An officer of the Afghan border police throws an assault rifle to a policeman participating in a military exercise on the outskirts of Herat, Afghanistan, Monday, September 7, 2015. Twelve female and seventy male border police personnel participated in the military exercise near the border with Iran in Herat province. (Photo by Hoshang Hashimi/AP Photo)

A U.S. army soldier exercises in front of a M270A1 multiple launch rocket system as they prepare for a live-fire training exercise of the 6-37th Field Artillery Regiment at a training area near the demilitarized zone separating the two Koreas, in Cheorwon, South Korea, March 9, 2016. (Photo by Kim Hong-Ji/Reuters)

A man exercises in the early morning on a hilltop overlooking Kabul, Afghanistan March 3, 2016. (Photo by Mohammad Ismail/Reuters)

A Tai Yai boy waits for a ceremony to begin at Wat Don Chedi on April 7, 2014 in Mae Hong Son, Thailand. Poy Sang Long is a Buddhist novice ordination ceremony of the Shan people or Tai Yai, an ethnic group of Shan State in Myanmar and northern Thailand. Young boys aged between 7 and 14 are ordained as novices to learn the Buddhist doctrines. It's believed that they will gain merit for their parents by ordaining. (Photo by Taylor Weidman/Getty Images)

Shan boys pray before they have their heads shaved in anticipation of their ordination in the Poy Song Long Ceremony at Wat Pa Pao in Chiang Mai, Thailand on April 3, 2018. Poy Sang Long (“The Festival of the Crystal Sons”) is a ceremony that marks a rite of passage among the Buddhist Shan people in Myanmar and northern Thailand. Boys between seven and fourteen years of age are ordained as Buddhist novices during a three day ceremony. Before the ceremony starts the boys have their heads shaved. (Photo by Jack Kurtz/ZUMA Wire/Rex Features/Shutterstock)

American soldiers leaping from an armoured personnel carrier during exercises in Korea, 17th March 1954. (Photo by Three Lions)

A 2S5 Giatsint self- propelled gun fires during tactical exercises held by artillery detachments of the Russian Eastern Military District' s 5th Army at the Sergeyevsky training ground in Primorye Territory, Russia on March 21, 2017. Over 2500 servicemen practice combat skills received in 2017 winter training exercises. (Photo by Yuri Smityuk/TASS)

A Thai Yoga enthusiast performs during a mass yoga exercise in Bangkok, Thailand, 16 June 2019. Hundreds of Thai and foreign Yoga enthusiasts took part in the mass Yoga exercise organized by the Indian embassy to mark the International Day of Yoga which annually celebrated on 21 June. (Photo by Rungroj Yongrit/EPA/EFE)