Indonesian Presidential Security Forces (Paspampres) personnel show their skills during an anti terror exercise in Jakarta, Indonesia on 09 April 2015. The drill is in preparation for the 60th Asian-African Conference planned to be held in Jakarta from 21 to 23 April 2015. (Photo by Bagus Indahono/EPA)

Two railway workers chat in front of a flower mural inside a subway station visited by foreign reporters during a government organised tour in Pyongyang, North Korea October 9, 2015. (Photo by Damir Sagolj/Reuters)

An Indian sadhu (Hindu holy man) sits on the banks of Sangam – the confluence of the Ganges, Yamuna and mythical Saraswati rivers – on the auspicious bathing day of 'Maghi Purnima' during the Kumbh Mela festival in Allahabad on February 19, 2019. Millions of Hindu pilgrims took the plunge in holy rivers on the most auspicious bathing days of the Kumbh Mela festival, led by naked, ash-smeared holy men and accompanied by chants from Hindu holy texts. (Photo by Sanjay Kanojia/AFP Photo)

Children take part in the “Carnavalito” children's parade during the Blacks and Whites Carnival in Pasto, Colombia, on January 2, 2018. (Photo by Juan Barreto/AFP Photo)

Ukrainian territorial defence soldiers from the Donetsk Oblast fire D-20 artillery in the direction of Toretsk, Ukraine, 24 July 2025. (Photo by Diego Herrera Carcedo/Anadolu via Getty Images)

People line up to pay inside a Makro supermarket in Caracas, January 9, 2015. Venezuela's socialist government decreed an “economic emergency” on Friday that will expand its powers and published the first data in a year that shows the depth of a recession fueled by low oil prices and a sputtering state-led model. (Photo by Jorge Silva/Reuters)

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.

Participants celebrate during the “Chupinazo” (start rocket) to mark the kickoff at noon sharp of the San Fermin Festival, in front of the Town Hall of Pamplona, northern Spain, on July 6, 2018. (Photo by Jaime Reina/AFP Photo)