This summer China opened its door to its first private bodyguard training company in Beijing. Genghis Security Academy offers rigorous training course which includes aquatic training, martial arts, vehicle safety training and other necessary skills. Photo: Female and male trainees run during a bodyguard training program at the boot camp of Genghis Security Academy in Beijing, China. (Photo by ImagineChina/The Grosby Group)

A General Atomics MQ-9 Reaper stands on the runway during “Black Dart”, a live-fly, live fire demonstration of 55 unmanned aerial vehicles, or drones, at Naval Base Ventura County Sea Range, Point Mugu, near Oxnard, California July 31, 2015. (Photo by Patrick T. Fallon/Reuters)

A man from the Dani tribe cuts the head of a pig after cooked by traditional way which is use burned hot stones at Obia Village on August 9, 2014 in Wamena, Papua, Indonesia. The stone-age Dani tribe live a traditional existence in the Baliem Valley, which is situated 1600 metres above sea level in the heart of the Cyclops Mountains. (Photo by Agung Parameswara/Getty Images)

Members of the Legio X Fretensis (Malta) re-enactment group take part in a display of ancient Roman army life at Fort Rinella in Kalkara, outside Valletta, March 22, 2015. The event “Romanus”, organised by the Malta Heritage Trust, consisted of talks, hands-on displays, static exhibitions of weapons and equipment, food and wine tasting and large-scale re-enactments depicting different forms of Roman warfare in the field. (Photo by Darrin Zammit Lupi/Reuters)

Heather Larsen from Golden, Colorado, USA performs a split while walking the slackfline or highline across two towers in the Tower of David citadel complex overlooking the Old City of Jerusalem 02 May 2016. Larsen is one of the world's top female highliners, or slack liners and walked the lines as part of a Kickstarter campaign for an outdoor product. The tower at left was built by King King Herod some 2000 years ago. (Photo by Jim Hollander/EPA)

In this November 20, 2017 photo, Indian kushti wrestlers fight in the ring, during their daily training at an akhada, a kind of wrestling hostel at Sabzi Mandi, in New Delhi, India. Like many traditions in rapidly modernizing India, kushti wrestling faces the threat of being left behind. But for many poor families, the ancient sport provides a glimmer of hope. (Photo by Dar Yasin/AP Photo)

Sergeant Andrew Garrett watches K-Dog, a bottlenose dolphin attached to Commander Task Unit 55.4.3, leap out of the water while training near the USS Gunston Hall March 18, 2003 in the Persian Gulf. (Photo by U.S. Navy/Getty Images)

A villager pours brine into troughs at ancient salt fields on May 5, 2005 in Yantian Village on Hainan Island, China. (Photo by China Photos/Getty Images)