{{short description|Rubber half-sphere used for fitness training}} thumb|250px|Two people in a gym using BOSU balls. thumb|Half ab ball or BOSU Ball A '''BOSU Balance Trainer''' (or '''BOSU ball''') is a fitness training device, invented in 1999 by David Weck.<ref name="bosu-history">{{cite web | url=https://balance.lifetips.com/faq/120190/0/what-is-a-bosu-ball-and-how-does-it-improve-balance/index.html | title=What is a BOSU ball and how does it improve balance? | publisher=Lifetips.com | accessdate=February 13, 2013 | author=Chan, Christina}}</ref> It consists of an inflated rubber hemisphere attached to a rigid platform. The device is often used for balance training. When the dome side faces up, the BOSU ball provides an unstable surface while the device remains stable. This combination of stable/unstable allows a wide range of users, from the young,<ref name="bosu revitalized">{{cite web|url=http://www.hedstromfitness.com/bosurevitalized.htm |title=BOSU Revitalized |publisher=Hedstromfitness.com |accessdate=April 13, 2015 |author=Hedstrom Fitness }}{{dead link|date=October 2016 |bot=InternetArchiveBot |fix-attempted=yes }}</ref> elderly, or injured to the elite level athlete.<ref>{{cite web|url=http://www.canada.com/vancouversun/news/arts/story.html?id=2ab47496-0443-4d09-8371-202ddddf6276&k=17840 |title=More training tips from NBA superstar |publisher=Canada.com |date=2007-03-26 |accessdate=2015-04-03 |url-status=dead |archiveurl=https://web.archive.org/web/20150613085632/http://www.canada.com/vancouversun/news/arts/story.html?id=2ab47496-0443-4d09-8371-202ddddf6276&k=17840 |archivedate=2015-06-13 }}</ref> With the dome side up, the device can be used for athletic drills and aerobic activities. The device can be flipped over so that the platform faces up. In this position, the device is highly unstable and can be used for other forms of exercise.
The name initially came from an acronym standing for “Both Sides Utilized" - a reference to the two ways a BOSU ball can be positioned. It is also referred to as the "blue half-ball", because it looks like a stability ball cut in half. The acronym now favored by the creators is "BOth Sides Utilised".<ref name="About Us Bosu">{{cite web | url=https://www.bosu.com/about-us | title=About Us - BOSU | publisher=BOSU | accessdate=October 28, 2020}}</ref>
==References== {{Reflist}}
==External links== *[http://www.bosu.com BOSU homepage] *[https://www.weckmethod.com BOSU inventor's homepage]
Category:Exercise equipment Category:Exercise-related trademarks