It's a little strange to consider, but a centuries-old fighting system might be the best core workout out there!
First, a little history lesson: Muay Thai is the national sport and a cultural martial art of Thailand. It originates several hundreds of years ago when used as a close-combat form that utilized the entire body as a weapon. Muay Thai employs stand-up striking, along with many other grappling techniques (called "clinching").
Muay Thai's discipline is referred to as the "Art of Eight Limbs" as it involves the use of elbows, fists, knees, and shins. Like many other forms of martial art, the practitioners, called nak muay, invest in themselves and their fighting success by strengthening their bodies to almost unthinkable heights.
The main goal in fighting Muay Thai is to beat down your opponent mostly through strikes. It’s ultimately good for both defensive and offensive fights. But, in the modern...