(CNN)Members of the Indo-Tibetan Border Police wear military fatigues, with thick boots and heavy jackets. On the job, they guard the vast border between India and China, where the mountaintop temperature can drop to minus 50 degrees Fahrenheit. Outside their regular duties, they summit Mount Everest.
This elite police force guards the Himalayas -- and also practices yoga
They also practice yoga.
In remarkable locations virtually inaccessible to the rest of the world, these "Sentinels of the Himalayas," often in full military gear, train in one of India's most renowned and ancient traditions as part of their well-being regimen. Their routines include physical and mental exercises, as well as breathing techniques that help members acclimate to the high altitude, which ranges from 9,000 to 18,000 feet.
Now, the elite police force -- along with yogis around the globe -- are marking Thursday's fourth annual International Yoga Day, which aims to raise awareness of the many benefits of practicing yoga.
India proposed the holiday in 2014 at the United Nations. With support from 175 other member states, the UN General Assembly passed a resolution proclaiming June 21 as the International Day of Yoga.
"Yoga embodies unity of mind and body; thought and action; restraint and fulfillment; harmony between man and nature; a holistic approach to health and well-being," Indian Prime Minister Narendra Modi told the UN General Assembly in 2014. "It is not about exercise but to discover the sense of oneness with yourself, the world and the nature."
The UN resolution highlighted the importance of "making healthier choices and following lifestyle patterns that foster good health."
It also underscored the goal of sharing best practices worldwide.
"Yoga is an invaluable gift of our ancient tradition," Modi said in 2014. (Three years later, India set a new precedent when more than 55,500 people participated in the largest-ever yoga class -- and set a Guinness World Record.)
Among those extolling yoga's benefits is the Indo-Tibetan Border Police, whose official website cites "adventure and dare-devilry" as required skills for new recruits.
The force's Twitter page, which features ample evidence of its members' epic mountaineering, rock-climbing and skiing skills, recently has been hyping #InternationalYogaDay2018. The feed's more than 86,000 followers have gotten glimpses of troops holding sessions atop frozen lakes and glaciers and on mountain plateaus overlooking the sweeping Himalayas.
They practice bridge pose, tree pose, crow pose and runner's lunge. They manage headstands and handstands. They sit cross-legged with outstretched palms, their thumbs and index fingers linked.
All the while, the warriors -- like yogis everywhere -- live out what the UN once lauded as a "holistic approach to health and well-being."