Stackle competed for the University of Texas from 1986–1990, where he became a three-time individual NCAA Champion and 14-time all-American. His proudest accomplishments were leading Texas to NCAA Team Championship victories in 1988, 1989, and serving as team captain in1990. On the international stage, he represented the United States at the 1988 Olympic Games, the 1990 Goodwill Games, and the 1991 World Championships. Today, Stackle continues to give back to the sport as a coach in the Dallas area and as the owner of Stackle Swim Technique and Training, where he works with swimmers of all ages and backgrounds — including age-group, collegiate, professional, and masters swimmers and triathletes — helping people discover a lifelong love of the water and the physical and mental health benefits it brings.