Yoga instructor Sarah Henry leads a class during a paddleboard yoga session at Adventure Sports Miami on July 10, 2011 in Miami, Florida. The paddle board is said to give the body's core more of a workout then in a gym since the platform is unstable and one must use the muscles to remain balanced on the board. (Photo by Joe Raedle/Getty Images)

Skeleton involves a person riding a small sled down a frozen track while lying face down. The sport is a more intense form of luge because skeleton competitors leap onto the sled and slide downhill head first. Skeleton athletes can reach up to 80 mph on straightaways, causing forces up to 5g, so the helmet is a critical component for attitude as well as safety.

Papai Simon Ole Mamai of the Maasai Cricket Warriors team from Kenya runs during a match against English team “The Shed” during “The Last Man Stands” cricket tournament at Dulwich sports ground in South London September 1, 2013. (Photo by Philip Brown/Reuters)

A competitor participates at the World Pole Dancing Championship 2012 held at the Volkshaus on November 10, 2012 in Zurich, Switzerland. The public's perception of pole dancing has recently changed to become a popular sport combining physical strength, technique and choreography. (Photo by Harold Cunningham)

Racegoers have their temperatures checked as they make their way into the course as a pilot scheme for the return of crowds to sporting events is expected to bring in 2500 spectators during day one of the William Hill St Leger Festival at Doncaster Racecourse, England on September 9, 2020. (Photo by BackGrid/The Sun)

May Matthews (left) and Romy Clark from Bonhams Edinburgh carry a carved wooden model of an Atlantic Salmon by Rogers Brookes (estimate £1,500-2,000) during a photo call for the upcoming Home and Interiors sale, and Sporting and Wildlife sale, at Bonhams, Edinburgh, on September 16, 2020. (Photo by Jane Barlow/PA Images via Getty Images)

A 10 km prologue dog sled race on the eve of the 2018 Beringia dog sled race in Russia' s Far East; the prologue race is part of the 2018 Russian Winter Dog Powered Sports Cup in Petropavlovsk-Kamchatsky, Russia on March 4, 2018. (Photo by Yuri Smityuk/TASS)

Wales' Gemma Frizelle competes in the Team Final and Individual Qualification Sub Division 2 at the Coomera Indoor Sports Centre during day seven of the 2018 Commonwealth Games in the Gold Coast, Australia on April 11, 2018. (Photo by David Gray/Reuters)