round, usually spherical but sometimes ovoid, object with various uses. It is used in ball games, where the play of the game follows the state of the ball as it is hit, kicked or thrown by players. Balls can also be used for simpler activities, such as catch, marbles and juggling. Balls made from hard-wearing materials are used in engineering applications to provide very low friction bearings, known as ball bearings. Black powder weapons use stone and metal balls as projectiles.

Although many types of balls are today made from rubber, this form was unknown outside the Americas until after the voyages of Columbus. The Spanish were the first Europeans to see bouncing rubber balls (albeit solid and not inflated) which were employed most notably in the Mesoamerican ballgame. Balls used in various sports in other parts of the world prior to Columbus were made from other materials such as animal bladders or skins, stuffed with various materials.

As balls are one of the most familiar spherical objects to humans, the word "ball" is used to refer to, or to describe, anything spherical or near-spherical.

This text uses material from Wikipedia, licensed under CC BY-SA