But 25 years and a seventh-degree black belt later, it's taken more than youthful hero worship to keep him in the sport.
Instead, it's the competition, the knowledge that he can take care of himself in a threatening situation, and the chance to share the physical and mental discipline with his students that has kept him active in the sport for so long.
Apparently, his students have the same drive to succeed; six recently returned from the 2008 International Karate Championships in Long Beach, Calif., hauling home a slew of trophies, with each team member placing in at least two divisions.
They made up one of the smallest teams to attend the meet, were the only group representing Idaho and ranged in age from 15 to 59, but each member managed to kick some kenpo butt.
Led by second-degree black belt Derrick Czarnecki, 27, the team—Tyler Deroin, 16; Jessica Knight, 15; Nancy Link, 59; Corey Rambough, 15; and Ali Rotta, 17—brought back 19 awards in a variety of categories. While it was welcome, the team's success caught even them a little off guard.
They smile humbly when asked to recall the moment they realized how well they were doing as a team, but their pride in accomplishment still shines though.
"It was awesome," said Rambough, a broad smile spreading across his face. "It was a 17-hour-long drive, and we were pumped the whole way."
The group competed against other kenpo students from around the world over the course of several days. They were divided into different classes depending on their belt level.
Kenpo events are split into different events, including forms, where athletes perform a set routine of movements as if they are fighting an invisible opponent. They also compete in sparring—in which points are awarded for hitting specific targets on an opponent's body—as well as the use of weapons and the display of self-defense skills.
All of the competition divisions revolve around the basic premise of kenpo as a self-defense technique, not as a sport. Hagood said the disciple combines aspects of several other martial arts to create a self-defense system in which practitioners use specific movements to respond to specific attacks.
Hagood stressed that the idea is never to instigate a fight but to be ready to defend yourself.
"It doesn't have to be aggressive," he said. "But once the person decides to defend themselves, it's nasty."
While the chance to compete was thrilling for the young students, it's all par for the course for the school, which has been training Treasure Valley karate students for more than 25 years.
Hagood started as a casual student himself, joining a class after a co-worker began teaching him kenpo karate in a park during their lunch break.
"My confidence level wasn't where it needed to be [in terms of] self defense," Hagood said. "I didn't want to be out of control."
A life-long athlete, Hagood felt immediately drawn to kenpo, a practice that appealed to him both in its physicality and the mental concentration required to advance. Kenpo, like many other forms of martial arts, stresses both self-discipline and respect.
"This is a life change," Hagood said, adding that students must show both physical and personal growth in order to earn advancements.
As Deroin and Rambough, both brown belts, demonstrated a carefully choreographed sequence of movements, Hagood explained that each student must have focused mental concentration as well as the physical knowledge to be able to do the exercise as it is intended.
He continued the tutorial as Rotta, a freshly minted brown belt, demonstrated self-defence techniques using Czarnecki as a target. Physical force is masked behind precise movements, but Hagood said students must have an understanding of their strength and the consequences of their actions in order to perform using full strength, but still pull the punches at the last second.
He smiled as he watched Rotta throw Czarnecki to the ground, pointing out that Rotta and Knight are girls who will never be caught off guard in a dark alley.
Hagood began teaching not long after he joined the school, originally located on Main Street in downtown Boise. It soon outgrew the space and in 1986, moved to its present home in downtown Meridian.
Based in a converted church, Hagood said the location caused some consternation just after the move. But decades later, the building is still a place of spiritual concentration—just of a different sort. Now the sanctuary is lined with gray mats, and what was once the altar now displays the school's sign and several of the ranking members' belts. Trophies and group pictures line the lobby, but visitors get the feeling that it's still a place of reverence.
In the 1980s, the karate scene in the valley was much larger, with up to four local tournaments each year. The opportunity for competition drove Hagood to succeed, and he was asked to be a member of the United States Kenpo Team three times, competing in Ireland, Sweden and Spain.
Most of the students who competed in California said they originally got into kenpo at the encouragement of, or even with, family, but found the camaraderie, support and competition kept them with it.
"It's kept me out of a lot of trouble," said Deroin.
The need to serve as a role model has also kept many of the more advanced students in line. As they climb the ranks, they begin working with some of the younger students.
"We're always on our game," Rambough said.
"You're more aware of the little things you do," Rotta said.
But those little things have forced the Idaho students to compete at a higher level than many of their peers from other schools.
While at the tournament in California, Czarnecki said the word was out on his team. "A couple of people said, 'Watch out for Team Idaho,'" he said with a smile as he remembered being the team to beat.
It's an experience that wasn't lost on the rest of the group, especially after they began racking up the wins.
"The [first] day of the tournament, they said they wanted to come back," Czarnecki said.