Figure - PMC

Skip to main content

An official website of the United States government

Here's how you know

Here's how you know

Official websites use .gov
A .gov website belongs to an official government organization in the United States.

Secure .gov websites use HTTPS
A lock ( ) or https:// means you've safely connected to the .gov website. Share sensitive information only on official, secure websites.

View full-text article in PMC

. 2010 Oct 6;5(10):e13161. doi: 10.1371/journal.pone.0013161

Search in PMC
Search in PubMed
View in NLM Catalog
Add to search

Dessing, Craig.

This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are properly credited.

PMC Copyright notice

(A) Top view of a subset of the used ball paths (orange = counter-clockwise spin [CCS]; blue = no spin [NS]; pink = clockwise spin [CS]). The dotted lines represent the ball's heading direction at 0.5 s. If the ball were to continue with this heading direction for these exemplary trajectories, the ball would pass the goal line at −3.1 m. The ball's instantaneous heading location (X_heading) is equal to (with ), which does not take lateral ball acceleration into account. (B) X_heading as a function of time before the ball passes the goal line. If goalkeeping movements are aimed towards the ball's heading location, and thus do not take lateral ball acceleration into account, movements would be biased in a leftward direction for CCS free-kicks (involving rightward acceleration) and in a rightward direction for CS free-kicks (involving leftward acceleration).

Inline graphic — (A) Top view of a subset of the used ball paths (orange = counter-clockwise spin [CCS]; blue = no spin [NS]; pink = clockwise spin [CS]). The dotted lines represent the ball's heading direction at 0.5 s. If the ball were to continue with this heading direction for these exemplary trajectories, the ball would pass the goal line at −3.1 m. The ball's instantaneous heading location (X_heading) is equal to (with ), which does not take lateral ball acceleration into account. (B) X_heading as a function of time before the ball passes the goal line. If goalkeeping movements are aimed towards the ball's heading location, and thus do not take lateral ball acceleration into account, movements would be biased in a leftward direction for CCS free-kicks (involving rightward acceleration) and in a rightward direction for CS free-kicks (involving leftward acceleration).