Kyle Casillas grew up in Costa Mesa, California. In 2003, Kyle enlisted into the United States Marine Corps and honorably served over eight and a half years as an infantry platoon sergeant. He was deployed three times to the Middle East and separated from the military in 2012. Kyle went to to attend the University of Hawaii at Manoa in 2015. While there, he served as a strength and conditioning coach with the Rainbow Warrior football program for 18 months. Post graduation, Kyle worked as a private performance coach for Ku Performance in Kailua, Hawaii. He worked with athletes of all levels from youth to professional.